【摘要】 采用超高分子量聚乙烯 (UHMWPE)原位成纤增强、增韧聚丙烯 (PP)。讨论了混炼剪切力、成型冷却方式和UHMWPE熔体粘度对材料力学性能的影响。发现提高剪切力 ,加快冷却速度均有利于力学性能的提高 ,配比为 90 / 10的PP/UHMWPE的缺口冲击强度、拉伸强度和断裂伸长率可达 88 6kJ/m2 、45 1MPa和 570 % ,分别是PP 1330的 3 5倍、1 5倍和 2 5倍 ;而UHMWPE相对分子质量增加所引起的粘度上升则有损改性效果。DSC谱图发现PP 1330的乙烯嵌段与UHMWPE可形成共晶 ,淬冷则可使共晶的含量显著增加 ,从而加强了两相间的结合力。更多还原

【Abstract】 Polypropylene is toughened by in situ fiber forming reinforcing of UHMWPE .The influences of shear stress at mixing,cooling system in molding and melt viscosity of UHMWPE on mechanical properties of composites are discussed. It is found that increase of shear stress and cooling velocity may benefit the enhancement of mechanical properties .The notched impact strength,tensile strength and elongation at break of PP/UHMWPE composites with composition ration of 90/10,can be 88.6kJ/m 2,45 1kpa,and 570%,respectively and correspondingly being 3.5,1.5 and 2.5 time of the value for PP 1330 However.The increase of viscosity resulted from increase of UHMWPE molecular weight will cause damage to the effects of modification.DSC graphs show that the ethylene block of PP 1330 can form co crystals with UHMWPE.Qenching makes co crystal markably increases ,therefore,the inter phase bonding force may be strengthened.\;更多还原