Preparation and Anticorrosion Mechanism of Citric Acid Doped Polyaniline Nanotubes in Epoxy Coating

ABSTRACT In this work, citric acid doped polyaniline nanotubes (PANI‐NTs) were prepared through a one‐step method to enhance the anticorrosion property of epoxy coating. PANI‐NTs have a hollow tubular structure with the average diameter and wall thickness of 209 and 67 nm. Polarization curves and EIS results confirmed that PANI‐NTs presented a remarkable corrosion inhibiting effect for AA2024 aluminum alloy in 3.5 wt.% NaCl solution. Epoxy coating containing 1 wt.% of PANI‐NTs manifested an excellent anticorrosion performance and obvious self‐healing function. The prominent corrosion inhibiting function of PANI‐NTs is attributed to the strong synergistic effect between citric acid and PANI. Hence, PANI‐NTs can be used as a high efficiency anticorrosive pigment to promote the anticorrosion performance of epoxy coatings in thefuture.