The Effect of Surface Modifier on the Mechanical Properties of the Oxysulfate Whiskers/PP Composites

Abstract

The magnesium oxysulfate whiskers/PP composites were prepared by melt-extrusion with modified whiskers as fillers. The mechanical performances including the tensile strength, elongation at break and elastic modulus were tested by electronic universal testing machine.The effect of surface modifier on the mechanical properties of the composites was studied. In general, the mechanical properties of the composites of the zinc stearate modified whiskers/PP were better than it modified by coupling agent KH550. when the contents of the whiskers modified were 20%, the mechanical properties of the composites got the best. There occurred different organic molecule membranes on the surface of the modified whiskers, which lowered the interfacial energy of whiskers. So modified whiskers had different strengthening with PP matrix.

Effect of magnesium oxysulfate (MOS) morphology on the crystallization, mechanical, and rheological properties of polypropylene/MOS composites

“…Jiang and Li 17 observed a slight decrease in tensile strength of PVC/MOSw composite compared with neat PVC. In other study, Jiang et al 8 also found that the tensile strength reduced obviously when MOSw was added into PP matrix. They ascribed it to no chemical bond formed between PP matrix and MOSw.…”

“…Actually, the presence of whisker-shaped MOS (MOSw) at the 1990s greatly promotes its application, especially in polymeric composites area, because of its inherent outstanding mechanical and flame-retardant properties. 6,7 So far, there are many reports about MOSw-reinforced or flame-retarded polymeric composites, such as polypropylene/MOSw (PP/MOSw), 8,9 polyethylene/MOSw (PE/MOSw), 10,11 silicone rubber/MOSw (SR/MOSw), 12 ethylene-vinyl acetate/MOSw (EVA/MOSw), 13 acryonitrile butadiene styrene copolymer/MOSw (ABS/MOSw), 14,15 polyvinyl chloride/MOSw (PVC/MOSw) 16,17 composites, and so on. Almost all these composites exhibited significant improvement in the flame-retardant properties but scarcely enhancing the mechanical behaviors.…”