Processing of Carbon Fiber Fabric Reinforced Polycarbonate

Carbon fiber reinforced thermoplastic (CFRTP) is expected to be useful in the automobile applications because CFRTP has some excellent aspects such as relatively light weight, high strength,easiness of recycling etc. Mechanical properties of the CFRTP depend on the impregnation state of the matrix resin into the carbon fiber (CF) bundles. In this study, we discussed the influence of the melting viscosity of the matrix polycarbonate (PC) resin at impregnation time on impregnation state of PC into CF bundles, and also discussed the effect of number and size of void of CF/PC on the flexural properties of the CF/PC. Three kinds of PC with different viscosities were employed as the matrix resin. The CF/PC composites were prepared by heat press molding using the CF plain fabric and PC film using the film stack method. The void fraction of the CF/PC almost linearly decreased with viscosity of PC resin and was independent of the kinds of PC. The flexural strength and modulus of CF/PC increased with decreasing void fraction of the CF/PC. According to the photograph of CF/PC surface, the number of large size of voids in CF/PC decreased with PC viscosity. These results imply that the impregnation of PC matrix into the carbon filaments is improved by using the PC with low viscosity. Then, the matrix viscosity is found to be important characteristics for CFRTP with high performance.