文献类型：期刊文献

中文题名：智能阻锈剂LDH-NO_(2)在钢筋混凝土中的控释机制及缓蚀性能

英文题名：Controlled release mechanism and inhibition performance of smart inhibitor LDH-NO_(2) in the reinforced concrete structures

作者：文成[1,2];田玉琬[1,2];杨德越[1];王贵[1];邓培昌[1];董超芳[2]

机构：[1]广东海洋大学广东省海洋装备及制造工程技术研究中心,湛江524088;[2]北京科技大学北京材料基因工程高精尖创新中心,北京100083

年份：2022

卷号：44

期号：8

起止页码：1368

中文期刊名：工程科学学报

外文期刊名：Chinese Journal of Engineering

收录：CSTPCD、、CSCD2021_2022、EI(收录号：20224212968038)、Scopus、北大核心、CSCD、北大核心2020

基金：广东省基础与应用基础研究基金项目(2021A1515110382);湛江市科技计划项目(2021E05005)。

语种：中文

中文关键词：阻锈剂;层状双金属氢氧化物;控释;缓蚀;第一性原理计算

外文关键词：inhibitor;layered double hydroxide(LDH);controlled release;inhibition;density functional theory(DFT)

中文摘要：为解决传统阻锈剂过早失活、过量投放的问题,研究了一种具有控释、长效、靶向特征的智能阻锈剂LDH-NO_(2).采用第一性原理计算、物理检测技术、浸泡实验和电化学方法研究了智能阻锈剂LDH-NO_(2)的微观和宏观控释规律及缓蚀行为.结果表明:(1)在氯离子侵蚀或碳化的混凝土环境中,LDH-NO_(2)中的NO_(2)可快速、自发释放,1h内达到释放平衡,从而及时修复钢筋的腐蚀损伤;(2) LDH-NO_(2)对碳化环境比氯离子环境更加敏感,其与CO_(2)发生离子交换反应的化学能更大,反应产物的层间距更小、层间作用力更强、稳定性更好;(3)含氯碳化混凝土环境中,5 g·L^(-1)LDH-NO_(2)对碳钢钢筋的缓蚀效率约99%,使碳钢钢筋腐蚀速率下降一个数量级;(4)相较于传统阻锈剂NaNO_(2),智能阻锈剂LDH-NO_(2)可有效延长碳钢钢筋的腐蚀起始时间、减少其腐蚀面积、降低其腐蚀程度;(5) LDH-NO_(2)的缓蚀性能主要源于LDH对NO_(2)的释放,而非其对腐蚀性离子的吸附.因此,智能阻锈剂LDH-NO_(2)在钢筋混凝环境中具有优异的缓蚀性能和长效性.

外文摘要：Reinforcement corrosion is one of the most serious problems limiting the durability of concrete structures. Corrosion inhibitors are used as admixtures in the fresh concrete to prolong the service life of the concrete structure, and calcium nitrite is the most extensively tested admixed inhibitor. However, the premature deactivation and overdose of conventional inhibitors limit their application, and one strategy to solve this problem is to use smart inhibitors with controlled release, long-term effects, and targeting performance. In this paper, a smart inhibitor of LDH-NO_(2)was prepared based on the Zn-Al layered double hydroxide as a shell and the nitrite ions as a core. The first principles calculation, physical detection techniques, immersion test, and electrochemical methods were performed to study the micro-and macro-controlled release mechanism and inhibition property of LDH-NO_(2). The results show that:(1)The nitrites in LDH-NO_(2) can release spontaneously in the chloride-contaminated or/and carbonated concrete. The release process reaches equilibrium in 1h, repairing the corrosion damage of steel reinforcement in time.(2) The LDH-NO_(2)is much more sensitive in the carbonated concrete than chloride-included concrete,reflected in the greater energy of ion-exchange reaction and the more stable product with thinner interlayer with stronger interlayer force.(3) In the simulated pore solution of chloride-contaminated and carbonated concrete,the corrosion inhibition efficiency of 5g·L^(-1) LDH-NO_(2)on carbon steel reinforcement exceeds 99%,reducing the corrosion rate of carbon steel by one order of magnitude.(4) Compared with the conventional NaNO_(2)inhibitor,LDH-NO_(2)effectively prolongs the corrosion initiation time while decreasing the corrosion area of carbon steel reinforcement.(5) The corrosion inhibition performance of LDH-NO_(2)is mainly due to the release of NO_(2)from LDH rather than the corrosive ion adsorption on LDH.Therefore,the smart inhibitor of LDH-NO_(2)shows excellent corrosion inhibition and a long-term effect in the reinforced concrete environment.