Effect of Different Enzymatic Treatment on Mechanical, Water Absorption and Thermal Properties of Bamboo Fibers Reinforced Poly(Hydroxybutyrate-co-Valerate) Biocomposites

Improving the adhesion between fibers and polymer matrix is essential for natural fiber composites. The purpose of this research is to investigate the effect of enzymatic treatment on bamboo fibers (BF) reinforced biodegradable plastic composites. Three different kinds of enzymes (pectinase, cellulase, laccase) were used to treat BF, then biocomposites were fabricated by BF and poly(hydroxybutyrate-co-valerate) (PHBV) through melt blending and injection molding process. The modification effects of BF treated with enzymes were evaluated by fourier transform infrared spectroscopy and scanning electron microscopy. Results showed that enzymatic treatment enhanced the mechanical properties of BF/PHBV composites and decreased the water absorption of BF/PHBV composites, whereas the enhancement of mechanical properties is not significant. These improvements are attributed to the interfacial adhesion between BF and PHBV matrix was increased by enzymatic treatment. Comparing the modification effects of the three enzymes, the BF/PHBV composites with pectinase treatment obtained the best mechanical properties and the lowest water absorption. In addition, the thermal stability and crystallinity of BF/PHBV composites increased after enzymatic treatment.