Abstract In order to investigate the effect of adhesion on ionic resistance of coatings, non-pigmented epoxy/polyamide free film and applied coating were compared. The results obtained from electrochemical impedance spectroscopy (EIS) after various immersion times in 3.5 wt.% sodium chloride solution showed that the corrosion resistance of the free film attached to the steel surface was by approximately one order of magnitude less than the applied one, indicating the important role of adhesion on the anti-corrosion properties of coatings. For the applied coating, the first signs of corrosion products appeared after 20 days of immersion, while this time was reduced to merely 2 days for the attached free film. Coating capacitance data pointed out that saturation with water for the attached free film was faster and also the amount of absorbed water was higher than the applied coating. Gravimetric water uptake of epoxy/polyamide free film was also determined and compared via EIS data. In addition, epoxy/polyamide free films were placed as membranes against NaCl and KCl solutions with different concentrations. The concentration of alkaline ions in the solution was measured using the flame photometry technique. Among epoxy membranes, the degradation of the sample which faced 3.5 wt.% NaCl was more remarkable comparing EIS and FT-IR analysis.

中文翻译：

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游离膜与环氧涂层低碳钢之间的扩散和粘附关系

摘要 为了研究附着力对涂层耐离子性的影响，比较了无色环氧树脂/无聚酰胺膜和涂装涂层。电化学阻抗谱 (EIS) 在 3.5 wt.% 氯化钠溶液中浸泡不同时间后获得的结果表明，附着在钢表面的游离膜的耐腐蚀性比施加的低大约一个数量级，表明附着力对涂层防腐性能的重要作用。对于施加的涂层，在浸泡 20 天后出现腐蚀产物的第一个迹象，而对于附着的游离膜，该时间减少到仅 2 天。涂层电容数据指出，附着的游离膜的水饱和速度更快，而且吸水量也高于施加的涂层。还通过 EIS 数据确定和比较了不含环氧树脂/聚酰胺的薄膜的重量吸水率。此外，将不含环氧树脂/聚酰胺的膜作为膜放置在不同浓度的 NaCl 和 KCl 溶液中。使用火焰光度法测量溶液中碱性离子的浓度。在环氧膜中，与 EIS 和 FT-IR 分析相比，面对 3.5 wt.% NaCl 的样品降解更为显着。将不含环氧树脂/聚酰胺的薄膜作为膜放置在不同浓度的 NaCl 和 KCl 溶液中。使用火焰光度法测量溶液中碱性离子的浓度。在环氧膜中，与 EIS 和 FT-IR 分析相比，面对 3.5 wt.% NaCl 的样品降解更为显着。将不含环氧树脂/聚酰胺的薄膜作为膜放置在不同浓度的 NaCl 和 KCl 溶液中。使用火焰光度法测量溶液中碱性离子的浓度。在环氧膜中，与 EIS 和 FT-IR 分析相比，面对 3.5 wt.% NaCl 的样品降解更为显着。