Degradable branched and cross-linked polyesters from a bis(1,3-dioxolan-4-one) core

The control of macromolecular architecture is key to tailoring polymers, with cross-linked and branched topologies conferring useful bulk properties. However, conventional methods to produce topologically diverse polymers typically rely on fossil-fuel derived starting materials and non-degradable backbones. This work reports a facile approach to produce both cross-linked and branched polyesters, using a bio-derived bis(1,3-dioxolan-4-one) (bisDOX) core. Through the copolymerisation of bisDOX with readily available diols, we demonstrate the synthesis of cross-linked polyesters with diverse thermal properties and understand their structure-property relationships. Additionally, branched polyesters are synthesised via the introduction of a tri-functional alcohol monomer with branched structures characterised by detailed NMR spectroscopy. Model compound studies reveal the reactivity of bisDOX and identify preferential, but not exclusive, reactivity at primary vs. secondary hydroxyls. Moreover, multiple end-of-life fates are investigated, with both reprocessability and degradability of the cross-linked polyesters explored. This work offers insights into the synthesis of topologically diverse polyesters and highlights information that could inform the future design of more sustainable materials. Reaction of diols and triols with a bis(1,3-dioxolan-4-one) core derived from tartaric acid affords topologically diverse cross-linked and branched polyesters that are both reprocessable and hydrolytically degradable.