EPOXIDE-CARBON DIOXIDE STEREOSELECTIVE ALTERNATING COPOLYMER

摘要

A process for producing a polycarbonate that realizes a high conversion ratio of propylene oxide raw material to polymer and allows control of the stereoregularity of polymer chain structure; and a catalyst compound for the process. There is disclosed a process for producing a polycarbonate copolymer through copolymerization of an epoxide compound as a monomer raw material with carbon dioxide in the presence of a planar tetracoordinated cobalt-Schiff base complex. The process is characterized in that the Schiff base ligand is N,N'-bis(2-hydroxybenzylidene)ethylenediamine or N,N'-bis(2-hydroxybenzylidene)phenylenediamine or a derivative therefrom and that a methyl substituted with an asymmetric carbon atom or an amino group with asymmetric axis is introduced in the 3-position and/or 3'-position of the benzene ring derived from salicyl. Further, there is disclosed a catalyst compound of cobalt-Schiff base complex characterized in that a methyl substituted with an asymmetric carbon atom or an amino group with asymmetric axis is introduced in the 3-position and/or 3'-position of the salicyl.