Continuous Natural Fiber Reinforced Thermoplastic Composites by Fiber Surface Modification

Continuous natural fiber reinforced thermoplastic materials are expected to replace inorganic fiber reinforced thermosetting materials. However, in the process of fabricating the composite, it is difficult to impregnate the thermoplastic resin into reinforcement fiber because of the high melt viscosity. Therefore, intermediate material, which allows high impregnation during molding, has been investigated for fabricating continuous fiber reinforced thermoplastic composite by aligning resin fiber alongside reinforcing fiber with braiding technique. This intermediate material has been called microbraid yarn (MBY.) Moreover, it is well known that the interfacial properties between natural fiber and resin are low; therefore, surface treatment on continuous natural fiber was performed by using polyurethane (PU) and flexible epoxy (FLEX) to improve the interfacial properties. The effect of surface treatment on the mechanical properties of continuous natural fiber reinforced thermoplastic composites was examined. From these results, it was suggested that surface treatment by PU with low content could produce composites with better mechanical properties.