CATALYSTS AND METHODS FOR POLYMER SYNTHESIS

摘要

The present invention provides unimolecular metal complexes having increased activity in the copolymerization of carbon dioxide and epoxides. Also provided are methods of using such metal complexes in the synthesis of polymers. According to one aspect, the present invention provides metal complexes comprising an activating species with co-catalytic activity tethered to a multidentate ligand that is coordinated to the active metal center of the complex.

主权项

1. A method for the synthesis of aliphatic polycarbonates comprising the step of contacting an epoxide and carbon dioxide with a metal complex comprising a metal atom coordinated with a salen ligand, the salen ligand comprising two halves each half coordinated to the metal atom via an imine and an oxygen atom, wherein the metal complex is characterized in that one of the two halves of the salen ligand has two or more cationic activating moieties functional groups tethered to it and the other half has no tethered cationic activating groups.