Ultra‐Tough and Recyclable Ionogels Constructed by Coordinated Supramolecular Solvents

AbstractThe mechanical properties of most hydrogels (ionogels) are considerably affected by covalently cross‐linked networks. However, the interactions between solvent/solvent molecules and solvent/polymer chains are usually ignored. Herein, a series of ultra‐tough ionogels were prepared via a supramolecular solvent, halometallate ionic liquid, in which cations and coordinating anions form a 3D supramolecular network. The linear polymer chains are physically cross‐linked with supramolecular solvents synergistically enhancing the strength (14.3 MPa), toughness (78 MJ m−3), and Young's modulus (55 MPa) of ionogels, effectively dispersing the stress concentration under load, and obtaining better fatigue resistance and higher fracture energy (198 kJ m−2). Furthermore, the reversible cross‐linking enables green recovery and recycling of ionogels, simply by water. This strategy shows broad applicability based on a variety of supramolecular solvents and coordinatable polymers.