This study aims to explore how the inhibitor-loaded nanocontainers can be used in the epoxy coating for protection of steel against corrosion. A self-healing anticorrosive coating can be easily fabricated by embedding the inhibitor-loaded nanocontainers into the epoxy coating matrices. For this purpose, first, cerium (a catholic corrosion inhibitor) is encapsulated into silica nanoparticles (SiO2@Ce). Thereafter, an epoxy nanocomposite coating has been prepared on steel substrate using these SiO2@Ce nanoparticles as nanofillers.
To examine the effect of SiO2@Ce nanocontainers on mechanical properties of epoxy coating, the abrasion resistance, impact resistance and adhesion strength of coating have been evaluated. To reveal the effect of SiO2@Ce nanocontainer on corrosion behavior of epoxy-coated steel, the electrochemical impedance spectroscopy (EIS) has been conducted in NaCl solution.
Transmission electron microscopy and scanning electron microscopy/Energy-dispersive X-ray spectroscopy analyses indicate that Ce3+ cations have been successfully loaded into the surface of silica nanoparticles (at the content of approximately 2 Wt.%). Mechanical tests of epoxy nanocomposite coatings indicate that the nanocomposite coatings with nanoparticles content of 2.5 Wt.% provide the highest values of abrasion resistance, impact resistance and adhesion strength. EIS results show that the presence of SiO2@Ce3+ nanocontainers increases both coating resistance and polarization resistance. Along with the improvement the coating barrier performance, Ce inhibitor plays an important role in improving the anticorrosive performance at the steel–electrolyte interface.
The application of self-healing epoxy/SiO2@Ce nanocomposite coatings for the protection of carbon steel is very promising.
