Design strategy, properties and application of high-strength and tough hydrogel: A review

Hydrogels have garnered significant attention in diverse fields, including flexible electronics, biomedicine, and water treatment, owing to their unique physicochemical properties and biocompatibility. However, the inherent trade-off between mechanical strength and toughness in traditional hydrogels has severely limited their practical applications, particularly in load-bearing scenarios and harsh environments. To address this issue, extensive efforts have been devoted to developing high-strength and tough hydrogels through structural design and functional modification. This review systematically summarizes the core design strategies for enhancing the mechanical performance of hydrogels, including molecular network engineering, morphological structure optimization, filler-filled modification, and other innovative approaches. Furthermore, the applications of these high-performance hydrogels in various fields, such as flexible sensors, tissue engineering, and antifouling materials, are comprehensively discussed.