Recyclable, repairable and malleable bio-based epoxy vitrimers: overview and future prospects

The extensively used petroleum-based epoxy thermosets suffer from difficulty in recycling (reprocessing, self-healing, or welding) and biodegradation due to their permanent cross-linking network, which not only causes massive consumption of petroleum resources and shortened lifespan of epoxy ther-mosets, but also leads to serious environmental burden after discarding. Bio-based epoxy vitrimers with reversible dynamic covalent networks are competitive alternatives, which offer the advantages of robustness like thermosets and closed-loop recycling similar to thermoplastic, and thus agree well with the idea of carbon neutrality and sustainable development. Here, we reviewed the progress in the design and properties of bio-based epoxy vitrimers with different dynamic bonds and diverse biomass feedstock in the past two years, and also highlighted the major challenges and future prospects.