Abstract: In this paper, a vacuum-assisted resin infusion molding process (VARI) was used to prepare continuous carbon fiber reinforced cast (MC) nylon composites by in-situ anionic polymerization of caprolactam. The O/C ratio detailed surface morphologies within the carbon fiber surface as well as the carbon fiber mechanical properties, the surface morphologies and fiber volume fraction of the composite materials were systematically studied in four different carbon fiber fabric surface treatment methods, i.e., acetone desizing treatment, gas phase oxidation treatment, coupling agent treatment and flame treatment. The results indicate that the surface of the carbon fiber is coated with a coupling agent, and the mechanical properties of the composite material prepared by this carbon fiber are better than those prepared by other treatment methods. In this case, the tensile strength reaches 595.5 MPa. The flexural strength reaches 330.7 MPa, and the interlaminar shear strength reaches 30.6 MPa. The carbon fiber surface O/C ratio reaches 44.51%, and the carbon fiber volume fraction of the composite material reaches 51.4%.

Key words: MC nylon, in-situ polymerization, carbon fiber surface treatment, composite material