Influence of Gamma Irradiation on a Fatty Acid Self-Assembling Coating of Copper

Abstract

Self-assembled molecules (SAMs) form layers on copper that have an advantage compared to traditional corrosion inhibitors because of the significant decrease of chemical application. The protective properties of such films can be improved by different procedures of application of the SAM layer. In this work, a SAM layer of elaidic acid, a monounsaturated long-chain fatty acid with trans geometrical configuration, was applied on copper surface. Gamma irradiation was used to improve the protective properties of the SAM layer toward corrosion in 3% NaCl. Influence of gamma irradiation on such layer's properties was studied by different electrochemical techniques (polarization measurements, EIS), contact angle measurements and FTIR analysis. The results have shown that gamma irradiation at doses 0.5–5 kGy improves the protective properties of the SAM. The surface film became thinner due to stronger adsorption and resulted in better ordering of molecules on the surface of the oxide film although the polymerization involving the participation of oxygen molecules has been initiated by irradiation.