A circular carbon fiber composite architecture enabled by synergistic multi-dynamic networks

The pervasive use of carbon fiber-reinforced epoxy (CFRE) laminates in aerospace and marine engineering is hindered by the permanent nature of conventional thermoset matrices, which precludes self-healing and end-of-life circularity. Furthermore, suboptimal interfacial bonding between the fiber and matrix frequently compromises structural performance. Here, we report a high-performance, fully circular CFRE architecture enabled by a dual-dynamic vitrimer epoxy (VE) matrix comprising associative disulfide and silyl ether covalent adaptable networks (CANs) reinforced with hydroxyl-functionalized graphene oxide (hGO). To bridge the interfacial gap, the carbon fiber (CF) surface was functionalized with a dissociative Diels-Alder (DA) adduct, creating a responsive covalent interface. This synergistic engineering resulted in a 53% increase in flexural strength (FS) and a 47% enhancement in interlaminar shear strength (ILSS) compared to conventional CFRE. Post-impact self-healing efficiency reached 64%, while the integrated functional network enabled high-efficiency EMI shielding (-46 dB) and rapid de-icing (47 s). Leveraging our patented SaLSO™ platform, we demonstrated damage-free, closed-loop recycling of both the matrix and the reinforcement. The recovered vitrimer epoxy (rVE) recovered carbon fiber (rCF) and the combination of both recovered carbon fiber reinforced vitrimer epoxy (rCFRVE) laminates were successfully upcycled into new laminates, retaining 92%, 96% and 85% of the virgin ILSS, respectively. This approach provides a robust framework for transitioning high-performance structural composites into the circular economy.