Effect of short-cut p-aramid fibers on mechanical properties of polyacrylonitrile resin
The surface of short-cut p-aramid fibers was modified with chlorosulfonic acid to introduce—SO2Cl groups.An optimal modification effect was achieved at a chlorosulfonic acid concentration of 40 mmol/L.The fibers were modi-fied by using phenyltriethoxysilane as a coupling agent,and the coupling agent was successfully grafted onto the fiber sur-face.The polyacrylonitrile/p-aramid fiber composites were prepared through in-situ polymerization of modified p-aramid fiber with benzonitrile monomer.The effect of fiber content on the mechanical properties of the composites was investi-gated.The composite obtained optimal mechanical properties at a fiber content of 0.5 wt%,and its storage modulus,glass transition temperature,and bending modulus reached 4,137 MPa,350 ℃,and 4,467 MPa,respectively.