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Reporter : Jia-Lin Lu
Advisor: Cheng-Ho Chen
Date :104/12/22
Introduction
• Bamboo has been widely used in furniture manufacture, construction
material and living tools for thousands of years, due to its fast growth, high
strength and surface hardness as well as easy machinability .
• During the last decade, many research activities have been dedicated to
natural fiber reinforced thermoplastic composites. Especially
polypropylene (PP), polyethylene (PE), polyvinyl chloride (PVC) and
poly(lactic acid) (PLA) matrices composites are gaining increasing interest .
Introduction
• Bamboo fiber or bamboo particle reinforced polymer composites drawing
attention have also been fabricated and investigated.
• However, being hydrophilic because of the hydroxyl, bamboo fibers do not
adhere well to hydrophobic polymer matrices and absorb water from
surrounding media or moisture. The compatibility between bamboo fiber
and polymer matrix is poor leading to a weak mechanical property.
• Therefore, improvement of interfacial compatibility between bamboo fiber
and polymer resin matrix is the key to fabricate PVC/BP composites with
excellent property.
Introduction
• Hydrothermal pretreatment using hot water is an environmental friendly
approach for processing of lignocellulosic biomass due to its advantages of
chemical free, low operational costs and potential on hemicelluloses
dissolution.
• Hydrothermal pretreatment of biomass not only degraded most of the
hemicellulose and part of the cellulose, but also eliminated the sugar, starch,
and protein on the surface of BP, which resulted in a lower molecule
polarity of BP and a better interfacial compatibility with polymer matrix.
Materials
• Moso bamboo (particle size is 200-400 mm)
• Granulated PVC (particle size is 300 mm)
Method
Step 1. About 200 g of moso bamboo particles were immersed in water with a ratio of 1:5 (wt/v).
Step 2. Then, they were hydrothermal treated for different temperatures (120, 140, 160, 180, 200,
220, 240, 260 and 280C) for 30 min in a closed high temperature high pressure autoclave.
The pressure was kept at saturated vapor pressure of each temperature.
Step 3. After that, BPs was cooled to ambient temperature and washed with distilled water for
several times till the color no longer change.
Then, they were dried in a blast drying oven.
Step 4. Closed mould hot compressing technique was used to fabricate PVC/BP composites in this
study.
Moso bamboo particles obtained after surface modification were mixed with PVC at a weight
proportion of 7:3.
Step 5. The mould was preheated at 170°C for 3 min, and pressed at 180°C by a pressure of 10
MPa for 5 min.
Results and discussion –
Composition analysis
Table 1
Composition of the hydrothermal treated BP.
About 1.00 g of sample was ground into fine powder, and the contents of neutral detergent fiber, acid
detergent fiber, acid detergent lignin, and acidinsoluble ash, respectively, were extracted by a series
of solutions and solvents.
Results and discussion Micromorphology of BP
Fig. 1. Surface morphology of BP: a) untreated, b) hydrothermal pretreated at 160°C,
c) hydrothermal pretreated at 200°C, and d) hydrothermal pretreated at 260°C
Results and discussion Mechanical properties
Table 2
Mechanical properties of PVC/BP composites.
Results and discussion Micromorphology of PVC/BP composites
Fig. 4. Micro-morphology of PVC/BP composites: a) Raw BP,
b) 160C hydrothermal pretreated c), 200C hydrothermal pretreated,
and d) 260C hydrothermal pretreated.
Results and discussion –
Thermal behavior of PVC/BP composites
Table 3
Thermal behavior parameters of PVC/BP composites.
Conclusions
• Hydrothermal treatment was employed to modify moso bamboo particles
surface and then reinforced PVC composites.
• Surface texture of moso bamboo particles were changed; hemicellulose,
lignin and pectin were removed, but excess temperature would give rise to
the degradation of cellulose.
• The mechanical properties of BP reinforced PVC composites increased
with the increase of treating temperature, and then decreased.
• Thermal behavior analysis revealed that higher temperature treated
PVC/BP composites had better thermal stability.