Research on anti-corrosion behavior of modified waterborne Acrylic-based coating containing CuO/Polyaniline nanocomposite on mild steel in 3.5 wt% NaCl solution

This research examines the anti-corrosion properties of an acrylic coating containing CuO/Polyaniline nanocomposite (CuO/PANI n-composite) and the effect of different composition percentages of the n-composite. Electrochemical tests were carried out on mild steel alloy in 3.5 % NaCl solution for 60 days in a saline environment. The electrochemical current noise (ECN) results of prepared coatings were interpreted using the wavelet method. The standard deviation of partial signal (SDPS) plots derived from wavelet, as well as the electrochemical impedance spectroscopy (EIS) technique demonstrated that the quantity of electric charge (Q) decreased with the addition of the n-composite, due to the decreased corrosion rate. Moreover, the modified coating with 20 % composition of the n-composite demonstrated more inhibiting effects in a short and long time compared to other compositions. The EIS measurements showed that the value of coating resistance for 20 % CuO/Polyaniline nanocomposite after 1 day immersion is 1510 kΩ cm2. The results indicated that the 20 % composition of the n-composite exhibited excellent inhibiting properties with an efficiency of 97.57 % and 97.62 % after 1 and 60 Immerging time/day, respectively. The prepared n-composite has been characterized using X-ray diffraction (XRD) analysis, Field-Emission Scanning Electron Microscopy (FE-SEM), and Transmission Electron Microscopy (TEM), which revealed suitable synthesis of the CuO/PANI n-composite. Therefore, this research demonstrates a successful approach to developing the anti-corrosion effect of acrylic coating by the incorporation of CuO/PANI n-composite. [Display omitted] •Modified acrylic coating exhibit good inhibition efficiency.•The SDPS plots are useful to investigate signals arrived from the local corrosion.•The 20℅ composition of CuO/Polyaniline nanocomposite illustrates the best performance.