Pineapple leaf/recycled disposable chopstick hybrid fiber-reinforced biodegradable composites

Abstract

In this study, pineapple leaf fiber and recycled disposable chopstick fiber were chemically treated by alkaline solution and a silane coupling agent (triethoxy-vinylsilane). Then, these hybrid fibers and biodegradable polymers (poly(lactic acid) (PLA) or poly(butylene succinate) (PBS)) were mixed to form hybrid fiber-reinforced green composites. These hybrid fiber-reinforced biodegradable polymer composites will be fully biodegradable. Moreover, the usage of hybrid fibers could modulate the properties and prices of the products. SEM analysis shows that the compatibility between the substrate and the reinforcing materials was improved after chemical modification. Moreover, the strong interfacial bonding between the modified fibers and the matrix limited the water absorption of the composites. The results revealed that the composite containing 30wt% of chemically modified hybrid fiber exhibits the best properties. The tensile strengths of PBS and PLA can be improved by 121.7 and 66.1%, respectively. The flexural strengths of PBS and PLA can be all improved by 66%. As to the thermal properties, the heat deflection temperature of PBS and PLA can be increased by about 33.6% and 75%, respectively, with the addition of 30wt% modified hybrid fibers. As well as enhancing the mechanical properties and thermal stability, the reinforced composites are more environmentally friendly than the artificial additive-reinforced ones. The waste from the pineapple leafs and recycled chopsticks is effectively reduced and re-used, and the cost of materials lowered.