Improvement of Mechanical Strength of Carbon Fiber Reinforced Syndiotactic Polystyrene Injection Molded Products by Addition of Acid-Modified Poly(2,6-dimethyl-1,4-phenylene ether)

Abstract

We have previously reported that blending syndiotactic polystyrene (SPS) with acid-modified polyphenylene ether (c-PPE), which is compatible with the amorphous chains of SPS, improves the interfacial shear strength between CF. We have also shown that c-PPE, which has higher interfacial shear strength between CF than SPS, is self-localized on the CF surface. However, this selflocalization has been observed under static conditions (static holding in the molten state) in the microdroplet method, but the influence of blending (melt kneading), a dynamic condition, on the interfacial strength has not been clarified. In this report, we investigated the effect of c-PPE addition on the mechanical properties of injection-molded SPS/CF composites by preparing samples at different kneading temperatures in a twin-screw kneader, which is widely used in industry due to its high productivity. The mechanical properties of SPS/CF were improved by the addition of c-PPE, and the effect of adding c-PPE on the mechanical properties of SPS/CF was enhanced at higher kneading temperatures. Higher kneading temperatures promoted the self-localization of c-PPE on the CF surface and increased the chemical interaction at the c-PPE-CF surface.