Due to the limitation of surface inertness and wettability of carbon fibers (CF), the adhesion between Poly(ether-ether-ketone) (PEEK) resin matrix and CF is poor, which reduces the mechanical properties of CF/PEEK composites. In order to improve the interfacial performance between PEEK matrix and carbon fiber fabric, sulfonated-polyether-sulfone (s-PSF) was coated as a sizing agent on the surface of the carbon fiber to construct CF/PEEK composite interface. On one hand, the formation of hydrogen bonds between s-PSF and activated CF increases the adhesion between s-PSF and fibers. On the other hand, Good compatibility between S-PSF and PEEK, which improves the interface performance between PEEK and CF. The results showed that the mechanical properties and interface properties of CF/PEEK composite prepared by modified CF were improved to some extent. The flexural strength, flexural modulus, impact strength and interlaminar shear strength of the materials were increased by 57.5 %, 16.7 %, 44.2 % and 39.7 %, respectively. By introducing s-PSF as sizing agent into CF/PEEK composite interface, the comprehensive properties of the material were effectively improved.
