高抗冲耐低温聚丙烯合金的制备及其性能

PREPARATION AND PROPERTIES OF HIGH- IMPACT AND LOW-TEMPERATURE RESISTANCE PP ALLOY

介绍了PP/HDPE/SBS(苯乙烯-丁二烯-苯乙烯三元嵌段共聚物)三元高分子合金的制备及其组成,研究了加工工艺对材料力学性能与流变性能的影响。实验表明:适宜的聚合物组成在同向啮合双螺杆共混造粒过程中,采用二阶共混、高剪切速率与低速加料的共混工艺,可研制出室温缺口冲击强度为54.1kJ/m^2、-25℃时缺口冲击强度为10.5kJ/m^2的高抗冲聚丙烯合金材料。由扫描电镜观察可见,HDPE的加入有利于SBS在PP/HDPE复合基体中更均匀的分散和颗粒细微化。所制备的PP/HDPE/SBS高分子合金呈现非牛顿假塑性流体行为。随SBS含量的提高,合金体系流动温度下降、表观粘度上升。同时还讨论了该高分子合金的动态力学性能。

The preparation and formulation of PP/HDPE/SBS(styrene -butadiene -styrene ternary block copolymer) ternary polymer alloy was introduced, and the influences of processing technology on material mechanical and rheology properties were developed. During co-rotating intermeshing twin screw blend pcllctizing, with two-stage blending, high shear rate and low feed rate, high -impact resistance PP alloy which had notch impact strength 54.1kJ/m2 at room temperature and 10.5kJ/m2 at -25 ℃ was prepared from polymers of appropriate formulation. By SEM , it was observed that adding HDPE helped distribution of SBS in PP/HDPE composite basis. The PP/HDPE/SBS polymer alloy had non-Newton pseudo - plastic rheology behavior, and the alloy system flow temperature decreased and viscosity increased apparently with raising the use amount of SBS. The dynamic mechanical properties of this polymer alloy were discussed at same time.