Tunable binary supramolecular interactions enabling biomimetic adhesives with switchable robustness and dynamic...

Supramolecular adhesives are promising smart materials for diverse industrial and daily applications. However, integrating the seemingly contradictory characteristics of high adhesion strength and rapid dynamic response within a single system remains a significant challenge. Herein, we present a simple binary supramolecular system composed of α-lipoic acid (αLA) and cyclen that enables dual-mode adhesion through precise control of molecular stoichiometry. At a molar ratio of 1:0.25 (αLA:cyclen, LC), the resulting LC_0.25 adhesive exhibits ultra-high shear strength (up to 23.48 MPa on Al₂O₃ ceramic), underwater adhesion capability, and good biocompatibility, with performance on glass comparable to commercial adhesives. In contrast, LC_0.5 demonstrates rapid adhesion kinetics, achieving 3.35 MPa on glass within 2 min, along with temperature sensitivity and reusability, surpassing previously reported counterparts. Mechanistic studies reveal that this performance switching originates from a stoichiometry-dependent balance between hydrogen-bonded networks and electrostatic interactions. Moreover, the dynamic molecular interactions, combined with a stable supramolecular network, endow the LC_0.25 elastomer with self-healing capability. This work provides a straightforward strategy for designing adaptive, high-performance adhesives.