Corrosion inhibition of functional graphene reinforced polyurethane nanocomposite coatings with regular textures

In order to further enhance its anti-corrosion properties as a surface coating for protecting various materials from corrosion, polyurethane (PU) needs to be modified by adjusting the chemical composition and interface structure. In this work, a series of functionalized graphene (FG) reinforced PU nanocomposite coatings with regular texture were fabricated using a replication method. The structural and morphological properties of the as-prepared PU composite coatings were characterized by Fourier transform infrared spectroscopy, Raman spectroscopy, X-ray photoelectron spectrometer, transmission electron microscopy, scanning electron microscopy and atomic force microscopy. Results showed that FG was dispersed homogeneously in the PU matrix after chemical modification. Moreover, the morphology of the obtained coatings showed a circular cone with a diameter of 8 μm spaced 8, 6 and 4 μm apart, respectively. Most importantly, the presence of surface texture and well-dispersed FG effectively enhanced the anti-corrosion properties of the textured FG/PU composite coating. It is attributed to the hydrophobicity and barrier effect of the obtained coatings, which not only reduce the contact and interaction between water and the surfaces, but also increase the tortuosity of the corrosive medium diffusion pathway. The schematic was drawn to intuitively describe the anti-corrosion mechanism of functional graphene reinforced polyurethane nanocomposite coatings with regular textures.