Glucose-Derived Circular Thermoset Platform Breaks the Industrial Trilemma of Recyclable Structural Polymers.

Abstract

The long-standing trilemma of scalable green synthesis, industrial processing compatibility, and balanced performance-circularity represents the core barrier limiting real-world deployment of recyclable thermosets. Here, we report an exogenous catalyst- and solvent-free one-pot strategy with ∼100% atom economy to fabricate glucose-derived built-in dynamic covalent thermosets from three industrial bulk feedstocks: glucose, maleic anhydride, and pentaerythritol tetrakis(3-mercaptopropionate). The optimal formulation achieves an unprecedented balance between >130 d of room-temperature shelf life (no gelation) and 2-min gelation at 150°C, delivering engineering-grade tensile strength up to 113 MPa, 17.5 MPa steel lap shear strength, and drop-in compatibility with industrial vacuum-assisted resin infusion for large carbon fiber composite manufacturing. We demonstrate complete room-temperature closed-loop recycling: nondestructive recovery of high-value carbon fibers with full performance retention, and matrix degradation products (73.2%-83.1% isolated yield) upcyclable into high-performance epoxy curing agents. Thermal reprocessing provides an additional reuse pathway for manufacturing scrap. Our cradle-to-grave life cycle assessment confirms 81.4% lower CO₂-equivalent emissions than virgin bisphenol A epoxy carbon fiber composites. This work establishes a generalizable, industrially deployable paradigm for circular high-performance thermosets, resolving the long-standing trilemma impeding recyclable thermosets deployment.