Effect of self-assembled tetraaniline nanofiber on the anticorrosion performance of waterborne epoxy coating

This work discusses the addition of tetraaniline based conducting nanofiber (TANF) on the anticorrosive properties of waterborne epoxy coatings on Q235 mild steel. TANF was synthesized by self-assembly of tetraaniline in 1 M HCl solution. The structure of TANF was characterized by the Fourier-transform infrared (FT-IR), Raman, X-ray diffraction (XRD) pattern, UV–vis spectra and photoelectron spectroscopy (XPS), and the morphology of TANF was used to investigate by scanning electron microscope (SEM) and scanning probe microscope (SPM). The self-assembled TANF possesses excellent solubility, tiny nanofibrous structure and reversible redox behavior, making it appropriate as a novel anticorrosive pigment for the waterborne coatings. Electrochemical impedance spectroscopic (EIS), polarizing curves and scanning vibrating electrode technique (SVET) were used to investigated the effect of TANF on the anticorrosion performance of epoxy coating. The results revealed that the waterborne epoxy coating containing 0.5 wt% TANF exhibited improved corrosion resistance properties compared to pure waterborne epoxy coating. The addition of electroactive TANI could facilitate to form a passive metal oxide layer beneath the coating as proved by characterization of rust layers by X-ray diffraction (XRD).