Beyond durability: the transformative journey of carbon fiber reinforced epoxy composites through advanced interfacial engineering, self-healing, and vitrimer-enabled recycling

Carbon fiber-reinforced epoxy (CFRE) composites have become indispensable in high-performance structural applications in aerospace and automotive sectors due to their high strength-to-weight ratio and robust environmental resistance. However, they have a few limitations, such as inherent susceptibility to damage, limited reparability, and a lack of effective recyclability at the end-of-life. These limitations prevent their sustainable adaptation, perpetuating a linear economy paradigm. This comprehensive and critical review delves into the cutting-edge advancements made to address the limitations of CFRE composites. We rigorously evaluate the synergistic integration of nanomaterials and advanced interfacial engineering strategies designed to address these issues. The diverse nanomaterials, such as carbon nanotubes (CNTs), graphene nanoplatelets (GNPs), graphene oxide (GO), nanosilica, and nanoclay, together with advanced interfacial modification techniques, significantly improve the properties of CFRE composites. Furthermore, this review delves into the evolving field of various self-healing mechanisms, such as- reversible Diels-Alder (DA) bonds, microencapsulated healing agents, vascularized networks, aimed at autonomously restoring structural integrity and extending operational lifespan Finally, we also look in to the formidable challenge of end-of-life by analyzing emerging recycling methodologies and highlighting the paradigm-shifting vitrimer concept, which enables the reprocessability of traditionally non-recyclable thermoset matrices. By providing an insightful, forward-looking analysis of these interconnected multifunctional enhancements and sustainable pathways, this review not only synthesizes the state-of-the-art but also delineates potential research directions. We aim to lay a robust roadmap for the establishment of truly enhanced, autonomously reparable, and environmentally friendly CFRE composites, promoting a circular economy.