A supramolecular polymer with ultra-stretchable, notch-insensitive, rapid self-healing and adhesive properties

Supramolecular elastomers, possessing excellent mechanical, reusable adhesivity, and rapid self-healing properties, are essential for use in various applications. Herein, we developed a novel polyamide-urea elastomer with metal-ligand interactions and hydrogen bonds forming synergetic double dynamic bonds. Physical crosslinking endows the polyamide-urea elastomer with extreme stretchability and rapid self-healing ability at room temperature. The representative polyamide-urea elastomer, DPPy1-Fe-2, can be stretched to 40x its original length without breaking, and has extraordinary notch-insensitive elongation of up to 3500%. Meanwhile, DPPy1-Fe-2 can fully restore its elasticity modulus within 5 min at room temperature, and the elongation also reaches 3000% after 30 min of healing. In addition, the unique dynamic bonds of the supramolecule enable it to repeatedly and firmly adhere to different surfaces. The shear strength of DPPy1-Fe-2 is restored to an appreciable 80% after the first detachment-reattachment cycle, with it still possessing excellent adhesive strength after multiple cycles. As a result, the supramolecular elastomer shows outstanding stretchability, tear-resistance, quick self-repairing, and reusable adhesivity, which will facilitate the progress of intelligent adhesivity and flexible electronics.