Epoxy Resin Recycling: Challenges, Technologies, and the Path to Sustainable Circularity

Epoxy resins are critical in engineering due to their superior mechanical, thermal, and chemical properties, yet their crosslinked structure poses major recycling challenges.This review presents a comprehensive synthesis of emerging strategies for epoxy resin sustainability, uniting advanced recycling methods, bio-based material innovations, and life cycle assessments (LCA) with patent and policy analyses.It critically evaluates chemical, thermal, mechanical, and hybrid recycling techniques, emphasising scalability, costeffectiveness, and environmental performance.Key developments include solvolysis-based depolymerisation, vitrimer chemistry, and ionic liquid-assisted degradation, enabling highpurity monomer recovery and fibre preservation.The integration of bio-based epoxiesderived from lignin, vanillin, and plant oils-is explored alongside dynamic covalent bonding systems to create fully reprocessable thermosets.LCA results indicate carbon footprint reductions of up to 39% for these alternatives, affirming their industrial potential in aerospace, automotive, and electronics.A thorough patent landscape analysis highlights a growing shift toward chemical recycling and circular resin design.This review bridges fundamental chemistry with applied innovation, identifying knowledge gaps, benchmarking current solutions, and outlining scalable pathways for implementation.By aligning technological advances with policy and market trends, it offers critical insights for accelerating the transition to circular, sustainable epoxy resin systems.