烷氧基氯化钛载体型催化体系用于丙烯聚合反应的研究——Ⅲ.不同烷氧基团对催化剂性能的影响

我们研究了烷氧基氯化钛Ti(OR)_nCl_(4-n)负载于MgCl_2-EB(EB为苯甲酸乙酯)做为丙烯定向聚合反应的催化剂。本文报告不同种类及不同数目的-OR基团对催化剂性能的影响。结果表明,它们能以高活性催化丙烯定向聚合并得到高等规度聚合物,其中以n-C_6H_(13)-OTiCl_3活性最好。由于空间位阻的缘故,-OR基团数目增多,对催化活性和等规度均不利。在钛活性组分中引入烷氧基团,聚合物分子量明显降低。

INVESTIGATION ON THE SUPPORTED CATALYST SYSTEMSOF ALKOXYL TITANIUM CHLORIDE FORSTEREOSPECIFIC POLYMERIZATIONOF PROPYLENE Ⅲ. THE INFLUENCE OF DIFFERENT KINDS OF -OR GROUP ON THE CATALYTIC FUNCTION

We have studied the catalytic systems, Ti(OE)_nCl_4-n, supported on MgCl₂-EB (EB stands for ethyl benzoate) for stereospeeific polymerization of propylene. In this paper, the influences of different kinds and number of -OR group on the catalytic function were reported. The result showed that all of these catalysts are in high activity for polymerization of propylene and high isotactic structure of polypropylene. The activity of n-C₅H₁₃OTiCl₃ is the highest among them. Because of the steric hindrance, the increase of the number of --OR group leads to decrease catalytic activity and reguarity, When alkoxyl groups were introduced in the titanium active species,the molecular weight of the polymer was decreased obviously.