Enhancement of interfacial properties of carbon fiber reinforced polyphenylene sulfide resin by sulfur treatment

Abstract The properties of carbon fiber (CF) reinforced thermoplastic resin composites depend on the physical and chemical interaction between the fibers and the resins. However, surface oxidation is not always necessary. In this study, the interaction between CF and Polyphenylene sulfide (PPS) is enhanced by using an emulsion of reactive sulfur to treat the CF surface. The interlaminar shear strength (ILSS) of CF/PPS composites is experimentally investigated and found to be up to 79.7 MPa, an increase of 36.1% compared to the untreated CF. The enhancement mechanism of the modification method established is inferred. Scanning electron microscope (SEM) and X‐ray photoelectron spectroscopy (XPS) results showed that sulfur etching on the surface of CF generated new functional groups, which improved the interfacial effect, and tightened the bond between CF and PPS. This indicates that sulfur treatment along with sizing must be a simpler method than surface oxidation to promote the interfacial bonding between CF and PPS.