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.