Covalently functionalized ethylene diamine modified graphene oxide poly-paraphenylene diamine dispersed polyurethane anticorrosive nanocomposite coatings

Abstract Ethelynediamine modified graphene oxide (MGO) covalently functionalized with poly(p-phenylenediamine) (MGO-PPPDA) nanofiller was synthesized and characterized by Fourier transform infrared spectroscopy (FTIR), X-Ray diffraction analysis (XRD), and Transmission Electron Microscopy (TEM). Their composites were formulated using safflower oil polyurethane (PU) viz; MGO/PU, PPPDA/PU, and MGO-PPPDA/PU through 0.5 wt.% dispersion of these (MGO, PPPDA and MGO-PPPDA) nanofillers via ultra-sonication. Their coatings were prepared on carbon steel. The corrosion protective performance of these coatings were investigated under harsh acidic environments (5 wt.% HCl and H2SO4) with the help of potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS) and salt spray techniques. The results revealed that the synergistic effect of both MGO and PPPDA within a single PU matrix remarkably enhances the corrosion protection ability of MGO-PPPDA/PU than those of MGO/PU and PPPDA/PU nanocomposite coatings.