Enzymatic Synthesis of Renewable 2,5- Bis(hydroxymethyl)furan-Based Polyesters

2,5-Bis(hydroxymethyl)furan (BHMF) is a highly valuable biobased rigid diol resembling aromatic monomers in polyester synthesis. In this work, BHMF is enzymatically polymerized with various diacid ethyl esters by Candida antarctica lipase b (CALB) via a two-stage, three-step method. A series of novel biobased furan polyesters are successfully produced, with number average molecular weights (  ) of around 2000 g/mol. 1H-NMR and MALDI-ToF MS analysis indicate that etherification side reactions occur during the enzymatic polymerization, which lead to the formation of low molecular weight products. Moreover, the chemical structures, microstructures and end groups, and crystalline and thermal properties of the synthetic BHMF-based polyesters are extensively investigated. Furthermore, the effects of the number of the methylene units in the dicarboxylic segments on the physical properties of the obtained furan polyesters are discussed. This chapter was published in: Biomacromolecules 2014, 15, (7), 2482-2493.