Enzymatic synthesis of aromatic biobased polymers in green, low-boiling solvents

• Published in: Journal of biotechnology Vol. 396; pp. 1 - 9
• Main Authors: Salum, Thaís Fabiana Chan, Day, Daniel, Sherwood, James, Pellis, Alessandro, Farmer, Thomas James
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 10.10.2024
• Subjects: Biomass-derived monomers; Enzymatic polycondensation; Eucalyptol; Green solvents; Pyridinedicarboxylic acids; Sustainable polymers; Eucalyptol; Enzymatic polycondensation; Sustainable polymers; Pyridinedicarboxylic acids; Biomass-derived monomers; Green solvents; pyridinedicarboxylic acids; sustainable polymers; biomass-derived monomers; green solvents; eucalyptol; enzymatic polycondensation
• ISSN: 0168-1656; 1873-4863; 1873-4863
• DOI: 10.1016/j.jbiotec.2024.10.003

Given the urge to accelerate the substitution of petrol-derived solvents not only in more traditional fields like pharmaceuticals, personal care, or electronics but also in innovative research processes, this work focuses on the utilisation of four biobased solvents as media for the enzymatic synthesis of aliphatic-aromatic polyesters. As building blocks, the lignin-derived diethyl-2,4-pyridinedicarboxylate was selected as the potentially biobased, aromatic component while more classical diols such as 1,4-butanediol and 1,8-octanediol were used as the aliphatic portion. Results show that among the tested green solvents (cyclohexanone, phenetole, anisole and eucalyptol), the most suitable medium for lipase B from Candida antarctica-catalysed polycondensation reactions was eucalyptol that allowed reach monomer conversions >95 % and number average molecular weights up to 3500 g·mol−1. On the other hand, cyclohexanone led to the lowest monomer conversions (<80 %) and molecular weights (Mn<500 g·mol−1) confirming once again the unsuitability of ketone-containing solvents for enzymatic esterification and transesterification reactions. The lipase could be used up to three times, in eucalyptol as a solvent, without a significant decrease in monomer conversion or molecular weight. •Eucalyptol was the best solvent for enzymatic-catalysed polycondensation reactions.•Anisole, eucalyptol and phenetole were used as solvents for the enzymatic synthesis of polyesters.•Cyclohexanone was unsuitable as a solvent for enzymatic synthesis of polyesters.•The lipase could be used up to three times without a decrease in monomer conversion.