Influence of newly synthesized titanium phosphates on the corrosion protection properties of alkyd coating

This study reports the effect of three new titanium phosphates Li0.5M0.25Ti2(PO4)3 (where M = Mn, Co and Ni) on the protective properties of alkyd resin films applied on carbon steel substrate in 3.5% sodium chloride solution. The performance of the coatings was evaluated by electrochemical impedance spectroscopy, oxygen and water permeability and pull-off adhesion measurements. It was found that titanium phosphates improve the corrosion resistance as well as the adhesion strength of alkyd resin coatings. The incorporation of titanium phosphates into the alkyd resin coating significantly enhances the pore resistance of the alkyd resin and decreases the coating capacitance. Lower water and oxygen permeability were observed for alkyd resin containing titanium phosphates, confirming formation of a protective layer on the surface. The order of anticorrosion performance of the three coatings was as follows: Li0.5Mn0.25Ti2(PO4)3 > Li0.5Co0.25Ti2(PO4)3 > Li0.5Ni0.25Ti2(PO4)3.