Alternate Transition Metal Complex Based Diene Polymerization

Abstract

In the last decade, there has been a tremendous increase in the number of reports on transition metal complex-mediated butadiene homo- and copolymerization. While typical classical titanium, nickel, cobalt, and neodymium based catalysts have been almost exclusively applied to the production of high cis-1,4-polybutadiene, alternative catalyst systems are currently being developed which enable tuning of the polybutadiene microstructure and permit defined changes in polymer properties such as molecular weight distribution and changes in the polymer glass temperature. Besides new products such as high trans-1,4-polybutadiene or a polymer containing a defined amount of 1,2-polybutadiene, there are butadiene copolymers with different amounts of styrene, isoprene, or ethylene. These new materials should lead to new applications especially in the area of tires, high impact polystyrene (HIPS), and ABS. This review elucidates the new developments in the area of transition metal complex-based butadiene homo- and copolymerization focusing mainly on the transition metal catalyst, the polymerization process and the resulting polymers. Mechanistic details are discussed briefly and wherever useful for the understanding of the polymerization reaction.

Keywords:

• Polybutadiene
• Polymerization
• Butadiene
• Diene
• Copolymer
• Catalyst
• Rubber
• Synthetic rubber

Acknowledgment

The authors thank The Dow Chemical Company for support.