Functionalized polyesters derived from glycerol: Selective polycondensation methods toward glycerol-based polyesters by different catalysts

Convergence of biodegradability and functionality is a major direction of new generation bio-based materials. Functionalized aliphatic polyesters based on glycerol are synthesized by solvent-free polycondensation directly. The aim is to prepare linear polyesters with pendant hydroxyl groups along the polymer backbone. The performance of the sustainable biocatalyst Novozyme-435 (an immobilized form of Candida antarctica lipase B) and the metal-based catalyst scandium trifluoromethanesulfonate (also known as scandium triflate) were compared with three organobase catalysts: 1,5,7-triazabicyclo[4,4,0]dec-5-ene, diphenyl hydrogen phosphate, and bis(1,1,2,2,3,3,4,4,4-nonafluoro-1-butanesulfonyl)imide. For the five catalytic systems, the efficiency and selectivity for the incorporation of glycerol were studied, mainly using H-1 NMR spectroscopies, whereas side reactions, such as different macromolecular architecture of different glyceride groups in polymers, were evaluated using C-13 NMR. Especially, the biocatalyst Novozyme-435 succeeded in incorporating glycerol in a selective way with a low reaction temperature, leading to close-to-linear polyesters. By using a renewable hydroxyl-reactive based on polyesters derived from glycerol, it provides a theoretical reference for the synthesis of functional bio-based materials. (c) 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48574.