Improvement of interfacial properties of carbon fiber-reinforced poly(phthalazinone ether ketone) composites by introducing carbon nanotube to the interphase

This article aims to improve interfacial properties of carbon fiber-reinforced poly(phthalazinone ether ketone) (PPEK) composites by means of preparing carbon nanotube (CNT)/carbon fiber hybrid fiber. XPS was used to characterize the chemical structure of unsized carbon fiber and SEM was used to observe the surface topography of carbon fibers. Specific area measurement, dynamic contact angle, and interfacial shear strength (IFSS) testing were performed to examine the effect of CNT on the interfacial properties of carbon fiber/PPEK composites. By the introduction of CNT to the interphase of carbon fiber-reinforced PPEK composites, an enhancement of IFSS by 55.52% was achieved. Meanwhile, the interfacial fracture topography was also observed and the reinforcing mechanism was discussed.