Highly Robust Nickel Catalysts Containing Anilinonaphthoquinone Ligand for Copolymerization of Ethylene and Polar Monomers

Copolymerizations of ethylene with polar monomers such as 5-hexene-1-yl acetate and allyl acetate are explored using nickel complexes bearing a class of anilino­naphthoquinone ligands. High tolerability of this complex toward polar comonomer is achieved by the installation of sterically bulky substituent on the aniline ligand. Moreover, the heterogenization of the nickel complexes using silica-supported modified methylaluminoxane enhances the copolymerization performances. The catalyst is highly active and thermally stabile to give semicrystalline ester-functionalized high molecular weight polyethylenes.