Metallocenes

Abstract

Ever since their discovery by Sinn and Kaminsky in 1979, the family of high activity homogeneous olefin polymerization catalysts known as metallocenes has been the subject of intense research and commercial development. While a structurally diverse group, metallocene catalysts are generally considered to have a few common features: a highly electrophilic, early transition metal or rare‐earth atom as the point of polymer chain attachment; a π‐bound cyclopentadienyl ring or isoelectronic analogue attached to this atom; and characteristically narrow distributions of polymer molecular weight and short‐chain branching. While polymerization of ethylene and propylene is reviewed in some detail, the nonpolymerization catalysis and (co)polymerization of functional monomers is also surveyed. The current commercial status of metallocene technology is also briefly discussed.