一段反应法制备宽/双峰聚乙烯催化剂的研究进展  

Advance in Catalysts for Broad or Bimodal Molecular Weight Distribution Polyethylene

作　　者：汪红丽[1] 孔媛[1] 义建军 张明革 黄启谷[1] 赵杨锋[1] 马利福[1] 李俊拢[1] 邓坤学[1] 杨万泰[1] 

机构地区：[1]北京化工大学化工资源有效利用国家重点实验室,材料科学与工程学院现代大分子工程系,北京100029 [2]中国石油石油化工研究院合成树脂重点实验室,北京100083

出　　处：《高分子通报》2009年第9期19-31,共13页Polymer Bulletin

基　　金：中石油风险基金(GrandNo.07-06D-01-04-04-06);国家自然科学基金(20574003);北京市教委重点学科共建项目(XK100100540;XK100100640);IRT0706

摘　　要：阐述了采用一段反应法制备宽/双峰聚乙烯催化剂的研究开发进展,并根据催化剂的组成和结构,将催化体系归纳为复合催化剂和单组分催化剂。复合催化剂包括茂金属/Ziegler-Natta复合催化剂、不同茂金属复合催化剂、铬系/Ziegler-Natta复合催化剂、茂金属/后过渡金属复合催化剂、非茂单活性中心/茂金属复合催化剂、非茂单活性中心/Ziegler-Natta复合催化剂和不同后过渡金属复合催化剂。复合催化剂中多活性组分具有不同的链增长、链转移、链终止速率常数,从而在聚合反应中得到不同相对分子质量的聚合物,导致其相对分子质量分布加宽,因而复合催化剂可用于一段反应法制备宽/双峰聚乙烯。单组分催化剂包括单核茂金属催化剂、多核茂金属催化剂、后过渡金属催化剂及其它单组分催化剂。单组分催化剂可用于一段反应法制备宽/双峰聚乙烯,其催化机理是中心金属原子与主配体、辅配体、助催化剂、其它添加剂及载体形成了多种活性中心。The development in catalyst for broad or bimodal molecular weight distribution polyethylene prepared with the process of single-reactor was described. According to the composition and structure of the catalyst, the catalytic systems were classified as multi-component composite catalyst and mono-component catalyst. The multi- component composite catalysts were divided into metallocene/Ziegler-Natta composite catalyst, different metallocene composite catalyst, chromium based/Ziegler-Natta composite catalyst, metallocene/late transition metal composite catalyst, non-metallocene single site/metallocene composite catalyst, non-metallocene single site/Ziegler-Natta composite catalyst and different late transition metal composite catalyst. The multi-composite catalyst acted as individual active species, which had different kinetic responses, such as different propagation, termination, and transfer rate constants, and as a result, produced a blend of polymeric chains with two or more predominant molecular masses in ethylene polymerization via the process of single-reactor. The mono-component catalysts involved mononuclear metallocene catalyst, multinuclear metallocene catalyst and late transition metal catalyst and other mono- component catalyst. The mono-catalyst which was able to come into being various catalytic active centers could produce polyethylene with broad or bimodal molecular weight distribution in a single-reactor. To form different active species of the mono-component catalyst was probably resulted from that the catalyst was immobilized on different chemical or physical environmental supports and the center metal of the catalyst was coordinated or reacted with ligand, ancillary ligand cocatalyst as well as additive.

关 键 词：宽/双峰聚乙烯 复合催化剂 单组分催化剂 一段反应法 

分 类 号：TQ325.12[化学工程—合成树脂塑料工业] TQ325.1