Robust and Reversible Supramolecular Adhesive via Dynamic Covalent Bond Crosslinking-Induced Assembly of Metal-Coordinated Nanoparticles.

Supramolecular adhesives, praised for their stimuli-responsiveness and reversibility, have gained significant attention. However, most of these adhesives demonstrate low tolerance to extreme environments and exhibit diminished adhesion performance after cyclic adhesion testing. Herein, a hierarchical self-assembly strategy is introduced for the construction of supramolecular polymer networks (poly(UIO-TA)) through dynamic disulfide bond crosslinking-induced assembly of metal-coordinated nanoparticles (UIO-TA). The UIO-TA were synthesized via a stepwise coordination-driven assembly process, wherein the zirconium ion coordinated with terephthalic acid and thioctic acid. Furthermore, these UIO-TA were crosslinked through ring-opening polymerization of dynamic disulfide bonds, resulting in the formation of poly(UIO-TA). Poly(UIO-TA) exhibited tough, durable, and reversible adhesion on diverse substrates, maintaining its effectiveness under mild to harsh conditions, including high temperatures (120 °C), organic solvents (e.g., dimethyl sulfoxide, ethanol), and strong acids (e.g., sulfuric acid). The adhesion performance of poly(UIO-TA) is superior to poly(thioctic acid) (poly(TA)) and most reported supramolecular adhesives. These attributes can be ascribed to the synergistic interplay of metal coordination bonds, hydrogen bonds, and dynamic disulfide bonds. Notably, after the five-cycle adhesion tests, the adhesion strength of poly(UIO-TA) increased by ≈2.5 times, which can primarily be attributed to increased cohesion energy resulting from the further ring-opening polymerization of disulfide bonds.