The effect of nano-Fe2O3 particles on the corrosion performance of waterborne polyurethane coating

Nano-composite coatings were formed by addition of nano-Fe2O3 to a specially developed waterborne polyurethane coatings systems. The nano-Fe2O3 composite coatings were applied on mild steel substrate in various concentrations of nanoparticles. In order to improve dispersion of iron oxide nanoparticles in polymer matrix and better chemical interactions between nanoparticles and polymer coating, the nanoparticles were surface modified with the Tetraethyloorthosilicate (TEOS) silane. Interaction of nano-particles with silane and stability of surface modified nanoparticles in the polymer matrix were demonstrated using FTIR and stability tests, respectively. The uniformity of coatings and dispersion of nano-Fe2O3 particles in the polymer coatings were investigated by SEM. The effect of adding iron oxide nanoparticles on the corrosion performance of coatings was studied using Tafel Polarization (POL) and Salt-Spray tests in NaCl solution. The results showed that addition of modified nanoparticles surprisingly improved the corrosion resistance of resultant coatings. Besides, coatings with high concentrations of nano-Fe2O3 particles (more than 0.6 wt. %) showed acceptable performance after 40 days of immersion in 3.5% NaCl solution

کلیدواژه ها:

Nanocomposite ، Nano-Fe2O3 ، polyurethane coatings ، POL ، TEOS