用负载型钛系催化剂制备的乙丙共聚物链结构的影响因素  

Influence of polymerization conditions on the chain structure of ethylene-propylene copolymer prepared by MgCl_2/TiCl_4 catalyst

作　　者：肖娴 董奇[1] 傅智盛[1] 范志强[1] 

机构地区：[1]高分子合成与功能构造教育部重点实验室,浙江大学高分子科学与工程学系,浙江省杭州市310027

出　　处：《合成树脂及塑料》2013年第1期1-5,共5页China Synthetic Resin and Plastics

基　　金：国家重点基础研究发展规划项目(973计划)(2011CB606001);化学工程联合国家重点实验室开放课题资助(SKL-ChE-10D03)

摘　　要：以负载型钛系催化剂为主催化剂,采用常压淤浆聚合工艺进行乙烯与丙烯共聚合,考察聚合条件对共聚合行为和产物结构的影响。以三乙基铝/三异丁基铝(TiBA)混合物为助催化剂时,随着TiBA用量增加,共聚物中聚丙烯(PP)链段越来越长,且长PP链段数量越来越多,而长聚乙烯(PE)链段数量逐渐减少;空间位阻大的外给电子体虽然可以提高PP的规整度,但不利于形成长PP链段;适当降低聚合温度更有利于形成长PP链段;产物中嵌段共聚物的含量随TiBA用量的增加而提高。所以,改变助催化剂的组成、使用不同的外给电子体或调节聚合温度都可以调控乙烯-丙烯共聚物的链结构及其分布。Copolymerization of ethylene and propylene was carried out in slurry by using TiCl4/MgCl2 as catalyst.The influence of polymerization conditions on the copolymerization behavior and the chain structure of ethylene-propylene copolymers were studied.Using triethylaluminum/triisobutylaluminum（TiBA） mixture as cocatalyst,the length and amount of long polypropylene（PP）block increased,however,the amount of long polyethylene（PE）block decreased with the augmentation of TiBA dosage.External donor with higher steric hindrance could improve the isotacticity of PP,but it was harmful for the formation of long PP block.Properly decreasing the polymerization temperature was beneficial to the formation of long PP block.The amount of long PP block increased with the augmentation of TiBA.Therefore,changing the composition of the cocatalyst,using different external donors or adjusting the polymerization temperature could regulate the chain structure and its distribution of ethylene-propylene copolymer.

关 键 词：乙烯-丙烯共聚物 负载型钛系催化剂 链结构 聚合条件 

分 类 号：TQ325.14[化学工程—合成树脂塑料工业] O632.12[理学—高分子化学]