Fabrication of Highly Effective Polyaniline Grafted Carbon Nanotubes To Induce Active Protective Functioning in a Silane Coating

Neat silane coatings only provide barrier protection for the substrate subjected to corrosive media; therefore, the inclusion of efficient corrosion inhibitor in silane coating is vital to achieving active protection at defect sites of coatings. Elucidating the role of polyaniline (PANI) as a modifier for functionalized carbon nanotubes (CNTs) in the silane matrix to achieve active protection is the aim of this study. Different methods such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), Raman spectroscopy, zeta potential (ZP), and field emission scanning electron microscopy (FESEM) were employed to examine the structure of functionalized CNTs. FESEM images showed an increase in the diameter of nanotubes after modification proving the good grafting of PANI on the CNTs' surface, which was also confirmed by Raman, FTIR, and XRD measurements. Electrochemical impedance spectroscopy (EIS) was conducted on intact and scratched coatings. Results revealed a dual active-barrier effect of PANI grafted on CNTs in the silane coating protection.