Precise synthesis of structure-controlled poly (lactic acid)s by acid-base organocatalyst and their application to industrial materials

Abstract

A new acid-base organocatalyst inspired by enzyme has been developed focusing on the enzymatic active site of lipase-catalyzed ring-opening polymerization. Both solution polymerization and bulk polymerization are possible, and "precise poly (lactic acid)s" with a theoretical molecular weight calculated from the monomer/initiator ratio can be obtained quantitatively up to enough high degree of polymerization for industrial use. In addition, depending on the initiator, it is possible to design various polymers with controlled structures, including the introduction of linear and branched structures, modification of both terminal groups, and block copolymerization. In this paper, at first, the reaction mechanism of acidbase organocatalyst and the relationship between the primary structures and function of poly (lactic acid)s obtained by this precision synthesis method have been shown. Next, application to adhesives of poly (lactic acid)s with long-chain multibranched structures has been explained. Finally, a new try for networked poly (lactic acid)s with controlled distances of cross-linking will be discussed.