Coordination polymerization

Coordination polymerisation is a form of polymerization that is catalyzed by transition metal salts and complexes.

[1][2] Coordination polymerization started in the 1950s with heterogeneous Ziegler–Natta catalysts based on titanium tetrachloride and organoaluminium co-catalysts.

The mixing of TiCl4 with trialkylaluminium complexes produces Ti(III)-containing solids that catalyze the polymerization of ethene and propene.

[7] Kaminsky catalysts are based on metallocenes of group 4 metals (Ti, Zr, Hf) activated with methylaluminoxane (MAO).

The process entails coordination and often oxidative addition of Si-H centers to metal complexes.