稀释剂对聚丙烯球形齐格勒-纳塔催化剂性能的影响

采用液相本体聚合法考察了异构脱蜡基础油与进口白油对氯化镁载体型高效球形齐格勒-纳塔催化剂催化丙烯聚合性能的影响,并用蒸馏法、密度计法和黏度指数计算法等分析了两种油的组成和基本物性,同时利用SEM和GPC表征了催化剂和聚合物。结果表明,与进口白油相比,异构脱蜡基础油的基本组成与进口白油接近;采用异构脱蜡基础油配制催化剂在技术路线上可行,经济上优于进口白油;异构脱蜡基础油对催化剂活性,以及聚丙烯的堆积密度、熔体流动速率和等规指数影响较小。

Effect of diluent on the properties of spherical Ziegler-Natta catalyst for propylene polymerization

Liquid phase bulk polymerization of propylene in the presence of a high efficiency spherical Ziegler-Natta catalyst with magnesium chloride compound as the carrier was studied.The effects of isomerization dewaxed base oil and imported white oil on the performance of the catalyst for propylene bulk polymerization were investigated in a 2 L reactor.The composition and the basic physical properties of isomerization dewaxed base oil and imported white oil were analyzed by distillation method,densimeter method and calculation method of viscosity index.The catalyst and the polymer were characterized by SEM and GPC.The results indicated that the composition of isomerization dewaxed base oil was basically close to that of imported white oil.Compared with the technology of imported white oil with catalyst,the technology of isomerization dewaxed base oil with catalyst was feasible,which was superior to that of white oil with catalyst in economy.Moreover,isomerization dewaxed base oil had little effect on the activity of the catalyst, bulk density of polypropylene,fusant flow rate and isotactic index.