Synergistic enhancement of self-healing and abrasion/corrosion resistance properties of marine anticorrosion coatings with SiO2 modified PA6 core shell nanofibers

The harsh and complex nature of the marine environment can easily compromise protective coatings and lead to corrosion of the carbon steel substrate. Therefore, a marine anticorrosion coating with synergistically enhanced self-healing, abrasion resistance, and corrosion resistance is studied in this work. Coaxial electrostatic spinning nanofibers with nylon 6 (PA6) as shell and two-component epoxy resin as core were modified with SiO₂ and then embedded in epoxy resin coatings to create self-healing anticorrosion coatings. Tensile test results demonstrated that the PA6 shell nanofibers increased the coating's tensile strength by 15%. Meanwhile, the abrasion resistance of the composite coating with 1%SiO₂ nanoparticle was enhanced by 33%. Tafel polarization curves showed that the inclusion of core-shell nanofibers in the coating resulted in a self-healing ability, with an impressive self-healing efficiency of 99%. Low-frequency impedance modulus of electrochemical impedance spectroscopy (EIS) results demonstrated an improvement of nearly two orders of magnitude compared to the pure epoxy coating. Experiments illustrated that the coatings developed in this study for marine anticorrosion exhibit a synergistic enhancement effect on self-healing performance, abrasion resistance, and corrosion resistance.