Synergistic Supramolecular Bonding Enables Self‐Reinforcing and Chemically Recyclable Sustainable Materials

Developing polymer materials that break the long-standing trade-off between long-term durability and efficient chemical recyclability remains a fundamental challenge. We report an environmentally self-reinforcing and easily recyclable unprecedented biomass-derived supramolecular polyester that circumvents this limitation through the synergistic integration of dynamic hydrogen bonds and halogen-bond-assisted depolymerization. Amide-mediated hydrogen-bond networks undergo environment-activated supramolecular rearrangement under hygrothermal, ultraviolet, and electrical aging conditions, promoting chain realignment, recrystallization, and network densification. As a result, the material exhibits self-reinforcing behavior, achieving an ultrahigh tensile strength of 138.4 MPa (61% increase) and a UV-shielding efficiency of 98% (36% increase) while maintaining excellent electrical insulation. Simultaneously, halogen-bond interactions enhance solvent penetration and facilitate ester activation, enabling rapid depolymerization in dichloromethane at ambient temperature. Monomers are recovered with >99% purity and >90% yield for closed-loop repolymerization, while also enabling molecular upcycling into supramolecular adhesives exhibiting exceptional chemical resistance and an ultrahigh cryogenic bonding strength of 11.0 MPa at -196°C. This work establishes a supramolecular design principle that decouples service-life reinforcement from end-of-life chemical deconstruction, providing a general strategy for reconciling durability and recyclability in polymeric materials.