A Robust, Universal, and Thermally Reversible Supramolecular Polyurethane‐Urea Adhesive

Developing smart adhesives that combine high bond strength, broad applicability, and on‐demand reversibility remains a long‐standing challenge in materials science. This study prepared a high‐performance polyurethane‐urea (PUU) supramolecular adhesive with multi‐modal interfacial interactions by precisely controlling molecular chain architecture. Experimental results demonstrate that the optimized PUU‐40 achieves a peak lap shear strength of 7.75 MPa on aluminum substrates, with a high peel work of 6.46 kN/m, exhibiting exceptional mechanical toughness. Thermodynamic analysis reveals that PUU‐40's extremely low interfacial tension (0.19 mN/m) ensures outstanding wettability and molecular‐level contact. Furthermore, leveraging synergistic effects of hydrogen bonding, coordination bonds, and electrostatic interactions, the adhesive exhibits universal bonding capability across diverse substrates including metals, polymers, and biomass. Crucially, the material demonstrates outstanding thermal reversibility, retaining over 84.43% of its strength after multiple cycles. This makes it a highly promising sustainable bonding solution for repairable electronics and advanced structural assemblies.