Catalyzed Polymerization of Cyclic Esters and Cyclic Carbonates

摘要

The present invention relates to a process for the preparation of polyesters or polycarbonates comprising (i) the provision of cyclic esters or cyclic carbonates, (ii) polymerizing by ring-opening in the presence of a betaine based metal-free catalyst showing formula
€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ -X-R 1 -Y + (R 2 ) 3
wherein X is S, O or Se,
Y is N or P,
R 1 is linear or cyclic alkyl or aryl, and
R 2 is linear or cyclic alkyl.
and under polymerizing conditions in the presence of an alcohol or amine based initiator.