CAJ | 학술논문

合成4种2,5-二芳基-1,3,4-噻二唑化合物，即2,5-二苯基-1,3,4-噻二唑（DPTD），2,5-二（2-羟基苯）-1,3,4-噻二唑（2-DHPTD），2,5-二（3-羟基苯）-1,3,4-噻二唑（3-DHPTD）和2,5-二（4-羟基苯）-1,3,4-噻二唑（4-DHPTD）。通过Tafel极化曲线和电化学阻抗研究4种油溶型噻二唑衍生物在50 mg·L?1硫-乙醇体系中的缓蚀性能，电化学测试表明：腐蚀液中添加噻二唑衍生物后，银片腐蚀得到抑制；随着缓蚀剂浓度增大，腐蚀电流密度减小，缓蚀效率增大；当缓蚀剂浓度为90 mg·L?1时，4种缓蚀剂DPTD、2-DHPTD、3-DHPTD和4-DHPTD的缓蚀效率分别为85.8%、94.6%、96.4%和97.1%。采用扫描电子显微镜和原子力显微镜观察其表面形貌，可知缓蚀剂在金属表面形成一层保护膜，阻止腐蚀物质与金属表面的接触，从而抑制银片腐蚀。经分子动力学分析可知，4种噻二唑衍生物吸附于金属表面遵循Langmuir等温方程，且吸附属于以化学吸附为主的混合型吸附。量子化学计算和分子动力学模拟研究表明，4种缓蚀剂均具有很好的缓蚀作用，且4种缓蚀剂的缓蚀效率大小顺序是[4-DHPDT]＞[3-DHPDT]＞[2-DHPDT]＞[DPDT]，这与实验结果一致。
합성4충2,5-이방기-1,3,4-새이서화합물，즉2,5-이분기-1,3,4-새이서（DPTD），2,5-이（2-간기분）-1,3,4-새이서（2-DHPTD），2,5-이（3-간기분）-1,3,4-새이서（3-DHPTD）화2,5-이（4-간기분）-1,3,4-새이서（4-DHPTD）。통과Tafel겁화곡선화전화학조항연구4충유용형새이서연생물재50 mg·L?1류-을순체계중적완식성능，전화학측시표명：부식액중첨가새이서연생물후，은편부식득도억제；수착완식제농도증대，부식전류밀도감소，완식효솔증대；당완식제농도위90 mg·L?1시，4충완식제DPTD、2-DHPTD、3-DHPTD화4-DHPTD적완식효솔분별위85.8%、94.6%、96.4%화97.1%。채용소묘전자현미경화원자력현미경관찰기표면형모，가지완식제재금속표면형성일층보호막，조지부식물질여금속표면적접촉，종이억제은편부식。경분자동역학분석가지，4충새이서연생물흡부우금속표면준순Langmuir등온방정，차흡부속우이화학흡부위주적혼합형흡부。양자화학계산화분자동역학모의연구표명，4충완식제균구유흔호적완식작용，차4충완식제적완식효솔대소순서시[4-DHPDT]＞[3-DHPDT]＞[2-DHPDT]＞[DPDT]，저여실험결과일치。
Four 2,5-diaryl-1,3,4-thiadiazole compounds, namely, 2,5-diphenly-1,3,4-thiadiazole (DPTD), 2,5-di(2-hydroxyphenly)-1,3,4-thia-diazole (2-DHPTD), 2,5-di(3-hydroxyphenly)-1,3,4-thiadiazole (3-DHPTD), and 2,5-di(4-hydroxyphenly)-1,3,4-thiadiazole (4-DHPTD) were synthesized. Their corrosion-inhibiting performance in S-ethanol system was evaluated by Tafel polarization and electrochemical impedance spectroscopy (EIS). Electrochemical experimental results showed that all the thiadiazole derivatives were excellent inhibitors. The corrosion current decreased and the inhibition efficiency increased with increasing concentrations of the inhibitors. The optimum concentration was 90 mg·L?1, while the inhibition efficiency of DPTD, 2-DHPTD, 3-DHPTD and 4-DHPTD was 85.8%, 94.6%, 96.4% and 97.1%, respectively. Scanning electronic microscope (SEM) and atom force microscope (AFM) were also carried out, and confirmed the existence of the adsorbed film which was prevailed in addition of thiadiazole derivatives. The adsorption of these compounds onto silver surface from 50 mg·L?1 S-ethanol was followed the Langmuir adsorption isotherm and attributed to mixed-type adsorption mainly dominated by chemisorption. Quantum chemical calculations and molecular dynamic simulations also demonstrated that thiadiazole derivatives were good inhibitors. The experimental results showed that the order of inhibition efficiency was [4-DHPDT]>[3-DHPDT]>[2-DHPDT]>[DPDT], which was agreed with the theoretic method.