Study on the anticorrosion and antifouling performance of magnetically responsive self-healing polyurethane coatings

The dispersivity of self-healing microcapsules plays a critical role in the self-repairing properties of coatings. However, resolving the aggregation phenomenon of self-healing microcapsules has been challenging due to their high surface energy. In this paper, we successfully developed magnetically responsive self-healing microcapsule (MS-TO@CA) and polyurethane (PU) coatings with biomimetic interface wet-adhesion patterned microstructures and realized the adsorption, automatic capture and dispersion of MS-TO@CA based on different patterned microstructure sizes, microparticle sizes and contents. COMSOL software was used to simulate the magnetic field design and distribution, and the magnetization phenomenon of the microstructure was analyzed. The optimal process for the preparation of a new type of magnetically responsive self-healing PU coating was proposed. Compared with the control group, the corrosion time of the metal under the action of the coating was delayed by 816 h, and the antifouling performance was improved by approximately 30 times. This work has guiding significance for prolonging the service life of metals and improving metal anticorrosion and antifouling.