Epoxy‐based PANI/zinc oxide/glass fiber nanocomposite coating for corrosion protection of carbon steel.

In this work, a nanocomposite based on conductive polyaniline (PANI) was polymerized, via reverse microemulsion polymerization, in the presence of phosphoric acid and dodecylbenzenesulfonic acid. Applied simultaneously, these acids act as dopants, increasing the solubility of PANI in organic solvents. They further improve the corrosion protection performance of PANI by forming phosphate‐metal complex on metal surface. Zinc oxide nanoparticles were added to the PANI mixture before introducing ammonium persulfate. The final product of polymerization was added to an epoxy resin which served as the matrix for the coating. In order to improve coating elasticity, which can enhance coating resistance against impacts, E‐glass fiber (GF) was added to the coating formulation. It was observed that, with an optimized w/w%, the PANI/zinc oxide/GF composite improved the coating characteristics. Coatings were further subjected to stress‐strain and DC polarization tests, and their cross‐sections were investigated at break point by means of SEM. DC polarization plots revealed that the addition of zinc oxide can also shift the corrosion potential of steel toward positive potentials. [ABSTRACT FROM AUTHOR]