In situ electrochemical synthesis of polyaniline/f-MWCNT nanocomposite coatings on mild steel for corrosion protection in 3.5% NaCl solution

Nanostructured composites increase their sensitivity and performance when employed as coating material in corrosive environments. This present study was conducted to elucidate the use of functionalized carbon nanotubes (CNTs) as reinforcement to enhance the corrosion and mechanical behavior of polyaniline (PANI) coatings for the protection of mild steel (MS) structures. Different techniques like Raman spectroscopy, ATR-IR and FESEM analysis were used to evaluate their structure and morphology. FESEM images of the fabricated PANI/f-CNT composites suggest excellent dispersion of CNTs in PANI matrix with one-dimensional core shell structure. PANI/f-CNT nanocomposite shows an improvement in the mechanical properties with an increase in the hardness value. Hydrophobic nature of nanocomposite coatings was verified by contact angle measurements. The evaluation of electrochemical corrosion behavior of nanocomposite coated MS was achieved by monitoring the anodic current potential polarization curves and electrochemical impedance response. Finally, it was concluded that PANI/f-CNTs nanocomposite coatings are potentially employed as anticorrosive coatings for mild steel against corrosive environment. (C) 2014 Elsevier B.V. All rights reserved.