Study On Polyphenylene Sulfide Friction Composites

The application and the demand of market of Polyphenylene sulfide (PPS) which was one of the specially engineering plastics with the highest proportion of properties and price were enlarged because of its outstanding combination properties. As one of heat-resistant polymer fiiction materials, it was necessary and significative to exploit and study on PPS friction composites, and to analyze their mechanism of wear.The friction and wear properties as well as the mechanical properties of PPS composites which filled with graphite, nano-inorganic particles, polytetrafluoroethylene (PTFE) and liquid crystalline polymer (LCP) were studied in the paper. To analyze the mechanism of wear and the dispersion of fillers, the worn surfaces and fracture surfaces of PPS composites and the tool steel counterface were observed by means of scanning electron microscope (SEM). The contributions of the fillers for crystallization of materials were also investigated by differential scanning calorimeter (DSC).The following conclusions can be drawn from the paper:1. The addition of graphite was contributed to forming the transfer debris on the tool steel counterface. The friction coefficient of PPS composites decreased obviously but the wear loss of them enhanced with the increasing proportions of graphite. The fiiction and wear properties were altered slightly with varying of graphite particle size. The wear loss of composites were mainly caused by abrasive particles. The crystallinity and velocity of crystallization of the composites were increased owing to the presence of graphite which acts as nucleating agent during PPS crystallization.2. The fiiction coefficient of the composites was decreased when PPS was filled with Al₂O₃ or SiO₂ nanoparticles. However, the frictional behaviors and mechanical properties of the...