The novel damage-reporting and self-healing coatings prepared by electrospinning technology based on AIE agents and photothermal shape memory polymer

Abstract

The self-healing coatings for metals aroused researchers' interest due to their spontaneous repair of coating damage. In this study, intelligent damage-reporting and self-healing anti-corrosion coatings were developed using electrospun fiber as the core functional materials. The fibers exhibited core–shell structures, with the core materials being the solutions of the composite fluorescence probe RTPE. The shell materials consisted of the photothermal shape memory polymer, namely, phosphotungstic acid modified polyaniline-polyurethane composite polymer. Rhodamine Tetraphenylethylene (RTPE) demonstrated water-triggered aggregation-induced emission (AIE) effects and also exhibited fluorescence response to corrosive factors such as hydrogen ions and iron ions at the damaged area of the coatings. Under the trigger of the infrared laser, the modified polyaniline converted light energy into heat, causing the softening of epoxy and the shape memory effect of polyurethane. These processes facilitated the closure and repair of the damage, thus restoring their anti-corrosion functionality. Phosphotungstic acid played a role in enhancing the photothermal efficiency. The self-healing mechanism reinforced the corrosion resistance of the coatings. The self-indicating feature for damaged areas provided guidance for artificial repair in regions that did not self-heal satisfactorily. The synergistic and intelligent functionalities of the prepared coatings foreshadowed the significant potential applications in marine and aerospace corrosion protection fields.