两种丙烯聚合用球形Ziegler-Natta催化剂的性能研究

Study on Properties of Two Spherical Ziegler-NattaCatalysts for Propylene Polymerization

采用扫描电子显微镜、激光粒度仪、密度仪和熔体流动速率仪(MFR)等研究了2种丙烯聚合用球形齐格勒-纳塔(Ziegler-Natta)催化剂(记为1#和2#)的性能。结果表明:与2#相比,1#的平均粒径更小,粒径分布更宽,活性更高,对氢气更敏感,且所得聚丙烯(PP)堆积密度更高,但PP颗粒粒径较小。不同外给电子体对丙烯聚合的影响不同。采用二环戊基二甲氧基硅烷为外给电子体时,2种催化剂活性均最高,所得PP的MFR均最小。

The properties of two spherical Ziegler-Natta catalysts(referred to as 1#and 2#)for propylene polymerization were investigated by scanning electron microscopy,laser particle size analyzer,densitometer and melt flow rate analyzer(MFR).The results show that compared with 2#,1#has a smaller average particle size,a slightly wider size distribution,higher activity and is more sensitive to hydrogen,the resulting polypropylene(PP)has a higher packing density,but the PP particle size is smaller.Different external electron donors have different effects on propylene polymerization.When using dicyclopentyldimethoxysilane as the external electron donor,both catalysts have the highest activity and MFR of the resulting PP is the smallest.