Effect of inhibitor-loaded halloysite nanotubes on active corrosion protection of polybenzoxazine coatings on mild steel

Abstract The inhibitor-loaded halloysite nanotubes (HNT) were incorporated into polybenzoxazine coating for active corrosion protection of carbon steel. The morphology and structure of HNT nanocontainers were characterized by field emission scanning electron microscope (FE-SEM), transmission electron microscopy (TEM), and Fourier transform infrared (FTIR) spectroscopy, respectively. The amount of benzotriazole (BTA) loaded in the lumen of HNT was determined by thermogravimetric analysis (TGA). The release behaviour of inhibitors was characterized by UV–vis spectrometry. It is found that the HNT possessed an acid-responsive release property of BTA. The corrosion resistance performance of polybenzoxazine coatings doped with inhibitor-loaded halloysite nanotubes was investigated by the electrochemical impedance spectroscopy (EIS) measurement and scratch test. The results demonstrated that the anti-corrosion performance of polybenzoxazine coatings was effectively improved by doping with these inhibitor-loaded halloysite nanotubes.