Enzymatic Synthesis of Poly(glycerol sebacate): Kinetics, Chain Growth, and Branching Behavior

Author(s)

Perin, Giovanni B. ; Felisberti, Maria, I

• Document type: Journal article
• Source: MACROMOLECULES; v. 53, n. 18, p. 11-pg., 2020-09-22.

Abstract

Immobilized Candida antarctica lipase B (CALB)-catalyzed polycondensation of glycerol and sebacic acid at mild reaction conditions resulted in branched poly(glycerol sebacate) (PGS). To understand how PGS chains grow and branch, the kinetics of the CALB-catalyzed polycondensation were studied. The influence of the reaction temperature, solvent, CALB amount, and sebacic acid/glycerol feed ratio on the poly(glycerol sebacate) (PGS) molecular weight, degree of branching, and glyceridic repetitive unit distribution was also investigated. PGS architecture changes from linear to branched with the progression of the reaction, and the branching results from the simultaneous CALB-catalyzed esterification and acyl migration. For reactions performed in acetone at the temperature range from 30 to 50 degrees C, the apparent rate constant increases from 0.7 to 1.5 h(-1), and the apparent energy of activation of 32 kJ mol(-1) was estimated. The higher mass average molecular weight (16 kDa) and degree of branching (41%) were achieved using the equimolar sebacic acid/glycerol feed ratio in acetone at 40 degrees C with a CALB amount of 13.6 wt % and in the presence of the molecular sieves. (AU)

• FAPESP's process: 18/01562-6 - Polymers inspired by phospholipids: polyesters with dihydrogen phosphate pendent group
• Grantee: Giovanni Bortoloni Perin
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• FAPESP's process: 15/25406-5 - Organizing matter: colloids formed by association of surfactants, polymers and nanoparticles
• Grantee: Watson Loh
• Support Opportunities: Research Projects - Thematic Grants