Naphthyl-α-diimine nickel complexes with systematically varied ligand sterics, activated by modified methylaluminoxane（MMAO）, were tested in the polymerization of higher α-olefin（1-hexene, 1-decene and 1-hexadec...Naphthyl-α-diimine nickel complexes with systematically varied ligand sterics, activated by modified methylaluminoxane（MMAO）, were tested in the polymerization of higher α-olefin（1-hexene, 1-decene and 1-hexadecene） under suitable conditions. The polymerization results indicated the possibility of precise microstructure control, depending on catalyst structure, polymerization temperature, monomer concentration and types of monomers, which in turn strongly affects the resultant polymer properties. Naphthyl-α-diimine nickel complex bearing chiral bulky sec-phenethyl groups in the o-naphthyl position showed good catalytic activity, and resulted in branched polymers（42-88/1000 C） with high molecular weights（Mn：（4.3-15.2） × 10^4 g·mol^-1） and narrow molecular weight distribution（Mw/Mn = 1.13-1.29, RT）, which suggested a living polymerization. The increasing steric hindrance of catalyst leads to enhance insertion for 2,1-insertion of α-olefin and the chain-walking reaction.展开更多
Two novel Fe(Ⅱ) diimine complexes have been synthesized. In combination with MAO, they generate active catalytic systems that oligomerize ethylene with both high catalytic activity and high selectivity for a-olefins....Two novel Fe(Ⅱ) diimine complexes have been synthesized. In combination with MAO, they generate active catalytic systems that oligomerize ethylene with both high catalytic activity and high selectivity for a-olefins. The effects of substituents on the aryl ring, reaction temperatures and molar ratios of Al/Fe on catalytic activity and product distribution are studied.展开更多
基金financially supported by the Fundamental Research Funds for the Central Universities (WK2060200025)Advanced Catalysis and Green Manufacturing Collaborative Innovation Center (ACGM2016-06-01)Yixing Taodu Ying Cai Program
文摘Naphthyl-α-diimine nickel complexes with systematically varied ligand sterics, activated by modified methylaluminoxane（MMAO）, were tested in the polymerization of higher α-olefin（1-hexene, 1-decene and 1-hexadecene） under suitable conditions. The polymerization results indicated the possibility of precise microstructure control, depending on catalyst structure, polymerization temperature, monomer concentration and types of monomers, which in turn strongly affects the resultant polymer properties. Naphthyl-α-diimine nickel complex bearing chiral bulky sec-phenethyl groups in the o-naphthyl position showed good catalytic activity, and resulted in branched polymers（42-88/1000 C） with high molecular weights（Mn：（4.3-15.2） × 10^4 g·mol^-1） and narrow molecular weight distribution（Mw/Mn = 1.13-1.29, RT）, which suggested a living polymerization. The increasing steric hindrance of catalyst leads to enhance insertion for 2,1-insertion of α-olefin and the chain-walking reaction.
基金This work was supported by the Special Funds for the Major State Basic Research Projects (Grant No. G1999064800)the National Natural Science Foundation of China (Grant No. 29734141) the State Key Laboratory of Engineering Plastics (Grant No. 0062).
文摘Two novel Fe(Ⅱ) diimine complexes have been synthesized. In combination with MAO, they generate active catalytic systems that oligomerize ethylene with both high catalytic activity and high selectivity for a-olefins. The effects of substituents on the aryl ring, reaction temperatures and molar ratios of Al/Fe on catalytic activity and product distribution are studied.
