drewno - Instytut Technologii Drewna

Transcription

INSTYTUT TECHNOLOGII DREWNA
WOOD TECHNOLOGY INSTITUTE
DREWNO
PRACE NAUKOWE ● DONIESIENIA
KOMUNIKATY
WOOD
RESEARCH PAPERS ● REPORTS ● ANNOUNCEMENTS
Vol. 54
POZNAŃ 2011
Nr 186
Wydanie publikacji dofinansowane przez Ministerstwo Nauki i Szkolnictwa Wyższego
The journal is financially supported by Polish Ministry of Science and Higher Educations
Recenzenci (Reviewers): prof. dr Levente Dénes, prof. dr hab. Danuta Krutul, mgr inż.
Andrzej Noskowiak, dr inż. Grzegorz Pajchrowski, prof. dr hab. Stanisław Proszyk, dr
hab. Grzegorz Wieloch, dr hab. Adam Wójciak
Publikacje indeksowane są w bazach danych (Publications are indexed in the databases): Science Citation Index Expanded – http://thomsonreuters.com, BazTech – http://
baztech.icm.edu.pl, DREWINF – http://www.itd.poznan.pl, The Central European Journal
of Social Sciences and Humanities – http://cejsh.icm.edu.pl
W 2010 roku czasopismo znalazło się na tzw. Liście Filadelfijskiej (ISI Master Journal
List) z obliczonym Impact Factor (IF).
W 2010 roku czasopismo zostało uhonorowane Medalem im. Michała Oczapowskiego.
Artykuły polskojęzyczne zawierają streszczenia w języku angielskim, a obcojęzyczne –
w języku polskim. Spisy treści, streszczenia i pełne teksty artykułów są dostępne na stronie www.itd.poznan.pl/pl/drewno
In 2010 the journal was indexed on ISI Master Journal List with calculated Impact Factor (IF).
In 2010 the journal was honored with Michał Oczapowski Medal.
Polish language articles have summaries in English language, and foreign language articles have summaries in Polish language. Tables of contents, summaries, and full versions
of the articles are available at www.itd.poznan.pl/pl/drewno
Wydawca (Publisher): Instytut Technologii Drewna
ul. Winiarska 1, 60-654 Poznań, Polska (Poland)
Adres Redakcji (Editor’s address): Instytut Technologii Drewna
ul. Winiarska 1, 60-654 Poznań
tel. +48/61 849 24 01, +48/61 849 24 61, fax +48/61 822 43 72,
e-mail: [email protected]
© Copyright by Instytut Technologii Drewna w Poznaniu
Poznań 2011
ISSN 1644-3985
Projekt okładki (Cover design): Piotr Gołębniak
Redaktor (Editor): Edward Grześkowiak
Skład komputerowy (Computer typesetting) oraz druk (print):
Studio Poligrafia, ul. Bułgarska 10, 60-321 Poznań, tel. 61 867 53 72
Nakład (Edition): 520 egz.
SPIS TREŚCI – CONTENTS
Prace naukowe – Research papers
Mariusz Jóźwiak, Juliusz Pernak, Mariusz Kot: Protic ionic liquids as a new
hardener-modifier system for melamine-urea-formaldehyde adhesive resins (Protonowe ciecze jonowe jako nowe utwardzacze - modyfikatory klejowych żywic melaminowo-mocznikowo-fomaldehydowych) ......................
5
Xue-Fei Zhou, Jian-Xin Qin, Shu-Rong Wang: Oxidation of a lignin model compound of benzyl-ether type linkage in water with H2O2
under an oxygen atmosphere catalyzed by Co(Salen) (Utlenianie modelowego związku ligniny z typem wiązania benzylowo-eterowego w wodzie z H2O2
w atmosferze tlenu katalizowane Co(Salen)) ................................................
15
Ladislav Dzurenda, Kazimierz A. Orlowski: The effect of thermal modification
of ash wood on granularity and homogeneity
��
of
��
sawdust in the sawing process on a sash gang saw PRW 15-M in view of its technological usefulness
(Wpływ modyfikacji termicznej drewna jesionowego na ziarnistość i jednorodność trocin z procesu przecinania na pilarce ramowej wielopiłowej
PRW 15-M w aspekcie ich przydatności technologicznej) .............................
27
Iwona Frąckowiak, Franciszek Warcok, Dorota Fuczek, Cezary Andrzejak:
The influence of UF molar ratio on selected particleboard properties
(Wpływ stosunku molowego żywicy UF na wybrane właściwości płyt wiórowych) ...........................................................................................................
39
Agata Stachowiak-Wencek, Włodzimierz Prądzyński: Emission of volatile
organic compounds (VOC) from waterborne lacquers with different content of solids (Emisja lotnych związków organicznych (VOC)
z wodorozcieńczalnych wyrobów lakierowych o zróżnicowanej zawartości
ciał stałych) ..................................................................................................
51
Doniesienia naukowe – Research reports
Mária Krajčovičová: Determination of bottlenecks in the production of wooden constructions (Określenie wąskich gardeł w produkcji konstrukcji
drewnianych) ................................................................................................
65
Komunikaty – Announcements
Weronika Przybylska, Jadwiga Zabielska-Matejuk: Światowy kongres na temat cieczy jonowych Coil-4 (The 4th congress on ionic liquids) ...............
75
Kazimierz A. Orłowski: 20. Międzynarodowe seminarium mechanicznej obróbki drewna w Szwecji (20th International wood machining seminar) .......
79
Andrzej Fojutowski, Władysław Strykowski: FTP-C7 – session of the European Forest-Based Sector Technology Platform (FTP) in Warsaw (FTP-C7 –
Obrady Europejskiej Platformy Technologicznej Sektora Leśno-Drzewnego
w Warszawie) .................................................................................................
85
Ewa Ratajczak: Early stage researchers from throughout Europe presented
their research in forestry-wood sciences (Młodzi naukowcy z całej Europy
o wynikach własnych badań z zakresu leśnictwa i drzewnictwa) ................
89
Drewno. Pr. Nauk. Donies. Komunik. 2011, vol. 54, nr 186
PRACE NAUKOWE - RESEARCH PAPERS
Mariusz Jóźwiak, Juliusz Pernak, Mariusz Kot1
PROTIC IONIC LIQUIDS AS A NEW HARDENER-MODIFIER
SYSTEM FOR MELAMINE-UREA-FORMALDEHYDE
ADHESIVE RESINS
This paper presents the results of investigations on the possibility of using protic
ionic liquids as a hardener and modifier of melamine-urea-formaldehyde (MUF)
adhesive resins. In research dialkylmethylammonium dodecylbenzenesulfonate
base protic ionic liquids with varied amounts of carbon in alkyl group were used.
The plywood manufactured using protic ionic liquids and MUF resin was characterized by a complete water resistance of glue lines, thus meeting the requirements
of EN-314-02 standard.
Keywords: MUF adhesive resin, protic ionic liquid, modifier-hardener system,
plywood
Introduction
For the curing of adhesive amino resins we use ammonium salts of strong inorganic acids, primarily nitrates, sulfates and chlorides (coming out of use for environmental reasons), inorganic acids (phosphoric acid) and organics (formic acid,
oxalic acid), as well as acid anhydrides [Pizzi 1994]. In order to increase hydrolytic resistance of adhesive joints, melamine salts are used [Weinstabl et al. 2001;
Zanetti, Pizzi 2003, 2004].
Much research on alternative hardeners that cause viscoelastic dissipation
of energy of glue lines and an increase in their resistance to external factors has
Mariusz Jóźwiak, Wood Technology Institute, Poznan, Poland
Juliusz PERNAK, Poznan University of Technology, Poland
Mariusz KOT, Poznan University of Technology ,Wood Technology Institute, Poznan, Poland
6
Mariusz Jóźwiak, Juliusz Pernak, Mariusz Kot
been conducted independently [Wang, Pizzi 1997; Proszyk et al. 2002; Pizzi
et al. 2002; Zanetti et al. 2002; Kamoun, Pizzi, Zanetti 2003; Zanetti, Pizzi 2004].
In the Wood Technology Institute we have been studying a new generation
of “multitasking” hardener of amino resins. Based on preliminary studies,
we have found that ionic liquids can meet these expectations.
Ionic liquids are chemical organic compounds composed solely of ions
(cation and anion) and having a melting temperature below the boiling point
of water [Deetlefs, Seddon 2010; Kichner 2009]. Ionic liquids have been applied
in many fields of human activity [Rogers, Seddon 2002; Wasserscheid, Welton
2008]. They have also been broadly used in wood technology, especially in wood
preservation [Han et al. 2008; Pernak et al. 2008; Stasiewicz et al. 2008; Pernak
et al. 2004, 2005, 2006, 2008; Zabielska-Matejuk et al. 2004; Zabielska-Matejuk
2005]. Ionic liquids are often referred to as “designed compounds”, and they owe
this description to the fact that they offer a possibility of modelling their properties
by selecting cation and anion. This creates the possibility of obtaining compounds
that, in addition to cross-linking properties, allow the adhesive bond to obtain the
desired physical and mechanical properties.
From this perspective, it can be interesting to apply protic ionic liquids
(PILs). They are a special case of ionic liquids that are synthesised by the transfer
of a proton derived from the acid to the free electron pair on the nitrogen atom
present in the amine [Welton 1999].
This paper presents the results of conducted research on the usefulness
of dialkylmethylammonium dodecylbenzenesulfonate base protic ionic liquids as
a hardener-modifier system for melamine-urea-formaldehyde adhesive resin.
Materials and methods
General procedure for synthesis of protic ionic liquids
All reagents were purchased from a commercial source (Sigma-Aldrich) and used
as received. 0.05 mol of tertiary amine was dissolved in 100 cm3 of methanol and
then 0.05 mol of dodecylbenzenesulfonic acid (70%) was added. The solution was
stirred at cool bath in 20oC for 30 min. Methanol was then removed in vacuum.
Next, in order to obtain hydrophobic ionic liquids, water (50 cm3) was added to
the raw product and then the mixture was shaken. The mixture was stirred for an
additional 30 min. After the separation of phases, the organic phase was washed
with 10 cm3 of distilled, cold water until free amine was no longer detected. Water
was then removed and the residue was dried at 50oC in vacuum.
In this research PILs with alkyl substituent of the following amounts of carbon
were used: 4 (butyl – C4H9 ) , 6 (hexyl – C6H13), 8 (oktyl – C8H17), 10 (decyl – C10H21).
PILs were developed and synthesised in the Institute of Chemical Technology and
Engineering, Poznan University of Technology.
Protic ionic liquids as a new hardener-modifier system for melamine-urea-formaldehyde adhesive resins
7
R = CnH2n+1 where n = 4, 6, 8, 10
Fig 1. Reaction of synthesis of protic ionic liquids
Rys.1. Reakcja syntezy protonowych cieczy jonowych
MUF resin
In our studies we applied MUF resins condensed on a lab scale for the molar ratio
of formaldehyde : melamine : urea as follows 3.8 : 1.0 : 1.0. The condensation
was a three-stage process performed at a temperature of 82 ± 2°C and 0.2 mole
of urea was additionally condensed in the third stage. Condensation was carried
out to water tolerance in the range of 100 ÷ 130%. Polycondensate was not
distilled. The synthesis details are presented hereinbefore [Jóźwiak, Proszyk,
Jabłoński 2003]. The resins were stored at a temperature of 20 ± 2°C.
The basic physicochemical properties of the resin were determined using the
following methodologies:
–– apparent viscosity using Emil rotational viscometer in accordance with
PN-92/C-89402,
–– content of dry mass according to DIN EN 827 (weighed sample 2.0 ± 0.1 g
was dried in a thermal chamber with natural air circulation, at 120 ± 1°C for
120 ± 1 min),
–– pH applying pH-meter with combined electrode, according to PN-ISO 1148,
–– gel time at 100°C, according to BN 75/3537-01,
–– free formaldehyde content by sulphite method, according to DIN EN 1243.
The MUF resin was characterised by the following basic properties: apparent
viscosity of 35 mPa.s, solid content 52.3%, pH value 9.48, gel time at 100°C –
103 s, and free formaldehyde content 0.76 %.
Preparation of glue mixtures
To arrive at the technological conditions that are necessary for the appropriate
bonding of adhesives, the viscosity of polycondensate was increased by adding
potato starch to the amount of 5% of solid mass of the resin, thus obtaining a viscosity of 2100 ± 100 mPa.s. The gelatinization process was carried out in a water
bath at 80 ± 2°C.
Then protic ionic liquids in the amount of 20% of solid mass of the resin
were added. For control purposes, the glue mixtures hardened with solid NH4NO3
to the amount of 3.2% of solid mass of the resin were prepared.
8
The gel time at 100°C for the glue mixture (without starch) was determined
independently according to the BN 75/3537-01 standard.
Preparation and test of plywood
The glue mixtures were spread in a quantity of 180 g/m2 on the surfaces of beech
veneer. Three-layered plywood in the form of 300 × 300 mm sheets that were
1.8 mm thick (moisture content of veneer 6 ± 1% was glued after 40 min assembly
time with the use of a laboratory press in the following conditions: unit pressure
1.8 MPa, temperature 125 ± 2°C and time 10 min. The plywood was prepared for
selected variants (PIL-butyl and PIL-decyl) after 1 day and 30 days after application
of the glue mixtures. The plywood was produced using the same pressing parameters. All plywood types were conditioned for 7 days in standard atmosphere,
i.e. temperature of 23 ± 2°C and relative humidity of 50 ± 5%.
Then samples were cut to determine the shear strength (Rt) of the adhesive
glue line of the plywood in accordance with the EN 314-1 standard. Before determining the shear strength of the bonds, the samples were subjected to hydrothermal treatments in accordance with item 5.1.1 (24 h soaking in water at a temperature of 20 ± 3°C) and 5.1.3 (4 h boiling in water as well as 16 h drying in
air at a temperature of 60 ± 3°C and 4 h boiling in water and cooling in water to
a temperature of 20 ± 3°C) of the EN314-1 standard. All the samples were tested
wet in a Schopper testing machine at loads up to 500 daN. Rupture of the samples
occurred within 30 ± 10 s. After shear tests, the samples were dried and the percentage share of the bond surface covered with wood fibers, i.e. wood failure
(WF), was determined by comparing the pictures of bond damage with those presented in the EN 314-1 standard.
Results
The results of research on the application of protic ionic liquids in plywood manufacturing technology are summarised in tables 1 and 2 and illustrated
in fig. 2 and 3.
The gel time at 100°C of the adhesive glue mixtures ranged from 287 s
(PIL-butyl group) to 540 s (PIL-decyl). During the test a strong foaming of
the adhesive mixtures was observed. A cured adhesive was characterised by
relatively high flexibility (low hardness) compared to the control variant.
Organoleptic assessment indicated that the adhesive could be modified under the
influence of PIL. The gel time of PIL-cured adhesive masses was from 3 to 6 fold
higher compared with the control hardener NH4NO3 (gel time 96 s) used. For these reasons, the plywood pressing time was set at 10 min.
Protic ionic liquids as a new hardener-modifier system for melamine-urea-formaldehyde adhesive resins
9
Table 1. Shear strength and wood failure of three-layer beech plywood with MUF
resin hardened with PILs with different amounts of carbon in alkyl group after tests
according to EN 314-01 standard
Tabela 1. Wytrzymałość na ścinanie i udział ścięcia próbki w drewnie trzywarstwowych sklejek bukowych po testach według EN 314-01 uzyskanych z żywicy MUF utwardzanej protonowymi cieczami jonowymi z różną liczbą atomów węgla w grupie alkilowej
Hardener type
Shear strength and wood failure
of plywood after tests according
to EN 314-01
Wytrzymałość na ścinanie i udział
ścięcia próbki w drewnie po testach
wg EN 314-01
Type of
test
Rodzaj
testu
item
5.1.1.
IF-20
item
5.1.3.
AW-100
Basic
statistics
Unit
Statystyki
Miano
podstawowe
Typ utwardzacza
Alkyl group in PILs
Grupa alkilowa w protonowej cieczy jonowej
Control
Kontrolny
C4H9
C6H13
C8H17
C10H21
NH4NO3
3.48
3.08
2.53
0.40
3.89
3.14
2.40
0.55
3.91
3.33
2.76
0.41
3.58
3.04
2.52
0.40
xmax.
xavg.
xmin.
δn-1
MPa
3.62
2.97
2.23
0.46
ν
WF
%
15.3
85
13.0
95
17.4
99
12.4
95
13.1
95
xmax.
xavg.
xmin.
δn-1
MPa
2.73
2.39
1.74
0.34
3.22
2.73
1.73
0.43
3.48
2.65
1.81
0.65
2.88
2.48
2.01
0.29
3.01
2.62
1.88
0.39
ν
WF
%
14.1
20
15.8
60
24.4
60
11.5
20
15.0
50
xmax. – maximum, xavg. – average, xmin. – minimum, δn-1 – standard deviation, ν��
��
– variation coefficient, WF – wood failure
xmax. – maksimum, xavg.– średnia, xmin.– minimum, δn-1 – odchylenie standardowe, ν – współczynnik zmienności, WF – zniszczenie w drewnie
The effect of the size of the alkyl group in cation in PIL on the reactivity
mass of the MUF adhesive resin is presented in fig. 2. It can be observed that
with an increase in the number of carbon atoms in alkyl group, the reactivity
of the adhesive mass decreased to increase the gel time. The relationship was
linear with a high correlation coefficient (r2 = 0.972). This phenomenon can be
explained by the increase in the length of the alkyl chain which causes a decrease
in proton mobility and greater steric barriers. These factors may influence a decrease in the reactivity of the adhesive mass.
10
Table 2. The effect of assembly time on shear strength and wood failure of three-layer
beech plywood with MUF resin hardened with PILs with different amounts of carbon in alkyl group after tests according to EN 314-01 standard
Tabela 2. Wpływ roboczego czasu klejenia na wytrzymałość na ścinanie i udział ścięcia próbki w drewnie trzywarstwowych sklejek bukowych po testach według EN 314-01 uzyskanych
z żywicy MUF utwardzanej protonowymi cieczami jonowymi z różną liczba atomów węgla
w grupie alkilowej
Shear strength and wood failure
of plywood after tests according
to EN 314-01
Wytrzymałość na ścinanie i udział ścięcia
próbki w drewnie po testach
wg EN 314-01
Type of test
Rodzaj testu
p. 5.1.3.
AW-100
Basic statistics
Statystyki
podstawowe
Hardener type
Typ utwardzacza
Alkyl group PILs
Control
Grupa alkilowa w protonowej cieczy
jonowej
C4H9
Kontrolny
C10H21
NH4NO3
Assembly time (days)
Unit
Roboczy czas klejenia (dni)
Miano
1
30
1
30
01
12
2.05
1.73
1.38
0.23
2.88
2.48
2.01
0.28
2.31
2.01
1.63
0.22
3.01
2.62
1.88
0.39
2.27
1.77
1.39
0.33
13.4
10
11.5
18
11.2
20
15.0
53
18.5
43
xmax.
xavg.
xmin.
δn-1
MPa
3.14
2.32
1.75
0.46
ν
WF
%
19.9
48
xmax. – maximum, xavg. – average, xmin. – minimum, δn-1 – standard deviation, ν��
��
– variation coefficient, WF – wood failure
xmax. – maksimum, xavg. – średnia, xmin. – minimum, δn-1 – odchylenie standardowe, ν – współczynnik
zmienności, WF – zniszczenie w drewnie
1
2
40 min
after 30 days waterproof plywood was not achieved
po 30 dniach nie uzyskano sklejki wodoodpornej
The properties of beech plywood are presented in tables 2, 3 and illustrated
in fig. 3. The plywood types were characterised by very high quality waterproof
glue lines. No effect of the size of the alkyl group on waterproof glue lines was
observed. Rt values were similar and ranged from 2.39 MPa (PIL-butyl) to 2.73
MPa (PIL-hexyl). Slightly higher values of WF were obtained for hexyl and octyl
substituents. The results were similar to those obtained using NH4NO3 as a hardener (control plywood).
The plywood fulfilled the requirements of the EN-314-02 standard in terms
of strength and water resistance of glue lines, regardless of PILs used.
The effects of assembly time on the quality of beech plywood are given in
table 2. We managed to obtain waterproof plywood for variants seasoned for
1 day and 30 days, produced using glue with PIL modifiers. However, in the case
of control plywood we did not achieve waterproof glue lines after 30 days.
Protic ionic liquids as a new hardener-modifier system for melamine-urea-formaldehyde adhesive resins 11
Fig. 2. Gel time at 100°C for MUF resins cured with PILs with different amounts of
carbon atoms in alkyl group
Rys. 2. Czas żelowania w 100°C żywic MUF utwardzanych protonowymi cieczami jonowymi
z różną liczbą atomów węgla w grupie alkilowej
Fig.3. Shear strength (Rt) and wood failure (WF) of three-layer beech plywood with
MUF resin hardened with PILs type with different amounts of carbon in alkyl group after tests on an IF-20 and AW-100 item 5.1.1 and 5.1.3. according to EN 314-01
standard
Rys.3. Wytrzymałość na ścinanie (Rt) i udział ścięcia próbki w drewnie (WF) trzywarstwowych
sklejek bukowych po testach IF-20 and AW-100 p.5.1.1 and 5.1.3 według EN 314-01 uzyskanych z żywicy MUF utwardzanej protonowymi cieczami jonowymi z różną liczbą atomów węgla
w grupie alkilowej
12
To sum up, based on the results of the tests it can be concluded that PILs are
fully useful in plywood manufacturing technologies using MUF resins. They are
interesting compounds, fulfilling the function of modifier and/or hardener of MUF
resin: a phenomenon which has as yet not been described in literature. The relatively low reactivity of studied PILs may be increased by the use of a combined
hardener, i.e. ionic liquid/Lewis acid. Gluing plywood for up to 30 days indicates
a strong possibility of modelling the process and the technology of bonding. Studies have proved that there is great potential in the application of protic ionic liquid as hardeners-modifiers. It seems purposeful to conduct further research on the
use of PILs in wood material technology. The method of synthesis of protic ionic
liquids and their use as a modifier of adhesive amine resins has been submitted for
patent protection.
Summary
Based on the research conducted, it was found that dialkylmethylammonium dodecylbenzenesulfonate base protic ionic liquids made a whole hardener of MUF
resins that could simultaneously perform the function of a modifier, plasticizing
the adhesive glue line. The plywood types obtained were characterised by very
high water resistance and quality of adhesive bonding. They met the requirements
of EN-314-02 standard, for class 3 of gluing quality. The application of protic ionic liquids as amino resin glue hardeners would expand technological capabilities
in plywood manufacturing.
Acknowledgements
This investigation received financial support from project POIG. 01. 03. 01-30074/08 “Ionic liquids in innovative technologies connected with the processing
of lignocellulosic raw materials” co-financed by the European Regional Development Fund under the Innovative Economy Operational Program 2007–2013.
References
Deetlefs M., Seddon K. [2010]: Assessing the greenness of some typical laboratory ionic liquid preparations. Green Chem. 12: 17–30
Han S. H., Li J., Zhu S., Chen R., Wu Y., Zhang X., Yu Z. [2009]: Potential application
of ionic liquids in wood related industries. Bioresources [4]2: 825–834
Jóźwiak M., Proszyk S., Jabłoński W. [2003]: Adhesive melamine-urea-formaldehyde resins
modified with natural alkyloresorcinols. Drewno-Wood [46]:18-30.
Kamoun C., Pizzi A., Zanetti M. [2003]: Upgrading melamine-urea-formaldehyde polycondensation resins with buffering additives. I. The effect of hexamine sulfate and its limits.
J. Appl. Polym. Sci. [90] 1: 203-214
Protic ionic liquids as a new hardener-modifier system for melamine-urea-formaldehyde adhesive resins 13
Kichner B. [2009]: Ionic Liquids. Springer-Verlag Berlin, Heidelberg
Pernak J., Zabielska-Matejuk J., Kropacz A., Foksowicz-Flaczyk J. [2004]: Ionic liquids
in wood preservation. Holzforschung 58: 286–291
Pernak J., Goc I., Fojutowski A. [2005]: Protic ionic liquids with organic anion as wood
preservative. Holzforschung 59: 473–475
Pernak J., Śmiglak M., Griffin S. T., Hough W. L., Wilson T. B., Pernak A., Zabielska-Matejuk J., Fojutowski A., Kita K., Rogers R. D. [2006]: Long alkyl chain quaternary
ammonium-based ionic liquids and potential applications. Green Chemistry 8: 798–806
Pernak J., Jankowska N., Walkiewicz F., Jankowska A. [2008]: The use of ionic liquids
in strategies for saving and preserving cultural artifacts. Polish J. Chem. 82: 2227–2230
Pizzi A. (1994): Advanced wood adhesive technology. Marcel Dekker Inc. New York
Pizzi A., Beaujean M., Zhao C., Properzi M., Huang Z. [2002]: Acetal-induced strength
increases and lower resin content of MUF and other polycondensation adhesives J. Appl.
Polym. Sci. [84] 13: 2561-2571
Proszyk S., Krystofiak T., Jóźwiak M, Lis B. [2002]: Investigations on the strength and durability of glue lines from MUF adhesives at various loading. Proc. of IVth Inter. Symp.
Composite wood materials. TU Zvolen: 219-224
Rogers R. D., Seddon K. R. [2002]: Ionic liquids: Industrial applications for Green Chemistry.
Oxford University Press, New York
Stasiewicz M., Fojutowski A., Kropacz A., Pernak J. [2008]: 1-Alkoxymethyl-X-dimethylaminopyridinium-base ionic liquids in wood preservation. Holzforschung 62: 309–317
Wang S., Pizzi A. [1997]: Waste nylon fibre hardeners for improved adhesives water resistance. Holz a. Rohu.Werkst. [55] : 9195
Wasserscheid P., Welton T. [2008]: Ionic liquids in synthesis, Wiley-VCH
Welton T. [1999]: Room-temperature ionic liquids. Chem. Rev. 99: 2071–2084
Weinstabl A., Binder W.H., Gruber H., Kantner W. [2001]: Melamine salts as hardeners for
urea formaldehyde resins J. Appl. Polym. Sci. [81] 7: 1654-1551
Zabielska-Matejuk J. [2005]: Antifungal properties of new quaternary ammonium compounds in relation to their surface activity. Wood Science and Technology [39]3: 235–243
Zabielska-Matejuk J., Urbanik E., Pernak J. [2004]: New bis-quaternary ammonium and
bis-imidazolium chloride wood preservatives. Holzforschung 58: 292–299
Zanetti M., Pizzi A., Beaujean M., Pasch H., Rode K., Dalet P. [2002]: Acetals-induced
strength increase of melamine-urea-formaldehyde (MUF) polycondensation adhesives. II.
Solubility and colloidal state disruption J. Appl. Polym. Sci. [86] 8 : 1855-1862
Zanetti M., Pizzi A. [2003]: Upgrading of MUF polycondensation resins by buffering additives. II. Hexamine sulfate mechanisms and alternate buffers J. Appl. Polym. Sci. [90]
1:215-226
Zanetti M., Pizzi A. [2004]: Low addition of melamine salts for improved melamine-ureaformaldehyde adhesive water resistance J. Appl. Polym. Sci. [88] 2: 287-292
14
PROTONOWE CIECZE JONOWE JAKO NOWE
UTWARDZACZE - MODYFIKATORY KLEJOWYCH ŻYWIC
MELAMINOWO-MOCZNIKOWO-FOMALDEHYDOWYCH
Streszczenie
Do utwardzania klejowych żywic aminowych stosowane są sole amonowe silnych kwasów nieorganicznych (głównie azotany), siarczany, chlorki (wychodzące z użycia ze
względów ekologicznych), kwasy nieorganiczne oraz organiczne, a także bezwodniki
kwasowe. W celu zwiększenia odporności hydrolitycznej spoin klejowych stosuje się
sole melaminy. W wielu ośrodkach naukowych prowadzone są badania nad uzyskaniem
alternatywnych utwardzaczy, powodujących uplastycznienie i zwiększających odporność
spoiny na działanie czynników zewnętrznych.
W Instytucie Technologii Drewna w Poznaniu, w ramach Projektu nr POIG.01.03.0130/074/08 „Ciecze jonowe w innowacyjnych technologiach związanych z przetwarzaniem surowców lignocelulozowych”, prowadzone są badania nad zastosowaniem cieczy
jonowych do utwardzania – modyfikacji klejowych żywic melaminowo-mocznikowo-formaldehydowych.
Celem badań było sprawdzenie przydatności protonowych cieczy jonowych jako utwardzaczy –modyfikatorów klejowych żywic MUF. Do badan wytypowano protonowe dodecylbenzosulfoniany dialkilometylamoniowe, zaliczane do protonowych cieczy jonowych.
Poszczególne ciecze różniły się liczbą węgli w grupie alkilowej. Wytworzono trzywarstwowe sklejki bukowe utwardzane zastosowanymi protonowymi cieczami jonowymi.
Na podstawie przeprowadzonych badań stwierdzono, że zastosowane protonowe ciecze
jonowe stanowią pełnowartościowe utwardzacze żywic MUF, mogące wypełniać równocześnie funkcję modyfikatora - plastyfikatora spoiny klejowej. Zastosowanie protonowych
cieczy jonowych jako utwardzaczy klejowych żywic aminowych poszerza możliwości
technologiczne w zakresie wytwarzania sklejki. Uzyskane sklejki charakteryzowały się
bardzo wysoką wodoodpornością spoin klejowych i spełniały wymagania EN-314-02.
Słowa kluczowe: żywica klejowa MUF, protonowa ciecz jonowa, system modyfikator-utwardzacz,
sklejka
Xue-Fei Zhou, Jian-Xin Qin, Shu-Rong Wang1
OXIDATION OF A LIGNIN MODEL COMPOUND OF
BENZYL-ETHER TYPE LINKAGE IN WATER WITH H2O2
UNDER AN OXYGEN ATMOSPHERE CATALYZED
BY Co(Salen)
The catalytic properties of Cobalt salen? complex in the oxidation of a lignin model
compound [veratrylglycerol-β-guaiacyl-α,γ-dimethylether, VGD] have been investigated in order to obtain the mechanistic aspects of the reaction between Co(salen) and VGD under an oxygen atmosphere using hydrogen peroxide as an oxidant.
VGD was found to undergo structural changes in response to the catalytic reaction
as characterised by different analytical techniques (FT-IR, H-1 NMR and GC-MS),
yielding 2-methoxy phenol and biphenyl. A mechanism for the oxidation of VGD
was postulated.
Keywords: catalytic oxidation, veratrylglycerol-β-guaiacyl-α,γ-dimethylether
(VGD), Co(salen), FTIR, H-1 NMR, GC-MS
Introduction
Salen complexes are known to be an important class of coordination compounds
that have been used to catalyse an extremely wide variety of reactions over the
past decades since 1933 [Pfeiffer et al. 1933]. Many of these reactions are oxidations of organic substrates, based on the use of terminal oxidants such as molecular oxygen and hydrogen peroxide. Besides being environmentally more benign,
the catalytic oxidation of organic compounds with O2 and H2O2 is less wasteful
from an economic point of view, and is now an important reaction in both research laboratories and industry [Meyer, Limberg 2007]. Metal salen compounds
Xue-Fei ZHOU, Kunming University of Science and Technology; South China University of Technology, Guangzhou; Nanjing University of Technology; Beijing University
of Chemical Technology; Southwest University of Science and Technology, Mianyang,
China
Jian-Xin QIN, Kunming University of Science and Technology, China
Shu-Rong WANG, Zhejiang University, Hangzhou, China.
16
Xue-Fei Zhou, Jian-Xin Qin, Shu-Rong Wang
have been investigated as catalysts in several different reactions, for example
in epoxidation, epoxide ring opening, carbonyl addition, cycloaddition and the
oxidation of sulphides to sulphoxides [Larrow, Jacobsen 2004]. Previous work
on Co(salen)-catalyzed O2-oxidation of p-substituted phenols to p-benzoquinones
has been extended to include substrates that serve as models for lignin phenolic
subunits [Salanti et al. 2010]. Lignin is an aromatic, amorphous, heterogeneous
polymer that represents the second most abundant natural polymeric material on
Earth [Lebo Jr et al. 2001]. It is known that the bulk of lignin in wood consists
of nonphenolic aryl-glycerol-β-O-aryl ether units. Other units, such as phenylcoumaran (β-5), resinol (β-β), and dibenzodioxocins(5-5/β-O-4, α-O-4) are also
present within the lignin macromolecule [Ralph et al. 2000]. Furthermore, lignin
is usually covalently linked to carbohydrates forming a refractory lignin-carbohydrate network [Lowoko et al. 2003].
Our laboratory has been investigating the mechanism of Co(salen) catalysed
oxidation of lignin using isolated lignins and some model compounds as substrates. In this context, we studied the oxidation of another lignin model compound
with special linkage of benzyl-ether type (VGD) as a substrate, using Co(salen)
complex as a catalyst to mimic lignin peroxidase. The mechanism of oxidation
of such a lignin model compound, using Co complexes as catalysts, is largely
unstudied. In the present study, the oxidation of VGD can provide us with information on the reactivity of both the model compound and lignin itself, and assist
in the development of new catalysts for environmentally-friendly pulp bleaching
processes.
Synthesis of cobalt salen complex
Ligand for the complex was synthesised using the standard method [Jacobsen 1993].
Cobalt complex was synthesised by refluxing an EtOH solution of the ligand and 2
eq. of Co(OAc)2•4H2O for 1 h (scheme 1), adding water and filtering out the product.
Scheme 1
Schemat 1
The product was washed successively with water and 80% EtOH. Brownish-black powder was then obtained under vacuum drying, yield 96.92 %. Typical
characteristic absorption peaks were found with FTIR as follows: C-H stretching
vibration (2869-2948 cm-1), C=N stretching vibration [1635 cm-1], C=C stretching
Oxidation of a lignin model compound of benzyl-ether type linkage in water with H2O2...
17
vibration in aromatic ring (1610, 1577, 1498 cm-1), C-H bending vibration (1373
cm-1), C-O in Ar-O bending vibration (1284 cm-1), C-N stretching vibration (1200,
1149 cm-1), Co-N stretching vibration (568 cm-1), Co-O stretching vibration (470
cm-1).
Synthesis of veratrylglycerol-β-guaiacyl-α,γ-dimethylether (VGD)
Guaiacylglycerol-β-guaiacyl (GG) was basically prepared following the procedure proposed by Hosoya et al. [Hosoya et al. 1980], except for cupric bromide
being used instead of Br2 for the preparation of ω-bromo acetoguaiacone from
acetoguaiacone [King, Ostrum 1964; Fukagawa et al. 1992]. GG was methylated
fully with methyl iodide in anhydrous methyl sulfoxide (DMSO) in a nitrogen
atmosphere according to Hakomori method [Hakomori 1964]. See scheme 2. Typical characteristic absorption.
Scheme 2
Schemat 2
Peaks of VGD were found in FTIR and H-1 NMR spectra as follows (fig.
2, 3): C-H vibration in aromatic ring (3030 cm-1), C-H vibration in CH3-, CH2-,
CH- (2937 cm-1), C-H vibration in -CH2- (2841 cm-1), C=C vibration in aromatic
ring (1595, 1503, 1456 cm-1), C-H vibration in CH3- (1369 cm-1), C-O vibration
in β-O-4 linkage (1258 cm-1), C-H stretching in aromatic ring (1147 cm-1), C-O-C at α, γ-position (1076 cm-1), C-H stretching in aromatic ring (1031, 951, 815
cm-1); H-Ar (7.03-6.75 ppm), H-β (4.7-4.5 ppm), H-α (4.4-4.3 ppm), 3-OCH3 and
4-OCH3 (3.9-3.8 ppm), 3′-OCH3 (3.8-3.7 ppm), H-γ (3.7-3.6 ppm), α-OCH3 and
γ-OCH3 (3.6-3.5 ppm).
Oxidation of VGD
30 mg of VGD, 2 mg of catalyst, and 0.48 mg of pyridine were taken in a glass
reactor. 0.6 ml of 30% H2O2 was added drop by drop. Enough NaOH was added
to ensure pH controlled to 12.5 and heated to the reaction temperature in a water
bath. The mixture was stirred under oxygen atmosphere. The reaction was carried
out for 0.5 h at 90°C. At the end of the reaction, the reaction mixture was cooled to
room temperature and then separated with a glass filter to obtain solid and liquid
samples. The isolated solid samples were analysed by FTIR (EQUINOX55) and
18
H-1 NMR (BRUKER DRX500). The liquid samples were extracted into dichloromethane. The extract was dried over Na2SO4, filtered and then the solvent was
evaporated under reduced pressure. The identity of the products, i.e. 2-methoxy
phenol and biphenyl, present in the extract was confirmed by GC-MS (AGILENT
TECHNOLOGIES GC-MS HP6890/5973MS). See table 1 and fig. 1.
Table 1. Identity of the products, i.e. 2-methoxy phenol and biphenyl, by GC-MS
Tabela 1. Określenie produktów, tj. 2-metoksy fenolu i bifenylu, za pomocą GC-MS
No.
Nr
RT
[min]
RSI
SI
1
8.50
919
2
43.03
773
Name
Molecular
formula
Library
Nazwa
Wzór
cząsteczkowy
Biblioteka
910
2-Methoxy phenol
C7H8O2
Mainlib
677
6-Hydroxy-2',3',4'-1,1'-biphenyl
C15H16O4
Mainlib
With the SI and RSI matching factors, a perfect match results in the value of 1000. As a general
guide 900 or greater is an excellent match, 800-900 a good match, and 700-800 a fair match.
Przy dobrze dobranych czynnikach SI i RSI, doskonałe dopasowanie prowadzi do wartości 1000.
Ogólnie przyjmuje się, że 900 lub większa wartość oznacza doskonałe dopasowanie, 800-900 dobre
dopasowanie, a 700-800 dostateczne dopasowanie.
(a)
Compound Structure
Struktura związku
Delta
(b)
Fig. 1. MS spectra of 2-methoxy phenol (a) and biphenyl (b)
Rys. 1. Widma MS 2-metoksy fenolu (a) i bifenylu (b)
Spectrum
Widmo
19
Result and discussion
Oxidative enzymes such as lignin peroxidase (LiP), manganese peroxidase (MnP),
and laccase participate in bioconversions of lignin [Boerjan et al. 2003]. The capability of salen-type metal complexes to function as mimics for those enzymes
was tested by oxidising VGD with H2O2 under oxygen atmosphere catalysed by
a prepared Co(salen) complex. The oxidation was carried out at a temperature
of 90°C in an alkaline aqueous solution at pH 12.5. The reaction was elucidated
with FTIR, H-1 NMR and GC-MS techniques. The structural changes of VGD
across the Co(salen) catalytic oxidation were obtained based on the data (tables
2, 3) from FTIR and H-1 NMR spectra (fig. 2, 3). The functional description
in FTIR and H-1 NMR spectra was determined following the data from Hu [2003]
and Toikka & Brunow [1999], respectively.
Table 2. Structural changes of VGD as determined by FTIR during Co(salen) catalytic oxidation
Tabela 2. Zmiany strukturalne VGD określone za pomocą FTIR podczas katalitycznego utleniania Co(salen)
Wavenumber
No.
Nr
1
2
3
4
5
6
7
Functional description
Opis funkcjonalny
Numer fali
Signal changes in FTIR spectra
Zmiany sygnału w widmach FTIR
VGD after reaction
[cm-1]
VGD
3030
m
w
C-H vibration in CH3-,
CH2-, CH-
2937
m
n
C-H vibration in -CH2-
2841
m
n
1623
n
m
1595, 1503, 1456
s
n
1400
n
s
1369
m
n
C-H stretching in aromatic ring
rozciąganie się C-H w pierścieniu aromatycznym
drgania C-H w CH3-, CH2-,
CHdrgania C-H w -CH2-
C-O vibration in side
chain C=O
drgania C-O w łańcuchu
bocznym C=O
C=C vibration in aromatic
ring
drgania C=C w pierścieniu
aromatycznym
C-H vibration
dragnia C-H
C-H vibration in CH3drgania C-H w CH3-
VGD po reakcji
20
Table 2. Continued
Tabela 2. Ciąg dalszy
8
9
10
11
12
13
C-O vibration in β-O-4
linkage
drgania C-O w wiązaniu
β-O-4
C-O-C vibration at α,
γ-position
drgania C-O-C w pozycji
α, γ
1258
m
n
1147
m
n
1076
m
n
1031
s
n
951
m
n
815
w
n
s – strong; m – medium; w – weak; n – nondetectable
s – silne; m – średnie; w – słabe; n – niewykrywalne
Table 3. Structural changes of VGD as determined by H-1 NMR during Co(salen)
catalytic oxidation
Tabela 3. Zmiany strukturalne VGD określnone za pomocą H-1 NMR podczas katalitycznego utleniania Co(salen)
Chemical shift
No.
Nr
Functional description
Opis funkcjonalny
Przesunięcie
chemiczne
Signal changes in spectra
Zmiany sygnałow w widmach
[ppm]
VGD
VGD after reaction
VGD po reakcji
1
H-Ar
7.03-6.75
s
m
2
H-β
4.7-4.5
ns
ns
3
H-α
4.4-4.3
ns
ns
4
3-OCH3, 4-OCH3
3.9-3.8
s
m
5
3′-OCH3
3.8-3.7
s
m
21
Table 3. Continued
6
H-γ
3.7-3.6
ns
ns
7
α-OCH3, γ-OCH3
3.6-3.5
ns
ns
s – strong; m – medium; ns – not significant
s – silne; m – średnie; ns – nieistotne
(a)
(b)
Fig. 2. FTIR spectra of untreated sample (VGD, a) and treated sample (treated VGD, b)
Rys. 2. Widma FTIR próbki niezmienionej (VGD, a) i próbki zmienionej (zmieniony VGD, b)
22
Fig. 3. H-1 NMR spectra of untreated sample (VGD) and treated sample (treated
VGD)
Rys. 3. Widma H-1 NMR próbki niezmienionej (VGD) i próbki zmienionej (zmieniony VGD)
A clear trend is observed according to the signal changes in the FTIR and
H-1 NMR spectra in tables 1 and 2. The aromatic ring (3030, 1595, 1503, 1456,
1147, 1031, 951, 815 cm-1, 7.03-6.75 ppm) was seriously degraded; carbonyl
(C=O, 1623 cm-1) occurred in the aromatic side chain due to Co(salen) catalytic
oxidation in the presence of H2O2 under oxygen atmosphere. Similarly Kervinen
found that veratryl alcohol, a lignin model compound, could be selectively oxidized to veratraldehyde with molecular oxygen in water catalyzed by Co(salen)
[Kervinen 2005].
Fig. 4. Postulated mechanism for transformation of VGD catalyzed by Co(salen)
Rys. 4. Postulowany mechanizm transformacji VGD katalizowanego Co(salen)
23
Demethylation was observed during the catalytic oxidation based on the signals at
1369, 1076 cm-1 (FTIR), 3.9-3.8, 3.8-3.7 ppm (H-1 NMR). The cleavage of β-O-4
linkage (1258 cm-1) gave 2-methoxy phenol, and C-C coupled biphenyl, a compound arising from radical coupling, was obtained as well, as detected by GC-MS
analysis (table 1, fig. 1), which commonly involves the hydrogen atom abstraction
by the cobalt superoxo complex [Mayer 1998; Mayer et al. 2006]. The mechanism
postulated is given in fig. 4.
Conclusions
VGD, a lignin model compound with benzyl-ether type linkage, was found to
undergo obvious changes in structure during the catalytic reaction by Co(salen)
with hydrogen peroxide under oxygen atmosphere. The reaction of aromatic ring-opening, demethylation and β-O-4 cleavage was observed, yielding 2-methoxy
phenol and biphenyl.
Acknowledgements
The authors are grateful for the financial support of the National Natural Science
Foundation of China (No. 21166011, 20766002), the Scientific Research Foundation of the Department of Education of Yunnan Province (No. 2010J059), the
Open Project of the State Key Laboratory of Clean Energy Utilization of Zhejiang
University (No. ZJUCEU2010004), the Open Project of the State Key Laboratory of Pulp and Paper Engineering of South China University of Technology
(No. 201033), the Open Project of the State Key Laboratory of Materials-Oriented Chemical Engineering of Nanjing University of Technology (No. KL10-12),
the Open Project of the State Key Laboratory of Chemical Resource Engineering
of Beijing University of Chemical Technology (No. CRE-2011-C-305), the Open
Project of the Key Laboratory of Solid Waste Treatment and Resource Recycling
of the Ministry of Education of Southwest University of Science and Technology
(No. 11zxgk07), and the Analysis and Testing Foundation of Kunming University
of Science and Technology.
References
Boerjan W., Ralph J., Baucher M. [2003]: Lignin bios. Ann. Rev. Plant Biol. 54: 519-549
Fukagawa N., Meshitsuka G., Ishizu A. [1992]: 2D NMR study of residual lignin in beech
Kraft pulp combined with selective cleavage with pivaloyl iodide. J. Wood Chem. Technol. 12 [4]: 425-445
Hakomori S. [1964]: A rapid permethylation of glycolipid and polysaccharide catalyzed by
methylsulfinyl carbanion in dimethyl sulfoide. J. Biochem. [55]: 205-208
Hosoya S., Kanazawa K., Kaneko H., Nakano J. [1980]: Synthesis of gaiacylglycerol-βguaiacyl ether (in Japanese). Mokuzai. Gakkaishi 26: 118-121
24
Hu Z. J. [2003]: Degradation of lignin-carbohydrate complexes catalyzed by GIF biomimetic
system (in Chinese). South China University of Technology, Guangzhou
Jacobsen E. N. [1993]: Catalytic Asymmetric Synthesis. VHC, New York
King L. C., Ostrum G. K. [1964]: Selective bromination with copper (II) bromide. J. Org.
Chem. 29: 3459-3461
Kervinen K. [2005]: Studies on veratryl alcohol oxidation catalyzed by Co(salen) type complexes and molecular oxygen in aqueous solution. University of Helsinki
Larrow J. F., Jacobsen E. N. [2004]: Asymmetric processes catalyzed by chiral (salen) metal
complexes. Topics Organomet Chem. 6: 123-152
Lebo Jr S. E., Gargulak J. D., McNally T. J. [2001]. Lignin. In: Kirk-Othmer Encyclopedia
of Chemical Technology. John Wiley and Sons, Hoboken
Lowoko M., Henriksson G., Gellerstedt G. [2003]: New method for the quantitative preparation of lignin-carbohydrate complex from unbleached softwood kraft pulp: Lignin-polysaccharides networks I. Holzforschung 57: 69-74
Mayer J. M. [1998]: Hydrogen atom abstraction by metal-oxo complexes: Understanding the
analogy with organic radical reactions. Acc. Chem. Res. 31: 441-450
Mayer J. M., Mader E. A., Roth J. P., Bryant J. R., Matsuo T., Dehestani A., Bales, B. C.
Watson E. J., Osako T., Valliant-Saunders K., Lam W. H., Hrovat D. A., Borden W.
T., Davidson E. R. [2006]: Stoichiometric oxidations of σ-bonds: Radical and possible
non-radical pathways. J. Mol. Catal. A: Chem. 251 [1-2]: 24-33
Meyer F., Limberg C. [2007]: Organometallic Oxidation Catalysis. Springer-Verlag, Berlin,
Heidelberg
Pfeiffer P., Breith E., Lübbe E., Tsumaki T. [1933]: Tricyclic ortho-condensed partial valence rings. Justus Liebig's Annalen der Chemie 503: 84-130
Ralph J., Marita J., Ralph S., Hatfield R., Lu F., Ede R., Peng J., Quideau S., Helm R.,
Grabber J., Kim H., Jimenez-Monteon G., Zhang Y., Jung H., Landucci L., Mackay
J., Sederoff R., Chapple C., Boudet A. [2000]: Solution-state NMR of lignins. In: Advances in Lignocellulosic Characterization. Argyropoulos D., Rials T., Eds.; TAPPI Press,
Atlanta
Salanti A., Orlandi M., Tolppa E.-L., Zoia L. [2010]: Oxidation of isoeugenol by salen complexes with bulky substituents. Int. J. Mol. Sci. 11: 912-926
Toikka M., Brunow G. [1999]: Lignin-carbohydrate model compounds. Reactivity of methyl
3-O-(α-L-arabinofuranosyl)-β-D-xylopyranoside and methyl β-D-xylopyranoside towards
a β-O-4-quinone methide. J. Chem. Soc., Perkin Trans. L.: 1877-1883
25
UTLENIANIE MODELOWEGO ZWIĄZKU LIGNINY Z TYPEM
WIĄZANIA BENZYLOWO-ETEROWEGO W WODZIE Z H2O2
W ATMOSFERZE TLENU KATALIZOWANE Co(Salen)
Streszczenie
Zbadano katalityczne właściwości kompleksu Co(Salen) w utlenianiu modelowego
związku ligniny (veratrylglycerol-β-guaiacyl-α,γ-dimetyleter, VGD) w celu określenia
mechanicznych aspektów reakcji pomiędzy Co(salen) i VGD w atmosferze tlenu przy zastosowaniu nadtlenku wodoru jako utleniacza. Zaobserwowano, że w VGD zaszły zmiany
strukturalne w odpowiedzi na reakcję katalityczną, co przedstawiono za pomocą różnych
technik analitycznych (FTIR, H-1 NMR oraz GC-MS). W efekcie otrzymano 2-metoksy
fenol i bifenyl.
Słowa kluczowe: utlenianie katalityczne, veratrylglycerol-β-guaiacyl-α,γ-dimetyleter (VGD), Co(salen), FTIR, H-1 NMR, GC-MS
Ladislav Dzurenda, Kazimierz A. Orlowski1
THE EFFECT OF THERMAL MODIFICATION OF ASH
WOOD ON GRANULARITY AND HOMOGENEITY OF
SAWDUST IN THE SAWING PROCESS ON A SASH GANG
SAW PRW 15-M IN VIEW OF ITS TECHNOLOGICAL
USEFULNESS
This paper presents the results of granulometric analyses of sawdust of unmodified
and thermally- modified ash wood (Fraxinus exelsior L.) sawed on a narrow-kerf
sash gang saw. The sawdust of dry thermally-modified ash produced in the sawing
process on a frame sawing machine PRW15-M at a feed speed in the range of
0.36-1.67 m·min-1 has chip granularity ranging from 33.5 µm to 9.9 mm; whereas
unmodified ash wood sawdust consists of chips in a granularity range from 35.6
µm to 13.8 mm. It was observed that thermally-modified ash sawdust is finer, with a
distinctly larger share of the fraction in the granularity range a = 125-500 μm and
a slightly increased share of the fraction in the range a = 32-125 μm. Changes in
mechanical characteristics of modified wood were also observed in the technological usefulness of a part of dry sawdust chip in the granularity range a = 250 μm-2.4
mm. While the homogenous share of chips in sawdust produced in the process of sawing of dry ash wood was HSCha = 81-84 %, the demonstrated homogenous share
of chips in ash sawdust formed in the process of sawing of dry thermally-modified
wood was lower by 4-6 %.
Keywords: ash wood, thermal modification, frame sawing machine, granulometric
analysis, granularity
Introduction
During the sawing process of wood, chip sawdust is produced together with the
main product. The shape, dimensions and amount of chips depend on the form,
physical and mechanical properties of the sawed wood, as well as on the shape,
dimensions, and sharpness of the cutting blade, and technical and technological
Ladislav Dzurenda, Technical University in Zvolen, Slovakia
Kazimierz A. Orlowski, Gdansk University of Technology, Poland
28
Ladislav Dzurenda, Kazimierz A. Orlowski
conditions of the sawing process [Prokeš 1978; Goglia 1994; Lisičan et al. 1996;
Wasielewski 1999; Orłowski 2003; Kopecký, Rousek 2007; Klement, Detvaj
2007; Dzurenda 2007].
Sawdust is characterised as poly-dispersion bulk material consisting of coarse
and medium- coarse fractions [Hejma et al. 1981; Dzurenda 2009], i.e. bulk material with dimensions of grain over 0.3 mm, while the share of fine fractions
with smaller dimensions of chips is not excluded. According to the classification
parameters of bulk material described in STN 26 0070 standard, sawdust is classified as B-45UX, i.e. bulk material of fine granularity (0.5-3.5 mm), hygroscopic,
low crisp and abrasive material with a tendency to crowd.
As a secondary raw material, sawdust has miscellaneous applications. For
example, sawdust is one of the base materials utilised in the production of agglomerated chip materials in the range of granularity 0.25-2.4 mm [Drouet 1992;
Štefka 1997] and also in chemical processing of wood. Moreover, it is a valuable
raw material for energy use by way of direct combustion, and possibly also for
the production of dimensionally and energetically homogenised fuel, for instance
briquettes (type RUF Klasik with dimensions 155×65×95 mm) and industrial type
pellets (with a cylindrical shape of Ø6-8 mm in diameter and a length of 25-30
mm) ��
[Dzurenda, Slovak 2001; ��
Pastorek, Kara, Jevič 2004; Šooš 2005; Dobrowolska et al. 2010].
In recent years, the increasing interest in sawdust as a secondary raw material,
has created the need for a proper specification of the following physical properties: granularity, geometric shapes and dimensions of sawdust chips. The aim
of this work is to analyse the effect of the thermal treatment of ash wood (Fraxinus
excelsior L.) on sawdust granularity in the sawing process conducted on a frame
sawing machine (sash gang saw) PRW15-M, and its technological advantages in
the production of agglomerated chip materials and bio-fuel (pellets and briquets).
Material and methods
The thermal modification of ash was performed in overheated steam in a high
temperature steam dry kiln PW-10 [Hamech 2011] using a technology similar to
ThermoWood technology, in the following conditions presented in fig. 1:
–– intense heating of ash wood up to the temperature of t = 110ºC joined with
drying with wet atmospheric air,
–– overheating of wood in an environment of superheated steam at atmospheric
pressure at a temperature corresponding to conditions of modifications, with
lower intensity than in phase 1., and wood drying,
–– proper process of thermal modification of ash wood at a constant temperature
of t = 197ºC in an environment of superheated steam at atmospheric pressure,
process duration: 4 hours,
The effect of thermal modification of ash wood on granularity and homogeneity of sawdust...
29
–– timber cooling to approximately 80ºC and humidifying by means of water
spraying in order to dampen the atmospheric air,
–– further timber cooling to a final temperature of the process of wood thermal
modification and air conditioning in humid atmospheric air.
Fig. 1. Conditions of thermal modification of ash wood samples
Rys. 1. Warunki modyfikacji termicznej próbek drewna jesionowego
The above described process of thermal modification was similar to the
process of oak wood (Quercus robur L.) modification described in the work by
Dzurenda et al. [2010].
For granulometric analyses, samples of dry ash sawdust (natural, unmodified)
and dry sawdust from thermally-modified ash were taken isokinetically from the
exhaust pipe of a frame sawing machine PRW-15 in accordance with STN ISO
9096 (Manual determination of mass concentration of particulate matter) during
the sawing of modified and unmodified ash wood. Square timber blocks of the
after-planning dimensions of 59.5´59.5´500 mm were sawed at feed speeds of
v1 = 0.36 m·min-1 and v2 = 1.67 m·min-1 on a frame sawing machine PRW15M (table 1) in a laboratory of the Faculty of Mechanical Engineering at Gdansk
University of Technology. The moisture content of ash sawdust wash = 8.3% and
thermally-modified ash wood sawdust wash-M = 8.5% was determined by the weight
method. The technical and technological conditions of sawing are presented in
table 1.
The basic granulometric analyses were done by screening sawdust on a set
of sieves with mesh sizes of 2 mm, 1 mm, 0.50 mm, 0.25 mm, 0.125 mm, 0.080
mm, 0.063 mm, and 0.032 mm, during the time of t = 15 min on an automatic
vibration sieving machine AS 200 (f. RETSCH). The weights of fractions on the
sieves were determined on a set of laboratory scales EP 200 (f. BOSCH) with
a weighting accuracy of 0.001 g.
30
Table 1. Technical data of a frame sawing machine PRW15-M and cutting conditions
during sampling of sawdust
Tabela 1. Dane techniczne pilarki ramowej PRW15-M i warunki skrawania podczas pobierania próbek trocin
Narrow-kerf frame sawing machine PRW15–M
Pilarka ramowa wielpiłowa PRW15–M
Span of the saw frame
Prześwit ramy piłowej
Stroke of the saw sash
Skok ramy piłowej
Max. height of sawn material
Wysokość maksymalna przedmiotu
Min. height of sawn material
Wysokość minimalna przedmiotu
Number of saw blades in the gang during tests
Liczba pił w sprzęgu podczas prób
Overall set (kerf) of the saw blades
Rozwarcie całkowite (rzaz) ostrzy
Cutting edge material
Materiał ostrza skrawajacego
Feed speed
Prędkość posuwu
mm
170
mm
160
mm
150
mm
30
–
5
mm
2
stellit
m·min-1
1.67
0.36
1.67
With a view to specifying details concerning the size of the smallest particles
of fine fraction of dry ash sawdust, a microscopic analysis of granules of dry ash
sawdust fraction was performed. An additional analysis of dry ash sawdust was
carried out by the optical method, i.e. an analysis of the a picture taken under
the microscope Nikon Optiphot-2 with an objective Nikon 4× at the Biometric
Laboratory FLD MZLU in Brno. The granules of sawdust were scanned by 3D TV
CCD camera HITACHI HV-C20 (RGB 752×582 pixels), with a horizontal resolution of 700 TV lines, and evaluated using LUCIA-G 4.0 software (Laboratory
Universal Computer Image Analysis), installed on a PC equipped with a Pentium
90 processor (RAM 32 MB) and a graphic card VGA Matrox Magic, working
under the operating system Windows NT 4.0 Workstation. The software LUCIAG for image analyses enabled us to identify individual particles of disintegrated
wood material, perform quantitative determination of individual particles placed
in the analysed picture and gain basic information, such as the width and length of
the particles, and their circularity, i.e. roundness expressing the degree of deviation of projection-plane of existing grain shape from a projection-plane of round
shape according to the formula:
(1)
where: S is a particle area (m2), and O is a particle perimeter (m).
31
The share of the technologically-useful part of sawdust chips in the range of
granularity equalling a = 250 μm-2.4 mm, according to the methodology for the
determination of homogenous share of chips (HSCh) in sawdust [Dzurenda, Kučerka 2009], is defined by the points of intersection of the lower and upper limit of
the homogenous share of chips on the curve of remainders Za (fig. 2).
Fig. 2. Determination of the share of homogenous granularity of sawdust
Rys. 2. Określanie udziału trocin o jednorodnej ziarnistości (rozdrobnieniu)
Results and discussion
The results of sieve analyses, i.e. granulometric composition of dry sawdust
of unmodified and thermally-modified ash, are presented in tables from 2 to 5.
The granulometric composition of ash sawdust from a frame saw PRW15-M
obtained during cutting at a feed speed of v1 = 0.36 m·min-1 is given in table 2.
Table 2. Granulometric composition of ash sawdust from a frame saw PRW15-M
obtained while cutting at a feed speed of v1 = 0.36 m·min-1
Tabela 2. Skład granulometryczny trocin jesionowych uzyskanych na pilarce ramowej
PRW15-M podczas przecinania z prędkością posuwu v1 = 0.36 m·min-1
Representation of the fractions in dry ash sawdust [%]
Procentowa reprezentacja frakcji w trocinach jesionowych [%]
MSM
[mm]
2.000
1.000
MoF
coarse
gruba
Natural wood (unmodified)
Drewno naturalne
(niemodyfikowane)
Thermally-modified wood
Drewno modyfikowane termicznie
S1
S2
S3
Av.
S1
S2
S3
Av.
3.17
3.21
3.08
3.15
1.91
1.97
1.71
1.86
7.15
7.45
6.74
7.11
1.68
1.77
2.16
1.87
32
Table 2. Continued
0.500
0.250
medium
coarse
średnio
gruba
0.125
0.080
0.063
0.032
fine
miałka
<0.032
35.83
36.15
35.48
35.82
18.13
19.09
18.73
18.65
37.06
35.69
36.68
36.48
55.95
54.98
55.28
55.40
13.10
12.82
13.81
13.24
18.94
17.68
17.51
18.05
2.79
2.88
2.68
2.78
2.48
2.94
3.14
2.86
0.71
0.94
0.92
0.86
0.70
1.04
0.99
0.91
0.20
0.86
0.61
0.56
0.21
0.52
0.48
0.40
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Legend: MSM – measure of sieve mesh, MoF – mark of fraction, S1 – sample #1, S2 – sample
#2, S3 – sample #3, Av. – average value
Legenda: MSM – wymiar oczka sita, MoF – rodzaj frakcji, S1 – próbka nr 1, S2 – próbka nr 2, S3 –
próbka nr 3, Av. – wartość średnia
The largest and the smallest dimensions of particles recognized in dry ash
sawdust from natural (unmodified) and thermally modified ash wood obtained
during sawing on a narrow-kerf frame sawing machine PRW15-M at a feed speed
of v1 = 0.36 m·min-1 are presented in table 3.
Table 3. Areal dimensions of the largest and the smallest chips in examined ash sawdust after sawing at a feed speed of v1 = 0.36 m·min-1
Tabela 3. Wymiary powierzchniowe największych i najmniejszych wiórów w badanych trocinach jesionowych po przecinaniu z prędkością posuwu v1 = 0.36 m·min-1
Timber
Drewno
Unmodified ash
Dimensions of maximal chips [mm]
Wymiary maksymalnych zrębków [mm]
S3
Dimensions of minimal chips [μm]
Wymiary minimalnych zrębków [mm]
S1
S2
S1
S2
S3
3.8 × 12.1
4.1 × 12.4
4.2 × 11.6 35.1 × 35.6 35.8 × 35.9 36.7 × 37.3
Jesion niemodyfikowany
3.1 × 11.7
3.9 × 11.2
3.3 × 10.8 35.6 × 36.3 37.8 × 39.2 37.1 × 38.9
2.8 × 8.6
3.5 × 10.9
2.6 × 9.8
36.2 × 37.8 38.2 × 39.6 37.7 × 41.2
Thermally- modified ash
3,2 × 8.5
3.6 × 8.3
4.9 × 7.9
33.1 × 33.6 33.5 × 33.5 33.7 × 34.3
2.8 × 7.9
3.2 × 7.7
4.7 × 6.9
33.6 × 35.3 37.8 × 39.2 34.1 × 34.9
2.7 × 7.3
2.8 × 6.3
2.2 × 5.7
33.2 × 36.8 38.4 × 39.9 34.7 × 35.2
Jesion modyfikowany termicznie
Table 4 presents the results of sieve analyses concerning granulometric composition of dry sawdust of unmodified and thermally-modified ash after sawing
at a feed speed of v2 = 1.67 m·min-1. Furthermore, the largest and the smallest
dimensions of particles found in dry ash sawdust from natural (unmodified) and
thermally-modified ash wood obtained while sawing on a narrow-kerf frame sawing machine PRW15-M at a feed speed of v2 = 1.67 m·min-1 are given in table 5.
33
Table 4. Granulometric composition of ash sawdust from a frame saw PRW15-M
obtained while cutting at a feed speed of v1 = 1.67 m·min-1
Tabela 4. Skład granulometryczny trocin jesionowych uzyskanych na pilarce ramowej
PRW15-M podczas przecinania z prędkością posuwu v1 = 1.67 m·min-1
Representation of the fractions in dry ash sawdust [%]
MSM
[mm]
2.000
Procentowa reprezentacja frakcji w trocinach jesionowych [%]
MoF
coarse
Natural wood (unmodified)
Drewno naturalne (niemodyfikowane)
Thermally-modified wood
Drewno modyfikowane termicznie
S1
S2
S3
Av.
S1
S2
S3
Av.
2.46
2.90
2.89
2.75
2.41
2.41
2.47
2.43
1.000
gruba
12.21
11.75
12.05
12.00
3.65
4.37
4.99
4.00
0.500
medium
coarse
39.62
41.55
38.74
39.97
38.90
42.64
40.78
40.77
34.00
31.63
33.15
32.93
36.46
33.16
32.97
34.20
9.56
9.43
9,99
9.66
12.47
11.20
13.12
12.26
1.45
1.81
2.18
1.82
5.15
4.97
5.30
5.14
0.51
0.67
0.77
0.65
0.67
0.82
0.99
0,83
0.19
0.25
0.23
0.22
0.29
0.43
0.38
0.37
0.00
0.00
0,00
0.00
0.00
0.00
0.00
0,00
0.250
średnio
gruba
0.125
0.080
0.063
0.032
fine
miałka
<0.032
Legend: MSM – measure of sieve mesh, MoF – mark of fraction, S1 – sample #1,
S2 – sample #2, S3 – sample #3, Av. – average value
Legenda: MSM – wymiar oczka sita, MoF – rodzaj frakcji, S1 – próbka nr 1, S2 – próbka nr 2,
S3 – próbka nr 3, Av. – wartość średnia
Table 5. Areal dimensions of the largest and the smallest chips in examined ash sawdust after sawing at a feed speed of v1 = 1.67 m·min-1
Tabela 5. Wymiary powierzchniowe największych i najmniejszych wiórów w badanych trocinach jesionowych po przecinaniu z prędkością posuwu v1 = 1.67 m·min-1
Timber
Drewno
Dimensions of maximal chips [mm]
Wymiary maksymalnych zrębków [mm]
Dimensions of minimal chips [μm]
Wymiary minimalnych zrębków [mm]
S1
S2
S3
4.2 × 13.8
5.1 × 13.3
3.9 × 12.9
34.5 × 35.8 33.7 × 35.8 35.7 × 36.2
Jesion
niemodyfikowany
3.3 × 13.5
3.8 × 13.6
4.2 × 12.4
35.6 × 37.3 38.8 × 39.9 36.6 × 37.3
2.4 × 10.2
2,9 × 12.3
3.1 × 11.8
38.8 × 41.3 39.9 × 43.6 37.7 × 39.3
Thermallymodified ash
4.2 × 9.9
2.9 × 13.6
3.8 × 8.3
33.3 × 33.8 33.5 × 33.8 33.3 × 34.1
3.8 × 9.6
2.7 × 8.1
4.2 × 8.1
33.4 × 34.6 33.7 × 33.9 35.1 × 36.2
1.6 × 8.9
2.5 × 7.8
2.4 × 6.9
34.8 × 35.5 36.7 × 37.1 35.5 × 36.4
Unmodified ash
Jesion modyfikowany termicznie
S1
S2
S3
Based on the analyses carried out, it can be concluded that the sawdust of dry
thermally modified ash produced in the sawing process on a frame sawing ma-
34
chine PRW15-M at a feed speed in the range of v = 0.36-1.67 m·min-1 consists of
chips of granularity in the range of a = 0.0335-9.9 mm; whereas unmodified ash
wood sawdust consists of chips in the granularity range of a = 0.0356-13.8 mm.
The analyses of size and shape of particles of dry sawdust of both unmodified
and thermally- modified ash demonstrate that most chips fall into the category
of polydispersive fibrils with a strong extension in one dimension. Chips of other
fractions are largely within the category of isometric particles, i.e. particles with
the same dimensions in all three dimensions. The above conclusions result from
the fact that the plan view of chips determined by an optical method is squareshaped and has the value of circularity in the interval of Ψ = 0.7-1.0, and work
under the assumption that the third measure of freely-scattered three-dimensional
objects on a horizontal surface is lower than its largest measure.
The same information on the shape of particles was given by Dzurenda et
al.[2006] in the analysis of pine sawdust particles produced during the sawing
process of dry pine on a frame sawing machine PRW15-M at a feed speed of
v = 0.5-1.5 m·min-1, as well as in the work of Dzurenda et al. [2010] in the case
of the sawing of dry oak and thermally-modified oak wood on a frame sawing
machine PRW-15M.
Fig. 3 presents granularity plots of sawdust obtained during the sawing process of thermally- modified (course a) and unmodified ash wood (course b), with
the highlighted parts of technologically-useful fractions of sawdust chips in the
range from 250 μm to 2.4 mm.
Fig. 3. Residue courses of dry sawdust obtained while sawing on a frame sawing machine PRW15-M, where: a – unmodified ash, b – thermally-modified ash
Rys. 3. Wykresy pozostałości suchych trocin uzyskanych podczas piłowania na pilarce ramowej PRW15-M, gdzie: a – jesion naturalny (niemodyfikowany), b – jesion termicznie modyfikowany
35
The residue courses (fig. 3) and also the sieve analyses results for sawdust
from the sawing processes of unmodified and modified ash wood (tables 2, 4) prove that the sawdust obtained in the sawing process of dry thermally-modified ash
is finer (see that course b is shifted to the left, fig. 3) than the sawdust from unmodified ash. In the sawdust of the thermally-modified wood, the share of moderate
coarse fractions in the range of a = 125-500 μm increased sharply. Furthermore,
there is an increase in the share of fine fraction in the range of granularity a = 32125 μm at the expense of the fraction a = 0.5-2.0 mm. This fact can be attributed
to the increased fragility of thermally-modified ash wood [Mayes, Oksanen 2002;
Reinprecht, Vidholdová 2008]. Similar results, i.e. refinement of chip granularity, were observed during the milling process of thermally-modified beech wood
[Beljo Lučic et al. 2009].
The comparison of dimensional homogeneity allows the observation that the
directly technologically-useful part of sawdust chips in the range of granularity
a = 250 μm-2.4 mm, originating from the sawing process of dry ash wood, was
HSCha = 81-84 % (homogenous share of chips in sawdust); whereas in the case
of sawdust chips originating from the sawing process of dry modified ash wood
that value was lower by 4-6 %.
Conclusions
Based on the analyses carried out, it can be concluded that:
–– firstly, the sawdust of the dry thermally-modified ash, created in the sawing
process on a frame sawing machine PRW15-M at a feed speed of v = 0.361.67 m·min-1, consists of chips of granularity ranging from 33.5 µm to 9.9
mm;��
whereas unmodified ash wood sawdust consists of chips in the granularity range from 35.6 µm to 13.8 mm; in both cases, polydispersive fibrils with
a strong extension in one dimension were observed,
–– secondly, in terms of particle shape, the chips of the largest fraction fall into
the category of fibril bulk materials; whereas the chips of the fine fraction are
in the category of isometric particles,
–– thirdly, thermally-modified ash sawdust is finer, with a distinctly larger share
of the fraction in the granularity range a = 125-500 μm, and a slightly increased share of the fraction in the range a = 32-125 μm, at the expense of the
fraction a = 0.5-2.0 mm,
–– finally, some technological usefulness of sawdust obtained during the sawing
process on a frame sawing machine PRW15-M of both thermally-modified
and unmodified ash wood in the range of granularity a = 250 μm-2.4 mm was
observed; the homogenous share of chips in dry ash sawdust was HSCha =
81-84 %; whereas in ash sawdust produced in the sawing of dry thermallymodified wood, the share was lower by 4-6 %.
36
References
Beljo Lučič R., Čavlovoč A., Dukič I., Jug M., Ištvanič J., Škaljič N. [2009]: Machining
propertirs of thermally modified beech-wood compared to steamed beech-wood. In: Woodworking technique. DENONA, Zagreb: 315-324
Dobrowolska E., Dzurenda L., Jabloński M., Kłosińska T. [2010]: Wykorzystanie energetyczne dendromasy. SGGW, Warszawa
Drouet T. [1992]: Technologia plyt wiórowych. SGGW, Warszawa
Dzurenda L. [2009]: Štruktúra zrnitosti a podiel izometrických triesok v mokrej pilene z procesov pílenia drevana hlavných piliarskych strojoch. Acta Facultattis Xylologiae [51] 2:
55-66
Dzurenda L., Kučerka M. [2009]: Granularity of sawdust from processes of wood sawing
with frame, log band and circular saws. In: Wood machining and processing – product
quality and waste charakteristics. WULS-SGGW, Warszawa: 96-115
Dzurenda L., Slovák J. [2001]: Energetické vlastnosti peliet vyrobených zo smrekovej piliny.
In: Acta Mechanica Slovaca [5] 3: 201 - 206
Dzurenda, L. [2007]: Sypká drevná hmota, vzduchotechnická doprava a odlučovanie. V-TU,
Zvolen
Dzurenda L., Wasielewski R., Orlowski K. [2006]: Granulometric analysis of dry saw-dust
from sawing process on the frame sawing Machine PRW-15M. Acta Facultatis Xylologiae
[48] 2: 51-57
Dzurenda L., Orlowski, K., Grzeskiewicz M. [2010]: Effect of Thermal Modification of Oak
Wood on Sawwdust Granularity. Drvna Industrija Journal [61] 2: 89-94
Goglia, V. [1994]: Strojevi i alati za obradu drva I. GRAFA, Zagreb
Hamech [2011]: Parzelnia wysokotemperaturowa PW10 http://www.hamech.pl/wysokotemperaturowa_parzelnia_drewna_PW,p,90.html
Hejma J. et al. [1981]: Vzduchotechnika v dřevozpracovávajícím průmyslu. SNTL, Praha
Klemet I., Detvaj J. [2007]: Technologia prvostupňového spracovania dreva. V-TU, Zvolen
Kopecký Z., Rousek M. [2007]: Dustiness in high-speed milling. Wood Research [52] 2: 65-76
Lisičan J. et al. [1996]: Teória a technika spracovania dreva. Matcentrum, Zvolen
Mayes D., Oksanen O. [2002]: Thermo Wood® Handbok. Stora Enso Timber, Finnforest
Orlowski K. [2003]: Materiałooszczędne i dokładne przecinanie drewna piłami. Politechnika
Gdańska, Gdańsk
Pastorek Z., Kára J., Jevič P. [2004]: Biomasa obnovitelný zdroj energie. FCC Public, Praha
Prokeš S. [1978]: Obrábění dřeva a novych hmot ze dřeva. SNTL, Praha
Reinprecht L., Vidholdová Z. [2008]: Termodrevo – príprava, vlastnosti a aplikácie. V-TU,
Zvolen
Šooš Ľ. [2005]: Výskum zhusťovania nových druhov biomateriálov. In: Energetika a životní
prostředí. VŠB-TU, Ostrava: 159-163
Štefka V. [1997]: Kompozitné drevné materiály II. V-TU, Zvolen
Wasielewski, R. [1999]: Pilarki ramowe z eliptyczną trajektorią prowadzenia pil i hybrydowym wyrównoważonym układem napędu głównego. Politechnika Gdańska, Gdańsk
37
WPŁYW MODYFIKACJI TERMICZNEJ DREWNA
JESIONOWEGO NA ZIARNISTOŚĆ I JEDNORODNOŚĆ
TROCIN Z PROCESU PRZECINANIA NA PILARCE RAMOWEJ
WIELOPIŁOWEJ PRW15-M W ASPEKCIE ICH PRZYDATNOŚCI
TECHNOLOGICZNEJ
Streszczenie
Przedstawiono wyniki analiz granulometrycznych trocin, drewna jesionowego niemodyfikowanego (Fraxinus exelsior L.) i modyfikowanego termicznie, otrzymanych w procesie przecinania drewna na pilarce ramowej wielopiłowej PRW15-M. Przecinanie drewna prowadzono dla dwu prędkości posuwu 0,36 m·min-1 oraz 1,67 m·min-1. Ziarnistość
powstających trocin dla drewna jesionowego modyfikowanego termicznie zawierała się
w przedziale od 33,5 ��
µ��
m do 9,9 mm, podczas gdy dla drewna niemodyfikowanego ziarnistość trocin mieściła się w przedziale od 35,6 ��
µ��
m do 13,8 mm. Stwierdzono, iż trociny otrzymywane z drewna modyfikowanego termicznie są bardziej miałkie, z większym
udziałem frakcji o ziarnistości w przedziale a = 125 – 500 μm, z nieznacznie większym
udziałem frakcji z zakresu a = 32 – 125 μm. Zaobserwowano również, że przydatność
technologiczna trocin mieszczących się w zakresie ziarnistości a = 250 μm – 2.4 mm dla
drewna jesionowego niemodyfikowanego termicznie zawiera się w przedziale 81 – 84 %,
zaś dla drewna jesionowego modyfikowanego termicznie jest mniejsza o około 4 – 6%.
Słowa kluczowe: drewno jesionowe, modyfikacja termiczna, pilarka ramowa wielopiłowa, analiza
granulometryczna, ziarnistość
Iwona Frąckowiak, Franciszek Warcok, Dorota Fuczek, Cezary
Andrzejak1
THE INFLUENCE OF UF MOLAR RATIO ON SELECTED
PARTICLEBOARD PROPERTIES
This paper presents the preliminary research results of a project whose main
objective is to quantify the impact of formulations and technological parameters on formaldehyde content in and emission from particleboards produced
using urea-formaldehyde resin with a low molar ratio of F/U. The formaldehyde content reduction is possible by using a resin with a molar ratio of F/U
of 1.065 hardened with 3% solution of urea and ammonium nitrate or a resin
with a molar ratio of F/U of 0.96 to which 3% urea was added. For these
variants, reductions by 22% and 21% respectively of formaldehyde content in
particleboards were obtained, while at the same time, strength properties that
meet the requirements of the EN-312: 2011 standard for P2 particleboards were
maintained.
Keywords: particleboard, UF, molar ratio, urea
Introduction
In recent decades the content of formaldehyde in and its emission from wood-based panels has been the subject of intensive research [Hse 1974; Kanter 2008;
Harmoan 2008] focusing mainly on developing methods for testing the content
and emission of formaldehyde, understanding the factors affecting formaldehyde
emission from panels [Nemil, Ozturk 2006], and how to reduce the release of this
component during production, as well as the use of the boards [Schäfer, Roffael
2000]. In 2004, the International Agency for Research on Cancer (IARC) identiIwona Frąckowiak, Wood Technology Institute, Poznan, Poland
Franciszek Warcok, Pfleiderer Silekol Sp. z o.o., Poland
Dorota Fuczek, Wood Technology Institute, Poznan, Poland
Cezary Andrzejak, Wood Technology Institute, Poznan, Poland
40
Iwona Frąckowiak, Franciszek Warcok, Dorota Fuczek, Cezary Andrzejak
fied formaldehyde as carcinogen which contributed to stricter requirements for
minimal permissible emission of this component from wood-based panels [Marutzky 2004; Ruffing et al. 2011]. The consequence was a new perspective on the
problem of formaldehyde presence in wood-based panels.
In Europe over 90% of wood-based panels are produced with amino resins,
which are the main source of formaldehyde emission in the production process as
well as from the finished product [Warcok 2007]. Through extensive research and
the involvement of resins and boards producers, over the decades formaldehyde
emission from wood-based panels has been reduced by 80 – 90% in relation to the
values characterizing panels produced in the 1970s [H’ng et al. 2011]. New resins
based on renewable raw materials such as soy, lignin, and tannin, have thus far
not found broad application in the industry due to their high price [Properzi et al.
2008]. Therefore, several projects have been conducted with the aim of reducing
formaldehyde content in wood-based panels, for example by the modification of
amino resins or altering the technological parameters [Tsapuk 1992; Abdullah,
Park 2010; Özalp 2010]. One of the most popular and cheapest methods of formaldehyde emission reduction is the lowering of the molar ratio of urea to formaldehyde (F/U) [Deppe, Ernst 2000; Park et al. 2005; Frąckowiak 2006; Quea
et al. 2007]. Frequently, in order to meet the requirements of E1 class, resins with
a molar ratio of 1.10:1.00 in the case of particleboard, and 1.00:0.85 for MDFs
and HDFs are used [Warcok 2007]. Not so long ago reaching this level of molar
ratio seemed impossible. After an extensive review of literature, Myers [1984]
suggested that using resin with a 1.2 molar ratio of F/U decreases the strength
properties of board below the permissible values and deteriorates adhesive joint
resistance to water. The above-mentioned problems have already been overcome by more reactive hardeners, UF resin modification with melamine [Hse et al.
2008] or phenol, or through increasing the share of resin in the board. Changes
in particleboard manufacturing (the use of particles with proper geometry and low
moisture, the precise removal of dust from particles, the use of precision dispensing systems etc.) together with the optimization of adhesive technology [Rusak,
Warcok 1997] currently allow the use of resins with molar ratio of F/U below 1.0.
This paper presents the preliminary research results of a project whose main
objective is to quantify the impact of formulations and technological parameters
on formaldehyde content in and emission from particleboards produced using
urea-formaldehyde resin with a low F/U molar ratio.
In order to further reduce the content of formaldehyde in particleboard urea,
formaldehyde as the most commonly used sorbent affecting the processes of gelation and resin curing [Jóźwiak 2005], was added to low molar ratios of F/U
resin (1.065 – 0.84). The study aims to determine how much formaldehyde content
can be reduced in particleboards using a resin with low molar ratio and with the
addition of urea, while at the same time maintaining the other properties at the
appropriate level.
41
Wood
Chips from pine wood obtained from sawmill waste were used as raw material.
The wood material was reduced to the desired size with a Pallmann’s chipper.
For particleboard production, the particles passing through a sieve with a mesh
8.0 mm in diameter and remaining on a sieve with a mesh 2.0mm in diameter were
used. The formaldehyde content (EN 120: 1994) in chips with a moisture content
of 0.4% was 0.3 mg/100g of oven dry board (o.d.b.). To produce particleboard,
particles with a moisture content of 2% ± 0.2% were used.
Chemicals
In order to produce particleboards, three types of urea-formaldehyde resins with
different molar ratios of U/F, i.e. 1.065, 0.96, and 0.84, were used. The resin properties are presented in table 1.
In the experiment, two types of hardeners were used: ammonium nitrate
(NH4NO3; concentration 30%) and urea ammonium nitrate solution (the share
of urea in the dry weight of adhesive was 2.3%, the share of ammonium nitrate
in relation to the dry weight of adhesive was 3%). Depending on the research variant, urea was added to the resin to the amounts of 2, 3, and 5%.
Table 1. Resin properties
Tabela 1. Właściwości żywic
F/U molar ratio
Properties
Właściwości
Concentration [%]
Stężenie [%]
Free formaldehyde content [%]
Zawartość wolnego formaldehydu
Gel time at 100 ° C with 2% addition of ammonium
nitrate [s]
Czas żelowania przy 100 °C z 2% dodatkiem
azotanu amonu [s]
Gel time at 100 ° C with 3% addition of urea and
ammonium nitrate solution [s]
Czas żelowania przy 100 °C z 3% dodatkiem
roztworu saletrzano-mocznikowego [s]
Stosunek molowy F/U
1.065
0.96
0.84
66.0
67.3
68.5
<0.2
<0.2
<0.2
80
79
79
67
65
79
42
The parameters of particleboard production
Twelve one-layer particleboards with dimensions of 500 × 700 × 16 mm and a target density of 660 kg/m3 were produced. The particleboards were manufactured
according the following parameters: pressing pressure – 20.5 MPa, pressing temperature – 210 °C, resination – 9%, pressing time – 5 [s/mm], hardener amount
– 2-3% of ammonium nitrate or urea and ammonium nitrate solution, paraffin
amount – 0.4% (concentration 65%). The chemicals were dosed in relation to the
dry weight of resin, and paraffin to the dry weight of wood.
The panels produced were tested for bending strength (EN 310), internal bond
strength perpendicular to the plane of the board (EN 319), and formaldehyde content (EN 120).
The research variants are given in table 2.
Table 2. The research variants and results
Tabela 2. Warianty oraz wyniki badań
F/U
molar
ratio
Hardener type
and amount
1.065
ammonium
nitrate 2%
Stosunek
molowy
F/U
1.065
1.065
1.065
0.960
Typ i rodzaj
utwardzacza
azotan
amonu 2%
ammonium
nitrate 3%
azotan
amonu 3%
urea and ammonium nitrate
solution 2%
roztwór saletrzano-mocznikowy
2%
solution 3%
3%
ammonium
nitrate 2%
azotan
amonu 2%
Urea
addition
[%]
Formaldehyde content Internal
Modulus
Bending
after calculations into
of
bond
strength
humidity value of 6.5% [N/mm2]
elasticity
2
[N/mm ]
Wytrzy(mg/100g o. d. b.)
[N/mm2]
Wytrzy-
Dodatek Zawartość formaldehydu małość na
Moduł
małość na
mocznika
rozciągapo przeliczeniu na
sprężystozginanie
[%]
nie
wilgotność 6,5%
ści
[N/mm2]
[N/mm2]
(mg/100g o. d. b.)
[N/mm2]
-
5.9
0.54
(0.028)
15.3
(0.49)
3003
(117.1)
-
4.1
0.62
(0.022)
9.8
(0.98)
2323
(56,8)
-
5.2
0.60
(0.037)
13.5
(1.21)
3500
(189.3)
-
3.2
0.39
(0.060)
15.1
(0.70)
3038
(174.0)
-
3.9
0.47
(0.026)
13.7
(1.36)
2593
(260.6)
43
Table 2. Continued
0.960
0.840
0.840
1.065
1.051*
1.065
1.025*
1.065
1.000*
0.960
0.948*
0.960
0.925*
0.960
0.902*
solution 2%
2%
ammonium
nitrate 2%
azotan
amonu 2%
solution 2%
2%
ammonium
nitrate 2%
azotan
amonu 2%
ammonium
nitrate 2%
azotan
amonu 2%
ammonium
nitrate 2%
azotan
amonu 2%
ammonium
nitrate 2%
azotan
amonu 2%
ammonium
nitrate 2%
azotan
amonu 2%
ammonium
nitrate 2%
azotan
amonu 2%
-
2.8
0.33
(0.030)
12.3
(0.60)
2766
(205.0)
-
2.3
0.28
(0.022)
11.0
(0.81)
2354
(195.1)
-
1.7
-
-
-
1.0
5.3
0.53
(0.028)
13.9
(0.67)
2341
(132.4)
3.0
4.4
0.51
(0.040)
15.7
(0.97)
2980
(129.0)
5.0
3.5
0.44
(0.030)
16.0
(0.86)
3040
(186.0)
1.0
3.9
0.45
(0.021)
14.2
(1.08)
2501
(83.1)
3.0
3.1
0.42
(0.040)
14.4
(0.98)
2790
(119.0)
5.0
2.7
0.35
(0.030)
12.0
(0.80)
2800
(127.0)
*Real molar ratio of F/U after the addition of urea to the resin
*Faktyczny stosunek molowy F/U po dodaniu mocznika do żywicy
( ) Standard deviation
( ) Odchylenie standardowe
44
In the analyzed molar ratio range, i.e. 1.065-0.84, the formaldehyde content varied
from 5.9 to 1.7 mg/100 g o.d.b., respectively. The value of the coefficient of determination for the tested correlation was 0.989. This study confirmed the known
correlation between the molar ratio of F/U of the resin used and the formaldehyde
content in boards (fig. 1). Based on the data shown in the following figures, it was
calculated that reducing the formaldehyde content in boards produced according
to the established technological parameters to a level close to that characteristic
of natural wood, i.e. below 1 mg/100 g o.d.b., would require a reduction in the
resin molar ratio to 0.76.
Fig. 1. The correlation between the molar ratio F/U of the resin and the content of
formaldehyde in the boards
Rys. 1. Zależność miedzy stosunkiem molowym F/U stosowanej żywicy i zawartością formaldehydu w płytach
As expected, the molar ratio of the resin also had a relevant influence on the
resistance of the boards revealed in the internal bond strength, bending strength,
and modulus of elasticity (fig. 2, 3).
The coefficients of determination for the correlation between molar ratio of
the resin and resistance of the boards were close to 1, similar to the case of formaldehyde.
The strength of the boards in the above-mentioned range was only in accordance with the requirements of the EN-312: 2011 standard when resins with molar
ratios of 1.065 and 0.96 were used.
The boards with the resin of a molar ratio of 0.84 met the requirements only
in the case of modulus of elasticity at static bending.
45
Fig. 2. The correlation between the molar ratio F/U of the resin and the bending
strength and modulus of elasticity
Rys. 2. Zależność miedzy stosunkiem molowym F/U stosowanej żywicy i wytrzymałością na
zginanie oraz modułem sprężystości przy zginaniu statycznym płyt
Fig. 3. The correlation between the molar ratio F/U of the resin and the internal bond
strength of the boards
Rys. 3. Zależność miedzy stosunkiem molowym F/U stosowanej żywicy i wytrzymałością na
rozciąganie płyt
Based on the regression equations it was calculated that the panels produced
according to the established parameters would have an internal bond strength and
46
a static bending strength consistent with the currently applicable European standards when using a resin with a molar ratio of not less than 0.89.
In the light of these results and calculations, no further tests on the resin of
molar ratio of 0.84 were performed. Instead the research focused on the modification of other resins.
In order to further reduce formaldehyde, urea or urea ammonium nitrate solution, which is also a resin hardener, were added to the resins with molar ratios of
1.065 and 0.96. The results of urea addition to the resins to the amounts of 1, 3,
and 5% are shown in Fig. 4 and 5. The application of resins with a low F/U molar
ratio modified by the addition of urea caused the deterioration of the internal bond
strength of the tested panels and, as expected, a reduction in the formaldehyde
content in the particleboards (fig. 6).
Fig. 4. The effect of urea addition to the resin with the F/U molar ratio of 1.065 on the
internal bond strength of the boards and the formaldehyde content
Rys. 4. Wpływ dodatku mocznika do żywicy F/U 1,065 na wytrzymałość na rozciąganie płyt
oraz zawartość formaldehydu
A 5% addition of urea to the resin of F/U molar ratios of 1.065 and 0.960 contributed to a reduction in the formaldehyde content by 34% and 31%. The study
proved that less than 5% of urea can be added to the resin with a F/U molar ratio
of 0.960, because it is probable that an urea addition of 5% or more would result
in a tensile strength reduction below the limit values which are standard for this
type of panels.
Not without significance was the way the urea was dosed to the UF resin. The
study proved that the use of urea and ammonium nitrate solution at 3% in relation
to the dry weight of the resin has a similar effect on the reduction of formaldehyde
in the particleboard as the addition of 5% of urea in the case of the resin cured with
ammonium nitrate (table 2).
47
Fig. 5. The effect of urea addition to the resin with the F/U molar ratio of 0.960 on the
internal bond strength of the boards and the formaldehyde content
Rys. 5. Wpływ dodatku mocznika do żywicy F/U 0,960 na wytrzymałością na rozciąganie płyt
oraz zawartość formaldehydu
A change of hardener from ammonium nitrate to urea and ammonium nitrate
solution resulted in a reduction by approximately 22% of the formaldehyde content in the particleboard made from the resin with a F/U molar ratio of 1.065.
Conclusions
These studies present two answers to the question of to what extent formaldehyde
can be reduced using unmodified urea-formaldehyde resin with a low molar ratio
and the addition of urea, while at the same time maintaining the other properties of
the particleboard at the appropriate level. The first solution relates to the resin with
a molar ratio of F/U of 1.065 hardened with a 3% solution of urea and ammonium
nitrate, and the second to the resin with a molar ratio of F/U of 0.96 to which 3%
urea was added. For these variants, reductions in formaldehyde content in the
particleboard by 22% and 21% were obtained, while at the same time maintaining
the strength properties that meet the requirements of the EN-312:2011 standard
for P2 particleboards. An addition of urea to the panels with the resin hardened
with ammonium nitrate reduces the tensile strength to a lesser extent than in the
case of urea ammonium nitrate solution.
Acknowledgements
This research was financially supported by the Polish Ministry of Science
and Higher Education, project number NN309078338.
48
References
Abdullah Z. A., Park B. D. [2010]: Influence of acrylamide copolymerization of urea–formaldehyde resin adhesives to their chemical structure and performance. Journal of Applied
Polymer Science [117] 6: 3181–3186
Deppe H.J., Ernst K. [2000]: Tashenbuch der spanplattentechnik, 4. überarbeitete und erweiterte Auflage, DRW-Verlag Weinbrenner GmbH & Co., Leinfelden-Echterdingen
Frąckowiak I. [2006]: Wpływ stosunku molowego żywicy mocznikowo-formaldehydowej na
właściwości płyt aglomerowqnych z odpadowych surowców lignocelulozowych. ��
DREWNO-WOOD [49] 175: 71-86
H’ng P. S., Lee S.H., Loh Y. W., Lum W. C. Tan B.H. [2011]: Production of low formaldehyde emission particleboard by using new formulated formaldehyde based resin. Asian
Journal of Scientific Research 1-7
Harmoan D. [2008]: Advances In Ultra-Low Emitting UF Resin Solution For particleboard,
MDF and Hardwood Plywood. Proceedings of the International Panel Products Symposium, 24 -26 September, Espoo
Hse C. Y., Fu F., Pan H. [2008]: Melamine-modified urea Formaldehyde resin for bonding
particleboards. Forest Products Journal 58: 56-61
Hse Chung-Yun [1974]: Characteristics of urea-formaldehyde resin as related to glue bond
quality of southern pine particleboard. Journal of the Japan Wood Research Society [20]
10: 483-490
Jóźwiak M., Proszyk S., Jabłoński W. [2005]: Oddziaływanie mocznika na przebieg procesu
utwardzania i stopień usieciowienia klejowych żywic melaminowo-mocznikowo-formaldehydowych. [48] 174: 31-40
Kanter W. [2008]: Adhesive developments concerning formaldehyde in Europe. Technical
Formaldehyde Conference. Hanower
Marutzki R., Ranat L. [1979]: Die Eigenschaften formaldehydedarmer HF-Leimharze und
daraus hergestellter Holzspanplatten. Holz als Roh-und Werkstoff 10: 303-307
Marutzky R., Dix B. [2004]: Adhesive related VOC – and formaldehyde emissions from
wood products: Test, regulations, standards, future developments. Proceedings of the
COST E34 Conference, Innovations in Wood Adhesive, November 4, Switzerland: 91-106
Mihailova J., Ivanov K., Yordanova S. [2007]: Some Possibilities for reduction of formaldehyde emission from particleboards. COST Action E49 Conference “ Measurement and
control of VOC emissions from wood-based panels. November 28-29, Braunschweig
Myers E. G. [1984]: How molar ratio of UF resin affects formaldehyde emission and other
properties: A literature critique. Forest Product Journal [34] 5: 35-41
Nemil G., Ozturk I. [2006]: Influence of some factors on the formaldehyde content of particleboard. J. Build. Environ. 41: 770-774
Özalp M. [2010]: The effect of borax pentahydrate addition to urea formaldehyde on the
mechanical characteristics and free formaldehyde content of medium density fiberboard
(MDF) Eur. J. Wood Prod. 68:117–119
Park B. D., Kang E. Ch., Park J. Y. [2005]: Effects of Formaldehyde to Urea Mole Ratio on
Thermal Curing Behavior of Urea–Formaldehyde Resin and Properties of Particleboard
Journal of Applied Polymer Science [101] 3: 1787-1792
Properzi M, Jones D., Frihart C. [2008]: Bonding of Timber. WG 3 –Timber and wood bonding process. COST Action E34: 54 Short Core Document
Quea Z., Furunoa T., Katoha S., Nishinob Y. [2007]: Effects of urea–formaldehyde resin
mole ratio on the properties of particleboard. Building and Environment [42] 3: 1257-1263
49
Ruffing T. C., Shi W. W., Brown N. R., Smith P. M. [2011]: Review of united states and international formaldehyde emission regulations for interior wood composite panels. Wood
and Fiber Science [43] 1: 21-31
Rusak W., Warczok F. [1997]: Postęp w rozwoju produkcji żywic klejowych dla potrzeb
przemysłu drzewnego w Zakładach Azotowych „Kędzierzyn” S.A. Biul. Inf. OBRPPD
Schäfer M., Roffael E. [2000]: On the formaldehyde release of wood. Holz als Roh-und Werkstoff 58: 259-264
Tsapuk K. A. [1992]: About the possibility of producing wood particle boards with extremely
low formaldehyde content. Holz als Roh- und Werkstoff 50: 387-388
Warcok F. [2007]: Nowe trendy w produkcji środków wiążących w świetle wymagań Unii
Europejskiej dotyczących emisji formaldehydu. BIOBR 1-2: 35-42
List of standards
PN EN 310:1994 Płyty drewnopochodne. Oznaczanie modułu sprężystości przy zginaniu
i wytrzymałości na zginanie.
PN EN 319:1999 Płyty wiórowe i płyty pilśniowe. Oznaczanie wytrzymałości na rozciąganie
w kierunku prostopadłym do płaszczyzn płyty.
PN EN 120:1994 Tworzywa drzewne. Oznaczanie zawartości formaldehydu. Metoda ekstrakcyjna, zwana metodą perforatora.
PN-EN 312:2011 Płyty wiórowe -- Wymagania techniczne.
WPŁYW STOSUNKU MOLOWEGO ŻYWICY UF NA WYBRANE
WŁAŚCIWOŚCI PŁYT WIÓROWYCH
Streszczenie
Przedstawiono wyniki badań pierwszego etapu projektu, którego głównym założeniem
jest próba kwantyfikacji wpływu receptur i parametrów technologicznych na zawartość
i emisję formaldehydu z płyt wiórowych wytwarzanych z zastosowaniem żywicy mocznikowo-formaldehydowej o niskim stosunku molowym F/U. Spośród przeprowadzonych
badań wybrano dwa optymalne warianty. Pierwszy dotyczy żywicy o stosunku molowym
F/U 1,065 utwardzanej roztworem saletrzano-mocznikowym w ilości 3%, drugi żywicy
o stosunku molowym F/U 0,96 utwardzanej azotanem amonu dodanego w ilości 2%
w stosunku do suchej masy kleju, do której dodano 3% mocznika. W obydwu wariantach
uzyskano obniżenie zawartości formaldehydu w płycie odpowiednio o 22% oraz 21%
przy jednoczesnym zachowaniu właściwości wytrzymałościowych spełniających wymagania normy EN-312: 2011 dla płyt wiórowych klasy P2.
Słowa kluczowe: płyta wiórowa, UF, stosunek molowy, mocznik
Agata Stachowiak-Wencek, Włodzimierz Prądzyński 1
EMISSION OF VOLATILE ORGANIC COMPOUNDS (VOC)
FROM WATERBORNE LACQUERS WITH DIFFERENT
CONTENT OF SOLIDS
This paper presents the results of investigations on the emission of volatile organic
compounds (VOC) from oak wood surfaces finished with acrylic waterborne lacquers. The lacquers selected for the experiments were characterised by a different
content of solids, fluctuating between 32 and 38%. The volatile organic compounds were analysed using a gas chromatography technique combined with mass
spectrometry and thermal desorption (GC/MS/TD). Tenax TA was employed as an
adsorption medium. The obtained results indicate that volatile organic compound
emissions from the experimental waterborne lacquers varied widely from 388 to
1794 µg/m3. The most important constituents of emissions included compounds that
belonged mainly to glycol ethers as well as aliphatic and aromatic hydrocarbons.
Keywords: waterborne lacquers, volatile organic compounds (VOC), gas chromatography with mass spectrometry and thermal desorption (GC/MS/TD)
Introduction
Surface finishing of wood and wood-based materials with various lacquers has
been applied for many years now. Among other things, this kind of finishing
is to used in order to give the above-mentioned products the required decorative-aesthetic appearance, to protect them against the destructive influence of
external factors, and to ensure their long-term service life. Lacquer application,
depending on the type of applied lacquers and the techniques used to apply them,
may have a different impact on the natural environment and the microclimate
of production halls. Major environmental hazards resulting from lacquer application are connected with organic solvents, whose main task is to give lacquers
specific application properties. Most organic solvents are qualified as toxic substances, dangerous due to their volatility as well as ability to dissolve in fats.
Agata Stachowiak-Wencek, Poznan University of Life Sciences, Poland
[email protected]
Włodzimierz Prądzyński, Poznan University of Life Sciences, Poland
[email protected]
52
Agata Stachowiak-Wencek, Włodzimierz Prądzyński
Their properties are such that organic substances emitted from solvents may be
absorbed by the skin, mucous membranes or the gastrointestinal tract and cause
headaches, dizziness, nausea, severe poisoning and even have depressing or narcotic effects.
The current legislation concerning limitations of air pollution obliges manufacturers to produce lacquer articles which are characterised by reduced concentrations of organic solvents. Among the most important, environmentally-friendly
lacquering systems meeting current legislative requirements are products based
on waterborne binders. Until recently, it seemed that waterborne lacquers would
never threaten solvent products. In the case of the wood industry, the application
of waterborne lacquers was frequently connected with a number of different problems, e.g. formation of milky, non-transparent coatings, so-called orange-peel
effect, long drying periods or improper wood structure exposure [Lurka 2007].
Once the above-mentioned drawbacks were eliminated, a growing interest in this
group of articles has been observed.
At present, the manufacturers of lacquers offer a wide range of different products, especially of waterborne articles, of various properties and of different
chemical composition intended for wood and wood-based materials. Waterborne
materials manufactured on the basis of acrylic dispersions are among quite popular and frequently-employed lacquers. Some of their numerous advantages which
deserve a mention are: resistance to atmospheric factors, good adhesion, coating
colour stability, resistance to water and to UV radiation.
It is widely believed that waterborne lacquers are completely safe for the health. Unfortunately, this opinion is incorrect. These products contain resins, pigments, fillers, as well as many other essential aiding agents that are not entirely
neutral for the environment. In addition, they also contain certain quantities (5 to
15%) of organic solvents [Asendorf 1996; Proszyk 2007] that are added, inter alia,
to reduce a minimum temperature of film formation, facilitate the coalescence of
dispersion particles, obtain good fluidity, regulate drying time, and improve rheological properties. Nevertheless, solvents used in waterborne materials are less
noxious, because most frequently they belong to the group of glycols, polyglycols, higher alcohols, etherglycols and their esters [Kuczyńska 2005].
Experiments carried out by research centres proved that the application of
waterborne lacquers made it possible to considerably reduce the use of harmful
emissions in comparison with materials containing solvents [Scheithauer, Aehlig
1995; Salthammer 1997; Dziewanowska-Pudliszak 2007].
Nonetheless, in this group of waterborne lacquers as well, it is necessary
to compare their impact on indoor air quality and indicate systems that are the
safest both for the natural environment and the health of users. The aim of the
investigations carried out was to recognise the effect on the environment of waterborne materials used in the wood industry which are manufactured on the basis
of acrylic dispersions and contain different quantities of solids.
53
Emission of volatile organic compounds (VOC) from waterborne lacquers with different...
The experiments were conducted on three selected, one-component and colourless
lacquers based on waterborne acrylic binders intended for the surface finishing
of furniture as well as of other wood materials used indoors. Detailed information
about the lacquers employed in the described investigations are presented in table 1.
One important selection criteria of the experimental lacquer products was the content of solids, which ranged from 32 to 38%.
Table 1. Properties of applied lacquers (on the basis of the manufacturers’ data)
Tabela 1. Parametry techniczne wytypowanych do badań wyrobów lakierniczych (na podstawie danych producenta)
Lacquer
Parameters
Parametry
Lakier
A
Binding agents
B
acrylic dispersion
Środki wiążące
dyspersja akrylowa
Solvents
water
Rozcieńczalnik
Content of solids [%]
Zawartość ciał stałych [%]
Density [g/cm3]
Gęstość [g/cm3]
Commercial viscosity at a temp. of 22 ± 1°C [s] *
Lepkość produktu handlowego w temp. 22 ± 1°C [s] *
Working viscosity at a temp. of 21±1°C [s] *
Lepkość produktu nanoszonego w temp. 22 ± 1°C [s] *
C
woda
32
34
38
1.04
1.02
1.05
30
34
47
22
22
22
*Value measured using a Ford’s cup No. 4
*Wartość mierzona za pomocą kubka Forda nr 4
The lacquers selected for investigation were applied onto samples of oak wood
(Quercus sp.) measuring 280×200×16 mm. The moisture content of the finished
wood, determined by the gravimetric method, was approximately 6.5%; while its
density determined stoichiometrically in accordance with PN-77/D-04101 standard amounted to about 680 kg/m3.
The experimental samples were treated with the tested lacquers to the amount
of about 110 g/m2 and their narrow edges were secured by low-emission aluminium foil. The lacquer-treated wood samples were left outdoors for 24 hours
which, according to the manufacturer’s certificate, allowed their drying to the
required level. Then, the samples were placed in a glass testing chamber of a volume of 0.225 m3. The investigations of the volatile organic compound emissions
were performed in typical conditions in accordance with the recommendations
of RAL-UZ 38 standard:
54
–– temperature – 23ºC ± 1 ºC,
–– air relative humidity – 45% ± 1%,
–– air exchange rate – 1 h-1,
–– chamber load with examined material - 1 m2/m3.
Air samples were collected 24 hours after the experimental elements were
placed in the glass chamber. Each time, three parallel samples were collected as
well as air that constituted the “background” of the chamber. 1000 ml of air at
a rate of 50 ml/min was taken for analysis with a FLEC pump from Chematec
company. The air samples were collected on Tenax TA (120mg; 35/60mesh, Alltech, Deerfield, IL).
Before application, tubes were kept at a temperature of 270oC for 60 minutes, with argon flow of 20 ml/min. Adsorbed analytes were released thermally
in a desorber for 5 min. Then the liberated analytes were transferred in a stream
of inert gas flowing at a rate of 20 cm3/min. into a microtrap. At desorption
termination analytes from the microtrap were released thermally for 90 sec. at
a temperature of 250oC and directed to the head of the chromatographic column.
All desorbed analytes were subjected to chromatographic analysis in conditions
given in table 2.
Table 2. Parameters of TD/GC/MS analytical system
Tabela 2. Parametry układu analitycznego TD/GC/MS
Elements of the system
Elementy układu
Gas chromatograph
Chromatograf gazowy
Parameters
Parametry
TRACE GC, Thermo Quest.
Column
RTX – 624 Restek Corporation, 60m x 0,32mm ID;
Df – 1,8 µm: 6% cyanopropylophenyl, 94% dimethylopolysiloxane
Detector
Mass spectrometer (SCAN: 10 – 350)
Kolumna
RTX – 624 Restek Corporation, 60m x 0,32mm ID;
Df – 1,8 µm: 6% cyjanopropylofenyl, 94% dimetylopolisiloksan
Detektor
Spektrometr mas (SCAN: 10 – 350)
Injector
Thermal desorber connected with sorption microtrap;
Rinsing gas: argon 20 m3min-1;
Rinsing time: 5 min.
Microtrap
Sorbent: 80 mg Tenax TA/30 mg Carbosieve III;
Desorption temperature: 250°C during 90 s.
Dozownik
Termiczny desorber połączony z pułapką sorbcyjną;
Gaz płuczący: argon 20 m3min-1;
Czas płukania: 5 min.
Mikropułapka
Sorbent: 80 mg Tenax TA/30 mg Carbosieve III;
Temperatura desorpcji: 250°C przez 90 s.
Carrier gas
Helium: 100 kPa, ~2 cm3min-1.
Gaz nośny
Hel: 100 kPa, ~2 cm3min-1.
55
Table 2. Continued
Temperature setting
Program temperaturowy
40°C during 2 min, 7°C min-1 to 200°C, 10°C min-1 to 230°C,
230°C during 20 min
40°C przez 2min, 7°C min-1 do 200°C, 10°C min-1 do 230°C, 230°C
przez 20 min.
Compound identification: compounds were identified by comparing the mass
spectra obtained with the spectra stored in NIST 98 library and then confirmed by
collating the mass spectra and retention times of the identified compounds with
the spectra and retention times of appropriate standards.
Quantitative analysis: a quantitative analysis of the volatile organic compounds emitted from the examined surfaces was carried out using the method
of addition of 4-bromo-1-fluorobenzene standard.
In order to determine change trends in the emission of volatile compounds in
time, the investigations were carried out in cycles: 24 hours, 14 days, and 28 days
after finishing the wood samples with the tested lacquers.
Measurements of the concentrations of harmful substances present in the air collected from the chamber filled with the examined materials revealed quantitative
and qualitative differences in the volatile organic compounds emitted by those
materials. Fig. 1 presents a comparison of the profiles of the volatile organic compounds emitted from the samples coated with waterborne lacquers.
56
Fig. 1. Chromatograms of separation of volatile organic compounds emitted by oak
wood surfaces coated with: a) lacquer A, b) lacquer B, c) lacquer C, 24 hours after
the treatment
Rys. 1. Chromatogramy rozdziału lotnych związków organicznych emitowanych przez powierzchnie drewna dębowego pokryte: a) lakierem A, b) lakierem B, c) lakierem C, po 24h
od ich uszlachetnienia
The results obtained indicate that, after application onto the surface of oak
wood, the investigated waterborne lacquers primarily emitted compounds from
the group of glycol ethers, and aliphatic and aromatic hydrocarbons. The domi-
57
nant group of compounds released by all the tested products comprised glycol
ethers. Their proportion of the total emission during the first stage of experiments
ranged from 64.5 to 85.3%. In addition, wood surfaces finished with lacquers
A and B also released relatively high quantities of aliphatic hydrocarbons (from
5.5 to 21.5%); while samples coated with lacquer C emitted significant amounts
of aromatic hydrocarbons (15.4%).
Tables 3-5 present detailed results of measurements of volatile organic compounds identified in the air collected from the chamber filled with the tested materials. The results present the mean concentration values of the volatile compounds
from three measurements. The values did not differ from one another by more
than 10%.
Table 3. Volatile organic compounds released from coatings of waterborne lacquer A
applied onto oak wood
Tabela 3. Lotne związki organiczne wydzielane z powłok wodorozcieńczalnego lakieru A naniesionych na drewno dębowe
Compound
Związek
acetic acid
kwas octowy
toluene
toluen
n-nonane
n-nonan
cyclohexane, propyl
propylocykloheksan
ethanol, 2-butoxy
2-butoksyetanol
n-decane
n-dekan
n-undecane
n-undekan
Σ unidentified substances
Σ niezidentyfikowanych substancji
Compound
designation
Oznaczenie
związku
24h
14 days
14 doba
28 days
28 doba
µg/m
3
10.1
6.2
2
5.0
3.9
1.7
3
10.0
4.2
3.8
4
8.2
1.7
1.4
5
1531.0
415.4
137.3
6
60.2
6.9
4.9
7
20.7
1.8
1.0
-
109.1
24.1
22.7
1794
468
179
Total emission of volatile organic compounds
Całkowita emisja lotnych związków organicznych
- Nie stwierdzono
24 hours
49.8
1
- Undetected
Stężenie związków
1
TVOC1:
1
Compound concentration
58
Table 4. Volatile organic compounds released from coatings of waterborne lacquer B
Tabela 4. Lotne związki organiczne wydzielane z powłok wodorozcieńczalnego lakieru B
naniesionych na drewno dębowe
Compound
Związek
acetic acid
kwas octowy
toluene
toluen
n-nonane
n-nonan
cyclohexane, propyl
propylocykloheksan
ethanol, 2-butoxy
2-butoksyetanol
nonane, 3-methyl
3-metylononan
n-decane
n-dekan
nonane, 2,6-dimethyl
2,6-dimetylononan
cyclohexane, butyl
butylocykloheksan
decane, 3-methyl
3-metylodekan
n-undecane
n-undekan
Compound
designation
Oznaczenie
związku
14 days
14 doba
28 days
28 doba
µg/m
3
15.7
9.7
2
4.7
4.4
3.4
3
37.8
10.5
6.2
4
29.1
6.1
4.1
5
1086.9
517.4
251.7
6
12.7
4.3
2.3
8
149.4
31.3
22.1
9
31.7
10.5
6.7
10
26.7
6.4
5.5
11
23.2
14.7
8.6
12
52.1
12.7
4.8
-
158.2
63.0
44.9
1684
697
370
- Nie stwierdzono
24h
71.5
1
- Undetected
24 hours
1
TVOC1:
1
59
Table 5. Volatile organic compounds released from coatings of waterborne lacquer C
Tabela 5. Lotne związki organiczne wydzielane z powłok wodorozcieńczalnego lakieru C
naniesionych na drewno dębowe
Compound
Związek
acetic acid
kwas octowy
toluene
toluene
m-xylene
m-ksylen
o-xylene
o-ksylen
ethanol. 2-butoxy
2-butoksyetanol
benzene. propyl
propylobenzen
1.2.3-trimethylbenzene.
1.2.3-trimetylobenzen
1-ethyl-4-methylbenzene
1-etylo-4-metylobenzen
1.3.5-trimethylbenzene.
1.3.5-trimetylobenzen
1-(2-methoxy-1-methylethoxy)-2-propanol
1-(2-metoksy-1-metyloetoksy)-2-propanol
dipropylene glycol methyl ether
(isomer)
eter metylowy glikolu dipropylenowego (izomer)
1-(2-methoxypropoxy)-2-propanol
1-(2-metoksypropoksy)-2-propanol
Compound
designation
Oznaczenie
związku
14 days
14 doba
28 days
28 doba
µg/m3
5.2
5.1
2
3.8
2.4
1.8
3
5.3
3.1
1.0
4
13.1
7.6
-
5
231.7
46.1
13.9
6
3.9
2.9
2.4
26.4
12.1
-
9
7.3
2.9
-
10
19.7
12.8
11.9
11
19.6
14.9
13.9
12
20.4
18.6
17.6
-
24.1
17.4
16.9
388
146
85
7
8
- Nie stwierdzono
24h
12.7
1
- Undetected
24 hours
1
TVOC1:
1
60
The main constituent released by all examined materials was 2-butoxyethanol. The concentration of that compound ranged from 231.7 to 1531.0 µg/m3.
Among the tested lacquers, the lacquer coatings containing the highest amounts of
solids (38%, lacquer C) emitted the smallest quantities of 2-butoxyethanol; while
the highest quantities of that compound were released by surfaces finished with
lacquer A, which contained the smallest amounts of solids (32%).
The surfaces finished with lacquer C also emitted other compounds belonging
to glycol ethers, e.g. 1-(2-methoxy-1-methylethoxy)-2-propanol, methyl ether of
dipropylene glycol, as well as 1-(2-methoxypropoxy)-2-propanol. Characteristic
components of emissions from coatings of A and B lacquers also included compounds belonging to aliphatic hydrocarbons. Coatings of lacquer A released primarily: n-nonane, n-decane, n-undecane; whereas coatings of lacquer B also emitted
propylcyclohexane, butylcyclohexane, 3-methylnonane, 2,6-dimethylnonane or
3-methyldecane. On the other hand, surfaces finished with lacquer C released aromatic hydrocarbons of which the most interesting were emissions of m-,o-xylene
as well as 1,2,3-trimethylbenzene and 1,3,5-trimethylbenzene.
All examined samples also emitted acetic acid to the amount of 12.7-71.5 µg/m3.
The source of acetic acid emissions was oak wood, which was confirmed by experiments carried out on untreated oak wood samples as well as investigations conducted by Risholm-Sundman et al. [1998].
The total concentrations of all volatile organic compounds released by examined surfaces 24 hours after the treatment are presented in fig. 2. The overall quantity of compounds emitted by coatings of waterborne lacquers ranged from 388
to 1794 µg/m3. The greatest quantities of volatile organic compounds were released
by coatings of lacquer A, which contained the lowest amounts of solids. In the first
stage of the experiments, the amount of compounds liberated from coatings developed from lacquer A was over 4.5 fold higher than that determined for coatings
formed by lacquer C, characterised by the highest content of solids. On the other
hand, the total quantity of all volatile compounds released by surfaces finished with
A and B lacquers 24 hours after the treatment differed only slightly. However, the
profile of compounds released into the atmosphere was significantly more diverse.
During the first 14 days the emission levels of all identified compounds decreased significantly. For example, in the case of surfaces finished with lacquer A, concentrations of 2-butoxyethanol, which constituted the main compound
released by waterborne coatings, decreased by approximately 73%, in the case
of lacquer B by about 52% and in the case of lacquer C by about 80%.
The quantity of all compounds (TVOC) emitted by waterborne coatings
in the course of 14 days decreased by about 59 to 74%. Fourteen days after the
treatment, experimental materials released volatile organic compounds at the
level of 146-697 µg/m3. The greatest drop of emissions was recorded for product
A characterised by the highest emissions in 24 hours after lacquer application;
while the lowest was observed in the case of product B.
61
Fig. 2. Comparison of TVOC released by coatings of waterborne lacquers 24 hours
after their application onto the surface of oak wood
Rys. 2. Porównanie TVOC wydzielanych przez powłoki wodorozcieńczalne po 24h od naniesienia ich na powierzchnię drewna dębu
In the course of the following 14 days, quantities of volatile organic compounds released by coatings of waterborne lacquers decreased further, ranging from
85- 370 µg/m3. The lowest emissions of volatile organic compounds 28 days after
the treatment were determined in the case of product C and the highest for product
B, similar to the results recorded 14 days after application of tested lacquers.
To summarise, it can be said that the quantities of volatile organic compounds
released by the examined coatings of waterborne lacquers during the first 28 days
after their application onto oak wood surfaces decreased by 78 to 90%.
The quantitative changes of VOC released by the coatings of waterborne lacquers during the first 28 days after their application onto oak wood are given
in fig. 3.
Fig. 3. Change of volatile organic compounds concentrations in time for examined
coatings applied onto oak wood
Rys. 3. Zmiany stężenia lotnych związków organicznych w czasie, wydzielanych przez badane powłoki naniesione na drewno dębu
62
Conclusions
The conducted research confirmed the need for qualitative and quantitative characterisation of harmful substances emitted by surfaces finished with acrylic
waterborne lacquers. Moreover, it also confirmed the fact that emission levels
of volatile organic compounds released from these products may change in a wide
range of values. In the case of the two tested products (lacquer A and B), the total
content of all volatile organic compounds released into the air collected from the
chamber was relatively high and, 24 hours after their application onto the surface of oak wood, fluctuated from 1794 to 1684 µg/m3. Much lower emissions
of volatile organic compounds were determined in the case of coatings of lacquer
C (388 µg/m3) characterised by the highest content of solids of all tested products.
The highest quantities of compounds released by examined lacquers belonged
to glycol ethers. The principal constituent of those emissions was 2-butoxyethanol, which constituted from 59.7 to 81.1% of all released compounds. In addition,
those emissions also contained small quantities of aliphatic and aromatic hydrocarbons. It is worth mentioning that aliphatic hydrocarbons were characteristic
constituents of emissions from coatings developed from A and B lacquers; whereas aromatic hydrocarbons were released in significant amounts from coatings
formed by lacquer C.
Acknowledgements
The research was carried out within Project No. N N309 165839 funded by the National
Science Centre in Poland.
References
Asendof H. [1996]: Lakiery w przemyśle meblarskim. W: Nowe technologie, obrabiarki, urządzenia, materiały i akcesoria dla meblarstwa. Zakopane: 135-139
Dziewanowska-Pudliszak A. [2007]: Emisja lotnych związków organicznych z powłok lakierowych naniesionych na lite drewno. W: Technologia drewna – wczoraj, dziś, jutro. Studia
i szkice na Jubileusz Profesora Ryszarda Babickiego. Wyd. ITD, Poznań: 295-306
Kuczyńska H. [2005]: Wodorozcieńczalne wyroby lakierowe - skład i porównanie z lakierami
konwencjonalnymi. Lakiernik 3: 13-18
Lurka J. [2007]: Jak nakładać wodorozcieńczalne? Meblarstwo 4 [76]: 64-65
Proszyk S. [2007]: Postęp w dziedzinie wyrobów lakierowych i technologii ich stosowania
w drzewnictwie. W: Technologia drewna – wczoraj, dziś, jutro. Studia i szkice na Jubileusz Profesora Ryszarda Babickiego. Wyd. ITD, Poznań: 115-124
RAL-UZ 38 [2002]: Basic Criteria for Award of the Environmental Label. Low-Emission
Wood Products and Wood-Base Products
Risholm- Sundman M., Lundgren M., Vestin E., Herder P. [1998]: Emissions of acetic acid
and other volatile organic compounds from different species of solid wood. Holz als Roh-und Werkstoff 56 [2]: 125-129
63
Salthammer T. [1997]: Emission of Volatile Organic Compounds from furniture Coatings.
Indoor Air 7: 189-197
Scheithauer M., Aehlig K. [1995]: Flüchtige organische Bestandteile (VOC) und Geruch
lackierter Oberflächen – ein Kriterium für die Umweltfreundlichkeit moderner Möbel.
W: Wymagania Unii Europejskiej a stan higieniczności mebli i materiałów stosowanych
do ich produkcji. Poznań-Kiekrz. Wyd. ITD., Poznań: 29-44
EMISJA LOTNYCH ZWIĄZKÓW ORGANICZNYCH (VOC)
Z WODOROZCIEŃCZALNYCH WYROBÓW LAKIEROWYCH
O ZRÓŻNICOWANEJ ZAWARTOŚCI CIAŁ STAŁYCH
Streszczenie
Przedstawiono wyniki badań emisji lotnych związków organicznych z powierzchni drewna dębowego, uszlachetnionego akrylowymi lakierami wodorozcieńczalnymi. Użyte wyroby lakierowe charakteryzowały się różną zawartością ciał stałych, która zmieniała się
w zakresie od 32 do 38%. Lotne związki organiczne analizowano techniką chromatografii
gazowej połączonej ze spektrometrią mas i termiczną desorpcją (GC/MS/TD). Jako medium adsorpcyjne zastosowano Tenax TA. Uzyskane rezultaty wskazują, iż emisja lotnych związków organicznych z wyrobów wodorozcieńczalnych zmieniała się w szerokim
zakresie, od 388 do 1794 µg/m3. Głównymi składnikami emisji były związki należące
w większości do eteroglikoli, węglowodorów alifatycznych oraz aromatycznych.
Słowa kluczowe: lakiery wodorozcieńczalne, lotne związki organiczne (VOC), chromatografia
gazowa, spektrometria mas, termiczna desorpcja
DONIESIENIA NAUKOWE - RESEARCH REPORTS
Mária Krajčovičová1
Determination of bottlenecks in the production of wooden
constructions
Every production process has issues to deal with. One of these problems is the
issue of bottlenecks. It is possible to reveal them through the use of optimising
models that are inseparable parts of every production process these days. This
article discusses the revelation of these problems during the production process.
As an example we have used the production of wooden constructions. It is possible
to use mathematical models, which were produced and applied in MATHEMATICS
5 program, for the revelation of bottlenecks as well as for subsequent production
planning with a view to avoiding their formation.
Keywords: manipulation with material, optimisation, wooden constructions, bottlenecks, mathematical methods
Introduction
For production control it is important to know how to design the most optimal solutions which are not money-consuming and at the same time make it possible to
yield the highest possible profit. To ignore quality would mean to lose customers.
Therefore quality should be a main priority. In order to make profit and maintain
a high quality of products, it is necessary to design the production process with
the lowest risks possible, both technically and technologically. To achieve this
goal, it is possible to use a program that re-evaluates the already existing process
and identifies its bottlenecks, thus allowing us to find possible solutions to the
problems pointed out. The most suitable programs for that purpose are simulative
optimisation programs.
Mária Krajčovičová, Technical Univeristy, Zvolen, Slovakia
66
Mária Krajčovičová
The solution to the problem of production process optimisation
A subsequent methodical order was designed to solve the issue of production process optimisation:
–– analysis and appellation of basic optimisation conditions (technological, economical, time, qualitative and quantitative),
–– the influence of each criterion on the progress of the optimisation process of
material flow,
–– mathematical model of optimisation,
–– selection and evaluation of the most suitable solution.
In the first place it was necessary to define what was essential in order to optimise the process. The second step was to decide how to do it. We asked ourselves
these questions and acted in accordance with the answers we arrived at.
First of all, from summary tables for the production of the desired number
of constructions we created a matrix for the determination of the minimal machine load (the lowest possible number of machines used). We developed a work
plan for each machine to find out what were the options of production of each
component by number of machines defined by us. We based our work on a matrix
that defined the components, machines and time of each machine needed for the
production of construction components (we used different marking which we selected by defining linear programming).
Note: the mark Cm,n means that matrix C has m-rows and n-columns.
Subsequently we created matrix B that described the number of components
in every type of construction, as well as the price of constructions and the production time of one construction.
The solution for the production of wooden constructions
GRINGO – IMAGO – PEDRO
Analysis of the production process of GIP constructions
(GRINGO – IMAGO – PEDRO)
For analysis of the production process it was necessary to focus on the time data
of production machines for each construction, which meant designing a matrix of
each machine time required for production of constructions.
We knew/designed matrix C (table 1), which we also called the matrix of time
consumed by each machine for the production of components. Columns from H1
to H31 present individual components and rows from S1 to S9 present machines;
while the fields in the matrix are filled with values of production times of machine
by each component. Matrix B (Tab.2) is a matrix of consumption of each component which includes the quantity of pieces of each component from H1 to H31 in
each type of construction from D1 to D11 required to build a given construction.
67
Determination of bottlenecks in the production of wooden constructions
(1)
C9,31= (cik), cik
- the consumption of time of i-machine for the production of k-component
Table 1. Matrix C
Tabela 1. Macierz C
H1 H2 H3 H4 H5 H6 H7 H8 H9 H10 H11 H12 H13 H14 H15 H16 H17 H18 H19 H20 H21 H22 H23 H24 H25 H26 H27 H28 H29 H30 H31
bi
S1 140 140 140 140 140 140 140 140 140 140 200 140 140 140 140 140 140 140 140 140 140 140 140 140 140 140 200 200 140 140 140 28800
S2 605 605 605 605 605 605 618 618 1226 618 613 605 605 605 605 605 615 605 615 605 605 605 605 605 605 605 613 613 613 605 605 28800
S3 240 240 240 290 290 290 180 180 155 180 0 340 440 415 340 155 155 230 205 280 330 530 180 205 230 505 0
0 180 0
0 28800
S4 188 188 188 280 290 290 154 154 0 154 154 178 178 154 142 0 142 0
0
0
0
0
0
0
0
0 154 0 142 192 192 28800
S5
0
0
0
0
0
0
0
0 133 0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0 28800
S6
0
0
0
0
0
0
0
0 720 0
0
0
0
0
0 840 0
0
0
0
0
0
0
0
0
0
0
0 720 0
0 28800
S7
0
0
0
0
0
0
0
0
0 720 720 0
0
0
0
0
0
0
0
0
0
0
0
0
0
0 720 720 0
S8
0
0
0
0
0
0
0
0
0
0
0
0
0
0 145 145 145 145 145 145 145 145 145 0
0
0
0
0
0
0
0
0
0 28800
0
0 28800
S9 36 36s 36s 36s 36s 36s 36s 36s 36s 36s 36s 36s 36s 36s 36s 36s 36s 36s 36s 36s 36s 36s 36s 36s 36s 36s 36s 36s 36s 36s 36s 28800
B31,11= (bkj), bkj
(2)
- the consumption of k-component for j-construction
Table 2. Matrix B
Tabela 2. Macierz B
D1
D2
D3
D4
D5
D6
D7
D8
D9
D10
D11
H1
0
3
4
12
18
24
0
0
0
0
0
H2
1
1
4
12
18
24
0
0
0
0
0
H3
0
1
4
12
16
24
0
0
0
0
0
H4
0
0
1
8
12
16
0
0
0
0
0
H5
1
2
2
12
18
24
0
0
0
0
0
H6
0
0
3
12
18
24
0
0
0
0
0
H7
1
4
4
12
16
24
0
0
0
0
0
H8
0
2
4
12
16
24
0
0
0
0
0
H9
1
2
4
12
16
24
0
0
0
0
0
H10
4
4
4
12
20
24
0
0
0
0
0
H11
2
2
2
4
12
8
0
0
0
0
0
H12
0
0
0
0
0
0
1
6
0
0
0
H13
0
0
0
0
0
0
1
7
0
0
0
H14
0
0
0
0
0
0
2
4
0
0
0
H15
0
0
0
0
0
0
1
4
0
0
0
H16
0
0
0
0
0
0
3
6
0
0
0
H17
0
0
0
0
0
0
4
8
0
0
0
H18
0
0
0
0
0
0
2
4
0
0
0
H19
0
0
0
0
0
0
0
4
0
0
0
H20
0
0
0
0
0
0
2
4
0
0
0
H21
0
0
0
0
0
0
0
4
0
0
0
H22
0
0
0
0
0
0
0
6
0
0
0
H23
0
0
0
0
0
0
4
6
0
0
0
H24
0
0
0
0
0
0
1
4
0
0
0
H25
0
0
0
0
0
0
0
2
0
0
0
H26
0
0
0
0
0
0
0
1
0
0
0
H27
0
0
0
0
0
0
2
4
0
0
0
H28
0
0
0
0
0
0
20
50
0
0
0
H29
0
0
0
0
0
0
0
1
0
0
0
H30
0
0
0
0
0
0
0
0
0
0
168
H31
0
0
0
0
0
0
0
0
2
4
12
68
A matrix of time consumed by each machine to complete constructions was
named A9,11= (aij), where aij is time consumption of i-machine for completion of
j-construction. From the above, it follows that it was necessary to find the components that defined matrix A (Tab. 3).
In the following step we searched for components aij.
aij = ci1.b1j + ci2.b2j +.............+ ci31.b31j , so
(3)
A9,11 = C9,31× B31,11
Table 3. Matrix A
Tabela 3. Macierz A
D1
D2
D3
D4
D5
D6
D7
D8
D9
D10
D11
S1
1520
3060
5160
17040
25920
34080
7340
20740
6160
12320
25200
S2
6750
14093
24436
80552
119608
161104
26231
76185
26620
53240
108900
S3
1585
3890
7400
26260
38240
52520
4980
20715
0
0
0
S4
1556
3368
6142
22128
33432
44256
1682
5392
8448
16896
34560
S5
133
266
532
1596
2128
3192
0
0
0
0
0
S6
720
1440
2880
8640
11520
17280
2520
5760
0
0
0
S7
4320
4320
4320
11520
23040
23040
15840
38880
0
0
0
S8
0
0
0
0
0
0
1305
5075
0
0
0
S9
360
756
1296
4320
6480
8640
1548
4500
1584
3168
6840
Subsequently the mathematical model for analysis of the production process
of constructions looked as follows [Fellnerová, Zimka 2000]:
max z (x) = m.x
(4)
A.x ≤ b,
(5)
at the conditions
xj ≥ 0
where input data was:
m – vector of construction prices,
b – vector of dispositional times for each machine,
A – the matrix of time consumption of machines for construction completion.
The output was: x – vector of the production program
xj – number of Dj.
The following programs were used for analysis: PRVYRGIP and VGIPOB.
1. Linear Programming PRVYRGIP (fig. 1) (this program optimises the production process; while its output is the number of constructions produced per
month and the profit that can be made from sale of those constructions).
In this program the input data is:
[{- m}A,{b,-1}{l1,l2,.....ln}]
where lj ≤ xj.
(6)
69
This optimisation program is used if there are no conditions set for constructions or if the user wants to have one construction made in a definite number
of pieces and there are no conditions set for other constructions.
2. Linear Programming VGIPOB (fig. 2) (this program optimises the production
process by restricting some of construction types).
In this program the input data is:
[{- m}A,{b,-1}{{l1,u1}, {l2,u2}......{ ln, un}}]
(7)
where lj ≤ xj≤ uj.
It is possible to use this program in the case when one type of construction
has been cumulating in the warehouse, so the company does not need to produce
it for some time. In this program the user defines the construction that is stored in
the warehouse and the program recommends which constructions and at what cost
should be produced. Also in this case the price and the number of each construction recommended by the production optimisation program are the input data.
In the first case the whole production program is changed ; ,while in the
second the production of some types of constructions is restricted and the production of other types is increased.
The results of the first program, i.e. PRVYRGIP, are presented in the following picture, showing the main position of the program that is the basis for optimisation as well as the most optimal solution:
Fig. 1. Production program PRVYRGIP
Rys. 1. Program produkcji PRVYRGIP
70
Key (Legenda):
1 ‒ The matrix of time consumed by machines for completion of constructions,
Macierz czasu zużywanego przez maszyny na ukończenie konstrukcji,
2 ‒ Linear programming,
Programowanie liniowe,
3 ‒ Vector of construction prices,
Wektor cen konstrukcji,
4 ‒ Vector of dispositional times of each machine,
Wektor czasów dyspozycyjnych każdej maszyny,
5 ‒ Vector of restricting conditions of the production program,
Wektor warunków ograniczających program produkcji,
6 ‒ Matrix P,
Macierz P,
7 ‒ Vector of the optimal production program,
Wektor optymalnego prorgamu produkcji,
8 ‒ Profit per month,
Miesięczny zysk.
The results of the second program, i.e. VGIPOB, are presented in the following picture which depicts the main position of the program that is the basis for
optimisation and also the most optimal solution:
Fig. 2. Production program VGIPOB
Rys. 2. Program produkcji VGIPOB
Key (Legenda):
1 ‒ The matrix of time consumed by machines for completion of constructions,
Macierz czasu zużywanego przez maszyny na ukończenie konstrukcji,
71
2 ‒ Linear programming,
Programowanie liniowe,
3 ‒ Vector of construction prices,
Wektor cen konstrukcji,
4 ‒ Vector of dispositional times of each machine,
Wektor czasów dyspozycyjnych każdej maszyny,
5 ‒ Vector of restricting conditions of the production program,
Wektor warunków ograniczających program produkcji,
6 ‒ Matrix P,
Macierz P,
7 ‒ Vector of the optimal production program,
Wektor optymalnego prorgamu produkcji,
8 ‒ Profit per month,
Miesięczny zysk.
Should the chosen production program be impossible to implement, the program returns a mistake in the linear programming.
In the end we can see that the production program has a bearing not only on
the profit from product sale, but also on the composition and consumption of the
production resources. As previously mentioned, in the case considered here, the
program also affected the time disposal of each machine.
In order to examine the fatigability of each machine, time limits we added to
PRVYRGIP program the command: Q = A.Out[v], where v means the number
of output from the computer which determines a relevant production optimisation
program (fig. 3).
The following results were achieved for the most optimal production program:
Fig. 3 Production program 1
Rys. 3 Program produkcji 1
72
Key (Legenda):
1 ‒ Command added: Q = A.Out[v],
Polecenie dodane: Q = A.Out[v],
2 ‒ Out[v] (in this case 11),
Out[v] (w tym przypadku 11).
Conclusions
The mathematical optimisation programs created confirmed that it is possible
to reveal bottlenecks by planning, as well as to avoid them. Constructions and
their production were good examples of model situations of production planning.
MATHEMATICS 5 program proved to have been a good tool, thanks to which
it was possible to use mathematical optimisation programs. The programs of linear programming, i.e. PRVYRGIP and VGIPOB, helped us reveal bottlenecks
and plan production in a way to avoid them. Therefore, while designing material
flows, all technologists, not only those from the wood processing industry, should
base their designs on mathematical models. Already in the stage of idea creation
it is necessary to think about the production process and potential difficulties.
Product quality is created already in the design stage and refined in production.
It is very important to create mathematical models of such difficult systems,
so as to be able to optimise the production process in the best way possible and at
the same time maintain the highest quality possible and set the lowest price. The
mathematical model we created and used, is suitable not only for the production
of toys or constructions, but also for the any type of production in the wood processing industry, provided that more than one product is manufactured.
References
Krajčovičová M. [2010]: Optimalizácia materiálového toku pri výrobe drevených stavebníc,
PhD thesis
Fellnerová P., Zimka R. [2000]: Lineárne programovanie v ekonómii. Banská Bystrica
OKREŚLENIE WĄSKICH GARDEŁ W PRODUKCJI
KONSTRUKCJI DREWNIANYCH
Streszczenie
W każdym procesie produkcyjnym pojawiają się problemy, z którymi trzeba sobie poradzić. Jednym z tych problemów jest zagadnienie wąskich gardeł. Ich identyfikacja
73
jest możliwa dzięki wykorzystaniu modeli optymalizacyjnych, będących obecnie
nieodłącznymi elementami każdego procesu produkcyjnego. W niniejszym artykule
omówiono identyfikację tych problemów już w trakcie procesu produkcyjnego. Za
przykład posłużyła produkcja konstrukcji drewnianych. W celu identyfikacji wąskich
gardeł, jak również planowania produkcji, w taki sposób aby ich uniknąć, możliwe
jest wykorzystanie modeli matematycznych, które autorzy opracowali i zastosowali
w środowisku programu MATHEMATICS 5.
Słowa kluczowe: manipulacja materiałem, optymalizacja, konstrukcje drewniane, wąskie gardła,
metody matematyczne
KOMUNIKATY – ANNOUNCEMENTS
Weronika Przybylska, Jadwiga Zabielska - Matejuk1
ŚWIATOWY KONGRES NA TEMAT CIECZY JONOWYCH
COIL-4
W czerwcu 2011roku w USA odbył się ��
Światowy��
Kongres na temat Cieczy Jonowych, w którym udział wzięło ponad 450 uczestników z całego świata. Celem Kongresu było przedstawienie najnowszych wyników badań naukowych prowadzonych
w zakresie cieczy jonowych oraz możliwości ich zastosowania w przemyśle.
Słowa kluczowe: ciecze jonowe, biomasa, ochrona drewna, synteza
W dniach 15–18 czerwca 2011 roku w Waszyngtonie odbył się Międzynarodowy Kongres na temat Cieczy Jonowych (COIL), zorganizowany przez American
Chemical Society. Kongres ten był czwartym z kolei spotkaniem najwyższej klasy
naukowców zajmujących się cieczami jonowymi. Wcześniejsze spotkania odbyły
się w Salzburgu (Austria, COIL-1; 2005), Yokohamie (Japonia, COIL-2; 2007)
oraz w Cairns (Australia COIL-3; 2009). W tegorocznym Kongresie uczestniczyło ponad 450 uczestników z całego świata, w tym z USA, Australii, Chin, Korei,
Indii, Portugalii, Irlandii Północnej, Niemiec, Danii, Wielkiej Brytanii, Hiszpanii,
Francji, Austrii i Polski. Program naukowy Kongresu, uwzględniając wieloaspektowość działania szerokiej gamy nowatorskich związków organicznych jakimi są
ciecze jonowe, obejmował takie obszary badawcze jak: chemia, separacja, kataliza i biotechnologia, materiały, energia odnawialna, biomasa, paliwa ze źródeł
odnawialnych, farmaceutyki, biocydy.
Celem Kongresu było przedstawienie najnowszych wyników badań naukowych prowadzonych w zakresie cieczy jonowych oraz możliwości ich zastosowania w wielu gałęziach przemysłu. Obradom przewodniczył Robin D. Rogers,
Weronika Przybylska, Instytut Technologii Drewna, Poznań, Polska
Jadwiga Zabielska - Matejuk, Instytut Technologii Drewna, Poznań, Polska
76
Weronika Przybylska, Jadwiga Zabielska - Matejuk
światowej sławy naukowiec w dziedzinie syntezy i badań nad cieczami jonowymi
z Uniwersytetu w Alabamie. Program konferencji składał się z ośmiu wykładów
plenarnych, 90 referatów oraz licznych dyskusji. Sesje posterowe, w trakcie których zaprezentowano ponad 180 posterów, umożliwiły naukowcom i inżynierom
z całego świata wymianę doświadczeń i stanu wiedzy na temat cieczy jonowych
i ich aplikacji. Tematami wiodącymi w wygłaszanych referatach były: właściwości cieczy jonowych, struktury, interakcje i aplikacje cieczy jonowych, ich zastosowanie w „zielonych” technologiach, elektrochemia oraz wykorzystanie cieczy
jonowych w przetwarzaniu biomasy.
Nie jest łatwo omówić szeroką tematykę bardzo wartościowych prac przedstawianych na Kongresie, aby nie pominąć tych najważniejszych dla rozwoju nauki o cieczach jonowych oraz możliwości ich efektywnego wykorzystania. Codzienne, przedpołudniowe wykłady plenarne wygłaszane przez światowej sławy
profesorów: K.R. Seddona, P.C. Trulove, M.B. O’Meara, D.W. Armstronga, Y.
Koo, L.P.N. Rebelo, J. F. Brenecce, D.R. MacFarlane, oraz C.A. Angell stanowiły
wartościowy wstęp do dalszej części obrad, czyli sesji tematycznych, w skład
których wchodziło 90 referatów. Paul C. Trulove z Akademii Marynarki Wojennej
Stanów Zjednoczonych w Annapolis przedstawił w ramach wykładu plenarnego
nie tylko ciecze jonowe jako rozpuszczalniki biopolimerów, ale też udowodnił,
że przez regulację parametrów procesu rozpuszczania w sposób kontrolowany
można reorganizować sieć wiązań wodorowych w naturalnych biopolimerach.
Zauważono intensyfikację poszukiwania nowych struktur i badań cieczy jonowych w kontakcie z naturalnymi polimerami celulozowymi i lignocelulozowymi.
Wielu znanych specjalistów prezentowało swoje wyniki badań nad cieczami
jonowymi wykorzystywanymi w przetwarzaniu biomasy. Na szczególne zainteresowanie zasługują referaty: Katheriny Bica z Austrii oraz Ikenna Anugwoma z Finlandii, którzy przedstawili problematykę i wyniki badań rozpuszczania
i frakcjonowania drewna za pomocą cieczy jonowych.Wśród szerokiej grupy
uczestników kongresu znaleźli się również przedstawiciele Instytutu Technologii
Drewna w Poznaniu: Jadwiga Zabielska – Matejuk i Weronika Przybylska oraz
Andrzej Skrzypczak z Uniwersytetu Technologicznego w Poznaniu, którzy podczas konferencji przedstawili wyniki swoich badań nad syntezą i zastosowaniem
pojedynczych i podwójnych cieczy jonowych z kationem amoniowym jako skutecznych środków ochrony drewna, jak również ich oddziaływaniem na drewno
i glebę. Opracowanie nowych fungicydów na bazie cieczy jonowych do ochrony
materiałów lignocelulozowych budziło zainteresowanie uczestników Kongresu.
Wymienione prace badawcze realizowane są w ramach projektu rozwojowego
nr POIG.01.03.01-30-074/08 oraz własnego nr NN 309070636 finansowanych
ze środków Unii Europejskiej oraz MNiSzW. Wykorzystanie cieczy jonowych
do rozpuszczania celulozy, a także rozdziału surowców lignocelulozowych
w celu wyodrębnienia ich podstawowych składników chemicznych, prezentowane
w licznych wystąpieniach kongresowych, pozwoliło potwierdzić słuszność i ak-
Światowy kongres na temat cieczy jonowych coil-4
77
tualność podjętych w projekcie rozwojowym celów badawczych i zweryfikować
uzyskane w tym zakresie wyniki własne.
Liczne dyskusje prowadzone po referatach i w trakcie sesji posterowych oraz
w kuluarach potwierdzają, że czwarty Kongres na temat Cieczy Jonowych stanowił ważne forum wymiany doświadczeń pomiędzy przedstawicielami różnych
dyscyplin badawczych oraz osób związanych z przemysłem stosującym ciecze
jonowe. Następny światowy kongres o cieczach jonowych COIL-5 odbędzie się
w Portugalii w 2013 roku, umożliwiając po raz kolejny specjalistom z całego
świata przedstawienie najnowszych wyników badań z dziedziny cieczy jonowych.
THE 4th CONGRESS ON IONIC LIQUIDS
Summary
The 4th Congress on Ionic Liquids was held in Washington DC in USA in June 2011. The
conference was attended by over 450 participants from around the world. The aim of the
Congress was to present the latest achievements in the field of ionic liquids and possibilities of their use in industry.
Keywords: ionic liquids, biomass, wood protection, synthesis
Kazimierz A. Orłowski1
20. MIĘDZYNARODOWE SEMINARIUM MECHANICZNEJ
OBRÓBKI DREWNA W SZWECJI
W czerwcu 2011 roku w Szwecji odbyło się kolejne seminarium z zakresu obróbki drewna, na którym prezentowane były osiągnięcia w dziedzinie narzędzi skrawających do obróbki drewna, procesów obróbkowych i urządzeń. Liczne referaty,
przedstawiane przez specjalistów wiodących ośrodków naukowych i przemysłu na
sesjach plenarnych i plakatowych obejmowały prace typowo teoretyczne, eksperymentalne oraz opracowania o charakterze utylitarnym.
Słowa kluczowe: obróbka mechaniczna drewna, seminarium, konferencja
W pierwszych dniach czerwca 2011 roku odbyło się w Skellefteå w Szwecji
20th International Wood Machining Seminar (20. Międzynarodowe Seminarium
Obróbki Drewna), zorganizowane przez Wood Technology Division Luleå University of Technology (Wydział Technologii Drewna z siedzibą w Skellefteå, Uniwersytetu Technologicznego w Luleå). Oprócz Luleå University of Technology
patronat nad seminarium miało również IUFRO (the International Union of Forest Research Organizations). Seminarium z tego cyklu po raz pierwszy odbyło się
w San Francisco (USA) w 1963 roku. Od tego czasu stanowi forum międzynarodowych spotkań naukowców i specjalistów z przemysłu, podczas których prezentowane są najnowsze osiągnięcia w dziedzinie narzędzi skrawających do obróbki
drewna, procesów obróbkowych i urządzeń. Kolejnym bardzo ważnym celem
tych spotkań jest dynamizowanie wymiany informacji praktycznych pomiędzy
specjalistami z zakresu obróbki drewna. Niekiedy podczas dyskusji dotyczących
prezentacji można było niestety usłyszeć: „Przepraszam, nie jestem upoważniony
do ujawniania szczegółów!” (bardzo częsta odpowiedź prelegentów z przemysłu). Oprócz tego, w ramach zwiedzania zakładów przemysłowych było możliwe
poznanie ich aktualnego stanu techniki, zarówno podczas seminarium, a także
w czasie wycieczki, która w tym roku odbywała się nietypowo, przed konferencją. W niniejszym sprawozdaniu zostanie jedynie przedstawiona relacja z samego
Kazimierz A. Orłowski, Politechnika Gdańska, CNR-IVALSA (National Research
Council of Italy – Timber and Trees Institute)
80
Kazimierz A. Orłowski
seminarium. Dla wielu uczestników, dodatkową atrakcją były trwające na dalekiej
północy Szwecji tzw. białe noce.
W 20. IWMS uczestniczyło ponad stu uczestników, reprezentujących większość kontynentów. Tegoroczne spotkanie gościło wielu przedstawicieli firm obrabiarkowych i narzędziowych, m. in.: ASPI i GASSTECH z Polski, Kanefusa
Corporation (Japonia), Leuco (Niemcy), AB Sandvik Hard Materials (Szwecja),
Söderhamn Eriksson (Szwecja), Super Thin Saws (USA) i Micor (Szwecja). Polskie środowisko naukowe było reprezentowane tradycyjnie przez Politechnikę
Gdańską (1 uczestnik) i przez SGGW w Warszawie (2 uczestników).
Obrady 20. IWMS rozpoczęły się w dniu 8. czerwca od uroczystego otwarcia przez Andresa Grönluda z LUT, przewodniczącego Komitetu Organizacyjnego, a po nim, słowo wstępne wygłosił Gary Schajer z University of British
Columbia (Vancouver, Kanada), przewodniczący Międzynarodowego Komitetu
Doradczego IWMS. Prof. Schajer wspomniał kilku kolegów, którzy w ostatnich
latach odeszli, a byli ważni dla środowiska naukowców związanych z obróbką
drewna. Wśród nich wymienieni byli: Norman Franz ( –2007, zajmujący się podstawami skrawania drewna i będący jednocześnie pionierem zastosowania strumienia wody do przecinania drewna, tzw. water-jet cutting), William McKenzie
( –2008, specjalista w obszarze skrawania drewna), a także Leonard Valadez
( – 2008, uznany specjalista w zakresie przecinania drewna piłami swobodnie
przemieszczającymi się na wrzecionie, a prowadzonymi jednocześnie w prowadnicach piły. To ostanie rozwiązanie jest bardzo popularne w pilarkach stosowanych w przemyśle w Kanadzie i USA). Zdaniem autora, pośród wymienionych
osób zabrakło Yurija Stakhieva z Rosji (CNIMOD, Archangielsk), wybitnego
eksperta w obszarze dynamiki pił tarczowych, propagatora celowości informowania użytkowników narzędzi o prędkościach krytycznych pił tarczowych, wielokrotnego uczestnika tych seminariów, któremu było poświęcone 17. IWMS
w Rosenheim w Niemczech (2005).
Na tegorocznym seminarium referat przewodni (tzw. key-note) pt. „Future
processing wood raw material” (Przyszłość przerobu surowca drzewnego) wygłosił Arto Usenius (VTT, Finlandia). Całe wystąpienie było skoncentrowane na
uzyskaniu jak największej wydajności materiałowej z dysponowanego przez tartak surowca. We współczesnym (bądź przyszłym) przerobie drewna, przepływ
surowca powinien być „inteligentny”, począwszy już od jego pozyskania w lesie.
To oznacza, że powinno się zastosować nowe podejście typu MRI (Marking –
Reading – Information), w którym zawarte byłyby informacje o jakości surowca,
źródle jego pochodzenia, a także właściwościach wytrzymałościowych materiału
drzewnego, mogące wspomagać współdziałanie pomiędzy producentem a zorientowanym na produkt odbiorcą. Znaczący wpływ na wydajność materiałową ma
na samym początku stosowany system podziału dłużyc na kłody, który powinien
uwzględniać głównie jakość surowca. Ta, niestety, może być dokładnie poznana
nie tylko na podstawie oględzin zewnętrznych (ocena wizualna), lecz głównie
20. Międzynarodowe seminarium mechanicznej obróbki drewna w Szwecji
81
na podstawie wyników skanowania surowca (precyzyjne wykrywanie sęków zewnętrznych i wewnętrznych). Ponadto, powinno dążyć się do dokładnego pomiaru
średnic kłód. Kolejnym etapem przerobu surowca jest umiejętne jego przetarcie.
Prof. Usenius ograniczył się do porównania trzech typowych sposobów przetarcia. Według niego, przetarcie profilowe (profiling), które jest bardzo zbliżone do
przetarcia typu cant sawing, daje dochód przy przerobie kłód z drewna iglastego
o mniejszej średnicy równej ø 250 mm wynoszący w obydwu przypadkach około
130 €/m3. W tych sposobach przetarcia sprzęgi są ustawione na stałe w określonym przedziale czasowym. Z kolei, przy „live sawing” (przecieranie „żywe” – aktywne) sprzęgi są dopasowywane do aktualnych potrzeb, co w efekcie pozwala,
przy tej samej średnicy cieńszego końca kłody, jak w przypadku poprzednim,
nieznacznie zwiększyć dochód do około 150 €/m3. Najlepsze efekty są możliwe
do uzyskania, jeśli po tzw. „live sawing” deski boczne są podawane do pilarek
krawędziowych (wyrównywanie krawędzi), następnie poddawane skanowaniu,
a potem przecinaniu poprzecznemu w celu uzyskania elementów o pożądanej długości. Taki system, zwany tutaj „component sawing” może dać nawet dochód
dochodzący do 170 €/m3. Każdy z typów przetarcia wymaga stosownego, bardzo
kosztownego wyposażenia, a także właściwie zorientowanego oprogramowania.
Kolejne referaty były już wygłaszane podczas obrad plenarnych w następujących sesjach tematycznych:
–– nowatorskie procesy obróbkowe (m.in. termowygładzanie drewna – tzw. thermo-smoothing, zastosowanie laserów do cięcia drewna i materiałów drewnopochodnych),
–– charakterystyka pił tarczowych oraz formowanie wióra,
–– materiały narzędziowe i ich zużycie,
–– monitorowanie procesu obróbkowego,
–– siły i opory skrawania (z uwzględnieniem zastosowania mechaniki pękania do
prognozowania efektów energetycznych),
–– szlifowanie – ocena powierzchni obrobionej,
–– produkcja komponentów drewnianych,
–– hałas i zanieczyszczenie środowiska pracy,
–– frezowanie i skrawanie obwodowe,
–– stolarka i produkcja mebli.
W każdej z wyżej wymienionych sesji wygłaszano od 3 do 4 referatów. Sesjom plenarnym, które odbywały się równolegle w dwu audytoriach towarzyszyła
również tzw. sesja plakatowa (25 plakatów) Sesja plakatowa była poprzedzona
krótkim wprowadzeniem, w którym przedstawiciel autorów plakatu mógł zainteresować i zachęcić uczestników konferencji do odwiedzenia stoiska z jego plakatem. Ta formuła prezentacji plakatów prawdopodobnie będzie podtrzymywana
w następnych spotkaniach seminaryjnych. Wielu uczestników oczekuje również,
że sesja plakatowa będzie rozszerzona tak, aby obrady plenarne, podczas których
będą przedstawiane najbardziej wartościowe pod względem naukowym referaty,
82
Kazimierz A. Orłowski
toczyły się w jednym miejscu, a nie równolegle. Będzie to jednak, zdaniem autora, duże wyzwanie dla Komitetu Doradczego seminarium.
Część referatów miała głównie charakter poznawczy, który pozwala lepiej
zrozumieć procesy skrawania drewna. Jednym z nich było wystąpienie Matsa Ekevada (Luleå) na temat formowania wiórów podczas przecinania drewna
piłami tarczowymi, który w imieniu własnym i współautorów przedstawił wyniki badań doświadczalnych, przeprowadzonych za pomocą specjalnych pił na
stanowisku laboratoryjnym. Dzięki zastosowaniu kamery typu high speed, pozwalającej zarejestrować 40000 klatek/s, możliwe było zaobserwowanie, w strefie skrawania, różnic w kształtowaniu wiórów w zależności od rodzaju drewna
i geometrii piły. Oprócz tego, do tej kategorii można też zaliczyć referat J. Sandaka z CNR-IVALSA (National Research Council of Italy – Timber and Trees
Institute) przedstawiający modelowanie struktury geometrycznej powierzchni
drewna (chropowatość, falistość), w którym ujął on nie tylko kinematyczne warunki strugania obwodowego drewna, lecz również zachowanie się elementów
układu OUPN (Obrabiarka – Uchwyt – Przedmiot – Narzędzie, tj. drgania, bicie
narzędzia), a także strukturę anatomiczną obrabianego drewna.
Z kolei część referatów miała znaczenie utylitarne. Przykładowo, Toru Minami z Kanefusa (Japonia) wykazał, że pokrycia wielowarstwowe ostrzy piły
tarczowej z CrN (azotek chromu) wykonane metodą PVD (Physical Vapour
Deposition) są bardziej wytrzymałe, aniżeli te same warstwy jednopowłokowe.
Do tej grupy referatów należałoby również zaliczyć wystąpienie autora, który w
imieniu współautorów i własnym wykazał, że istnieją potencjalne korzyści w postaci oszczędności materiałowych (większa wydajność materiałowa) w wyniku
zastosowania pił tarczowych nowego typu, znanych pod rynkową nazwą Ekomultiks. Wspomniane piły posiadają specyficzną budowę rowków wiórowych, zabezpieczającą korpus piły przed niepożądanym przepływem wiórów pomiędzy piłą
a utworzonym rzazem.
Na zakończenie należy stwierdzić, że niniejszy przegląd referatów z tegorocznego 20. International Wood Machining Seminar nie wyczerpuje oczywiście całej
tematyki, jaka pojawiła się na sesjach plenarnych oraz plakatowych. Jednakże,
daje możliwość zapoznania się z tym, jakie są tendencje i kierunki badań, które być może znajdą w przyszłości swoje trwałe miejsce w przemyśle, w postaci
nowych lub ulepszonych technologii w mechanicznej obróbce drewna. Zainteresowani mogą zapoznać się z pełnym naukowym programem seminarium na internetowej stronie konferencji pod adresem http://www.ltu.se/cms_fs/1.79303!/file/
PROGRAM%20on%20IWMS20.pdf (dostęp: październik 2011).
Aktywny od wielu lat udział autora w tych ważnych spotkaniach zaowocował
zaproszeniem go do International Advisory Committee of the International Wood
Machining Seminar (Międzynarodowy Komitet Doradczy).
Następne, 21. Seminarium Obróbki Drewna odbędzie się w 2013 roku w Tsukubie (Japonia).
20. Międzynarodowe seminarium mechanicznej obróbki drewna w Szwecji
83
20th INTERNATIONAL WOOD MACHINING SEMINAR
Summary
At the beginning of June 2011 in Skellefteå in Sweden the 20th International Wood Machining Seminar was being held. Numerous papers, presented by the leading international
researchers and practicing engineers during both plenary and poster sessions, were in the
character of theoretical, experimental and also utilitarian works.
Keywords: wood machining, seminar, conference
Andrzej Fojutowski, Władysław Strykowski
1
FTP-C7 – SESSION OF THE EUROPEAN FOREST-BASED
SECTOR TECHNOLOGY PLATFORM (FTP) IN WARSAW
For the first time Warsaw hosted a conference of the Forest-Based Sector Technology Platform (FTP). The seventh FTP conference entitled “Pacing Innovation for
the Bioeconomy” was organised on September 26-27, 2011. The issues addressed
at the conference focused on the stimulation of innovative activity in the forest-based sector, increasing the importance of research for the sector’s development,
the intensification of participation in EU framework programmes, and the modernisation of a vision of the sector’s development, taking into account topics outlined
in the currently-drawn EU framework programme “HORIZON 2020”.
Keywords: conference, forest, wood, bioeconomy, innovation, strategy
For the first time a plenary meeting of the European Forest-Based Sector Technology Platform (FTP) was organised in Poland in conjunction with the Polish
presidency of the European Union. Patronage of the seventh conference entitled
“Pacing Innovation for the Bioeconomy” was taken by the Minister of Economy,
Minister of Science and Higher Education, and the Minister of the Environment.
The conference was held on 26-27 September 2011 in Warsaw. The main organiser of the event, i.e. FTP, was supported by local organisers, which were the Wood
Technology Institute in Poznan, coordinator of the Polish Technology Platform
for the Forestry-Wood Sector (PPTSL-D) and organiser of an EU Framework Programmes Industry Contact Point “Forest-Wood”, and the Forestry Department
of Warsaw University of Life Sciences. The Polish State Forests (the State Forest Holding) also marked its presence at the conference. It is worth adding that
the conference title emphasised the importance attached by the EU to the necessity of stimulating and strengthening European activity and place in the area of
innovation, as well as making the most of the potential of forest management,
the advantages of which are natural forces and reserves.
Andrzej Fojutowski, Wood Technology Institute, Poznan, Poland
Władysław Strykowski, Wood Technology Institute, Poznan, Poland
86
The conference was attended by around 120 participants from most of the
EU member states. Among them were representatives of FTP executive bodies,
national support groups of FTP, leading European and global companies and concerns of the forestry-wood industry and related industries, European associations
and networks of entrepreneurs, R&D institutions, and institutions from the business service area.
The conference was preceded by the “Early Stage Researchers’ Forum”
co-organised by FTP and COST (domain: Forests, their Products and Services
(FPS)). The forum was an initiative of the scientific network InnovaWood (wood
technology) and its co-organisers were the European Fibre and Paper Research
Organisation (EFPRO) (research on pulp and paper) and the European Forest Institute (EFI) (forestry).
The conference was opened by a representative of the Polish government –
Maciej Banach, undersecretary of state in the Ministry of Science and Higher
Education. On behalf of FTP the conference participants were welcomed by the
president of FTP High Level Group and president of Arctic Paper SA – Michał
Jarczyński. The conference subject matter was divided into five sessions that concerned developmental trends in the European forestry-wood sector, stimuli of its
development, an innovation support system, future lines of research, and the role
of innovation in industries of the forestry-wood sector (details of the programme
can be found at www.forestplatform.org; www.itd.poznan.pl).
The first part of the conference moderated by Michał Jarczyński focused
on the issues of resources of raw materials originating from the forest, the role
of innovation in the Canadian forestry-wood production system, which enabled
international comparisons of the future of products based on forest raw materials
by 2035 as well as a possibility for multi-industry co-operation in that area.
The second session on forestry-wood sector mobilization (chair – Konstantin von Teuffel, Forest Research Institute, Baden-Württemberg, Germany) was
devoted to discussion of the need for verification of the FTP Strategic Research
Agenda, the place of research, innovation, and bioeconomy in EU scientific policy, and also the strategy concerning EU innovations in relation to the forestrywood sector.
In a further part of the conference devoted to innovation support systems
(chaired by Jan Lagerström, President of FTP Advisory Committee, Sweden), papers concerning the following issues were presented: FTP’s future, experience
gained during the execution of the Star-COLIBRI project, activity of FTP National Support Groups in post-planned economics, and the results of ERA-Net
activity, i.e. EFIMed and WoodWisdom-Net2.
The following session focused on outlining research lines in the forestrywood sector (moderator Bartłomiej Mazela, Wood Technology Department of the
Poznan University of Life Sciences, Poland). During the session the conference
participants were acquainted with such issues as breakthrough results of research
FTP-C7 – Session of The European Forest-Based Sector Technology Platform (FTP) in Warsaw
87
on ionic liquids in new technologies for the forestry-wood sector, a vision of the
future of electronic and intelligent paper, the importance of spinning of carbon
fibres from lignin, and the issue of managing innovative solutions in the wood
industry with the example of developmental initiatives among SMEs in the production of wooden structures.
The session on the role of innovation in industries of the forestry-wood sector
(moderator Teresa Presas, General Director, CEPI, Brussels, Belgium) encompassed a broad spectrum of diverse research results and their implementation
in industry. The session featured IT tools for the virtual presentation of furniture
products and their customisation, innovative solutions concerning paper recycling, and the business experience of Domsjö Biorefinery.
The presentations made by two Schweighofer Prize 2011 winners attracted
much interest. One of the presentations concerned innovative joints for the production of linear structures from glued wood without length limit, and the second
tidal power plants with turbine blades made of layer-glued wood (Glulam).
A further interesting element of the conference consisted of the presentations
of the two best speeches chosen during the “Early Stage Researchers’ Forum”.
The presentations concerned “Environmental benign wood protection by means
of electro osmotic pulsing technology (PLEOT)” (Erik Larnøy, the Norwegian
Forest and Landscape Institute (NTI)) and “Can carbohydrates be used to dictate
structure in native lignins? Towards a more homogeneous technical lignin” (Martin Lawoko, the Royal Institute of Technology (KTH), Sweden).
The presentations and discussions were dominated by issues concerning the
stimulation of innovation in the forestry-wood sector and increasing the role and
importance of research in the sector’s development. Much emphasis was placed
on the need for intensification of participation of industry and scientists from the
forestry-wood area in EU FP7 calls. The necessity of modification of the FTP
Strategic Research Agenda in co-operation with representatives of particular countries was also considered an important issue. Changes in the Agenda should
take into account current visions outlined in the future framework programme
HORIZON-2020. The closing accent of the conference was the study tour to Białowieża Nature Reserve. It is worth adding that the next FTP conference will
be organised in one and a half years, i.e. in spring 2013, in Spain.
88
FTP-C7 – OBRADY EUROPEJSKIEJ PLATFORMY
TECHNOLOGICZNEJ SEKTORA
LEŚNO-DRZEWNEGO W WARSZAWIE
Streszczenie
Po raz pierwszy Warszawa była miejscem obrad Europejskiej Platformy Technologicznej
Sektora Leśno-Drzewnego (Forest-Based Technology Platform – FTP). Siódma konferencja FTP zatytułowana „Pacing Innovation for the Bioeconomy” odbyła się w dniach
26-27 września 2011 roku. Problematyka konferencji koncentrowała się na pobudzeniu
działalności innowacyjnej w sektorze leśno-drzewnym, wzroście znaczenia badań w jego
rozwoju, intensyfikacji uczestnictwa w programach ramowych Unii Europejskiej oraz
modernizacji wizji rozwoju sektora z uwzględnieniem celów zarysowanych w tworzonym
obecnie ramowym programie badawczym UE – HORYZONT 2020.
Słowa kluczowe: konferencja, las, drewno, biogospodarka, innowacje, strategia
Ewa Ratajczak1
EARLY STAGE RESEARCHERS FROM THROUGHOUT
EUROPE PRESENTED THEIR RESEARCH
IN FORESTRY-WOOD SCIENCES
The Early Stage Researchers’ Forum was an accompanying event to the international conference of the European Forest-Based Sector Technology Platform (FTP)
organised on 26-27 September this year in Warsaw. The forum created a good opportunity for researchers at the start of their scientific careers to present the results
of research in the area of wood science and forestry. More than twenty short presentations provided an overview of the research currently conducted at European
universities and in science centres.
Keywords: wood science, forestry, research, early stage researchers
The present scientific policy attaches much attention to the creativity of young
people who have just started their scientific careers. This group of researchers
has a large creative potential and a vested interest in the future of the scientific
domains they are active in. In wood science and forestry that drive was expressed in the Early Stage Researchers’ Forum organised on 26th September 2011
in Warsaw, under the auspices of COST (Cooperation in Science and Technology)
and FTP (Forest-Based Sector Technology Platform). The COST-FTP Early Stage Researchers’ Forum was an initiative of InnovaWood (wood technology) and
other research organisations such as EFPRO (pulp and paper research) and EFI
(forestry), organised in conjunction with an FTP Conference “Pacing Innovation
for the Bioeconomy” within the framework of the Polish presidency of the EU.
The approximately 80 participants of the Forum came from 23 European countries. 23 presentations were given by researchers from 15 countries. Those researchers represented universities, private research institutes and other research
entities. The audience consisted of representatives of universities, companies,
industry federations, and governmental bodies.
The Forum was opened by Ewa Ratajczak, President of InnovaWood and
a representative of the Polish NSG of FTP, followed by a presentation by Matthias
Ewa Ratajczak, Wood Technology Institute, Poznan, Poland
90
Ewa Ratajczak
Haury, the Head of Science Operation at the COST Office in Brussels, who gave
a broad overview of the COST structure and activities.
Following this, the early stage researchers presented their research in the form
of short presentations. The session was moderated by Werner Förster, Secretary
General of EFPRO. All the presentations are now available at www.ftp-c7.eu;
www.innovawood.com and www.itd.poznan.pl.
The subject matter of the research (and the presentations) was very broad and covered the whole forestry-wood chain. In the area of forestry, the issues addressed included: extending large-scale forest inventories to non-forest areas, designing forest management plans for protected areas,
bundling or stacking payment for environmental services, the wood properties of some species (Castanea sativa, Dipteryx panamensis), possibilities of developing wood resource bases (new methods and instruments for
the identification of forest reproductive material, an assessment system for
the evaluation of potential biomass residues, coppice restoration). Among the
wood technology issues discussed we could find:
–– the improvement of conventional kiln drying of sawnwood,
–– environmental benign wood protection by means of electro osmotic pulsing
technology,
–– simultaneous shaping and fixation of veneer by specific material modification,
–– novel green building composites (properties, design and Life Cycle Assessment),
–– load-bearing constructions using poplar and willow wood,
–– a method for estimating the efficiency of chemical pre-treatment for microand nanocelullose production,
–– towards a more homogeneous technical lignin using carbohydrates,
–– the performance of a surface coating made from liquefied wood,
–– cationisation of hemicelluloses and their use in paper pulp,
–– flexible automation in furniture manufacturing using dual-armed manipulators,
–– intelligent chair development for healthy office work.
Having listened to all the presentations, the audience voted for the best ones.
The winners were Erik Larnøy from the Norwegian Forest and Landscape Institute (NTI) with the presentation entitled “Environmental benign wood protection
by means of electro osmotic pulsing technology (PLEOT)” and Martin Lawoko
from the Royal Institute of Technology (KTH) with the presentation entitled “Can
carbohydrates be used to dictate structure in native lignins? Towards a more homogeneous technical lignin”. The award for the winners was the opportunity to
present their research results at the main conference session on “Research Trends
in the Forest-Based Sector” held on the second day of the FTP conference.
At the forum the emphasis was placed on the fact that in the modern world
characterised by a hectic pace of changes, new ideas having a bearing on quality
Early stage researchers from throughout Europe presented their research in forestry-wood sciences
91
of life are now needed, and due to their complex nature they should be developed
by multidisciplinary teams. Therefore, co-operation as well as quick and constant
communication are very important, not only between research networks in the
forest-based sector, but first of all between the science sphere and industry.
Taking advantage of the experience gained in Warsaw and taking into account the recommendations of the COST representative, the organisers would like
to arrange another such side-event for researchers, in conjunction with the next
FTP conference in 2013 in Barcelona, in order to put researchers in contact with
industry representatives and policy makers.
MŁODZI NAUKOWCY Z CAŁEJ EUROPY
O WYNIKACH WŁASNYCH BADAŃ Z ZAKRESU LEŚNICTWA
I DRZEWNICTWA
Streszczenie
The Early Stage Researchers Forum (Forum Młodych Naukowców) stanowiące imprezę towarzyszącą międzynarodowej Konferencji Europejskiej Platformy Technologicznej
Sektora Leśno-Drzewnego, która odbyła się 27-28 września 2011 roku w Warszawie,
stworzyło dobrą okazję do przedstawienia wyników badań z dziedziny drzewnictwa
i leśnictwa przez osoby będące na początku kariery naukowej. Ponad dwadzieścia krótkich prezentacji dało przegląd badań prowadzonych aktualnie w europejskich uczelniach i ośrodkach naukowych. Dwie najlepsze prezentacje były przedstawione w trakcie
Konferencji.
Słowa kluczowe: drzewnictwo, leśnictwo, badania naukowe, młodzi naukowcy

drewno - Instytut Technologii Drewna

Transcription

Similar documents

armor core

Warranty Info

Materials Matter - Fort Street Studio

Decking by the pool Go for Ash wood… because less is more

www.FirstColorado.com 18205 Highway 285 Nathrop, CO 81236

Terra Plus Technical Data Sheet

BENEFITS OF OWNING A PERRY HOME

For Sale in North Briarcliff / Sunrise Estates

Manufacturer of Kedel

bohol project A4 size BUILD BACK BETTER BOHOL