Abstract: Carbon fiber reinforced thermoplastic resin-based composite materials have been paid more and more attention in many fields such as aerospace and automotive industries due to their excellent performances such as light weight, high strength, short processing cycle and recyclable recycling. They have also become important developments in future composite additive manufacturing direction. In order to solve the problems of high energy consumption and difficult solvent removal in the preparation of composite prepreg by solution method, solvent volatilization causes environmental pollution and harm to human health, this paper uses high performance thermoplastic resin polyethersulfone (PES). As a substrate, the solution is removed by a solution dipping-phase transformation method at a normal temperature to remove the solvent at a normal temperature, and the method is energy-saving and environmentally friendly. Thermoplastic prepreg yarns with controlled resin content, good flexibility, and possibility for three-dimensional weaving and automatic placement molding are prepared by solution impregnation-phase transformation. It is thermoformed into an unidirectional tape sample, which is compared with the thermal properties and mechanical properties of common epoxy resins and their composite materials. It is found that the PES-based composite material has excellent heat resistance. Its thermal decomposition temperature (T_5%) is 576 ℃, the residual carbon ratio (N₂) at 800 ℃ is 90%, and the longitudinal tensile strength of the unidirectional belt can reach 1781 MPa. The tensile modulus is 60.17 GPa. Although it is slightly lower than the epoxy resin matrix composite of the same resin content, but the PES-based composite material is a high-performance thermoplastic composite material with great development potential.

Key words: continuous carbon fiber, polyethersulfone, phase inversion, prepreg, thermoplastic composite