High-Strength, Recyclable Multifunctional Elastomer with a Dynamic Covalent Supramolecular Network

The development of supramolecular elastomers that integrate excellent mechanical properties, energy dissipation ability, recyclability, and antibacterial performance is of great significance for cutting-edge fields such as flexible electronics and medical devices. However, achieving a balance and integration of these diverse functionalities remains highly challenging for existing material systems. To address this limitation, this study presents a supramolecular elastomer featuring a dynamic network constructed through the Diels-Alder reaction, UPy-grafted chitosan, and multiple hydrogen-bonding interactions. This multiscale design endows the elastomer with several groundbreaking attributes. Strain-induced crystallization initiated by UPy-grafted chitosan induces self-reinforcement, yielding a remarkable tensile strength of 49.75 MPa while maintaining an elongation at break of 1096.54% and a notable toughness of 227.41 MJ·m^-3. The dynamic network further imparts efficient self-healing capacity and enables closed-loop recyclability. Additionally, the elastomer exhibits antimicrobial properties attributed to the presence of cations in chitosan. A comprehensive analysis and validation of the gradient energy dissipation mechanism within the supramolecular elastomer are provided. This innovative design paradigm ensures the integration of multiple functionalities while offering promising opportunities for the development of intelligent, sustainable, and high-performance supramolecular elastomers.