CHARACTERIZATION OF FIBER PIASSAVA FROM SOUTH OF THE

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11th International Conference on Non-conventional
Materials and Technologies
CHARACTERIZATION OF FIBER
PIASSAVA FROM SOUTH OF THE
STATE OF BAHIA (Attalea funifera
Mart)
Natasha I.R.Thomas
Ricardo F. Carvalho
Sara P. Agrela
Nadia M. José
Politechnic School
Chemical Institute
NATURAL VEGETABLE FIBERS
• The United Nations General Assembly declared 2009
as the International Year of Natural Fibres (UN,
2006).
• Sustainable alternative
• Technically feasible and offer many positive social
implications.
• Abundantly available and present low density
characteristics, which can be used as a
reinforcement in composite materials.
Taxonomy and uses
3 different palms:
◦ Attalea funifera,
Atlantic forest.
◦ Leopoldinia piassaba,
tropical rainforest.
◦ Natalia Aphandra,
tropical rainforest.
It is often used
◦ in making brooms,
◦ car seat fillings
◦ for other purposes.
Taxonomy of Attalea
funifera Mart
Class: Monocotyledons
Subclass: Arecidae
Order: Arecales
Family: Arecaceae – Palm
family
◦ Genus
Attalea Kunth –
attalea palm
◦ Species Attalea funifera
Mart
◦
◦
◦
◦
Fibers and lees
Attalea funifera Mart
◦ Usually undomesticated
◦ Managed by approximately 2000 smallscale farmers
◦ Over 10,000 tons of this raw material is
extracted annually.
fibers
◦
◦
◦
◦
5m in length,
1mm in diameter
Water-resistant
Investigated as reinforcement in
polymeric matrixes
piassava fibres are a possible reinforcement of polymeric based
composites
This work compares the physical behaviour of piassava fibres and
lees.
Piassava fibres and lees
Individual fibres contain sclerenchyma cells which provide the
plant with mechanical support.
Mechanical properties depend on;
◦ the age and origin of plant,
the nature of the extraction,
refining procedures,
chemical constituents (Vincent, 2000).
Figure 1; Piassava technical fibres
Figure 2; Piassava lees
Piassava fibres and lees were obtained from a broom
industry in southern Bahia
Fibres and lees were washed
with distilled water and vacuum
dried for 48 hours
Caracterization of piassava fibres and
lees (in natura)
PIGNOMETRY
Van
Soest
SEM
TGA
DSC
DRX
110
100
90
0,002
110
0,000
100
80
(68°C)
60
-0,006
Hemicelulose
(301°C)
50
-0,008
40
-0,010
(376°C)
30
Celulose
-0,012
Massa (%)
-0,004
(m %/°C)
Massa (%)
80
70
-0,002
90
-0,002
Água
0,000
Água
(76°C)
-0,004
70
Hem icelulose
60
(302°C)
50
40
-0,008
100
200
300
400
Temperatura (°C)
(a)
500
600
-0,010
(379ºC)
30
Celulose
20
0
-0,006
0
100
200
300
400
-0,012
500
600
Tem peratura (°C)
(b)
Decomposition of hemicellulose observed at 260-320°C.
The decomposition of the cellulose is located at 320-400°C.
73% of the total mass of the fibres and 75% of the lees had decomposed at a
temperature of 600ºC
(m%/°C)
Figure 3 – Thermographic curves with derivatives (DTA) of
a)piassava lees and b) fibres
Lees
Cellulose
Hemicellulose
Heat Flow (u.a.)
endo
Fiber
Water
0
Figure 4; DSC curves
100
200
300
400
500
600
Temperature (ºC)
Endothermic peaks at 300°C and 363ºC – decomposition of
hemicellulose and cellulose respectively
(a)
(b)
Figure 5 –SEM surface images (1200x) of piassava lees and fibres
respectively
•lees cellular arrangement is similar to technical fibres,
•lees have a rougher, more accentuated surface
(a)
(b)
Figura 6 – SEM images (240x) of the fracture surfaces of
piassava lees and fibres respectively
a) Spongier aspect b) densely compacted cellular arrangement
Figure 7: Scanning electron microscopy of transversal section of
piassava lees, 1200x.
Intensidade (U.A.)
Intensidade (U.A.)
0
10
20
30
40
50
2θ (graus)
60
70
80
90
0
10
20
30
40
50
60
70
80
90
2θ (graus)
Figura 9: X - ray diffractograms of piassava lees and fibres respectively.
•Peaks at 2θ can be observed as 16º, 22,06º and 22,71º respectively, confirming the presence of the
cellulose.
•These are characteristics of the crystal polymorph I of cellulose.
•Lees have higher presence of cellulose
•lees have a higher percentage of inorganic constituents with crystalline structures.
Table 1 – Average chemical Composition of the piassava fibres and lees Attalea
funifera Mart.
sample
Hemicellulose %
Cellulose %
Lignin %
Ashes %
fibre
3.49
50.47
45.68
0.36
lees
5.00
54.84
40.12
0.04
sample
Density (g/ml)
Piassava Fibre
1.12
Piassava lees
1.10
Table 2 - Density values
obtained using the pignometry
method
They have similar physicals properties, thermal behaviour, density, and
morphological arrangements, to the fibres.
In additional, they are softer than fibres and easy flowing in the resin transfer
moulding process.
Since the cellulose is the principal constituent with a crystalline structure, it is
the main attributor towards the mechanical properties.
Results from the TGA, DTA, DSC and XRD analyses all confirm similar results,
that piassava lees have a higher cellulose content and therefore suggests that
better mechanical properties can be expected.
Images obtained from SEM also showed a rougher surface which implies that
piassava lees could be an adequate form of reinforcing composite materials
due to a better adhesion between the piassava lees with the composite
matrix.
However mechanical characterization of the lees and also further analyses
incorporating them as a reinforcement in composite materials is necessary in
order to confirm such a hypothesis
Lees from the piassava industry are an important alternative in the
reinforcement of thermoplastic.
ACKNOWLEDGEMENTS
University of Bath
◦ Department of Architecture and Civil Engineering
◦ BRE Centre for Innovative Construction Materials
FAPESB, CNPq and CAPES
Juscelino Bernardes Leal Comércio for
supplying piassava fibres and lees
Thank you for your attention

CHARACTERIZATION OF FIBER PIASSAVA FROM SOUTH OF THE

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