EPDM粘度对PP＼EPDM共混物断口形态和冲击性能的影响

用机械共混的方法制备了一系列不同ＥＰＤＭ粘度的ＰＰ／ＥＰＤＭ共混物，对其力学性能和结晶行为进行了表征，并用扫描电子显微镜（ＳＥＭ）研究了共混物冲击样条的断口形态。实验结果表明，ＥＰＤＭ粘度对共混物的冲击强度有较大影响，随着ＥＰＤＭ粘度的增大，共混物的冲击强度出现极大值，而结晶行为的变化则较小，研究共混物冲击样条的断口形态发现，共混物的冲击强度随ＥＰＤＭ粒径的变化出现极大值。

EFFECTS OF MOONEY VISCOSITY OF EPDM ON MORPHOLOGY OF FRACTURED SURFACE AND IMPACT PROPERTY OF PP/EPDM BLENDS

A series of blends of PP/EPDM with different EPDM mooney viscosity were prepared by a twin-screw extruder and their mechanical properties and crystalization behaviour were characterized. The morphology of the frat :ured surface of the blends was studied by SEM. The results show that the mooney viscosity of EPDM strongly affects the impact strength of the blends. The impact strength of the blends increases with the increasing mooney viscosity of rubbers and reaches maximum. The crystalization behaviour of the blends is lightly affected by the EPDM mooney viscosity. Dependence of impact strength on the size and size distribution of EPDM was also studied. When the particle size increases,the impact strength of the blends increases and reaches the maximum.