Preparation of aniline trimer modified graphene oxide new composite coating and study on anticorrosion performance

Graphene oxide (GO) has attracted much attention in anticorrosive coating applications due to its excellent mechanical properties, thermochemical stability and large specific surface area. In this paper, aniline trimer modified GO composites (ATGO) were prepared through modifying GO at different temperatures of 65 °C, 80 °C, 95 °C, and 110 °C, respectively. Aniline trimer modified GO composite coatings (ATGO/EP) were then prepared by adding different quantities of ATGO to epoxy coating, with the mass fractions of 0.05%, 0.1% and 0.3%, respectively. The resulting composite coatings were then sprayed onto Q235 steel plates for characterization and anticorrosion testing. A series of characterization methods such as x-ray diffraction (XRD), Raman spectra, Fourier transform infrared spectroscopy (FT-IR), Atomic force microscopy (AFM) and Transmission electron microscopy (TEM) were used to prove that aniline trimer was successfully grafted on GO. The optimal reaction temperature for ATGO preparation was determined to be 95 °C. Using anticorrosive tests such as Electrochemical impedance spectroscopy (EIS), salt spray test and adhesion test, it was proven that the addition of ATGO can significantly promote anticorrosion performance of epoxy resin (E-44). The optimal addition amount of ATGO to prepare composite coatings was determined to be 0.05 wt%. Its coating resistance after soaking in 3.5% NaCl solution for 10 days was 6.87 × 10 ^6 Ω, which was two orders of magnitude higher than the 3.89 × 10 ^4 Ω of pure epoxy coating. The importance and originality of this study is that it explores an effective way to improve the anticorrosion performance of epoxy coatings.