Influence of chemical treatments on the mechanical and water absorption properties of bamboo fiber composites

Chemical surface modification of woven bamboo mat with maleic anhydride, permanganate, benzoyl chloride, benzyl chloride, and pre-impregnation were carried out. These modified fibers were used as reinforcements in epoxy and polyester matrices. The effects of fiber modification on the tensile, flexural, impact, and water absorption properties of the composites were investigated. Flexural properties of maleic anhydride treated bamboo polyester composites improved by nearly 50%. The tensile strength and modulus of permanganate-treated bamboo polyester composite increased by 58% and 118%. The tensile strength and modulus of benzoylated bamboo fiber polyester composite improved by 71% and 118%, respectively. After benzoylation of the bamboo fiber, the water absorption is 16% for the bamboo-epoxy composite compared to 41% by untreated bamboo-epoxy composite. The water absorption by benzylated bamboo reinforced polyester composite was 16.8% compared to 51% by untreated bamboo-polyester composite. Pre-impregnation improved the mechanical and water resistant properties of both epoxy and polyester-based composites. SEM investigations of the tensile fracture surfaces show that modifications improved the fiber-matrix interaction.