Fast Click Crosslinking Bio-Inspired Adhesives With Tailored Hierarchical High Bonding and Exceptional Versatility

The sluggish room-temperature curing kinetics and low-temperature brittle failure of epoxy resins have long constrained their deployment in extreme environments. Although existing acceleration strategies can enhance curing rates, they are invariably accompanied by issues of intense exothermic heat release, cohesive embrittlement, and toxic emissions. Herein, inspired by mussel adhesive proteins, we present an interfacial-bulk synergistic optimization strategy that leverages triazolinedione-indole (TAD-indole) click chemistry to construct a room-temperature, second-scale curable epoxy adhesive (RTIA). This strategy exploits the TAD-indole cycloaddition reaction to form a high-density C-N crosslinked network, while concurrently endowing the crosslinking sites with dicarbonyl hydrogen bond acceptor functionalities, thereby achieving synchronous enhancement of cohesive strength and interfacial adhesion. The RTIA adhesive exhibits a dry shear strength of 9.42 MPa and retains 3.12 MPa after boiling water treatment, demonstrating stable performance across a broad temperature window from -196°C to 80°C. Notably, the indole moieties confer intrinsic antibacterial properties that effectively suppress bacterial adhesion. This heat-free curing mechanism fundamentally circumvents the adverse effects associated with conventional accelerators, enabling compatibility between instantaneous on-site processing and deployment in extreme environments and thereby establishing a new paradigm for the design of high-performance structural adhesives.