Graphene-induced enhanced anticorrosion performance of waterborne epoxy resin coating

In this work, waterborne epoxy resin E44 and graphene were employed as the matrix and nanofiller, respectively, to construct composite coatings with enhanced anticorrosion performance. XRD pattern and TEM observation indicated that the obtained graphene had a stacked structure of few-layer graphitic sheets with numbers of wrinkles. SEM observations revealed that no defects or microcracks existed on the surface of graphene/epoxy coatings and the internal micropores and microcracks were filled by graphene. FTIR spectra displayed that all the characteristic absorption peaks were attributed to the epoxy resin cured with polyamide. The Tafel polarization curves showed that, as the graphene addition amount increased, the corrosive potential increased and the corrosive current decreased. ESI results proved that the addition of graphene into epoxy coatings could not only increase the impedance arc in Nyquist plots, but also increase the impedance modulus at low frequency. Finally, the enhanced anticorrosion mechanism was proposed and discussed.