Regulation of α-diimine nickel catalyzed olefin polymerization by remote site modifications

Abstract

The strategy of catalyst remote-site modification has the potential ability to modulate catalytic behaviour that was always ignored in the coordination-insertion olefin polymerization. Utilizing this strategy in this contribution, we designed a series of remote site-modified α-diimine nickel catalysts with different substitutes. These complexes were investigated in the chain-walking polymerization of ethylene and 1-octene. The investigation of these complexes was conducted in the chain-walking polymerization of ethylene and 1-octene. The remote site modified nickel catalyst in this work demonstrated higher catalytic activity and thermal stability compared to the classical counterpart without modification. Especially, complex Ni4 produced polyolefin with the largest molecular weight (up to 20.6 × 104 g mol−1). The introduction of the remote substitute could influence the steric hindrance and electronic effects, enabling to modulate the olefin polymerization process efficiently. The research of the remote-site modified catalyst designing provides another strategy in olefin polymerization and also may inspire more application in other metal-catalysis areas.