MECHANICAL PROPERTIES OF POLY (LACTIC ACID) BASED BIOCOMPOSITES: COMPARISON OF DIFFERENT REINFORCEMENTS

摘要

The poly (Lactic acid) (PLA) based biocomposites reinforced with different natural reinforcements consisting of bamboo fiber, vetiver grass fiber, coconut fiber, silk fiber and bamboo charcoal powder were prepared and mechanically tested. To enhance the adhesion between reinforcement and PLA matrix, the flexible epoxy resin was selected and used as a novel surface treatment for natural reinforcement. It was found that the stiffness of untreated biocomposites increased significantly. However, the mechanical strengths such as tensile, flexural and Izod impact strength of composites decreased with increasing of reinforcement content. The flexible epoxy surface treatment reduced the stiffness of all composites while it considerably increased the tensile, flexural and impact strength when compared against the untreated composites. However, it can be seen that the effects of flexible epoxy treated on the mechanical strengths improvement were dependent upon the reinforcing fiber. By introducing this treatment better mechanical properties were obtained with the exception of the VF/PLA combination which remained nearly the same. Bamboo fiber proved to be the most effective reinforcement compared to other reinforcements.