Preparation of textured epoxy resin coatings for excellent hydrophobicity and corrosion resistance

Abstract

Because of the severe corrosion of marine structural steel under the splash zone, it is proposed to prepare surface textures in widely used epoxy resin (ER) coatings to improve the hydrophobicity and corrosion resistance. However, the surface texture preparation technology of organic coatings is flawed and needs to be improved. Template method, one of the textured preparation technologies of organic coatings, has the trouble that the air bubbles, which diminish the coating quality. In this paper, the method of curing at room temperature and vacuum treatment is used to reduce the generation of air bubbles. Scanning electron microscope (SEM) images show the complete morphology and texture dimensions of the textured ER coatings. The hydrophobic properties of the textured ER coatings were systematically investigated, the contact angles of the textured ER coatings were significantly improved, and all the textured ER coatings samples met the hydrophobic criteria. And the wetting state model of the textured ER coatings was determined by modifying the Wenzel wetting mode. Furthermore, the electrochemical impedance spectroscopy (EIS) analysis of the textured ER coatings shows that the corrosion resistance is improved by two orders of magnitude compared to the smooth ER coatings. That shows excellent corrosion resistance, and the effect of the texture parameters on the corrosion resistance and hydrophobic properties of the textured ER coatings showed a high degree of consistency. The preparation technology of surface textured coatings has great potential in the preparation and application of marine anti-corrosion organic coatings.