Patent ID: 9029497
Filing Date: 2015-05-12
Classification: B01J,C08G

Abstract:
1. A method of making polylactic acid through lactide polymerization, comprising: providing a carbon dioxide adduct of carbene; forming a reaction mixture comprising a lactide and the carbon dioxide adduct of carbene; adjusting a temperature of the reaction mixture to 50° C. to 180° C., wherein the carbon dioxide adduct of carbene has a structure represented by formula (I): wherein the dotted line together with the solid line parallel to the dotted line represent a single bond or a double bond; X X wherein R alkyl groups having 1 to 10 carbon atoms, alkyl groups having 1 to 10 carbon atoms and also having one or more substituents chosen from halogens, a hydroxyl group, a phenyl group, and a cyano group, cycloalkyl groups having 3 to 6 carbon atoms, a halogen atom, and an adamantane group; wherein R