(1. 西安建筑科技大学 材料科学与工程学院，西安 710055；
2. 西安建筑科技大学 陕西省纳米材料与技术重点实验室，西安 710055；
3. 西北师范大学 化学化工学院，兰州 730070)
摘 要: 超疏水金属表面因其机械稳定性差在工业应用中易受到限制。为此，本文提出了一种新的方法以改善超疏水表面在外力作用下的机械稳定性。采用化学刻蚀结合阳极氧化法制备了具有阶梯-纳米线-纳米孔三元分级结构的铝合金，利用自制的电喷涂装置将多巴胺和NaIO4水溶液同时喷涂在分级铝表面，成功地沉积了聚多巴胺。再通过Schiff碱和Michael加成反应，将低表面能物质十八胺接枝到改性后的铝表面，得到超疏水铝。通过FTIR和XPS分析超疏水铝表面的化学成分。机械稳定性测试结果表明，即使在经受700 cm的砂纸磨损或500 g的喷砂冲击后，样品表面仍表现出优异的疏水性。在超声处理60 min后，与未添加聚多巴胺的表面相比，本文所制备的超疏水铝黏附性显著提高。这表明聚多巴胺作为铝基底与低表面能物质之间的过渡层，以类似双面胶的作用，可大幅提升超疏水表面的机械稳定性。
关键字: 铝合金；超疏水；聚多巴胺；机械稳定性
（1. College of Materials Science and Engineering, Xi’an University of Architecture and Technology, Xi’an 710055, China;
2. Shaanxi Key Laboratory of Nano Materials and Technology, Xi’an 710055, China;
3. School of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, China）
Abstract:The application of superhydrophobic metallic surface in industry is usually limited due to its poor mechanical stability. Herein, a new method was proposed to improve its mechanical stability evaluated by a series of external force. Al alloy with hierarchical structure was fabricated by chemical etching and anodization method in sequence at initial, which owned step-nanowire-nanopore ternary structure. And then, dopamine and NaIO4 aqueous were sprayed on the hierarchical Al surface simultaneously by a self-made electric spraying equipment and polydopamine was obtained successfully. After grafting low surface energy substance, octadecylamine, on the above modified Al surface by Schiff base or Michael addition reaction, super-hydrophobic Al was obtained according to FTIR and XPS analysis. In order to investigate its mechanical stability, a series of tests were operated and the results show that the super-hydrophobic Al surface retains excellent super-hydrophobicity even after friction for 700 cm with 360 mesh sandpaper or suffering from 500 g of sandblast impact. The results of ultrasound treatment for 60 min indicate that as-prepared super-hydrophobic Al possessed significantly enhances adhesion performance compared with that without polydopamine. All these results illustrate that the introduction of polydopamine as double-sided adhesive between Al substrate and low surface energy substance can obviously improve the mechanical stability of super-hydrophobic Al surface.
Key words: aluminum; superhydrophobic; polydopamine; mechanical stability
