不同氯离子浓度下PPD对混凝土钢筋阻蚀效果电化学试验  

Electrochemical experiment on the corrosion inhibition effect of PPD on concrete reinforcement under different chloride ion concentrations

作　　者：徐滨 周文凯 李刚雷 XU Bin;ZHOU Wen-kai;LI Gang-lei(College of Architecture and Design Art,Shaoxing Vocational and Technical College,Shaoxing 312000,China;China Construction Eighth Engineering Division Rail Transit Construction Co.,Ltd,Nanjing 210046,China;State Key Laboratory of Silicate Materials for Architectures,Wuhan University of Technology,Wuhan 430070,China)

机构地区：[1]绍兴职业技术学院建筑与设计艺术学院,浙江、绍兴312000 [2]中建八局轨道交通建设有限公司,江苏南京210046 [3]武汉理工大学硅酸盐建筑材料国家重点实验室,湖北武汉430070

出　　处：《化学研究与应用》2024年第6期1383-1388,共6页Chemical Research and Application

基　　金：国家自然科学基金(52108170)资助。

摘　　要：钢筋腐蚀导致在役钢筋混凝土结构耐久性不足、服役寿命缩短的主因之一。为研究聚乙烯吡咯烷酮(PPD)对钢筋的阻蚀效果和机理,开展了一系列电化学试验和Raman光谱测试。结果表明:钢筋电极动电位极化曲线大致呈“<"形分布,当PPD浓度较低时,点蚀电位随浓度的增加显著升高,钝化区间长度增大;PPD对钢筋耐CI点蚀具有良好的阻蚀效果,耐点蚀CI^(-)浓度高达0.2mol/L;等效电路元件参数R_(ct)和n随PPD浓度的增加呈“Λ”形,而Y。变化曲线呈V”形,当浓度为30mg/L时,电化学反应受到抑制,钢筋表面最平滑;PPD促使孔隙液中的Fe(Ⅱ)离子更多地转化生成α-Fe_(2)O_(3)、Fe_(3)O_(4)等具有稳定化学性质的Fe(Ⅲ)化合物,包裹在钢筋表面形成致密的钝化膜。Corrosion of steel bars is one of the main causes of insufficient durability and shortened service life of in-service rein-forced concrete structures.A series of electrochemical experiments and Raman spectroscopy tests were conducted to investigate the corrosion inhibition effect and mechanism of polyethylene pyrrolidone(PPD)on steel bars.The results show that the polarization curve of the steel electrode shows a roughly"<"shaped distribution.When PPD concentration is low,the piting potential significant-ly increases with the increase of concentration,and the length of the passivation interval increases;PPD has a good corrosion inhibi-tion effect on the corrosion resistance of steel bars to CI pitting,with a Cl'concentration of up to O.2 mol/L for pitting corrosion re-sistance;The equivalent circuit component parameters Re and n show a"A"shape with the increase of PPD concentration,while Yo change curve shows a"V"shape.When PPD concentration is 30 mg/L,the electrochemical reaction is inhibited,and the surface of the steel bar is smoothest;PPD promotes more conversion and generation of Fe(Ⅱ)ions in pore fluidsα-Fe(Ⅲ)compounds with stable chemical properties,such as Fe_(2)O_(3) and Fe_(3)O_(4),wrap around the surface of steel bars to form a dense passivation film.

关 键 词：非离子型表面活性剂 最佳浓度 吸附竞争 阻蚀 RAMAN光谱 

分 类 号：O614.7[理学—无机化学]