Electrochemical study of the polymer behavior of an epoxy coating on carbon steel in 3% NaCl using polarization curves and SIE

In this paper,authors studied the impact of carbon steel coatings by functional epoxy resin tgeda. the thickness of the deposited film on the substrate is estimated at 170 ± 10 μm. firstly,to evaluate this impact of coating,the authors used two electrochemical methods: the stationary method using the polarization curve,the transient method based on the electrochemical impedance spectroscopy,and scanning electronic microscopy (sem) were used in this study. the obtained results of this study showed that the corrosion current (icorr) is equal to 0,07 μcm-2 and the polarization resistance (rp) is equal to kω.cm2.this shows that the effect of the investigated coating of carbon steel by the resin is more effective in 3 % nacl compared to the uncoated one in the same medium. subsequently,we conducted a new formulation by adding a series of inorganic fillers in the matrix of protection tgeda/hardener (mda),teda/mda/load. the nature of the charges was 5% of zinc,5% of trisodium phosphate and their mixtures. the stationary and transient electrochemical studies are very interest in according to their stationary efficiency 90%,94%,99,6 % and 99,7% and the transient 93%,95 %,99,5 % and 99,7 %concerning respectively the formulations mp1 (tgeda/mda),mp2 (tgeda/mda/zinc),mp3 (tgeda/mda/trisodium phosphate) and mp4 (tgeda/mda/zinc/trisodium phosphate).