Late-transition Metal Complex Pre-catalysts in Ethylene Polymerization

摘要

One crucial problem of late-transition metal complex pre-catalysts is the deactivation of catalytic species occurred at elevated temperatures,fortunately,that is likely solvable through tuning the ligands with steric and electronic influences of substituents.1 Regarding to catalytic system of the iron pre-catalysts,the resultant polyethylenes would be highly linear polymers such as high-density or waxes.2 On contrary,nickel pre-catalysts produced highly branched polyethylenes.3 The catalytic activities of complex pre-catalysts and the properties of resultant polyethylenes could be tunable through fine-tuning ligands with different substituents.Therefore the promising catalytic systems would be challengeable and applicable,and the new polyethylenes would be used as the advanced or high performance polymers.