A recent article described a smart epoxy coating with mesoporous silica nanoparticles loaded with calcium phosphate for corrosion protection. This however is not particularly new, as in the 1980s, a controlled release pigment based on calcium supported on silica was developed, and gave enhanced corrosion protection in several resin systems (Shieldex®)
During this study, calcium phosphate was encapsulated into mesoporous silica nanoparticles (MSN), and the effect of pH on the structure, morphology of the MSN, and the release of calcium phosphate from the MSN, was investigated. Epoxy coatings with encapsulated (3 wt%) and non-encapsulated (3 wt% and 5 wt%) calcium phosphate were formulated and their anti-corrosive performance was evaluated.
Results showed that encapsulation of the calcium phosphate as inhibitive pigment in the coating can enhance the anti-corrosive performance by preventing spontaneous pigment dissolution and controlled the pigment’s release from the coating, as did the 80s development.
The study was published in Progress in Organic Coatings, Volume 165, April 2022.
