Surface modification by air-plasma treatment and its effect on the tribological behavior of hybrid fabric-polyphenylene sulfide composites

摘要

Untreated and air-plasma-treated hybrid polytetrafluoroethylene (PTFE)/poly(p-phenylene terephthalamide) (Kevlar) fabrics were used to prepare hybrid fabric-polyphenylene sulfide (PPS) composites by dip-coating in a PPS suspension followed by hot pressing at 295C for 5 minutes. The tribological properties of the resulting composites were evaluated on a MPX-2000A friction and wear tester with an end-face contact mode. To investigate the surface changes, untreated and treated hybrid fabrics were characterized by using a single fiber tensile test, fabric bonding property test, Fourier transform infrared spectroscopy, scanning electron microscopy, and water contact angle measurements. The results indicated that the air-plasma treatment could significantly improve the tribological behavior of the hybrid fabric-PPS composites. Moreover, the impact of the air-plasma treatment power and time on the tribological properties of the hybrid fabric-PPS composites was systematically studied. An optimum condition of the air-plasma treatment for our equipment was 120 W and 10 minutes. Active carbonyl (CO) groups were introduced on the surface after the treatment, coupled with an increase in the surface roughness, both of which improved the tribological properties of the hybrid fabric-PPS composites by strengthening the bonding property among the hybrid fabric, PPS, and substrate. On the other hand, excessive air-plasma treatment of the hybrid fabric weakened the tribological properties of the hybrid fabric-PPS composites.