PP三元共混合金的力学性能及结晶行为研究

研究了不同乙烯含量的ＥＰＤＭ对ＰＰ／ＵＨＭＷＰＥ合金的增容作用，并讨论了共混体系结晶行为的变化情况。发现ＥＰＤＭ中乙烯含量的增加可提高增容效果；在ＰＰ／ＵＨＭＷＰＥ／ＥＰＤＭ为１００／１０／６时，共混物缺口冲击强度可达９１．１ｋＪ／ｍ＾２，为ＰＰ的３．５倍，此时拉伸强度仍比纯ＰＰ高４．３ＭＰａ。

THE BEHAVIOR OF MECHANICS AND CRYSTALLIZATION OF PP TRINARY-BLENDING ALLOYS

EPDM was studied as compatibilizer of PP and UHMWPE, and the variation of crystal behaviors of the alloy was also discussed. The results show that the rising of ethylene content in EPDM can improve the compatibility. When the ratio of PP/UHMWPE/EPDM is 100/10/6, the impact strength of notch can reach to 91.1 kJ/m 2, which is 3.5 times of PP and the tensile strength is 4.3 MPa higher.The DSC analysis demonstrates that UHMWPE and ethylene diblock of PP have crystal phase compatibility, at higher decreasing temperature rate UHMWPE crystallizes ahead of PP and become its crystal nucleus making the two composites crystallize simultaneously, and the crystallinity and cryatllization rate of the alloy are both remarkably enhanced by adding EPDM into it. The crystalline patterns prove further the present of the complex cocrystal and show that EPDM has the functions of inserting, deviding and fining to alloy spherocrystal, thus deeply destroyed the perfectibility of crystallization.