Bioinspired fabrication of high strength hydrogels from non-covalent interactions

In nature, many soft supporting tissues capable of withstanding multiform external forces during various activities consist of high strength hydrogels (HSHGs) in their delicately organized structures, in which non-covalent interactions play an irreplaceable role in the formation of these HSHGs systems. Inspired by this, researchers have attempted to develop many strategies to construct HSHGs by introducing dynamic and reversible non-covalent interactions in polymer networks. In the last decade, various non-covalent interactions were employed as the enhancing factors to produce a series of multifunctional HSHGs in our lab. By incorporating dynamic non-covalent interactions into hydrogel systems, a myriad of intriguing properties have been unraveled, such as fatigue resistance, self-healing, thermoresponsiveness and/or pH responsiveness, self-recovery, shape memory, and remoldability/recyclability/reusability, and their encouraging applications have been explored as well. However, achieving functionalized HSHGs and extending them to a broad range of applications is still in its infancy. This article provides an overview of bioinspired construction of HSHGs by utilizing a variety of non-covalent interactions; their applications in diverse fields are also presented. Meanwhile, we point out the future development of non-covalent interaction-reinforced HSHGs and potential challenges.