Effect of DBSA-doped PANI on the corrosion protection performance of GO/epoxy coatings

In this study, the anticorrosion effect of polyaniline doped with dodecyl benzene sulfonic acid (PANI-DBSA) in graphene oxide (GO)/epoxy coating is investigated. PANI-DBSA is effectively synthesized on the surface of GO via chemical polymerization, and its properties are investigated via a series of characterization methods. The PANI-DBSA/GO hybrid exhibits improved compatibility with organic resin. The anticorrosion performance of PANI-DBSA/GO coatings is assessed through water absorption tests, electrochemical impedance spectroscopy measurements, and adhesion strength tests. The results indicate that PANI reduces the water absorption of GO, and the favorable compatibility of PANI-DBSA/GO with epoxy resin minimizes coating defects and enhances the interfacial blocking for diffusion electrolytes. In this work, the PANI has no active function such as passivating the metal surface, it just serves to shield the hydrophilic GO surface and to improve compatibility between GO and the epoxy, attributing its low pigment content.