Self-healing coating with the ability to mark damaged locations, based on electrospun photothermal fibers and AIE agents

The anti-corrosion coatings based on core-sheath fibers prepared by electrospinning methods are developed for the indication and repair of large-scale damage to coatings. The cores are the composite fluorescent agents composed of AIE-gens and CHEF-gens, which exhibit strong fluorescence characteristics sensitive to corrosion due to the CHEF and FRET effects. The composite fluorescent agents provided information about the location of damages when the coatings, with the fibers as the core materials, are damaged. The sheaths are photothermal materials, composed of photothermal responsive acid doped polyaniline and shape memory polyurethane. The photothermal properties of acid doped polyaniline, under the irradiation of an infrared laser, contributes to heating in the damaged areas. The softened and activated polyurethane simultaneously lead to interpenetration and entanglement of molecular chains at the closed damage sites, resulting in complete repair of the damaged coatings.