Self-healing polymer hydrogel based on dynamic chemical bonds

Polymer hydrogel is a soft material with a three-dimensional network structure that can absorb and retain a large amount of water. Polymer hydrogels have good biocompatibility, mechanical properties and important application value in biomedical and bioengineering fields. Self-healing hydrogels are smart hydrogels that respond to external stimuli and repair their own damage. Compared with the traditional hydrogel, the self-healing hydrogel has the property of repairing damage, and received extensive attention in the scientific field in recent years. Dynamic chemistry-based self-healing hydrogels are novel self-healing hydrogels that can reshape three-dimensional network structures by dynamic covalent or non-covalent bonding to repair damage. The new self-healing hydrogel can quickly repair its own damage and has good environmental adaptability, laying the foundation for the development of self-healing hydrogels as multifunctional new materials. The research progress of recent self-healing hydrogels based on dynamic chemistry was reviewed in this paper, especially focusing on the updated development on self-healing hydrogels based on hydrogen bonds, metal coordination interactions, host-guest interactions, ionic bonds, hydrophobic interactions, imine bonds/acylhydrazone bonds, borate bonds and disulphide bonds, and meanwhile, the problem of self-healing hydrogels was put forward, and the future direction of development was finally predicted.