| 摘要: |
| 涂层技术广泛应用于金属设备腐蚀防护，而针对传统涂层服役过程中的微损伤难以及时探测并修复，导致损伤后涂层防腐性能失效、金属腐蚀进程加速等问题。开发一种中空介孔 SiO2微球包覆 2-巯基苯并噻唑的自修复涂层，并对涂层的自修复性能进行全面表征测试。将包覆 2-巯基苯并噻唑的 SiO2微球作为填料，添加到无溶剂环氧树脂涂层中制备自修复涂层，在质量分数为 3.5%的 NaCl 溶液中探查受损涂层在铜基体表面的自修复过程。采用多种测试表征方法测试 SiO2 微球包覆 2-巯基苯并噻唑的可行性，对涂层的自修复机理进行深入分析，综合评价自修复涂层的防腐性能。采用溶胶-凝胶法对 SiO2 微球进行制备，制备的 SiO2微球具有中空结构，微球直径约为 623 nm。通过 XDR、FTIR 与 TG 等测试表征技术验证 SiO2微球实现对 2-巯基苯并噻唑的包覆，且负载量良好；通过 EIS 阻抗测试对自修复涂层的修复性能进行测试，经对照实验测试自修复涂层具有较为良好的防腐性能，并在 6 d 时防腐性能达到最大；通过 SEM、EDS 以及 SKP 等测试技术，从微观角度验证包覆 2-巯基苯并噻唑的 SiO2微球对损伤涂层的修复性能以及对铜基体的防腐性能。当涂层被划伤后，2-巯基苯并噻唑缓慢释放并通过强化学吸附与铜基体结合，在裸露金属基体表面形成一层保护膜，阻滞外部环境的腐蚀性介质对铜腐蚀，实现了涂层对损伤处的主动修复，在浸泡 6 d 后防腐效果显著。制备的包覆 2-巯基苯并噻唑 SiO2微球对损伤涂层具有一定的修复能力， 能够有效延长涂层的服役寿命。 |
| 关键词: 中空介孔 SiO2 微球 2-巯基苯并噻唑 自修复涂层 缓蚀剂 腐蚀防护 |
| DOI：10.11933/j.issn.1007?9289.20221223001 |
| 分类号:TG176 |
| 基金项目:国家自然科学基金（41976044）；山东省自然科学基金面上（ZR2021ME087）资助项目 |
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| Corrosion Protection Performance of a Self-repairing Coating with Hollow Mesoporous Silica Microspheres Loaded with 2-mercaptobenzothiazole |
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SHI Hao1, CHU Guiwen1, LI Zhengli1, SONG Liying2, JIANG Quantong3
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1.College of Mechanical and Electronic Engineering,Shandong University of Science and Technology, Qingdao 266590 , China;2.College of Safety and Environmental Engineering,Shandong University of Science and Technology, Qingdao 266590 , China;3.Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071 , China
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| Abstract: |
| In view of the corrosion of metal equipment in the marine environment, coating technology has been widely adopted to prevent metal corrosion. Microdamage to traditional coatings is difficult to detect and repair in time. Once microdamage has occurred, the failure of anti-corrosion performance follows, accelerating the corrosion process. To address this issue, a self-repairing coating has been developed that could adapt to the complex marine environment and repair microdamage intelligently. The self-repairing performance of the coating was comprehensively evaluated. Hollow mesoporous silica microspheres(HMSN) were selected as carriers for storing 2-mercaptobenzothiazole(MBT). The self-repairing coating was prepared with the addition of MBT-loaded HMSN. In this study, HMSNs were prepared and characterized using scanning electron microscopy and transmission electron microscopy. The prepared HMSN, by definition, had a hollow mesoporous structure, and the diameter of the microspheres was about 623 nm. The self-repairing coating was prepared by adding the MBT-loaded HMSN, accounted for 18 wt.% of the coating mass, as fillers to solvent-free epoxy resin coatings. The self-repairing process of the prepared coating was simulated on a damaged copper substrate in 3.5 wt.% NaCl solution. When the scratched coating was immersed in a corrosive environment, the MBT in each exposed HMSN was slowly released. The MBT was subsequently combined with the copper substrate through strong chemical adsorption, and an adsorption film was formed on the surface of the bare metal substrate. The film prevented the corrosion of copper from the corrosive medium in the external environment, and hence active repair of the coating damage was realized. As the immersion time increased, the scale of the adsorption film became larger, and the corrosion resistance increased. On the sixth day of the immersion, the corrosion resistance of the coating reached its maximum resistance value, and the coating repair was complete. Compared with the beginning of the immersion, the copper content decreased from 80.233 wt.% to 2.548 wt.% after the coating repair. The performance of the MBT-loaded HMSN coating was tested using various test and characterization methods. Firstly, X-ray diffraction spectrum characterization proved that the prepared HMSNs were amorphous, and the loading of MBT did not change the crystal structure of the HMSN. Secondly, infrared characterization confirmed that MBT was able to be loaded into the HMSN. Thirdly, thermogravimetric analysis showed that HMSN, as excellent nanocarriers, were used to encapsulate MBT with a 14 wt.% loading rate. Next, the anti-corrosion performance of the self-repairing coating was evaluated by electrochemical impedance spectroscopy, and was further confirmed by the scanning Kelvin probe microscopy. At the end of the study, the self-repairing mechanism was summarized and clarified, and process was described. The self-repair performance of the prepared coating was excellent according to a variety of test characterizations. In the complex corrosion environment, the self-repairing coating had the ability to repair coating damage, and thus has a high practical value. The service life of metal equipment coated with the proposed coating can be effectively prolonged because of the remarkable anti-corrosion effect of the coating, enabling working equipment to realize long-term operation. |
| Key words: hollow mesoporous silica microspheres 2-mercaptobenzothiazole self-repairing coating corrosion inhibitor corrosion protection |
