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

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

机构地区：[1]School of Materials Science and Engineering, PCFM Lab, GD HPPC Lab, Sun Yat-sen University

出　　处：《Chinese Journal of Polymer Science》2019年第10期959-965,I0003,共8页高分子科学（英文版）

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)

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 polyolefin.Semicrystalline polyolefins with high melting temperatures(Tm) were made from α-olefins through highly regioselective 2,1-insertion and precise chain-straightening.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 polyolefin.Semicrystalline polyolefins with high melting temperatures（Tm） were made from α-olefins through highly regioselective 2,1-insertion and precise chain-straightening.

关 键 词：Nickel catalyst Α-OLEFIN POLYMERIZATION Regioselectivity Chain WALKING 

分 类 号：O62[理学—有机化学]