先进催化剂及其用于乙烯/丙烯配位共聚的研究进展  

Progress in advanced catalyst and their use in ethylene/propylene copolymerization

作　　者：张树[1] 张志乾 吴一弦[1] Shu Zhang;Zhiqian Zhang;Yixian Wu(State Key Laboratory of Chemical Resource Engineering,Beijing University of Chemical Technology,Beijing 100029,China)

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,北京100029

出　　处：《科学通报》2018年第34期3530-3545,共16页Chinese Science Bulletin

基　　金：国家自然科学基金(21634002,21774006)资助.

摘　　要：乙烯-丙烯共聚物及乙烯-丙烯-少量二烯烃共聚物(简称乙丙橡胶)只能通过催化剂作用下烯烃配位共聚方法来合成,其微观结构、共聚组成、序列分布及拓扑结构等与催化剂密切相关.乙丙橡胶是世界上七大通用合成橡胶品种之一,具有优异的弹性、耐臭氧、耐热、耐候及耐老化性能等,应用广泛.本文分别论述了乙烯/丙烯配位共聚中所用催化剂的研究进展、催化特性及工业应用情况,主要包括齐格勒-纳塔催化剂、茂金属催化剂和非茂金属配合物催化剂,探讨主催化剂中金属的种类与价态、主催化剂中配体的结构、助催化剂、添加剂等因素对催化活性、共聚组成、分子量、分子量分布及序列分布等的影响规律.采用先进催化剂,可提高催化活性及丙烯插入率,调控共聚物的分子量及其分布,调控共聚物的序列分布与拓扑结构,设计合成高性能乙丙橡胶.Ethylene-propylene rubber (EPR)and ethylene-propylene-diene rubber (EPDM)have important market shares of the industry due to their excellent resistance toward heat,oxidation,weather,and other chemicals.EPR and EPDM have been synthesized by ethylene/propylene copolymerization and ethylene/propylene/nonconjugated diene copolymerization,respectively,employing Ziegler-Natta,metallocene and metal complex catalysts.Catalyst plays important roles in the copolymerization of ethylene and propylene.The progress of Ziegler-Natta,metallocene and metal complex catalysts and their use in ethylene/propylene copolymerization were reviewed.The characteristics and application in the industry of these advanced catalysts were introduced.The effects of metals and their valence in catalysts,chemical structure of ligands,cocatalysts and additives on the catalytic activity,composition,molecular weight,molecular weight distribution and sequence of the resulting ethylene-propylene copolymer were discussed. Vanadium based Ziegler-Natta catalyst is still promising in ethylene/propylene copolymerization.The open active site of vanadium catalyst results in random ethylene-propylene copolymers,which prevent the formation of long crystallized ethylene sequences.Meanwhile,the good solubility in alkanes and low cost of vanadium-based Ziegler-Natta catalyst are benefit for the application for the production of ethylene-propylene rubber in industry.About 70%of the commercial E/P copolymers are conducted by using vanadium based Ziegler-Natta catalysts.However,the unstable active centers brought low activity and the catalyst residues should be removed from the polymer product after deactivation.In order to improve the catalytic activity of vanadium-based Ziegler-Natta catalyst,the additives including electron donor and promoter are usually introduced to the catalytic system.The reactivity ratio of the monomer and the microstructure of the resulting ethylene-propylene copolymer could be adjusted by the additives. Metallocene catalyst,as a single-site

关 键 词：乙丙橡胶 催化剂 配位聚合 烯烃共聚 

分 类 号：O643.36[理学—物理化学] O631.5[理学—化学]