Enhancement of anticorrosion property and hydrophobicity of modified epoxy coatings with fluorinated polyacrylate

Abstract

In this study, in order to improve the hydrophobicity and corrosion protection of epoxy coatings, a fluorinated polyacrylate polymer containing epoxy groups (PFEMA) was designed and used to modify epoxy resin. FT-IR, 1H-NMR and GPC were employed to characterize the structure of PFEMA polymer. Contact angle (CA), X-ray photoelectron spectrum (XPS), scanning electron microscope, Tafel curves, electrochemical impedance spectroscopy (EIS) and salt spray test were carried out to investigate the performance of fluorinated polyacrylate modified epoxy coatings. The incorporation of PFEMA polymer changes the hydrophilic nature of epoxy resin to hydrophobicity, and the CA shifts from 67° to 98° with the content of fluorinated polyacrylate increases from 0 to 10 wt%. EIS measurements show that the impedance modulus value of fluorinated epoxy coatings is higher compared to pure epoxy resin. Additionally, the corrosion rate also decreases and its value shifts from 4.223×10−8 mm/year to the lowest value of 9.696×10-9 mm/year with the increasing of fluorinated polyacrylate in epoxy resin, demonstrating that the corrosion resistance of epoxy coatings has been significantly strengthened after introduction of fluorinated polyacrylate.