Silane functionalization of titania-graphene oxide nanocomposite for superior anticorrosion polyurethane coatings on steel

Abstract

This research investigated the enhancement of anti-corrosion properties in polyurethane (PU) coatings on steel substrates through the Silane (N-(2-Aminoethyl)-3-aminopropyltrimethoxysilane) functionalization of Graphene Oxide (GO) with Titania (TiO₂) nanoparticles. Comprehensive characterization techniques, including Scanning Electron Microscopy (SEM), Transmission electron microscopy (TEM), Thermogravimetric analysis (TGA), Fourier Transform Infrared Spectroscopy (FTIR), X-Ray diffraction analysis (XRD), Brunauer-Emmett-Teller (BET), and electrochemical analyses, confirmed the effective integration of TiO₂ within GO layers. The SEM and TEM analyses showed uniform dispersion of TiO₂ nanoparticles, while TGA indicated improved thermal stability of the functionalized GO-TiO2 (fGO). FTIR and XRD analyses verified the composite's successful chemical bonding and structural integrity. BET analysis revealed a specific surface area and pore volume reduction from 505.540 m²/g and 0.867 cc/g for GO to 211.622 m²/g and 0.708 cc/g for fGO, respectively. The enhancement in anti-corrosion properties can be attributed to the uniform dispersion of TiO₂ nanoparticles within the GO matrix, which increases the coating's barrier properties by filling pores and voids. This prevents electrolyte penetration and enhances adhesion to the steel substrate, inhibiting corrosion. Electrochemical analysis demonstrated excellent corrosion resistance of fGO-modified PU coatings, with a maximum observed resistance of 0.821 TΩ.cm2. Salt spray tests further validated these findings, showing delayed and reduced corrosion due to the protective layer formed by fGO. These results highlight the potential of fGO-modified PU coatings as advanced protective materials for steel structures in corrosive environments.