UV Light Curable Self-Healing Superamphiphobic Coatings by Photopromoted Disulfide Exchange Reaction

Abstract

At present, numerous methods have been developed to prolong the durability of superamphiphobic coatings. These studies mainly focus on the repairing of coating surface morphology and the supplement of low surface energy materials. These self-healing methods are performed on the surface of the coatings, which will not be self-healed when deep damage occurs. To provide a viable strategy to self-heal deep damaged coatings such as tearing and sharp cutting, a series of UV light curable self-healing superamphiphobic coatings were fabricated by deposition of hydrophobically modified and functionalized Al2O3 nanoparticles (SMANP) on the surface of UV light curable polyurethane acrylic resin containing disulfide bond (DSPUA) and subsequent UV light irradiation. The resultant coating can repel both water and oil and performs excellent superamphiphobicity. With the help of the disulfide exchange reaction, the coatings perform excellent self-healing behavior after sharp cutting; the scratches gradually disappear, and the surface recovers to an integrated one. Meanwhile, the coatings can also restore their superamphiphobicity after heating or UV irradiation. Moreover, the effects of temperature, disulfide bond contents, and UV light irradiation on the self-healing performance of coatings were studied in detail. It has been demonstrated that increasing temperature or disulfide bond content can improve the self-healing performance of coatings; meanwhile, UV light irradiation can dramatically improve the self-healing rate. The current findings not only unlock more possibilities of fabricating self-healing superamphiphobic coating but also provide preliminary understanding of the self-healing kinetics based on disulfide exchange reaction.