耐腐蚀超疏水超亲油不锈钢网的制备及其在油水分离过程中的应用

以不锈钢网为基底,通过化学刻蚀法制备微米级粗糙表面,通过一步浸泡法将st9ber法制得的疏水亲油纳米Si O2颗粒沉积到粗糙的不锈钢网表面,制备了具有微纳二级粗糙结构的超疏水超亲油不锈钢网。利用扫描电子显微镜(SEM)、傅里叶变换红外光谱仪(FT-IR)和接触角测量仪(CA)表征了超疏水超亲油不锈钢网的表面形貌、化学组成和润湿性能,并将其用于油水分离过程中。结果表明,疏水亲油纳米Si O2颗粒成功的沉积到不锈钢网表面;水滴在超疏水超亲油不锈钢网上的接触角最大为151°,煤油的接触角为0°;制备的超疏水超亲油不锈钢网不仅能高效的分离不同种类油和水的混合物,还能高效的分离油和腐蚀性液体(强酸或强碱水溶液)的混合物,其耐腐蚀特性可满足复杂环境下的油水分离要求。     

ZnO nanorod array-coated mesh film for the separation of water and oil

Dense and vertically aligned ZnO nanorod arrays with a large area have been fabricated successfully on the stainless steel mesh by a simple chemical vapor deposition method. The coated mesh exhibited both superoleophilic and superhydrophobic properties, even if it was not modified by low surface energy materials. The separation efficiencies were more than 97% in the filtration of water and oil. Besides, the wettability of the coated mesh was still stable after it was soaked in the corrosive solutions for 1 h. A detailed investigation showed that the coated mesh has the best superhydrophobic property when the stainless steel mesh pore size was about 75 μm.     

A robust and coarse surface mesh modified by interpenetrating polymer network hydrogel for oil‐water separation

A robust and coarse surface mesh was fabricated by introducing a hydrogel coating with interpenetrating polymer network (IPN) structure on stainless steel mesh. The IPN hydrogel was prepared by crosslinking polymerization of acrylic acid (AA) followed by condensation reaction of polyvinyl alcohol (PVA) and glutaraldehyde (GA) at room temperature. As a result, the roughness of modified mesh was enhanced obviously and oil droplet underwater showed a larger contact angle. The hydrogel‐coated surface showed an underwater superoleophobicity with an oil contact angle of 153.92 ± 1.08^°. Besides, stable wettability was observed. The mesh can selectively separate oil from water with a high separation efficiency of above 99.8%. This work provides a facile method to strengthen the coating and enhance the efficiency of oil‐water separation. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41949.     

Fabrication of superhydrophobic unplasticized poly(vinyl chloride)/nanosilica sheets using Taguchi design methodology

This study introduces a relatively simple technique for the manufacture of superhydrophobic coatings on polymeric surfaces. Plastics such as unplasticized poly(vinyl chloride) (UPVC ) do not have a strong hydrophobic nature that is characterized by their low contact angles. Techniques of both increasing surface roughness and lowering surface energy are required to change their hydrophilicity to superhydrophobicity. In the present study, a coating of a low‐surface‐energy thermoplastic polyurethane (TPU ) was spin‐coated with chemically treated nanosilica to reduce the surface energy of UPVC . Nanosilica particles were embedded on the surface using a hot‐press. Taguchi design was used to optimize multiple processing parameters. Samples spin‐coated with 10 g L^?1 nanosilica suspension in ethanol at a rate of 400 rpm for 5 s and then hot‐pressed at 155 °C under 2 atm (203 kPa ) for 4 min had a contact angle of ca 157° and sliding angle of ca 6°, which are characteristic of superhydrophobic surfaces. Atomic force microscopy (AFM) and scanning electron microscopy (SEM ) imaging showed that these superhydrophobic surfaces were highly rough with nanoscale features. Peel test and SEM analysis showed that silica nanoparticles embedded in the TPU coating were more stable than particles immobilized on UPVC sheet without TPU coating, proving that a layer of more flexible coating can improve the longevity of superhydrophobic surfaces manufactured using this facile method. © 2016 Society of Chemical Industry     

氟化SiO2纳米颗粒双疏涂层的制备及性能研究

采用氟化硅烷偶联剂对合成的单分散SiO2纳米颗粒进行表面接枝改性,并通过旋涂法将制备的氟化SiO2颗粒沉积在硅晶基板上.采用粒径分析仪、傅里叶变换红外光谱仪(FTIR)、热重分析仪(TG-DTA)、扫描电镜(SEM)和接触角测量仪对氟化SiO2纳米颗粒涂层的表面形貌、化学组成、接枝密度和润湿性能进行分析表征.结果表明:氟化硅烷偶联剂在SiO2纳米颗粒表面的接枝密度为5.94 nm-2;制备的氟化SiO2纳米颗粒薄膜具备微纳米双重复合网络结构,增加了涂层表面的粗糙程度;氟化SiO2纳米颗粒涂层展现出超疏水和强疏油性能,水和柴油在氟化SiO2纳米颗粒薄膜上的接触角分别为158.4°和125.7°.     

A novel composite coating mesh film for oil-water separation

Polytetrafluoroethylene-polyphenylene sulfide composite coating mesh film was successfully prepared by a simple layered transitional spray-plasticizing method on a stainless steel mesh. It shows super-hydrophobic and super-oleophilic properties. The contact angle of this mesh film is 156.3° for water, and close to 0° for diesel oil and kerosene. The contact angle hysteresis of water on the mesh film is 4.3°. The adhesive force between the film and substrate is grade 0, the flexibility is 1 mm and the pencil hardness is 4H. An oil-water separation test was carried out for oil-contaminated water in a six-stage superhydrophobic film separator. The oil removal rate can reach about 99%.     

Electrochemical characterization of polythiophene-coated steel

In situ electropolymerization leading to polythiophene coating has been found to be a new option for providing corrosion protection to mild steel surface. The polythiophene coating thus coated has been diagnosed through polarization and AC impedance analysis, which has demonstrated the passivation role of conducting polythiophene coating. The determination of volume fraction, water uptake and delamination area have been used to further support the corrosion protection of conducting polythiophene coating.     

Transparent and durable SiO2‐containing superhydrophobic coatings on glass

We fabricated novel superhydrophobic coatings based on SiO₂ nanoparticles combined with NH₂‐terminated silicone (SN₂) or SN₂‐modified polyurethane (SN₂‐prePU) by alternately spin‐coating them onto glass slides. The final fabricated surface contained SN₂/SiO₂ or SN₂‐prePU/SiO₂ bilayers. The conditions of spin‐coating method were also explored. SN₂‐prePU with different SN₂/prePU molar ratios were synthesized to study the influence of SN₂ ratio on the water contact angles of ultimate spin‐coated surfaces. The surface was found to be tunable from hydrophobic to superhydrophobic by choosing SN₂‐prePU with different SN₂/prePU molar ratios or SN₂ content. Water droplets easily rolled off on these superhydrophobic surfaces. Surfaces coated with SN₂/SiO₂ bilayers showed better transparency, whereas surfaces coated with SN₂‐prePU(2 : 1)/SiO₂ bilayers exhibited better durability. Droplets of varied pH were prepared to test the anti‐wettability of the coatings. Results showed that the as‐coated surfaces had stable superhydrophobicity to droplets with pH values ranging from 1 to 14. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41500.     

Novel superhydrophobic top coating on surface modified PVC-coated fabric

A superhydrophobic surface was created on poly(vinylchloride)-coated architectural fabric using spray coating method. Dispersions of nanoparticles and a flourochemical were prepared as top coating solutions. After spray-dry-cure process, contact angle, sliding (tilt) angle, 3 M water repellency test and surface morphology were compared between uncoated and top coated PVC surfaces. The results indicated that a specific nano-TiO₂ dispersion top coating produced a superhydrophobic layer on the top of the PVC surface with high contact angle (150°) and very low sliding angle (2°). Combination of two major requirements, the magnified of the degree of roughness and low surface energy, created self-cleaning effect on the PVC surface. Abrasion fastness of superhydrophobic top coating was improved by surface oxidation via UV–ozone surface treatments. Spectroscopic analysis demonstrated that formation of oxygenated functional groups has improved PVC wettability and adhesion. Results of artificial weathering test indicated no change in superhydrophobicity of top coated PVC.     

Structure and properties of regenerated cellulose films coated with polyurethane–nitrolignin graft‐IPNs coating

A regenerated cellulose film (RC) was coated with a graft‐IPNs coating, which was composed of castor oil‐based polyurethane and 2.8 wt % nitrolignin (NL), to obtain water‐resistant films. The effects of NCO/OH molar ratio and different polyols, such as 1,4‐butanediol (BDO) and trimethanol propane (TMP), on the structure and properties of the coated RC films were investigated. With an increase of the NCO/OH molar ratio, the tensile strength of the coated films increased, but the water resistivity and size contraction hardly changed. The coated films with TMP exhibited the higher breaking elongation at 1.5 of the NCO/OH molar ratio, while those with BDO have more excellent tensile strength, water resistivity, and dimensional stability. The coated films with the graft‐IPNs coating exhibited superior water resistivity and dimensional stability. The light transmittance of the coated films was more excellent than that of the RC film. Moreover, the results from the IR and electron probe microanalysis (EPMA) showed that the chemical bonding occurred between cellulose and coating, and the introduction of NL plays an important role in the enhancement of the interface adhesion of the coated films. Atomic force microscopy (AFM) depicted the flat and dense surface of the coated films, which restricted the water vapor penetration and the size contraction, resulting in the enhancement of water resistivity. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1799–1806, 2002     

Facile and eco-friendly fabrication of hierarchical superhydrophobic coating from eggshell biowaste

This study reports a facile and sustainable approach to fabricate superhydrophobic coating from eggshell biowaste. The coating was prepared by ball milling chicken eggshells, composed of hydrophilic calcium carbonate (CaCO₃), to microsized particles followed by surface hydrophobilizing with stearic acid (C₁₇H₃₅COOH) to form low surface energy nanosized calcium stearate ((C₁₇H₃₅COO)₂Ca) through the esterification of hydroxyl groups (-OH) absorbed on a surface of CaCO₃ with carboxyl groups (–COOH) of stearic acid. Then, a layer of modified eggshell particles dispersed in polystyrene (PS) binder was dip-coated on a substrate. A coated surface with water contact angles of 151° ± 1° on glass and 153° ± 1° on cotton fabric substrates was achieved when a 4:1 weight ratio of the modified eggshell:PS was used. The uniform distribution of the modified eggshell particles throughout the coating led to a surface with high degree of hierarchical micro-nanoscale roughness which resulted in superhydrophobicity. The superhydrophobic eggshell coating showed good environmental stability, self-cleaning, and oil/water separation properties. These results suggest that eggshell biowaste can be utilized for superhydrophobic applications.     

MCT Oil Coating Improves the Oxidative Stability of Surface Lipids in Corn Extrudates

Lipid‐containing extrudates are highly susceptible to lipid oxidation because of their porous structure and high specific surface area. The objective of this study is to investigate the effect of a low‐oxidizable medium‐chain triglycerides (MCT) coating on the oxidative stability. Therefore, cornmeal is extrusion cooked with commercial vegetable oil and various water contents (10–18% on dry matter) and partially coated with 5% w/w MCT oil. Lipid oxidation in the extrudates is examined during storage at +40 °C by measuring hydroperoxide concentrations in different lipid fractions (surface, inner‐surface, and matrix‐incorporated lipids). Hexanal is analyzed using headspace‐gas chromatography. Coating allocation is studied by fatty acid profiles of the lipid fractions, by fluorescence microscopy, and computerized microtomography. Application of an MCT coating leads to lower hydroperoxide concentrations and significantly reduces hexanal formation during storage. In particular, the surface lipids are stabilized. MCT oil diffuse only to small extent inside the extrudates and its effect on lipid oxidation can be attributed to differenct effects: filling surface microcracks, reducing the release of volatiles, and dilution of oxidizable lipids. This effect is strongest in porous extrudates with low feed‐water content. Practical applications: Inhibition of lipid oxidation of fatty extrudates is of great importance for producers as well as consumers. In this study, we examine whether it is possible to improve the oxidative stability of extrudates by application of a lipid‐based coating. The results of this study suggest that it will be possible in the future to produce extrudates that are protected from oxidation by a thin natural oil film. We expect that especially products such as kibbles could benefit from treatment with a low‐oxidizable lipid‐based coating. In these products, fats are already used in combination with other functional ingredients. The combination of an MCT coating with a palatant or antioxidant is, therefore, an obvious alternative and of high relevance for manufacturers.     

Three‐dimensionally printed bioinspired superhydrophobic PLA membrane for oil‐water separation

A novel lotus‐leaf‐inspired superhydrophobic poly(lactic acid) (PLA) porous membrane was fabricated for oil‐water separation based on fused deposition modeling three‐dimensional printing and subsequent chemical etching and the decoration of polystyrene nanospheres. A superhydrophobic PLA fractal surface with a water contact angle of 151.7° and low water adhesion force of 21.8 μN was achieved. The membrane pore size could be easily adjusted from 40 to 600 μm via a computer‐aided design program to optimize separation performance. The maximal oil‐water separation efficiency of 99.4% was achieved with a pore size of 250 μm, which also exhibited a high flux of 60 kL m^?2 h^?1. © 2018 American Institute of Chemical Engineers AIChE J, 64: 3700–3708, 2018     

聚芴醚酮超疏水喷涂纸及其性能

以聚二甲基硅氧烷(PDMS)和纳米SiO2掺杂聚芴醚酮(PFEK),采用溶液喷涂法在纸张表面构筑了耐用的超疏水涂层.考察了PDMS和SiO2用量(以PFEK和N-甲基吡咯烷酮的质量为基准,下同)对纸张水接触角的影响.结果表明,当PDMS和SiO2用量均为2％时,纸张表面的水接触角达到最大值170?,滚动角最小值为1?,...     

Fabrication of flower clusters-like superhydrophobic surface via a UV curable coating of ODA and V-PDMS

In this work, a flower clusters-like superhydrophobic surface was fabricated via an ultraviolet (UV) curable coating of octadecylamine (ODA) and vinyl-terminated polydimethylsiloxane (V-PDMS). ODA self-assembled into many flower clusters-like structures on the surface of the coating, increasing the roughness of the coating surface without additional nanoparticles. V-PDMS formed a highly crosslinked network under a UV lamp, which would be helpful for a robust superhydrophobic surface. The obtained PDMS/ODA fabric showed water contact angle of 161° and sliding angle of 5°. The durability of the superhydrophobic surface was tested by water impacting, tube brush scrubbing, knife scratching, hand twisting, finger pressing, tape adhesion, abrasion, continuous rinsing, and chemical conditions. The experimental results indicated that the superhydrophobic surface have good durability for long service life. Moreover, the PDMS/ODA fabric could selectively absorb oils from water with good separation performance. This work will provide a facile, low cost, and versatile method to prepare superhydrophobic surfaces, and enhance their efficiency of oil–water separation. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48210.     

Preparation and anti‐icing property of a lotus‐leaf‐like superhydrophobic low‐density polyethylene coating with low sliding angle

A lotus‐leaf‐like superhydrophobic low‐density polyethylene (LDPE) coating with low sliding angle was prepared by a facile method. The water contact angle and sliding angle of the as‐prepared superhydrophobic LDPE coating were 156 ± 1.7° and 1°, respectively. The anti‐icing property of the as‐prepared LDPE coating with low sliding angle was investigated in a climatic chamber with a working temperature of ?5°C. The results showed that the superhydrophobic LDPE coating with low sliding angle can largely prevent ice formation on the surface, showing excellent anti‐icing property. The as‐prepared superhydrophobic LDPE coating with good anti‐icing property will be perfectly desirable for outdoor equipments to reduce ice formation on their surfaces in cold seasons. This work will provide a new way to fabricate anti‐icing coating and thus find applications in a variety of fields. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers     

One‐Pot Route for Fe@Poly(styrene‐co‐divinylbenzene) Foam with Robust Physical/Chemical Stability and Remote Magnetic Driven Capacity for Oil Removal

Magnetic and superhydrophobic materials with robust physical/chemical stability for controllable and remote magnetic driven capacity for oil removal under harsh environments are meaningful for oil–water separation but still a challenge. Herein, an alternative strategy to address this challenge is demonstrated by decorating poly(styrene‐co‐divinylbenzene) (PSDVB) on Fe foam via one‐pot solvothermal method. Different from previous magnetic and superhydrophobic materials, Fe foam is chosen to replace Fe₃O₄ nanomaterials. Thus, complicated preparation procedures and the high cost for Fe₃O₄ nanomaterials can be avoided. Additionally, PSDVB coating provides the whole foam with robust physical/chemical stabilities: i) the surface wettability can be maintained after 50 abrasion cycles or exposed in humid air (relative humidity: 90%) for 14 days, and ii) the surface wettability does not change under different pH solutions (3 < pH < 12) or highly salty solution (NaCl 10 wt%) for 6 h. Besides, outstanding separation efficiency (>99.9%), high durability (>70 times), and excellent oil flux (16 963–75 156 L m^?2 h^?1) can be realized under gravity. Most importantly, the foam continuously removes oil from confine place (on water surface or under water) under magnetic driven force.     

A hierarchical mesh film with superhydrophobic and superoleophilic properties for oil and water separation

BACKGROUND: Solid surfaces possessing both superhydrophobic and superoleophilic properties have attracted great interest for fundamental research and potential application. However, fabrication of the reported surfaces is usually time‐consuming and the wetability of the surfaces could not be achieved to the desired level in rugged environments. RESULTS: A hierarchical stainless steel mesh film comprising structures with three scales of roughness was synthesized by a simple chemical bath deposition method. After being modified with a low surface energy material e.g. Teflon, these films exhibit superhydrophobic and superoleophilic properties. In this study it was demonstrated that the unique properties of the as‐prepared films match well with the requirements for the effective separation of oil and water mixtures. CONCLUSION: It was confirmed that the unique surface wetability of the surface is due to the cooperative effect of the hierarchical structures of the stainless steel mesh films and the natural low surface tension of Teflon. Furthermore, fabrication is simple and economic, and the surface exhibited robust durability even in a rugged environment. Copyright © 2011 Society of Chemical Industry     

Facile synthesis of superhydrophobic surface of ZnO nanoflakes: chemical coating and UV-induced wettability conversion

This work reports an oriented growth process of two-dimensional (2D) ZnO nanoflakes on aluminum substrate through a low temperature hydrothermal technique and proposes the preliminary growth mechanism. A bionic superhydrophobic surface with excellent corrosion protection over a wide pH range in both acidic and alkaline solutions was constructed by a chemical coating treatment with stearic acid (SA) molecules on ZnO nanoflakes. It is found that the superhydrophobic surface of ZnO nanoflake arrays shows a maximum water contact angle (CA) of 157° and a low sliding angle of 8°, and it can be reversibly switched to its initial superhydrophilic state under ultraviolet (UV) irradiation, which is due to the UV-induced decomposition of the coated SA molecules. This study is significant for simple and inexpensive building of large-scale 2D ZnO nanoflake arrays with special wettability which can extend the applications of ZnO films to many other important fields.     

Preparation of super‐hydrophobic film with fluorinated‐copolymer

Organic superhydrophobic films were prepared by utilizing TA‐N fluoroalkylate (TAN) and methyl methacrylate (MMA) copolymer as water‐repellent materials and inorganic silica powder as surface roughness material has been developed. Coating solutions prepared by adding silica powders into copolymer solution directly (one‐step method) and by adding silica powders into monomers and allowing them to react (two‐step method). The results showed that contact angles of the films prepared by one‐step method (37.6 wt % of silica powders in the coating solution) were greater than 150°, but the transmittance of the film at visible light was only 30%. On the other hand, the contact angle of films prepared by two‐step method (20 wt % of silica powders in the coating solution) was greater than 160° and the transmittance of the film was greater than 90%. The contact angle of the film prepared by poly(octyl acrylate), POA, was 32.1°, but while introducing silica powder into the system, the contact angle of the film was reduced to be smaller than 5°. Thus, superhydrophobic and superhydrophilic films can be obtained by introducing a roughening material on the hydrophobic surface and the hydrophilic surface, respectively. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1646–1653, 2007