Reactor blending with early/late transition metal catalyst combinations in ethylene polymerization

摘要

Ethylene is polymerized by heterobimetallic combinations of early and late transition metal catalysts. Dual combinations of zirconocenes and cationic nickel and iron catalysts with multidentate nitrogen-donor ligands are described. Reactor blends of linear and branched ethylene homopolymers are obtained. With zirconocene / nickel complex catalyst combinations, addition of hydrogen selectively reduces the molecular weight of the linear polyethylene formed by the metallocene catalyst.