Preparation and anticorrosion properties of polyaniline‐SiO2‐containing coating on Mg‐Li alloy
Abstract
Purpose
The purpose of this paper is to synthesise polyaniline‐SiO2 (PANI‐SiO2) composites and investigate the anticorrosion properties of polyaniline‐SiO2‐containing coating on Mg‐Li alloy.
Design/methodology/approach
The PANI‐SiO2 composites were prepared by in situ chemical oxidative polymerisation in phosphoric acid medium. The PANI‐SiO2 composites were characterised by Fourier transform infrared, X‐ray diffraction and scanning electron microscopy techniques. The coating consisted of PANI‐SiO2 composites and epoxy resin was formed on Mg‐Li alloy. The anticorrosion properties were investigated by open circuit potentials (OCP), electrochemical impedance spectroscopy (EIS) and potentiodynamic polarisation curves.
Findings
The results indicated that the PANI‐SiO2‐containing coating on Mg‐Li alloy demonstrated good anticorrosion properties in 3.0 wt% NaCl solution. It has been found that the OCP of PANI‐SiO2‐containing coating were able to maintain more noble potential values in comparison to pure epoxy coatings in 3.0 wt% NaCl solution. EIS analysis indicated that the resistance of PANI‐SiO2‐containing coating was more than 106 Ω cm2 in 3.0 wt% NaCl solution in immersion process. Furthermore, the corrosion current of PANI‐SiO2‐containing coating on Mg‐Li alloy showed a significant reduction.
Originality/value
Previous reports on PANI‐SiO2 composites were mostly focused on their conductivity and optical properties and there are few studies so far on their anticorrosion properties as protective coatings for Mg‐Li alloy.
Keywords
Citation
Chen, X., Shen, K. and Zhang, J. (2010), "Preparation and anticorrosion properties of polyaniline‐SiO2‐containing coating on Mg‐Li alloy", Pigment & Resin Technology, Vol. 39 No. 6, pp. 322-326. https://doi.org/10.1108/03699421011085812
Publisher
:Emerald Group Publishing Limited
Copyright © 2010, Emerald Group Publishing Limited