Impact of inhibitor loaded mesoporous silica nanoparticles on waterborne coating performance in various corrosive environments

This article is a contribution to the development of the smart, self-healing solutions in the context of corrosion protection of metallic materials based on nanotechnology. Mesoporous silica nanoparticles were successfully synthesized and loaded with two different corrosion inhibitors, 1-hydroxybenzotriazole and 8-hydroxyquinoline. Loaded particles were embedded in different concentrations in waterborne epoxy coating, and as such applied to low carbon steel substrates. A continuous immersion test in 3.5% NaCl solution, humidity chamber exposure, and salt spray exposure were performed. Successful synthesis of silica nanoparticles has been demonstrated using scanning electron microscopy and energy-dispersive X-ray spectroscopy characterization techniques. Fourier transform infrared spectroscopy was used to confirm the loading of inhibitors, while the quantity of loaded inhibitors was determined by thermogravimetric method. Anticorrosive performance of intact composite coatings was determined using electrochemical impedance spectroscopy and open-circuit potential measurements. Adhesive properties were determined using the pull-off test (ISO 4624). Significant improvement in corrosion protection performance has been demonstrated for coatings containing inhibitor-loaded nanoparticles.