Investigation On The Thermodynamics And Mechanical Properties Of Cabon Fiber Reinforced Pps Hybrid Composite Materials

Compared with FRP (fiber reinforced thermosetting plastics), FRTP (fiber reinforced thermoplasticity plastics) have good toughness properties, easy processing, reusable properties and has accepted more and more people’s attention. Polyphenylenesulfide (PPS) is an attractive matrix material in manufacturing FRTP, because of its chemical resistance, electrical insulating ability, self excellent flame retardant and high temperature durability. In this article, CF reinforced PPS prepregs was prepared in the twin-screw extruder. PPS/CF composites was made by injection molding. The evolution of PPS and molding techniques, melt crystallization, thermal degradation, dynamical mechanic thermal properties, mechanical properties, friction and wear properties of PPS/CF were investigated through differential scanning calorimeter (DSC), differential thermal analysis (DTA), scanning electron microscope (SEM), dynamic mechanical analysis(DMA), capillary rheometer, friction wear testing machine, universal testing machine. The relationships with structures and the properties of thermal and mechanical behavior were mainly discussed.It had been found that the viscosity of PPS melt was decreased with the rise of temperature. From290℃to340℃, viscosity of higher molecular weight of PPS were higher and more sensitive to temperature than lower. The author prepared the PPS/CF of different contend of CF with changing the screw speed of double screw extrusion machine and contend of CF. CF in the PPS/CF prepreg scattered in good effect and orientated along the extruding. Screw speed had crucial influence on the CF contend of PPS/CF, but it had little impact on the length and diversification effect of CF.CF acted as heterogeneous nucleation agent in the crystallization process of PPS, which could increase the crystallinity and crystallization temperature and make the crystallization peek shift to high temperature. PPS and PPS/CF had good thermal stability in nitrogen. The glass transition temperature of PPS increased as a result of the introduction of CF. Crystallization peek of PPS and PPS/CF shifted to higher temperature and became wider and crystallinity decreased while cooling rate increased. The Ozawa and Mo equation was used to analyze the non-isothermal crystallization kinetics of PPS. The results showed that Mo equation was more suitable to describe and analyze the non-isothermal crystallization kinetics of PPS than Ozawa equation.Tensile strength and flexural strength of PPS/CF were higher than those of PPS. With increase of contend of CF, impulse strength increased first and then decreased. The results showed that the mechanical properties of PPS/CF was the best, with the containing19.68wt%CF. Tensile strength increased to115.55MPa from55.59MPa. Flexural strength increased to115.55MPa from55.59MPa. Impulse strength decreased to47.34MPa from56.48MPa.When PPS/CF was made by injection molding, the edge of the distribution of CF was different from the center.With the addition of CF, the property of wear-resisting of PPS was improved and the friction mechanism of PPS was changed. Friction mechanism of PPS was extrusion and adhesive transference, however friction mechanism of PPS/CF was abrasive wear. With increase of contend of CF, wear rate and friction coefficients of PPS/CF was decreased. The results showed that the property of wear-resisting of PPS was the best, with the containing19.68wt%CF. Friction coefficients dropped from0.675to0.2. Wear rate dropped from2.4×10-6mm(Nm)-1to0.3×10-6mm(Nm)-1.