Effects of liquid crystal polymer (LCP) on the structure and performance of PEEK/CF composites

Carbon fiber reinforced polyether ether ketone (PEEK/CF) composites feature diverse advantages and have been applied in various fields. However, the high melt viscosity of PEEK leads to their poor processing performance and affects their practical applications. Here a liquid crystal polymer (LCP) was introduced into a PEEK/CF system as a new strategy to address the aforementioned issues. Bearing aromatic rings on the main chains, LCP can strongly interact with PEEK by pi-pi interaction, which alters the crystallization behaviour and facilitates processing of PEEK/CF, eventually improving its mechanical performance. As a result, a high crystallinity (37.37%), a decreased equilibrium torque (8.902 Nm), and a high tensile strength (230.97 MPa) are realized with 5 wt% LCP. The current approach offers a new solution to simultaneously promote processing and mechanical performance of PEEK/CF and other polymer-based composites.