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

Autor(es)

Perin, Giovanni B. ; Felisberti, Maria, I

• Tipo de documento: Artigo Científico
• Fonte: MACROMOLECULES; v. 53, n. 18, p. 11-pg., 2020-09-22.

Resumo

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)

• Processo FAPESP: 18/01562-6 - Polímeros inspirados em fosfolipídeos: poliésteres anfifílicos com grupo dihidrogenofosfato pendente
• Beneficiário: Giovanni Bortoloni Perin
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 15/25406-5 - Organizando a matéria: colóides formados por associação de surfactantes, polímeros e nanopartículas
• Beneficiário: Watson Loh
• Modalidade de apoio: Auxílio à Pesquisa - Temático