SiC/Al复合材料超疏水表面的制备

采用化学刻蚀法在SiC/Al复合材料表面构筑微纳结构,通过SEM和表面接触角测量仪分析刻蚀表面的微观形貌特征及润湿特性,并探讨了其与刻蚀时间之间的关系;借助热震试验评价SiC/Al复合材料超疏水表面的温度骤变耐受特性。结果表明:弥散分布的微米级SiC颗粒的存在使得刻蚀后的SiC/Al复合材料表面易形成由微米级粒状结构和纳米级凹坑结构复合而成的微观结构;氟硅烷修饰后的蚀刻表面的接触角最高达到166.8°,滚动角最低为3°,具有很好的超疏水特性;SiC/Al基超疏水表面具有较好的耐受温度骤变特性。     

ZnO/E-51复合涂料上超疏水表面的制备

采用ZnO和环氧树脂机械搅拌制备ZnO/E-51复合涂料,通过真空袋压、室温固化成型,再通过化学刻蚀与表面修饰,在ZnO/E-51复合涂料上制备出超疏水表面。采用扫描电镜和动/静态接触角分析仪,表征表面的形貌和疏水性。结果表明化学刻蚀在复合涂料表面构建了具有微-纳米尺度二元粗糙结构;采用1%(质量分数)的硬脂酸修饰,可改变复合涂料表面微-纳米尺度二元粗糙结构,影响表面的疏水性能,当修饰时间为30min时,其表面与水的平均接触角最高达152.21°。     

静电纺丝制备CMCAB超疏水纤维材料

以环境友好的纤维素衍生物羧甲基纤维素醋酸丁酸酯(CMCAB)为原料,采用静电纺丝技术构筑仿生粗糙疏水表面,成功制备了CMCAB超疏水纤维材料(接触角155°)。采用SEM研究了不同溶剂体系下纤维的直径和表面形貌,质量比为8∶2的二氯甲烷和乙醇混合溶剂制备的纤维表面粗糙。通过原子力显微镜测试,材料表面凹凸起伏,具有类似荷叶的微结构。测定材料的接触角,发现纤维的直径和粗糙度是影响疏水性的关键。在此基础上,为提高材料的疏水性,研究了溶液浓度和电压对纤维平均直径的影响规律,优化了制备CMCAB超疏水材料的纺丝工艺。     

One-step production of superhydrophobic coatings on flat substrates via atmospheric Rf plasma process using non-fluorinated hydrocarbons

This paper describes the direct deposition of hydrocarbon coatings with a static water contact angle higher than 150 using simple C6 hydrocarbons as a reactive gas in helium plasma generated in ambient air without any preroughening of the silicon (100) substrate. The film morphology and hydrophobicity are found to strongly depend on the structure of the reagent hydrocarbon. The films deposited with n-hexane and cyclohexane exhibited relatively smooth morphology and the water contact angle was only ～95°, similar to polypropylene. When benzene was used as a main reactive gas, the deposited film surface showed nanoscale textured morphology and superhydrophobicity with a water contact angle as high as 167°. Because the plasma is generated in air, all films show some degree of oxygen incorporation. These results imply that the incorporation of a small amount of oxygenated species in hydrocarbon films due to excitation of ambient air is not detrimental for superhydrophobicity, which allows the atmospheric rf plasma with the benzene precursor to produce rough surface topography needed for superhydrophobicity.     

玻璃纤维增强环氧复合材料上超疏水表面层的制备

先采用真空袋压法制备含CaCO3/环氧树脂表面功能层的玻璃纤维增强环氧树脂复合材料,再通过化学刻蚀与表面修饰,在玻璃纤维增强环氧树脂复合材料上制备出超疏水表面。采用扫描电镜和动/静态接触角分析仪,表征表面的形貌和疏水性,结果表明,在复合材料表面构建了具有微-纳米尺度二元粗糙结构;采用1%(质量分数)的硬脂酸修饰后,其表面与水的接触角最高达160.03°;制备的超疏水表面结构在室温环境下具有长期的稳定性。     

碳化硅颗粒增强复合材料超疏水表面的制备

采用电化学蚀刻方法在碳化硅颗粒增强复合材料(SiC/Al)表面构筑了微纳结构, 重点分析了蚀刻电流密度和蚀刻时间等关键操作参数对所得表面微观形貌及润湿特性的影响。研究发现, 较高电流密度(6 A/dm²)下刻蚀的SiC/Al复合材料表面可形成由微米级“粒状”结构和纳米级结构(颗粒状和波鳞状)复合而成的微-纳双层结构, 且这种特殊结构不因后续刻蚀时间延长而改变; 优化条件形成的SiC/Al复合材料刻蚀表面呈现出静态接触角高达160.7°、滚动角低至4°的超疏水特性。本研究结果说明SiC/Al复合材料可用于制备自清洁表面。     

Easy route to the wettability cycling of copper surface between superhydrophobicity and superhydrophilicity

A hierarchical copper structure combining micro- and nanogaps/pores was built up on copper substrate by etching and electrodeposition. The fresh as-deposited copper was easily oxidized in air at room temperature, forming a CuO layer covering on the surface. The surface could be hydrophobized with thiol-modified fluorocarbons, after which it showed a water contact angle as high as 165° ± 2°. This surface could also regain the superhydrophilicity with a zero water contact angel after annealing at 200 °C for 10 min to desorb the low surface energy monolayer of thiol-modified fluorocarbons and reform a CuO layer again on the surface. Repeating the process of adsorption/desorption of the monolayer by modification and annealing, it was successful to fulfill the wettability cycling between superhydrophobicity and superhydrophilicity on the copper surface. The adsorption and desorption mechanism of the monolayer was discussed based on the result of surface chemistry analysis.     

A combined etching process toward robust superhydrophobic SiC surfaces

Large-scale porous SiC was fabricated by a combination of Pt-assisted etching and reactive ion etching. It was found that the surface roughness of combined etchings increased dramatically in comparison with metal-assisted etching or reactive ion etching only. To reduce the surface energy, the porous SiC surface was functionalized with perfluorooctyl trichlorosilane, resulting in a superhydrophobic SiC surface with a contact angle of 169.2°?and a hysteresis of 2.4°. The superhydrophobicity of the SiC surface showed a good long-term stability in an 85?°C/85% humidity chamber. Such superhydrophobicity was also stable in acidic or basic solutions, and the pH values showed little or no effect on the SiC surface status. In addition, enhancement of porosity-induced photoluminescence intensity was found in the superhydrophobic SiC samples. The robust superhydrophobic SiC surfaces may have a great potential for microfluid device, thermal ground plane, and biosensor applications.     

The growth and superhydrophobicity of a perfluorocarbon nanoneedle array on an SiO/sub 2/ surface

Alternate employment of etching gas (SF/sub 6/) and deposition gas (C/sub 4/F/sub 8/) on an unpolished SiO/sub 2/ surface in an inductive coupling plasma system generates a perfluorocarbon nanoneedle array at low pressure and at ambient temperature. The nanoneedle averages 300 nm in diameter and the nanoneedle surface has a large water contact angle of 171/spl deg/. The superhydrophobicity of the perfluorocarbon nanoneedle surface may be used in many industrial and biological processes.     

超疏水SiO2/PS 薄膜于木材表面的构建

通过溶胶-凝胶法一步合成疏水性且具备独特形貌的二氧化硅粒子,联合聚苯乙烯以滴涂的方式于木材表面仿生合成了稳定性超疏水薄膜。经处理后的木材表面与水的静态接触角为153°,滚动角小于5°。通过扫描电子显微镜照片观察到该复合涂层拥有微米/亚微米的二维等级粗糙结构,该结构协同低表面能物质共同决定超疏水性木材的成功制得。此外,进一步研究了超疏水性木材表面的稳定性和耐久性。结果表明,该超疏水性木材于水、腐蚀性液体(酸液/碱液)、常见有机溶剂中以及一些常见条件下仍保留超疏水特性,为未来木材材料的应用领域扩展提供了有利条件。     

Imparting Superhydrophobicity with a Hierarchical Block Copolymer Coating

A robust and transparent silica‐like coating that imparts superhydrophobicity to a surface through its hierarchical multilevel self‐assembled structure is demonstrated. This approach involves iterative steps of spin‐coating, annealing, and etching of polystyrene‐block‐polydimethylsiloxane block copolymer thin films to form a tailored multilayer nanoscale topographic pattern with a water contact angle up to 155°. A model based on the hierarchical topography is developed to calculate the wetting angle and optimize the superhydrophobicity, in agreement with the experimental trends, and explaining superhydrophobicity arising through the combination of roughness at different lengthscales. Additionally, the mechanical robustness and optically passive properties of the resulting hydrophobic surfaces are demonstrated.     

Rapid fabrication of large-area, corrosion-resistant superhydrophobic Mg alloy surfaces

A superhydrophobic magnesium (Mg) alloy surface was successfully fabricated via a facile electrochemical machining process, and subsequently covered with a fluoroalkylsilane (FAS) film. The surface morphologies and chemical compositions were investigated using a scanning electron microscope (SEM) equipped with an energy-dispersive spectroscopy (EDS) and a Fourier-transform infrared spectrophotometer (FTIR). The results show hierarchal rough structures and an FAS film with a low surface energy on the Mg alloy surfaces, which confers good superhydrophobicity with a water contact angle of 165.2° and a water tilting angle of approximately 2°. The processing conditions, such as the processing time and removal rate per unit area at a constant removal mass per unit area, were investigated to determine their effects on the superhydrophobicity. Interestingly, when the removal mass per unit area is constant at approximately 11.10 mg/cm(2), the superhydrophobicity does not change with the removal rate per unit area. Therefore, a superhydrophobic Mg alloy surface can be rapidly fabricated based on this property. A large-area superhydrophobic Mg alloy surface was also fabricated for the first time using a small-area moving cathode. The corrosion resistance and durability of the superhydrophobic surfaces were also examined.     

Vi-PDMS/S-SiO2超疏水聚酯纤维织物的制备及性能研究

目的 基于普通织物材料防水性较差的问题,制备一种具有超疏水涂层的聚酯纤维织物,并对其性能进行研究。方法 以聚酯纤维织物为基材,基于紫外光固化技术通过浸涂法,使用商用气相纳米SiO₂颗粒(S-SiO₂)、端乙烯基聚二甲基硅氧烷(Vi-PDMS)在织物表面构筑微纳粗糙结构,获得超疏水的织物。采用扫描电子显微镜、水接触角测量仪对其微观结构和疏水性能进行表征,并通过机械摩擦实验对其超疏水稳定性进行考察。结果 当Vi-PDMS和S-SiO₂质量比为1∶4时,选择交联剂为三羟甲基丙烷三丙烯酸酯(TMPTA)制备的聚酯纤维织物表面的水接触角可达到151°,滚动角可达9°;且经过40次循环摩擦后,其表面水接触角仍大于140°,具有一定的耐磨性。结论 基于紫外光固化技术,采用操作简便的浸涂法制备的聚酯纤维织物具有优异的超疏水性能和一定的耐磨性,为织物超疏水性能研究提供参考,有望应用于超疏水聚酯纤维织物领域。     

通过粒子辅助水滴模板法制备超疏水材料

利用水滴模板法成功制备出孔径可控的具有结构规则的聚合物多孔膜,并以所制备多孔膜为模板利用反向复刻法复制孔洞阵列结构,得到具有微米级突起阵列结构的聚二甲基硅氧烷(PDMS)膜片,然后将事先排布好的二氧化硅微球阵列通过热压印法转移到具有微米级突起结构的PDMS膜片上,然后成功制备出具有微纳米复合突起结构的膜片。通过对具有不同突起结构组合的PDMS膜片进行接触角测试发现,膜片的接触角随着其表面粗糙程度的增大而增大,即具有微纳复合结构膜片接触角((150.7±3.2)°)最大,达到了超疏水的效果;无突起结构膜片的接触角((108.9±3.1)°)最小;而仅具有微米级结构膜片的接触角((134.6±1.0)°)居中,这符合目前已知的物质表面浸润性与其表面粗糙度的关系。另外,经测试,具有微纳复合结构的膜片接触角最大达到155°,同时具有非常大的滚动角,使得这种膜片材料具备了粘性超疏水的性能,而这种特殊浸润表面性质可以在液体无损传输、生化分离等领域拥有巨大的应用前景。     

Fabrication of ZnO submicrorod films with water repellency by surface etching and hydrophobic modification

Superhydrophobic ZnO submicrorod films have been fabricated on zinc sheets through an H₂O₂-assisted surface etching process and subsequent surface modification with a monolayer of 1H,1H,2H,2H-perfluorodecyltriethoxysilane (FDS). The crystal structure, chemical compositions, morphologies, and wettability of the resultant ZnO films were analyzed by means of X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and water contact angle measurements. It is found that the surface of the as-prepared ZnO films on zinc substrate was hydrophobic with a water contact angle of 95 ± 2°, whereas after modification with FDS, the film exhibited superhydrophobicity and the water CA increased to 154 ± 2°. It is shown that both the higher surface roughness and the lower surface free energy play an important role in creating the superhydrophobic films.     

Preparation of microstructure-controllable superhydrophobic polytetrafluoroethylene porous thin film by vacuum thermal-evaporation

The three-dimensional porous network polytetrafluoroethylene (PTFE) thin films were achieved by a vacuum technique through evaporating the pure PTFE powders. The surfaces of PTFE thin films showed various morphologies by adjusting the evaporation temperature and the corresponding contact angle ranging from 133° to 155°. Further analyses of surface chemical composition and morphology by FTIR and FE-SEM revealed that the origin of hydrophobicity for the PTFE thin films could be ascribed to the fluorine-containing groups and the surface morphologies, indicating that abundant -CF₂ groups and network structures with appropriate pore sizes played a vital role in superhydrophobicity. By characterization of UV-Vis, the films also showed high transmittance and antireflection effect. The films prepared by this simple method have potential applications such as waterproof membrane and self-cleaning coating.     

Superhydrophobic thin films with nanostructured surface prepared with Au nanoparticle masks

The hydrophobicity of a perfluoropolyether bisurethane methacrylate polymer film was investigated along with the formation of nano-hairs on its surface through reactive ion etching using gold nanoparticles (Au NPs) as masks. It was found that the hydrophobicity of the polymer film was strongly dependent on the number density of the nano-hairs which was determined by that of the Au NPs. The superhydrophobic surface was obtained when the number density was higher than 250 microm(-2). The effects of surface functionalization, Au NP immobilization, and etching time on the hydrophobicity of the polymer film were also examined extensively and discussed based on the results of the contact angle measurements and the scanning electron microscopy.     

Inspired superhydrophobic surfaces by a double-metal-assisted chemical etching route

Silicon substrates treated by metal-assisted chemical etching have been studied for many years since they could be employed in a variety of electronic and optical devices such as integrated circuits, photovoltaics, sensors and detectors. However, to the best of our knowledge, the chemical etching treatment on the same silicon substrate with the assistance of two or more kinds of metals has not been reported. In this paper, we mainly focus on the etching time and finally obtain a series of superhydrophobic silicon surfaces with novel etching structures through two successive etching processes of Cu-assisted and Ag-assisted chemical etching. It is shown that large-scale homogeneous but locally irregular wire-like structures are obtained, and the superhydrophobic surfaces with low hysteresis are prepared after the modifications with low surface energy materials. It is worth noting that the final silicon substrates not only possess high static contact angle and low hysteresis angle, but also show a black color, indicating that the superhydrophobic silicon substrate has an extremely low reflectance in a certain range of wavelengths. In our future work, we will go a step further to discuss the effect of temperature, the size of Cu nanoparticles and solution concentration on the final topography and superhydrophobicity.     

Differential superhydrophobicity and hydrophilicity on a thin cellulose layer

Here we have developed cellulosic materials (cotton fabric or paper) with differential superhydrophobicity and hydrophilicity on each side of the surfaces by coating with polyvinylidene fluoride and fluorinated silane molecules using electro-spraying. Such materials are advantageous in various textile and medical applications.Analysis of surface morphology indicated that, not only surface chemical property and roughness, but also particle diameter affects surface superhydrophobicity. Smaller particle diameter enhances superhydrophobicity, if the surface roughness and surface chemical property remain constant. By controlling these three factors, superhydrophobicity with a water contact angle of more than 160° can be achieved at one side of a thin cellulosic material while maintaining the hydrophilicity (contact angle is 0°) at the opposite side.     

2A12铝合金基体超疏水表面制备及性能研究

铝合金在使用过程中极易引发基体腐蚀现象,如点蚀、晶间腐蚀等,为保障铝合金在腐蚀环境中的应用,可通过建立超疏水表面改变铝合金表面的润湿性,从而在一定程度上减少腐蚀液与铝合金表面的接触,进而改善耐蚀性。本文通过酸刻蚀和沸水刻蚀两种方法在铝合金表面构筑微纳米结构,并使用低表面能物质硬脂酸进行表面处理得到超疏水表面。采用扫描电子显微镜、接触角测试仪、原子力显微镜分别对铝合金表面形貌、疏水性和粗糙度进行测试,得到两种方法的最佳制备时间,而后通过极化曲线对两种方法制备的铝合金表面耐蚀性能进行对比,进而研究两种刻蚀方法对铝合金耐蚀性的影响。实验结果表明：酸刻蚀时间为15 s时,铝合金表面接触角达到峰值163.9°,呈现超疏水状态,相对于空白样品,表面粗糙度增加了24倍,电化学自腐蚀电位正向移动0.362 8 V;沸水刻蚀时间为1 min时,其表面接触角达到峰值109.6°,比空白样品疏水性强但未呈现超疏水状态,相对于空白样品,经沸水刻蚀的铝合金表面粗糙度增加了4.4倍,电化学自腐蚀电位正向移动0.074 8 V。两种方法处理得到的铝合金表面的耐蚀性与空白铝合金试样相比均有显著提高,而酸刻蚀法的缓蚀效...