Renewable hydroxymethylfurfural epoxide and cyclic anhydride copolymerization: a green route to functional biobased polyesters

Abstract

The copolymerization of epoxides and cyclic anhydrides is a promising route for synthesizing polyesters with potential degradability and biocompatibility. In this study, a bio-based epoxy monomer derived from 5-hydroxymethylfurfural (5-HMF) copolymerized with cyclic anhydrides introduces aldehyde functionalities directly into the polyester backbone using a binary Cr(salen)Cl (1)/PPNCl catalytic system. The copolymerization with a broad range of renewable cyclic anhydrides and the use of propylene carbonate as a solvent make this process greener. Also, we highlighted the orthogonal post-polymerization modification (PPM) capabilities with poly(CFGE-alt-(exo-NA)) exploiting both aldehyde and alkene groups, demonstrating selective and independent aldehyde-to-imine and thiol-ene transformations in a one-pot dual PPM reaction. This methodology presents a sustainable pathway for bio-based polyester synthesis, enabling the tuning of material properties across diverse applications through a post-polymerization modification (PPM) approach.