Iranian researchers from Amir Kabir University of Technology and University of Petroleum Industry produced epoxy/polyamide coatings with improved anti-corrosive and physic-mechanical properties by using zinc oxide nanoparticles.
Metallic structures are significantly damaged annually in the country, and corrosion is the main cause of the damage. Great volume of organic coatings is used for the protection of metals against corrosion. However, the use of nanoparticle-based coatings increases noticeably the lifetime of the metallic structures.
Due to small particle size and high specific area, zinc oxide nanoparticles are able to create a physical barrier against the diffusion of corrosive compounds into the coating and the surface of the metal. They also slow down the reaching of corrosive materials to the metal surface, and therefore, they increase the lifetime of the metallic structure.
In this research, epoxy/polyamide coatings were formulated in various concentrations of zinc oxide nanoparticles. Then, the raw samples were obtained by exposing the nanocomposite coatings to the pre-prepared metallic backgrounds. The desirable samples were synthesized by heating the samples in the oven at specific temperature and time. Finally, the properties of the coatings were determined by carrying out various experiments.
Nanoparticles improved the anti-corrosive properties of the epoxy coating by improving the blocking properties and ionic resistance of the coating. Experiments on the samples showed that the use of high concentrations of nanoparticles resulted in a decrease in the anti-corrosive and physic-mechanical properties of coating due to inappropriate distribution of nanoparticles.
The results of the research have been published in November 2011 in Progress in Organic Coatings, vol. 72, issue 3, pp. 410-422.