Regioselective Polymerizations of α-Olefins with an α-Diamine Nickel Catalyst

作     者：Heng Liao Jie Gao Liu Zhong Hai-Yang Gao Qing Wu 

作者机构：School of Materials Science and Engineering PCFM Lab GD HPPC Lab Sun Yat-sen University 

出 版 物：《Chinese Journal of Polymer Science》 (高分子科学（英文版）)

年 卷 期：2019年第37卷第10期

页      面：959-965,I0003页

核心收录：

学科分类：081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 070303[理学-有机化学] 0703[理学-化学] 

基　　金：financially supported by the National Natural Science Foundation of China (Nos. 21674130, 51873234) Natural Science Foundation of Guangdong Province (No. 2017A030310 349) Fundamental Research Funds for the Central Universities (No. 17lgjc02) PetroChina Innovation Foundation (No. 2017D-5007-0505) 

主　　题：Nickel catalyst α-Olefin Polymerization Regioselectivity Chain walking 

摘      要：Polymerizations of linear α-olefins(CnH2n, CH2=CH―R, R = Cn-2) catalyzed by early transition metals typically afford amorphous polymers with alkyl chains(Cn-2), while chain-straightening polymerizations of α-olefins with nickel-based catalysts produce semicrystalline polyolefins. Polymerizations of various α-olefins were carried out using an α-diamine nickel catalyst with a significantly distorted chelating ring. The influences of temperature, monomer concentration, and chain length of α-olefins on polyolefin microstructure were examined in detail. The α-diamine nickel catalyst realized highly regioselective 2,1-insertion of α-olefins regardless of reaction temperature and monomer concentration. Increased chain length of α-olefins led to the formation of more linear *** polyolefins with high melting temperatures(Tm) were made from α-olefins through highly regioselective 2,1-insertion and precise chain-straightening.