Effect of Incorporating TiO2 on the Corrosion Inhibition Behaviour of Poly(butadiene-co-acrylonitrile)-Polyaniline Dodecylbenzenesulphonate (NBR-PAni.DBSA) Blends

A pre-optimised poly(butadiene-co-acrylonitrile)-polyaniline dodecylbenzenesulphonate (NBR-PAni.DBSA) blend with useful electrical conductivity (in the region of 10(-3) S.cm(-1)) was prepared and the effect of incorporation of titanium oxide (TiO2) on its corrosion inhibition behaviour for carbon steel was successfully assessed for the first time. It was found that the electrical conductivity of this blend can be enhanced up to a magnitude order for TiO2 loadings, 20.0-22.5 wt %. As found from both total immersion and electrochemical corrosion tests, NBR-PAni.DBSA blends with 20.0-22.5 wt % of TiO2 are deemed to be the best corrosion inhibitor for carbon steel, either in acid or artificial brine environment. However, a blend consisting of very high TiO2 content (i.e. 25.0 wt %) showed a significant poorer corrosion inhibition behaviour for carbon steel due to its more serious phase separation and porosity problem between the NBR host matrix and TiO2.