Carbon fiber reinforced plastics (CFRPs) have been attracting attention in the automotive industry for their lightweight related properties. Thermoset plastics are mainly used as matrices in CFRPs in the aerospace industry. A thermosetting resin takes a long time to mold and this results in high costs. On the other hand, carbon fiber reinforced thermoplastics (CFRTPs) are recyclable, good in relation to productivity and excellent with regard to impact strength. Thus, they are expected to be widely applied within the industry. Polycarbonates (PCs) have excellent impact resistance which does not change even at low temperatures. Therefore, a PC can be expected to be applied as matrix in a CFRTP. A PC with higher-molecular-weight improves CFRTP's impact resistance, but at the same time, increases its viscosity and deteriorates the impregnation of continuous fibers. Therefore, improvements in moldability of CF/PC are required. To improve the quality of the molded CF/PC, CF/PC thermoplastic prepregs, in which carbon fabrics or unidirectional carbon sheets are pre-impregnated with PC, were developed. In this study, carbon fiber reinforced polycarbonate (CF/PC) laminated composites were molded with unidirectional sheets of thermoplastic prepregs; the moldability and mechanical properties of CF/PC laminated composites were evaluated.

Carbon Fiber Reinforced Plastics (CFRP) have been attracting attention in the automotive industry for their light-weighted properties. Thermoset plastics are mainly used as a matrix of CFRP in the aerospace industry. Thermosetting resin takes a long time for molding and this results in high costs. On the other hand, Carbon Fiber Reinforced Thermoplastics (CFRTP) are recyclable, good in productivity and excellent in impact strength. Thus, they are expected to be widely applied within the industry. Polycarbonate (PC) is excellent in impact resistance that does not change even at low temperatures. Therefore, PC can be expected to be applied as matrices of CFRTP. PC with higher-molecular-weight improves its impact resistance, but at the same time, increases its viscosity and deteriorates impregnation of the continuous fibers. Therefore, improvements in moldability of CF/PC are required. To improve the quality of the molded CF/PC, CF/PC thermoplastic prepreg, in which carbon fabrics or unidirectional carbon sheets are pre-impregnated with PC, were developed. In this study, carbon fiber reinforced polycarbonate (CF/PC) laminated composites were molded with thermoplastic prepregs of unidirectional (UD) sheets; moldability and mechanical properties of CF/PC laminated composites were evaluated.

Carbon Fiber Reinforced Thermoplastics (CFRTP) attract attention in the automotive industry because of their high specific strength and short production cycle. As Polycarbonate (PC) is excellent in terms of impact resistance, dimensional stability and heat resistance, as compared with other thermoplastic resins, it is expected to be used for CFRTP. Although PC with higher molecular weight has better impact resistance, due to its higher viscosity, it is difficult to impregnate into the continuous fibers. Therefore, the effects of molecular weight of PC on mechanical properties of Carbon Fiber Reinforced Polycarbonate (CF/PC) should be investigated. In this study, CF/PC laminated composites were molded with two kinds of PC with different molecular weights, and their moldability and mechanical properties were evaluated. CF/PC using PC with a high molecular weight tended to show a higher void fraction than that with a low molecular weight. CF/PC using PC with a high molecular weight showed higher fiber/matrix interfacial shear strength in single fiber pull-out tests, and this result is considered to be the effect of the larger residual stress to the fiber, due to the larger difference in specific volume of PC with a higher molecular weight. CF/PC using PC with a high molecular weight showed higher interlaminar strength, bending strength, and absorbed energy in impact tests.