ABSTRACT Carbon‐fiber reinforced polymer (CFRP) composites are central to lightweight wind‐energy infrastructure but suffer from poor end‐of‐life circularity due to permanent epoxy thermoset matrices. Here we present a life‐cycle‐integrated molecular design strategy for circular epoxy resins based on a hindered phenylene biacetal architecture, overcoming the longstanding industrial trade‐offs between scalable synthesis, processability, high in‐service performance, chemical recyclability, and long‐term stability. The resins are prepared through one‐pot scalable synthesis (≥200 g), producing liquid monomers compatible with vacuum‐assisted resin infusion molding (VARI) with processing windows exceeding 60 min at 55°C. The resulting networks exhibit strong thermal–mechanical properties ( T g = 119°C–136°C, tensile strength ≥72 MPa) and significantly improved impact resistance (+83% vs. commercial bisphenol A epoxy), together with excellent durability, including negligible creep at 180°C and stable properties after prolonged hygrothermal aging (60°C/90% RH, 32 days). Dormant dynamic acetal linkages enable weak‐acid‐triggered deconstruction at room temperature, allowing 100% nondestructive carbon‐fiber recovery and >80% recovery of high‐purity monomeric precursors. Artificial‐intelligence‐assisted life‐cycle assessment indicates a 45%–56% reduction in cradle‐to‐grave CO 2 emissions compared with conventional CFRP disposal, with a total resource reutilization/upcycling rate exceeding 92%. This platform provides a practical pathway toward circular structural composites for net‐zero infrastructure.
Du et al. (Tue,) studied this question.