Preparation of polymers with polycarbonate sequences and their depolymerization; an example of thermodynamic recycling

Initiators based on hydroxytelechelic polyethylene oxide, polytetrahydrofuran and polydimethylsiloxane were used for the anionic ring-opening polymerization of 2.2-dimethyltrimethylene carbonate (DTC). Under suitable conditions high yields of block copolymers of the AB and ABA types were obtained, depending on the initiator used. Ring-closing depolymerization of poly(2.2-dimethyltrimethylene carbonate) poly(DTC)] and of copolymers containing poly(DTC) blocks with catalysts based on potassium or tin results under suitable conditions in DTC.