Kaminsky catalyst

A Kaminsky catalyst is a catalytic system for alkene polymerization discovered in 1980. Kaminsky catalysts are based on metallocenes of group 4 transition metals with methylaluminoxane (MAO). These catalysts are a type of Ziegler-Natta catalyst, but they are homogeneous and show extremely high activity for polymerization of olefins such as ethylene and propylene. In addition, the use of chiral metallocenes that have bridged cyclopentadienyl rings has made possible highly stereoselective (or stereoregular) polymerization of α-olefins. For example, by using metallocene 1 for polymerization of propylene, atactic polypropylene is obtained, while C₂symmetric metallocene 2 and C_s symmetric metallocene 3 catalytic systems produce isotactic polymer and syndiotactic macromolecule, respectively.