Macrocyclic Binuclearα-Diimine Nickel Catalysts for Ethylene Polymerization  

作　　者：YANG Jingshuang ZHANG Yuxing JIAN Zhongbao 

机构地区：[1]State Key Laboratory of Polymer Physics and Chemistry,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022,P.R.China [2]School of Applied Chemistry and Engineering,University of Science and Technology of China,Hefei 230026,P.R.China

出　　处：《Chemical Research in Chinese Universities》2023年第5期797-802,共6页高等学校化学研究（英文版）

基　　金：This work was supported by the National Natural Science Foundation of China(No.22122110);the Science and Technology Department Program of Jilin Province,China(No.20230101347JC).

摘　　要：Polyolefins are globally important plastics.Molecular weight and molecular weight distribution are two key parameters for determining the properties of polyolefin materials.In this contribution,we develop a strategy for combining the macrocyclic framework and the binuclear effect into the benchmarkα-diimine late transition metal catalysts,and thus macrocyclic binuclearα-diimine nickel catalysts(Ni_(2)-Me and Ni_(2)-iPr)are prepared.Compared to the classical Brookhart's acyclic mononuclearα-diimine nickel analogues(Ni_(1)-Me and Ni_(1)-iPr),these nickel catalysts exhibit enhanced thermostability(up to 110℃)and produce polyethylenes with higher molecular weights(up to 7 times)and lower branching densities(as low as 9 branches/1000C)in methylaluminoxane(MAO)activated ethylene polymerization.This translates into the ability of the catalyst to afford more linear high molecular weight polyethylenes.In particular,bimodal polyethylenes with broad molecular weight distributions(Mw/Mn=8.08-14.66)are generated by the sole catalyst.This work affords diverse polyethylenes.

关 键 词：POLYOLEFIN Nickel catalyst Diimine ligand Macrocyclic binuclear strategy Bimodal polyethylene 

分 类 号：O631.5[理学—高分子化学]