Abstract
In this work, urea-formaldehyde resin was applied to enhance the corrosion protection properties of an epoxy coating. The urea-formaldehyde (UF) resin was synthesized through in situ polycondensation and the coatings were prepared by ball-milling grinding. The UF powder and coatings were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transforms infrared spectroscopy (FTIR), sedimentation test, and electrochemical impedance spectroscopy (EIS). One major finding was that superior compatibility of UF resin with epoxy resin retained the high dispersion of UF in polymer matrix, leading to barely reunion during grinding. UF presented nano-scale size after grinding as shown by TEM measurements. In addition, there was not any flaw revealed from cross-sectional microstructural features of coatings. The UF resin has effectively prevented the corrosive medium from further permeating through diffusion channels to the interface between coating and steel substrate. Results further revealed that the UF resin could significantly reinforce the corrosion protection property of epoxy coatings on carbon steel substrate.
