Bio-based vitrimers: chemistry, performance and applications

Despite being widely used in industrial applications, thermoset polymers arguably present a major challenge to modern society due to the near impossibility of their end-of-life recycling and reprocessing. Furthermore, there are difficulties in finding bio-based alternatives to the fossil-based building blocks used for their production that can deliver comparable mechanical performance. These limitations have driven growing interest in vitrimers, associative covalent adaptable networks capable of being recycled, welded and reprocessed without changes in cross-linking density through dynamic covalent exchange. Vitrimers provide a promising strategy to address both the recyclability of thermosets and the need for more sustainable materials. The use of bio-based chemicals in vitrimer production can further help reduce the environmental impact and toxicity, supporting the transition to circular polymer systems. This review summarizes recent advances in bio-based vitrimer systems, with particular emphasis on renewable feedstocks such as carbohydrates, lignin-derived aromatics, and vegetable oils, and their translation into functional materials. Rather than focusing solely on exchange chemistry concepts, the manuscript highlights the emerging applications of newly developed bio-based vitrimers in composites, packaging, additive manufacturing, adhesives, electronics, and foams. By organizing recent literature according to feedstock families and application domains, this work provides an updated, application-oriented perspective on the development of sustainable vitrimer technologies. Overall, bio-based vitrimers represent a promising platform for the development of next-generation recyclable thermosets within a circular and sustainable polymer framework.