The development of green and sustainable corrosion inhibitors for copper in a corrosive marine environment is highly desired. Herein, we studied the fatty acid-based amidine as the new type of renewable corrosion inhibitor. Stearamidine salt was used as a model inhibitor, and it was synthesized through stearonitrile intermediate with an excellent isolated yield of 88%. We used electrochemical (potentiodynamic polarization) and morphological (scanning electron microscopy) measurements to assess the corrosion inhibition efficiency of stearamidine in 3.0 wt.% NaCl at 300 K. We show that, in such a condition, the optimum inhibition efficiency of 96% was achieved using only 0.2 mM stearamidine. The results suggested the fatty amidine is a promising corrosion inhibitor for copper that is suitable in the saltwater ecosystem. The thermodynamic parameters of the interaction between the stearamidine and the copper surface were determined, and the result suggests that the adsorption process occurred accordingly with the Langmuir adsorption isotherm and involved both physisorption and chemisorption.

中文翻译：

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脂肪脒作为铜腐蚀抑制剂

非常需要在腐蚀性海洋环境中开发绿色和可持续的铜缓蚀剂。在此，我们研究了脂肪酸基脒作为新型可再生缓蚀剂。硬脂脒盐作为模型抑制剂，通过硬脂腈中间体合成，分离收率高达88%。我们使用电化学（动电位极化）和形态学（扫描电子显微镜）测量来评估硬脂脒在 3.0 wt.% NaCl 中 300 K 的腐蚀抑制效率。我们表明，在这种条件下，96% 的最佳抑制效率是仅使用 0.2 mM 硬脂脒即可实现。结果表明，脂肪脒是一种有前途的铜腐蚀抑制剂，适用于咸水生态系统。