Developing novel, environmentally friendly, and efficient corrosion inhibitors is of great significance for improving the durability of marine concrete against chloride ion erosion. This paper aims to explore the potential of layered double hydroxides (LDHs) as nanocontainers, incorporating organic corrosion inhibitors between LDHs layers to synergistically enhance their effectiveness. In this study, Mg/Al-pAB-LDH was synthesized through the interlayer modification of LDHs with an organic corrosion inhibitor, p-aminobenzoic acid (pAB), employing a calcination-rehydration method. Chloride ion (Cl−) adsorption behavior was quantitatively and qualitatively analyzed and the effect on mortar properties was investigated. The corrosion resistance of steel bars in the mortar was assessed under chloride salt simulated concrete pore solution (SCPs) and chloride salt wet-dry cycles via electrochemical tests and microscopic characterization of Mg/Al-pAB-LDH. The results demonstrate that Mg/Al-pAB-LDH efficiently captures Cl− and releases corrosion-inhibiting ions pAB, with the adsorption process conforming to pseudo-second-order kinetics and Langmuir adsorption isotherm. Mg/Al-pAB-LDH enhances the pore structure of mortar, effectively improving mechanical properties and resistance to chloride ion penetration, with the optimal effect observed at a 4 % addition rate. Mg/Al-pAB-LDH demonstrates outstanding corrosion resistance to steel bars in both SCPs and mortar. In SCPs, it serves as a corrosion inhibitor by adsorbing Cl− and releasing pAB, whereas in mortar, it functions as a corrosion inhibitor by enhancing the physical barrier effect of mortar, adsorbing Cl−, and releasing pAB. This study demonstrates the promising potential of utilizing Mg/Al-pAB-LDH as a novel corrosion inhibitor to mitigate the corrosion of steel bars in marine concrete.

中文翻译：

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有机腐蚀抑制离子层状双氢氧化物对水泥基材料性能和氯化物环境下加固腐蚀的影响


开发新型、环保、高效的缓蚀剂对于提高船用混凝土抗氯离子侵蚀的耐久性具有重要意义。本文旨在探索层状双氢氧化物 （LDH） 作为纳米容器的潜力，在 LDH 层之间加入有机缓蚀剂以协同增强其有效性。本研究采用煅烧-再水化法，用有机缓蚀剂对氨基苯甲酸 （pAB） 对 LDHs 进行层间改性，合成了 Mg/Al-pAB-LDH。对氯离子 （Cl-） 吸附行为进行了定量和定性分析，并研究了对砂浆性能的影响。通过电化学测试和 Mg/Al-pAB-LDH 的微观表征，在氯化盐模拟混凝土孔隙溶液 （SCPs） 和氯盐干湿循环下评估钢筋在砂浆中的耐腐蚀性。结果表明，Mg/Al-pAB-LDH 能有效地捕获 Cl− 并释放腐蚀抑制离子 pAB，吸附过程符合准二级动力学和 Langmuir 吸附等温线。Mg/Al-pAB-LDH 增强了砂浆的孔结构，有效改善了机械性能和抗氯离子渗透性，在 4% 的添加量下效果最佳。Mg/Al-pAB-LDH 对 SCP 和砂浆中的钢筋表现出优异的耐腐蚀性。在 SCPs 中，它通过吸附 Cl− 并释放 pAB 起到缓蚀剂的作用，而在砂浆中，它通过增强砂浆的物理阻隔效应、吸附 Cl− 和释放 pAB 起到缓蚀剂的作用。 本研究证明了利用 Mg/Al-pAB-LDH 作为新型缓蚀剂来减轻船用混凝土中钢筋腐蚀的潜力。