Dual-Function Double-Walled Microcapsules Effectively Improve the Wear Resistance and Anticorrosion of Epoxy Composite Coatings

In the exploration of new microcapsule self-healing coatings with exceptional abrasion and corrosion resistance, this study focused on employing dual-function polydopamine-modified poly(urea-formaldehyde)/graphene oxide (PUF/GO-PDA) double-walled microcapsules to endow the wear resistance and anticorrosion performance of epoxy resin coatings (EP). The synthesized double-walled microcapsules exhibit a rough surface with a particle size of approximately 68 ± 13 μm. The incorporation of GO-PDA enhanced the adhesion of microcapsules to the EP matrix. Compared to pure epoxy coatings, the coefficient of friction (COF) of epoxy coatings filled with 10 wt % microcapsules decreased from 0.691 to 0.039. The average COF and wear rate were 94.3 and 87.8% lower than that of pure epoxy coatings, respectively, Abrasion depth decreased from 19.923 to 6.102 μm. After a 15-day impregnation period, the impedance value and low-frequency impedance modulus of the scratch coatings were higher than those of the pure epoxy, respectively. The OIL@PUF/GO-EP scratched coatings show a slight decrease in |Z|0.01 Hz from 1.537 × 105 to 2.430 × 104 Ω·cm2 in 1–15 days. This study yields valuable insights into the design and development of dual-function polymer coatings with enhanced tribological properties and anticorrosion.