Research advances in UV-curable self-healing coatings

Self-healing is the ability of a material to recover from physical damage. Because self-healing is crucial to environmental protection and sustainable development, several photochemical approaches, including those involving disulfide group, reversible Diels–Alder reaction, hydrogen bond cleavage, reformation, photo dimerization, and self-filling system, have been used to develop self-healing coating. In this review, the similarities and differences among the approaches to achieving self-healing in synthetic coatings, particularly the approaches related to the preparation, self-healing mechanism, and self-healing efficiency of the coating, are described. Potential future development and application of photochemical approaches to the synthesis of self-healing coating are also discussed.