Study of the Anticorrosive Properties of Polypyrrole/Polyaniline Composite (as a Conductive Polymer) via Electrochemical Techniques

In this work, protective properties of polypyrrole/polyaniline composite (as a conductive polymer) have been investigated in 3.5% sodium chloride solution via electrochemical techniques (electrochemical impedance spectroscopy, corrosion potential measurements and anodic polarization tests). Polypyrrole / polyaniline composite was deposited on carbon steel substrate by potentiostatic method. The electric capacitance and resistance of the films were monitored with the immersion time to investigate the water permeability of the paint films. Polypyrrole/polyaniline composite had a relatively low permeability and good catalytic behavior on passivation of carbon steel in longer periods. The results showed that the composite had better anticorrosive behavior compared to homopolymers (polypyrrole and polyaniline). J. Color Sci. Tech. 1(2008), 57-65. © Institute for Colorants, Paint and Coatings.