Stereospecific Olefin Polymerization with Chiral Metallocene Catalysts

TLDR

Metallocene-based catalysts for α‑olefin polymerization offer a homogeneous alternative to Ziegler–Natta systems, enabling precise control over polymer chain growth and stereoregularity while opening avenues for new materials. Their defined coordination environment allows direct correlation between metallocene structure and polymer attributes such as molecular weight, stereochemistry, crystallization, and mechanical properties. These catalysts achieve efficient control of regio‑ and stereoregularity, molecular weight distribution, and comonomer incorporation, and enable homo‑ and copolymerization of cyclic olefins, dienes, and functionalized polyolefins, thereby broadening the scope of viable polyolefin materials. Corrigendum available at DOI 10.1002/anie.199513681.

Abstract

Abstract Current studies on novel, metallocenebased catalysts for the polymerization of α‐olefins have far‐reaching implications for the development of new materials as well as for the understanding of basic reaction mechanisms responsible for the growth of a polymer chain at a catalyst center and the control of its stereoregularity. In contrast to heterogeneous Ziegler–Natta catalysts, polymerization by a homogeneous, metallocene‐based catalyst occurs principally at a single type of metal center with a defined coordination environment. This makes it possible to correlate metallocene structures with polymer properties such as molecular weight, stereochemical microstructure, crystallization behavior, and mechanical properties. Homogeneous catalyst systems now afford efficient control of regio‐ and stereoregularities, molecular weights and molecular weight distributions, and comonomer incorporation. By providing a means for the homo‐ and copolymerization of cyclic olefins, the cyclopolymerization of dienes, and access even to functionalized polyolefins, these catalysts greatly expand the range and versatility of technically feasible types of polyolefin materials. For corrigendum see DOI: 10.1002/anie.199513681