In-situ spray impregnation of poly(pentamethylene oxamide) onto carbon fibers and their composites

Polyoxamides are a class of polyamides that exhibit superior mechanical, chemical, UV light resistance, and low water absorption properties than their conventional counterparts. In this study, a novel in-situ spray polycondensation techniques is developed and used to impregnate poly (pentamethylene oxamide) (PA52) prepolymer into carbon fibers (CF). The prepolymer impregnated CFs are subjected to solid state polycondensation to increase the molecular of PA52 resin thus obtain prepregs for fabrication of carbon fiber reinforced polyoxamide composites. The effects of preparation parameters on the mechanical properties of PA52/CF composites are studied and reported. The results showed that, PA52/CF composites prepared at molding temperature of 325°C, pressure of 3.0 MPa, and time of 10 min exhibits good tensile strength at break, flexural strength, and interlaminar shear strength (ILSS) of 435 MPa, 364 MPa, and 51 MPa, respectively. SEM results suggest good adhesion between the PA52 and CF which is supported by the high storage modulus results obtained from dynamic mechanical analysis (DMA) results, depicting the potential of in-situ spray impregnation in preparation of carbon fiber reinforced polyoxamide composites.