Rational design of non-hazardous phytic acid-functionalized graphene oxide for polymer nanocomposites toward reinforcing corrosion resistance performance applications

Abstract Corrosion protection of water-borne polyurethane (WPU) containing phytic acid-decorated graphene oxide (PG) for Q235 steel was investigated in this work. Natural and non-hazardous phytic acid (PA) was applied to modify graphene oxide (GO) for enhancing its dispersion and compatibility with WPU. The results of Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Thermalgravimetric analysis, and Atomic force microscopy demonstrated successful decoration of GO by PA. Scanning electron microscopy and Field-emission high-resolution transmission electron microscopy were used to reveal the morphology structures of GO and PG. The electrochemical impedance spectroscopy and polarization curves were applied to investigate the anti-corrosion performance of WPU loaded with PG nanoparticles. Results revealed that the WPU/PG composite coatings presented an excellent enhancement in long-term anti-corrosion performance. The reason was that the modification of GO by PA not only improved compatibility with WPU, enabling the formation of an efficient barrier to play a physical anti-corrosion effect, but also formed stable metal chelate complexes with iron ions. Moreover, WPU/PG0.05 has the best anti-corrosion ability and “self-healing” function to some degree. Therefore, the advantages of PG can be used as an effective anti-corrosion nanofiller in practical application.