Application of anticorrosion paints is a common way to protect metallic structures against degradation caused by environmental conditions (water, temperature and mechanical stresses). However, ageing conditions damage coatings and their protective properties. Knowing how these materials react in aggressive environments is mandatory. A previous study on commercial anticorrosive paints showed synergetic effects between ageing factors. Studies were carried out on model polymer resins used in epoxy coatings to know how ageing conditions impact their properties. The aim of this study is to obtain composites by adding pigment to a studied polymer resin. In this way, the influence of pigment on coatings behavior can be highlighted by comparison with previous results. The system contains Ti02 and DGEBA-DAMP. First, mechanical and thermal properties of composite free films were studied using DSC and DMA, and compared to those of the resin alone. Then, totally cured composite films were immersed in pure water at different temperatures to investigate water uptake and diffusion coefficients by gravimetry. Finally, composites were applied on steel panels and submitted to external mechanical stresses. These samples were submitted to an environment of NaCl 3 wt% solution and diffusion was followed by EIS. For each ageing process, mechanical properties were studied to show the influence of the pigment on coatings behaviors in an aggressive environment.
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