Properties of injection molded in situ composites based on PPS and a melt processable glass

This work was concerned with evaluating the properties of injection molded composites consisting of polyphenylene sulfide (PPS) reinforced with variou s loadings of a melt processable phosphate glass. During injection molding both the PPS and melt processable glass were deformable, facilitating the p rocessing of higher glass loadings than are possible in conventional solid glass fiber reinforced materials. The stiffness of the composite blends was found to increase with glass concentration with a composite containing 60 wt% (44 vol%) phosphate glass showing moduli over 4 times greater than that of the neat PPS. Composites possessing stiffness comparable to a conventio nal E-glass reinforced material (40 wt% fiber) could be produced utilizing higher phosphate glass loadings on the order of 60 wt%. While the addition of the phosphate glass led to significant enhancements in the stiffness of the composites, the strength of the blends often fell to values below that of the near resin. Although the use of phosphate glass typically resulted i n strengths 2-3 times lower than those found for the E-glass filled materia l, these composites offered several advantages including lower anisotropy i n mechanical properties, lower viscosities, and smoother surfaces.