Horizontally and Vertically Concerted Steric Strategy inα-Diimine Nickel Promoted Ethylene(Co)Polymerization

作     者：Xiaoqiang Hu Yixin Zhang Baixiang Li Zhongbao Jian Xiaoqiang Hu;Yixin Zhang;Baixiang Li;Zhongbao Jian

作者机构：State Key Laboratory of Polymer Physics and ChemistryChangchun Institute of Applied ChemistryChinese Academy of SciencesRenmin Street 5625ChangchunJilin130022 China University of Science and Technology of ChinaHefeiAnhui230026 China 

出 版 物：《Chinese Journal of Chemistry》 (中国化学（英文版）)

年 卷 期：2021年第39卷第10期

页      面：2829-2836页

核心收录：

学科分类：081704[工学-应用化学] 07[理学] 070304[理学-物理化学(含∶化学物理)] 08[工学] 0817[工学-化学工程与技术] 0703[理学-化学] 

基　　金：support from the National Natural Science Foundation of China(Nos.21871250 for Z.Jian,22001244 for Y.Zhang) the Jilin Provincial Science and Technology Department Program(No.20200801009GH) 

主　　题：Olefin polymerization Steric effect Homogeneous catalysis UHMWPE Nickel 

摘      要：Main observation and conclusion Steric bulk plays a significantly paramount role in late transition metal promoted olefin(co)polymerization in terms of polymer molecular weight and catalyst thermal *** sterically encumbered nickel and palladium catalysts have been developed,but they are usually *** this contribution,from a bi-directional side the distinctive horizontally and vertically concerted steric strategy was well-developed and applied toα-diimine nickel *** ethylene polymerization,the increase of vertically steric bulk(H,Ph,Biph)led to an enhanced polymer molecular weight,a slightly ascended branching density;likewise increasing horizontally steric bulk(Ph,Nap,Ant)further resulted in the increase of polymer molecular weight and branching *** a result,in sharp contrast to Ni1(H)without steric bulk,Ni5(Ant)with horizontally and vertically concerted steric bulk was thermally stable,showed very high activities at a level of 107 g·mol–1·h^(–1),and produced polyethylenes with the highest molecular weight of 518.8×10^(4)g·mol^(-1)and the broader range of branching density from 2.4/1000C to 27.8/*** the copolymerization of ethylene with methyl 10-undecenoate,Ni5(Ant)also provided the highest copolymer molecular weight but gave the lowest incorporation of *** work sheds light on the steric effect on olefin(co)polymerization.