Anti-corrosion performance and mechanical properties of epoxy coatings containing microcapsules filled with linseed oil and modified ceria nanoparticles

In this study, the anti-corrosion and mechanical properties of epoxy coatings containing microcapsules filled with linseed oil and neat and modified ceria nanoparticles were evaluated. To this end, first, the surface of ceria nanoparticles was modified with Cerium (III) nitrate hexahydrate using different methods and then the corrosion resistance of linseed oil containing 1 wt% of nanoparticles was studied by electrochemical impedance spectroscopy (EIS). To evaluate the protection mechanism of cerium nanoparticles, the corrosion performance of linseed oil containing calcium carbonate and Zirconia nanoparticles was also studied. In the next step, urea formaldehyde microcapsule containing linseed oil and 1 wt% nano-ceria modified from the previous step, was synthesized via in situ polymerization in an oil-in-water emulsion. The results of EIS Test showed that the addition of ceria nanoparticles to the microcapsule's core content improves the anti-corrosion performance of the epoxy coatings containing microcapsules due to increased barrier properties as well as through inhibition mechanism. The mechanical properties of the coating samples decreased up to 35% by the addition of micro capsules due to disruption of the structural integrity of the resin matrix. However, the DMTA test revealed that the glass transition temperature of the samples did not change significantly by adding microcapsules to the coating samples.