Lipase-Catalyzed Ring-Opening Polymerization of Lactones in the Presence of Aliphatic Polyesters to Ester Copolymers

Abstract

Ring‐opening polymerization of macrolides in the presence of aliphatic polyesters has been performed using Pseudomonas lipase as catalyst to produce ester copolymers with molecular weights of several thousands. The polymerization behavior was monitored by SEC and NMR. 13C NMR analysis showed that the resulting polymer was not a mixture of the starting polyester and the polymer from the macrolide, but a random copolymer consisting of both units. These data indicate that the lipase catalyzed the polymerization of the macrolide as well as the intermolecular transesterification of the starting and resulting polymers. The random copolymer was found to be highly crystalline by DSC and WAXD measurement. The present specific catalysis of the lipase was applied to the synthesis of ester copolymers by transesterification between two different polyesters.

Enzyme-Catalyzed Synthesis and Chemical Recycling of Polyesters

“…The lipase catalyzed the polymerization of the macrolide as well as the intermolecular transesterification of the starting and resulting polymers. [110] Lactones also copolymerized with divinyl esters and glycols by lipase to produce the copolyester, not a mixture of homopolymers. Two difScheme 23.…”

Lipase-Catalyzed Transesterification of Polyesters to Ester Copolymers

“…In using 5 mL of toluene, a similar tendency was observed in the SEC traces and the molecular weight of the copolymer obtained by the reaction for 168 h was 1.1 6 10 4 . In case of the lipase PF-catalyzed ring-opening polymerization of PDL in the presence of PCL in diisopropyl ether, [26] the hydrolytic degradation of PCL mainly took place at the initial reaction stage to decrease the molecular weight, and afterwards, the molecular weight gradually increased. On the other hand, a significant decrease of the molecular weight was not found at the initial stage of the present transesterification.…”

“…[25,26] Lipase PF also afforded the ester copolymer by the polymerization of PDL in the presence of poly(1,4-butylene adipate) (PBA). Furthermore, we were the first to demonstrate that the intermolecular transesterification between two different polyesters, PCL and poly(15-pentadecanolide) (PPDL), occurred via lipase PF catalysis to give the ester copolymer.…”

“…Furthermore, we were the first to demonstrate that the intermolecular transesterification between two different polyesters, PCL and poly(15-pentadecanolide) (PPDL), occurred via lipase PF catalysis to give the ester copolymer. [25,26] It was reported that lipase CA also showed high catalytic activity toward the transesterification of polyesters; ester copolymers were obtained by the lipase CA-catalyzed ring-opening copolymerization of CL with PDL [27] and transesterification between PCL and PPDL. [28] This study deals with the transesterification between PCL and poly(a,x-alkylene dicarboxylate)s using lipase CA catalyst (Scheme 1).…”

Biomacromolecules and Bio‐Related Macromolecules

“…[169] 6-Membered cyclic depsipeptides were polymerized by lipase catalyst, yielding biodegradable poly(ester amide)s. [170,171] Random ester copolymers were synthesized by the lipase-catalyzed polymerization of macrolides in the presence of poly(e-CL), in which intermolecular transesterifications of the polyesters took place frequently (Scheme 38). [172] Furthermore, this specific catalysis of lipase was applied to the synthesis of ester copolymer by transesterification between two different polyesters. [173] Under appropriate reaction conditions, the random copolymer from poly(e-CL) and poly(1,4-butylene adipate) was obtained by using lipase CA as a catalyst.…”