Polybenzoxazine/SiO2 nanocomposite coatings for corrosion protection of mild steel

• Corrosion resistance of the coating was improved using SiO2 nanoparticles.
• Morphology and wetting properties were studied upon electrochemical behavior.
• Interfacial interactions were enhanced by the reaction between two phases.

A series of nanocomposite coatings (PBS) consisting of silane functional polybenzoxazine (PB-TMOS) and SiO2 nanoparticles were developed for corrosion protection of mild steel. The influence of silica content on corrosion resistance of PBS coatings was investigated by electrochemical measurements. The surface chemistry of nanoparticles and its effect on morphology of the PBS coating was also studied utilizing Fourier Transforms Infrared Spectroscopy, 29Si Nuclear Magnetic Resonance and Scanning Electron Microscopy analyses. The results indicate that the presence of the covalent bond between nanoparticles and PB-TMOS, greatly improves the interfacial interactions at the polymer/filler interfaces resulting in a better corrosion performance.