Anti-H2S corrosion property of bipolar epoxy-resin coatings
By Dong, Yuhua; Zhou, Qiong; Meng, Xiaoyu; Cong, Chuanbo; Su, Xiaomei
Published in Progress in Organic Coatings
2019
Abstract
SiO2 nanoparticles were modified with the surfactants sodium dodecylbenzene sulfonate and hexadecyl trimethyl ammonium bromide. The modified SiO2 nanoparticles were added to epoxy-resin coatings to obtain anion- and cation-selective coatings. Two kinds of bipolar epoxy-resin coatings were prepared by exchanging the sequence of anion- or cation-selective coating (i.e., cation/anion and anion/cation). The coatings were immersed in H2S solution, and electrochemical impedance spectroscopy was used to investigate their performance. Scanning electron microscopy and energy-dispersive X-ray spectroscopy were used to observe the morphology of the metals and metal/coating interface. Experimental results indicated that the coating sequence of inner and outer ion-selective coatings affected the protection performance of the bipolar coatings. The good protection property of the bipolar coatings was attributed to the existence of a space-charge region and an electric field between the inner and outer ion-selective coatings.