Enzymatic polymerization of various biobased and biodegradable BHMTHF-based (co)polyesters

Abstract

2,5-Bishydroxymethyltetrahydrofuran (BHMTHF), also known as 2,5-tetrahydrofurandimethanol (THFDM), is a sugar-derived monomer containing a rigid alicyclic tetrahydrofuran structure. In this study, three series of BHMTHF-based (co)polyesters were enzymatically synthesized using various aliphatic comonomers and the furanic comonomers 2,5-bishydroxymethylfuran (BHMF) and 2,5-furandicarboxylic acid (FDCA). The length of the aliphatic comonomers had a significant effect on the T_g and complex viscosity. Similarly, a higher furan content, either BHMF or FDCA, in the copolyesters increased the T_g values and complex viscosities. Biodegradation experiments in activated sludge demonstrated that all aliphatic-BHMTHF-based polyesters were biodegradable, with rates ranging from 60 to 89% in 28 days. In addition, the furan-BHMTHF-based copolyesters also demonstrated a biodegradable behavior over time, without a significant influence of either the BHMF or FDCA content. Finally, the greenness of the enzymatic synthesis process was assessed based on atom economy (AE), reaction mass efficiency (RME), overall efficiency (OE), E-factor, and EcoScale. This work supports the tuneability of the thermal and rheological properties of BHMTHF-based (co)polyesters and reveals the biodegradability of these materials. This emphasizes that BHMTHF is a very promising biobased rigid monomer for the production of sustainable (co)polyesters.