Preparation and Anticorrosion Properties of Magnetically Controlled Rough Surface Hydrophobic Coatings of MZ-67...

In this study, a magnetically controlled rough surface was prepared as a top coating to endow the coating with hydrophobicity. This hydrophobic surface coating interacted with the bottom coating to form an epoxy anticorrosive coating with both active and passive corrosion protection. The formation of the magnetically controlled rough surface is attributed to the magnetic composite (MZ-67) dispersed in the epoxy resin emulsion being subjected to the external magnetic field on the particles and the interparticle interaction force, and the particles will undergo a positional shift driven by these two forces, resulting in the formation of an irregular mountainous concave-convex structure on the surface of the coated samples (magnetically controlled rough surface). FTIR, XRD, SEM, TGA, XPS, BET, and other experimental results proved the successful synthesis of the MZ-67 magnetic material, and the results of VSM experiments proved that the MZ-67 material has magnetic properties and can form magnetically controlled surfaces in the epoxy resin. The results of water contact angle experiments (WCA) of the surface coatings of the coated samples showed that the contact angle of the coatings was increased from 87.3 to 133.2° after modulation by an external magnetic field. The surface property of the coating changed from hydrophilic to hydrophobic. The results of electrochemical alternating current impedance spectroscopy (EIS) experiments illustrated that the corrosion resistance of the coatings after magnetic field modulation was significantly improved, and the coatings still possessed a low-frequency impedance modulus of 4.34 × 10⁸ Ω·cm² after being immersed in a 3.5 wt % NaCl solution for 60 days.