GLASS FIBER REINFORCED THERMOPLASTIC COMPOSITES Effect of Polyamide Blend on Fiber/Matrix Interfacial Properties of Glass Fiber Reinforced Thermoplastic Composites

Glass fiber reinforced thermoplastic composites (GFRTP) containing various thermoplastics blended together as the matrix resin have been studied in order to give diverse properties to GFRTP. The mechanical properties of GFRTP are greatly affected by the fiber/matrix interface. However, previous studies on GFRTP using blended thermoplastics have not clarified the interfacial properties between the thermoplastics and the fibers, such as how the blended thermoplastics form the interface with the fiber, In this study, model composites made of various polyamide blends and fibers were prepared, and SEM observations and single fiber pull-out tests were conducted to clarify the distribution of each polyamide at the fiber/matrix interface, the factors of the polyamide that affect this polyamide distribution, and the effect of the polyamide blend on the fiber/matrix interfacial shear strength. In the fiber/matrix interface, when the crystallization temperature difference between the polyamides that constitute the matrix resin is large, the polyamide with the higher crystallization temperature becomes more abundant, and the interfacial shear strength measured by the single fiber pull-out test reflects the interfacial strength of this more abundant polyamide. In GFRTP using blended resins, it is considered possible to control the fiber/matrix interfacial properties by controlling for the crystallization temperature of each resin in the matrix.