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The development of hydrophobic and oleophobic surfaces on materials has attracted significant attention in various research fields. Fluoropolymers, which possess low surface energy and are both highly hydrophobic and oleophobic in nature, are widely used to enhance the liquid repellency of materials. However, during fluoropolymer manufacture, fluorine‐containing compounds are released into the environment; thus, alternatives to fluoropolymers are required for maintaining environmental safety and realizing a sustainable society. Notably, the development of such alternative materials has been limited. Thus, we herein report the application of a novel polyurethane (PU) coating synthesized from bio‐based raw materials. The prepared hydrogenated polyfarnesene PU (HHPF PU), which possesses an amorphous bottlebrush‐like polyalkyl structure, was found to exhibit higher hydrophobicity and oleophobicity than polytetrafluoroethylene (PTFE), which is a typical low‐surface‐energy material. The water and n‐hexadecane contact angles of the HHPF PU were determined to be 119° and 68°, respectively, whereas those of PTFE were 108° and 46°, respectively. In addition, the density depth profile of the PU thin film was confirmed through x‐ray reflectometry. This study provides a novel approach for enhancing the hydrophobicity and oleophobicity of materials using bottlebrush‐like polyalkyl structure instead of fluorine. [ABSTRACT FROM AUTHOR]

A novel castor oil-based polyols with fluorine-containing pendant groups (CO-FPOL) has been synthesized through ring-opening polymerization from castor oil (CO), propylene oxide (PO) and self-made 3-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluoro-octyloxymethyl)-Oxirane (TDFOMO). The TDFOMO was synthesized from 3,3,4,4,5,5,6,6,7,7,8,8,8-Tridecafluoro-1-octanol (TDFOL) and Epichlorohydrin (ECH). Then, the CO-FPOLs further reacted with a 4,4′-diphenylmethane diisocyanate (MDI) to prepare a one-component fluorinated polyurethane coating (CO-FPUP). Strikingly, the fluorine content of CO-FPOL can be easily controlled, the thermal stability of CO-FPOL and CO-FPUP increased with the increasing of fluorine content. It was all found that with the fluorine content of CO-FPOL increasing from 0% to 17.72%, the static water contact angle of CO-FPUPs increased from 90° to 106°, and the static oil contact angle of CO-FPUPs increased from 20° to 54°. The XPS survey spectra revealed that the fluorine in the cured polyurethane would migrate to the surface easier due to the fluorinated pendant groups which moving easier between molecular chains. All the above results suggest that the introduction of fluorinated pendant groups in polyether polyol has great improvements in the thermal stability and the hydrophobic and oleophobic properties of polymer materials. [ABSTRACT FROM AUTHOR]

Superhydrophilic/oleophobic materials are considered to be the best materials for achieving oil‐water separation, but their preparation is difficult and the existing methods are not universal. In this paper, a two‐step modification strategy was used to prepare superhydrophilic/oleophobic sponges by adjusting the polar and nonpolar components of the materials using mussel‐inspired chemistry. While remaining superhydrophilic, the modified sponge surface has a maximum contact angle of 135° with different oils in air. The modified sponge exhibited superoleophobicity in water, and the contact angle of oil could reach more than 150°. In addition, the modified sponges were also reusable, chemically stable, and mechanically durable. Its oil‐water separation flux was up to 24900 Lm−2 h−1 bar−1, and the separation efficiency was above 97 %. We believe that this method will provide an environmentally friendly and efficient way to prepare the superhydrophilic/oleophobic materials. [ABSTRACT FROM AUTHOR]

Super-hydrophilic and oleophobic functional materials can prevent pollution or adsorption by repelling oil, and have good circulation. However, traditional strategies for preparing these functional materials either use expensive fabrication machines or contain possibly toxic organic polymers, which may prohibit the practical application. The research of multifunctional ZnO microstructures or nanoarrays thin films with super-hydrophilic, antifouling, and antibacterial properties has not been reported yet. Moreover, the exploration of underwater oleophobic and self-cleaning antifouling properties in ZnO micro/nanostructures is still in its infancy. Here, we prepared ZnO microstructured films on fluorine-doped tin oxide substrates (F-ZMF) for the development of advanced self-cleaning type super-hydrophilic and oleophobic materials. With the increase of the accelerators, the average size of the F-ZMF microstructures decreased. The F-ZMF shows excellent self-cleaning performance and hydrophilic (water contact angle ≤ 10°) and oleophobic characteristics in the underwater antifouling experiment. Under a dark condition, F-ZMF-4 showed good antibacterial effects against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) with inhibition rates of 99.1% and 99.9%, respectively. This study broadens the application scope of ZnO-based material and provides a novel prospect for the development of self-cleaning super-hydrophilic and oleophobic materials. [ABSTRACT FROM AUTHOR]

We demonstrate in this paper a super-hydrophilic and oleophobic green porous photothermal material based on wood fiber as a novel oil-repellent photothermal material for efficient solar vapor generation (WF-SP). WF-SP is an excellent light-absorbing material with the advantages of a porous nanostructure, super-hydrophilic, low thermal conductivity, high-temperature resistance, and oleophobicity. Based on these advantages, WF-SP exhibits good solar photothermal conversion performance with solar vapor generation efficiencies of 85.4%, 75.3%, and 70.2% at 1 kW m−2, 2 kW m−2, and 3 kW m−2 radiation intensities, respectively. The results provide new possibilities for the design and preparation of low-cost, green, and pollution-free photothermal materials with high solar thermal conversion efficiency for solar photothermal conversion vapor generation. [ABSTRACT FROM AUTHOR]

Polytetrafluoroethylene (PTFE) nano-porous membrane has been widely used in various fields due to its excellent thermal stability and chemical stability. However, PTFE nanofiber membranes with simultaneous hydrophobic and oleophobic properties are essential to promote the application of PTFE. Here, based on inorganic/organic nanohybridization, we report a strategy for constructing nanostructures on fibers by adding nanoparticles, such as MOF and ZrO2. The results of FTIR and XRD confirmed MOF was synthesized successfully. At the same time, the SEM results showed UiO-66-(COOH)2 is spherical with an average diameter of 152 nm, and there is no agglomeration, which is suitable for electrospinning. Further, MOF and ZrO2 were payload into PTFE nanofibers. The results of SEM and AFM confirmed nanostructures will be more uniform and pronounced with the increase of UiO-66-(COOH)2 content, and nanostructures are most obvious when the content of UiO-66-(COOH)2 is 15%. The introduced nanostructures can increase the oil contact angle of the PTFE nano-porous membrane to 110° without introducing other groups, and further improve the water contact angle from 133° to 145°. Meanwhile, the introduction of a certain amount of hydrophilia groups can increase the oil contact angle to more than 120°. The simple strategy is of great significance to expand the application of PTFE fiber membrane in dealing with waste water treatment fields. [ABSTRACT FROM AUTHOR]

Biological systems with special wettability have attracted significant interest as superwetting surfaces. Recently, there has been a growing interest in unusual oleophobic/hydrophilic surfaces that exhibit high oil contact angle (OCA) and low water contact angle (WCA). Although these surfaces demonstrate potential applications in water/oil separation, detergent-free cleaning, and oil-repellent anti-fogging, their fabrication is challenging because of the lower surface tension of oil than that of water. In this study, we prepared layer-by-layer (LbL) films consist of Nafion (NAF), branched polyethyleneimine (PEI), and SiO2 nanoparticles, and studied the effect of the LbL assembly condition on film growth and water/oil wettability. Typical WCA and OCA values of NAF/PEI film were ~128° and ~21°, respectively. The WCA and OCA changed as the SiO2 nanoparticles were added and the films were treated with perfluorooctane sulfonate. When the WCA and OCA difference was the smallest, the WCA and OCA values of the NAF/PEI/ SiO2 film were 121° and 91°, respectively. Furthermore, we prepared two-layer LbL films by coating NAF/PEI/SiO2 films onto porous LbL films. As the PFOS-terminated NAF/PEI/SiO2 film were deposited, the WCA decreased from 119 to 78°, and the OCA was fairly constant at 108°, showing a reversal of the WCA and OCA values. We expect that this study will provide a better understanding of the fabrication of LbL-assembled oleophobic/hydrophilic surface. [ABSTRACT FROM AUTHOR]

Marble kitchen countertops and other natural stone surfaces are often stained by various food ingredients and contaminants during daily use and require frequent cleaning, which is time-consuming and leads to the wasting of water. If the surface is coated with a hydrophobic and oleophobic coating, food ingredient contamination becomes easier to wipe clean. Therefore, a UV-curable monomer with fluorocarbon branched chains was synthesized and added to UV-curable coatings in different ratios. The preferred formulation that meets the basic performance requirements of UV-curable coatings, and has the best hydrophobic and oleophobic properties, was designed and selected. The formulation was upgraded by adding a hydrofluoric ether (HFE) solvent. These upgraded formulations were tested for hydrophobicity and oleophobicity under various conditions. The addition of an HFE solvent improves the initial water and cetane contact angles of the paint film, as well as the water and cetane contact angles under various conditions. Moreover, the upgraded formulations have better stain resistance. The degree of hydrophobicity and oleophobicity improvement is positively correlated with the addition of an HFE solvent. The UV-curable fluorocarbon polyurethane coating has good adhesion on a marble surface that has been polished and primed. Due to the presence of TEOH-6 instead of PFOA, the low content of fluorocarbon functional groups effectively located on the film surface makes the coating quite stable and safe. [ABSTRACT FROM AUTHOR]

The competition among sheet-metal-forming manufacturers in recent years has become more severe. Many manufacturers have survived by cutting their production costs. Increasing the formability, which could reduce the production costs, is the focus of many manufacturers and engineers. In the present research, to increase the formability over the limiting drawing ratio (LDR) in the cylindrical deep-drawing process, the application of oleophobic coating is proposed. An SUS304 (JIS standard)-stainless-steel cylindrical deep-drawn component was used as the investigated model. First, we applied the oleophobic coating in the sheet-metal-forming process, and tribology tests were carried out to examine the friction coefficients, which were reduced by approximately 60% compared with those of standard lubricant use (Iloform TDN81). Next, deep-drawing tests were performed to investigate the drawing ratio (DR). The LDR recommended in the past could be overcome, and it increased by approximately 12% with the oleophobic coating use. Finally, the deep-drawing mechanism using an extremely low friction coefficient was clarified as well. Based on these results, an oleophobic coating could be applied in the cylindrical deep-drawing process to increase the LDR. The results also clearly expose the multidisciplinary approach that combines an oleophobic coating application and the sheet-metal-forming process. [ABSTRACT FROM AUTHOR]

As a functional decorative material on the surface of printing and packaging, coating plays the role of increasing gloss, wear resistance, and antifouling. It has broad application prospects in high-end printed materials such as posters, art reproductions, and maps. In this paper, dodecafluoroheptyl methacrylate was used as the fluorine-containing monomer, which was used to modify the epoxy resin and introduce fluoride first. Under the action of polymerization inhibitor and catalyst, the epoxy resin was further modified by ring opening, esterification, and neutralization with acrylic acid, maleic anhydride, and organic base as raw materials. Additionally, a fluorine-containing coating with hydrophobic and oleophobic properties was obtained finally. The effects of fluorine modification of epoxy resin and synthetic polymer were characterized by infrared spectrometer and photoelectron spectroscopy. The results showed that fluorine monomer could be successfully grafted to the molecular body of epoxy resin, and fluorine had been introduced into the surface of the polymer film. Using the contact angle tester, combined with the performance parameters such as grafting rate, thermal stability, adhesion, and gloss, the effects of the amount of fluorine monomer on the properties of the synthetic coating were discussed. The results showed that the hydrophobic and oleophobic properties of the copolymer film surface were closely related to the amount of fluorine monomer. When the molar ratio of the epoxy group to dodecafluoroheptyl methacrylate was 26:1, the mass fraction of fluorine on the film surface was 18.09%, and the contact angles of water and ethylene glycol were 121.8° and 78.2° respectively. At the same time, the printability of self-made hydrophobic and oleophobic coating was tested in this paper. The liquid repellency of inkjet printing before and after glazing and the influence of the coating on the optical properties of printed images were discussed and studied too. The results showed that the coating synthesized by the experiment was suitable for inkjet printing. It had improved the printing quality performance and the functional modification on the surface of inkjet printings, such as liquid repellency, gloss, and color reproduction. [ABSTRACT FROM AUTHOR]

It is crucial to enhance the concrete permeation resistance to liquefied natural gas (LNG) by utilizing a functional coating having excellent cryogenic stability. In this study, a novel method was provided to prepare a modified nanosilica-resin composite coating with excellent oleophobicity and permeation resistance to small molecule alkane oils. The properties of this coating were comprehensively characterized in terms of wettability test, mechanical stability test, chemical stability test, and oil impermeability test. Additionally, its cryogenic stability was also evaluated through the above methodologies. The results showed that the contact angle of mineral oil on the coating exceeds 150°, with a contact angle loss rate of only 2.98 % after 100 cycles of sandpaper abrasion. The contact angle remained above 130° after 24-h immersion in HCl, NaOH, and NaCl solutions, indicating its excellent chemical stability. Upon application, the coating significantly reduces the oil absorption rate of concrete exposed to small-molecule alkane oil by >80 %. More significantly, the contact angle of the coating remained above 150° even after cryogenic treatment, exhibiting a minimal contact angle loss rate of just 2.77 % following 100 cycles of sandpaper abrasion, demonstrating excellent cryogenic stability. The scanning electron microscope and X-ray photoelectron spectrometer results showed that the coating can maintain micro-nano rough structure and chemical structure of fluorine-containing low surface energy functional groups after cryogenic treatment, attributing to its remarkable stability. These findings underscore the novel coating's substantial potential for application potential in various cryogenic industrial fields. • A novel modified nanosilica-resin composite coating was prepared. • The coating exhibits "double impermeability" effect to small molecule alkane oil. • The coating shows excellent resistance to cryogenic condition exposure. [ABSTRACT FROM AUTHOR]

Solar interfacial evaporation based oil/water separation using wood-melamine/calcium alginate composite with black cotton. [Display omitted] • An effective solar interfacial evaporator is designed for oi/water separation. • A hydrophilic-oleophobic wood-melamine/calcium alginate composite is designed. • A water evaporation rate of 5.74 kg•m−2•h−1 is obtained under 5 solar suns. • Oil volume fraction of condensed water is significantly less than 0.2%. Solar interfacial evaporation is an attractive phenomenon for water treatment using renewable energy without further environmental contamination. However, the existing researches mainly focus on improving water evaporation rate with diversified interfacial and porous materials for solar absorption and water transport. The oil/water separation from emulsion under solar interfacial evaporation is rarely investigated. Under these circumstances, a wood-melamine/calcium alginate composite structure with hydrophilic and oleophobic characteristics is designed and fabricated in the current work to realize solar interfacial evaporation based oil/water separation from emulsion. The corresponding oil/water separation process is experimentally analyzed under different material composite structures, solar intensities, and oil volume fractions. The wood-melamine/calcium alginate composite structure exhibits outstanding oil/water separation capability from emulsion under solar interfacial evaporation in comparison to the pure wood and wood-calcium alginate membrane structures owing to its fantastic oil resistance and water permeation properties. Through optimizing the thickness and aperture of hollow wood cylinder, a maximum interfacial water evaporation rate of 5.74 kg•m−2•h−1 is achieved under 5 sun solar intensity for oil/water separation. Besides, an outdoor experiment under natural sunlight (622 W•m−2 to 769 W•m−2) in summer time is also carried out for oil/water separation from emulsion using designed wood-melamine/calcium alginate composite under interfacial evaporation, and an average water evaporation rate of 0.965 kg•m−2•h−1 is obtained with condensed water on the hydrophobic glass cover for recovery. The current research paves an effective route for handling oil-in-water emulsion using renewable solar energy, contributing to the water resource protection and environmental sustainable development. [ABSTRACT FROM AUTHOR]

Many studies have shown that dropwise condensation can enhance air-side heat transfer coefficients by at least an order of magnitude relative to filmwise condensation. However, among the hundreds of superhydrophobic surface-modification processes previously reported, there remains a lack of coating methods that enable stable dropwise condensation and can be applied to aluminum—by far the most common material for the air side of heat exchangers, e.g. in air conditioning. Here we present a bottom-up synthesis technique to grow zinc oxide-based films on to aluminum with tunable nanoporosity and strongly re-entrant surface features. These surfaces exhibit exceptional static water contact angles of up to 178° with a hysteresis less than 3° and a slide angle of 1°. We have further characterized the surfaces in the presence of six different liquids, and show that our optimal surface can repel even dipropylene glycol with a contact angle of 124°, even though its surface tension is less than half that of water. Crucially, we have also tested our films under water-condensing conditions in flowing air, characterizing the droplet-shedding behavior, and we have understood how to tune the growth process to deliver stable droplet-shedding instead of flooding. The process uses inexpensive reagents, can operate below 100 °C via immersion in an aqueous bath, and takes 1–3 h to complete, making it readily scalable to areas of many square meters and complex geometries.

Objective Improve the production management level of beneficial wells in CO2 flooding pilot test area of an oilfield in Yan' an area, better and systematically evaluate the implementation effect of CO2 flooding pilot test. Methods A set of intelligent oil well metering device is developed by adopting a vertical double-volume metering structure, designed a pressure balance tube, applying GN704 new oleophobic and hydrophobic material, and integrating CO2 gas and water analyzer, gas flowmeter and other equipment. Results The field test results show that the measurement error of liquid production is less than 4%, the measurement error of water content is less than 4%, and the measurement error of associated gas is less than 7%. Conclusions The device has a compact structure and a good gas-liquid separation effect, which can realize the three-phase measurement of oil, gas and water in a single well and the analysis of CO2 content in associated gas, and also can effectively solve the problem of the impact of crude oil hanging on the measurement accuracy in winter. It is of great significance to the application effect evaluation and field popularization of CO2-EOR technology. [ABSTRACT FROM AUTHOR]

The competition among sheet-metal-forming manufacturers in recent years has become more severe. Many manufacturers have survived by cutting their production costs. Increasing the formability, which could reduce the production costs, is the focus of many manufacturers and engineers. In the present research, to increase the formability over the limiting drawing ratio (LDR) in the cylindrical deep-drawing process, the application of oleophobic coating is proposed. An SUS304 (JIS standard)-stainless-steel cylindrical deep-drawn component was used as the investigated model. First, we applied the oleophobic coating in the sheet-metal-forming process, and tribology tests were carried out to examine the friction coefficients, which were reduced by approximately 60% compared with those of standard lubricant use (Iloform TDN81). Next, deep-drawing tests were performed to investigate the drawing ratio (DR). The LDR recommended in the past could be overcome, and it increased by approximately 12% with the oleophobic coating use. Finally, the deep-drawing mechanism using an extremely low friction coefficient was clarified as well. Based on these results, an oleophobic coating could be applied in the cylindrical deep-drawing process to increase the LDR. The results also clearly expose the multidisciplinary approach that combines an oleophobic coating application and the sheet-metal-forming process.

The non-linear energy deposition associated with ultrafast laser processing enables us to create sub-wavelength nanostructures on a variety of materials; therefore, ultrafast laser processing is proved to be a versatile tool for the generation of surface functionalities such as superhydrophobic and self-cleaning surfaces. Float glass is an important material used in automobile for the windshields and mirrors. Windshields with functional properties like self-cleaning without compromising the transparency and bulk material properties is a tough challenge. In this direction, a successful attempt has been made by creating laser-induced surface structures on the float glass surface without reducing the transparency by picosecond laser processing. The initiation and growth of laser-induced surface structures have been studied with respect to number of pulses applied to the spot and the variation of density of the nanostructures by a spatial shift of laser beam. The wetting property evaluation was found to be superhydrophobic and oleophobic. [ABSTRACT FROM AUTHOR]

In this study, a brand-new, easy, and environmentally friendly approach for chemically functionalizing 2,2,6,6-tetramethylpiperidinyloxyl radical (TEMPO)-oxidized cellulose nanofiber (TOCNF) to produce modified cellulose nanofiber (octadecylamine-citric acid-CNF) was proposed. Effects of octadecylamine (ODA)/TOCNF mass ratio on the chemical structure, morphology, surface hydrophobicity and oleophobicity were studied. According to Fourier transform infrared spectroscopy (FTIR) analysis, ODA was successfully grafted onto the TOCNF by simple citric acid (CA) esterification and amidation reactions. Scanning electron microscopy (SEM) showed that a new rough structure was formed on the ODA-CA-CNF surface. The water contact angle (WCA) and the castor oil contact angle (OCA) of the ODA-CA-CNF reached 139.6° and 130.6°, respectively. The high-grafting-amount ODA-CA-CNF was sprayed onto paper, and the OCA reached 118.4°, which indicated good oil-resistance performance. The low-grafting-amount ODA-CNF was applied in a pH-responsive indicator film, exhibiting a colour change in response to the pH level, which can be applied in smart food packaging. The ODA-CA-CNF with excellent water/oil-resistance properties and fluorine-free properties can replace petrochemical materials and can be used in the fields of fluorine-free oil-proof paper. [ABSTRACT FROM AUTHOR]

Here, a facile bottom‐up nanofabrication technology for making smart superhydrophobic coatings with switchable wettability and tunable optical properties by integrating shape memory polymers (SMPs) with templated macroporous photonic crystals is reported. Thermoresponsive shape memory efforts exhibited by a polyurethane‐based shape memory copolymer enable reversible microstructural transitions between a "memorized" permanent configuration composing of highly ordered arrays of macropores and a temporary deformed structure with collapsed macropores. The unique macroporous SMP photonic crystal arrays with large surface roughness can entrap a large portion of air in the interconnecting macropores, resulting in superior superhydrophobic properties including high apparent water contact angle (CA > 160°) and low CA hysteresis. Importantly, the shape memory‐enabled microstructural transitions lead to drastic wettability switching from superhydrophobic (CA > 160°) to hydrophobic (CA ≈ 110°) or from oleophobic (CA ≈139° for hexadecane) to oleophilic (CA ≈ 80°). The large CA tunability (>50°) coupled with the simultaneous color change from shining iridescence to colorless associated with the same microstructural transition can not only provide a noninvasive means for visually indicating the surface wetting states, this favorable coupling between the wetting and optical behaviors of macroporous SMP photonic crystal membranes can also pave the way for developing new tunable nanooptical devices. [ABSTRACT FROM AUTHOR]

This paper we present several innovative aspects regarding the UHF (ultra high frequency) microwaves used in textile functionalization for obtain a dielectric surface. The UHF microwaves (MW) are in the range 300 MHz÷3 GHz. In general, the microwaves are in the range between 300 MHz and 300 GHz, but for our experiment was used the microwaves at the 2.45 GHz frequency. The microwaves are generated by a magnetron device and used for textile functionalization in order to accelerate the polymerization reaction.This work is a survey regarding the microwave applications for textile functionalization for setting the textile functionalization process by microwaves. The innovative technologies, such as plasma or microwave, have been used frequently in physics area research and in electronics. Both plasma and microwave devices operating in the field of radio waves, LF, UHF [1] and in general, the radio waves are used for TV signals transmission, for satellite communications and mobile telephony. The microwave radiation is is produced by magnetron microwave generator in microwave cavity (vacuum tube). However, for our experiment was used the microwaves at 2.45 GHz. Microwaves (MM) system are based on the absorption of a relatively strong radiation of this frequency in materials (plastics, textiles). The microwaves propagation on the textile materials depends on the dieletric material property.

Light on optoelectronic devices and solar panels is lost both through reflection at the air/glass interface of the cover glass and through scattering or absorption by accumulated dust, dirt and ice. Therefore, the transparent superhydrophobic thin films can resolve these problems. In this research, silica-silica nanotube nanocomposite thin films were applied on glass substrates by a sol–gel method. To modify the nanocomposite thin film, the samples were immersed in a PFTS solution. The morphology, chemical composition and transparency of the thin films were investigated using FE-SEM, FTIR and UV–VIS–NIR spectrophotometer methods. The water and oil contact angles on the thin film surfaces was measured using a contact angle analyzer. The self-cleaning and stability of the thin films were investigated. The water contact angle results indicated that silica nanotube/PFTS thin films increased water contact angle of the glass substrate from 16° to 152°. The transmittance of the silica-silica nanotube/PFTS coated glass substrate was measured as 87% at 550 nm. The icing test results showed that superhydrophobic coating increased icing time during ice formation on the glass surface from 102 to 874 s. [ABSTRACT FROM AUTHOR]

Certain biobased polymers or natural compounds can be effectively used in superhydrophobic coating formulations to reduce environmental impact of fluorinated compounds and related bioaccumulation and toxicity problems. Many environmental concerns have thus far been raised in relation to toxicity of solvents and C8 fluorine chemicals. Elimination of these important elements from non-wettable coating formulations can jeopardize non-wetting performance significantly. However, intelligent and innovative approaches that introduce ecofriendly resins and compounds in superhydrophobic coating formulations without significantly altering self-cleaning superhydrophobicity are possible and being reported. Superhydrophobic coatings based on a biomass-derived bioresin polyfurfuryl alcohol (PFA) were prepared. The coatings were made by blending PFA resin with a C6 perfluorinated acrylic copolymer PFAC in solution and subsequent spray coating. Silica nanoparticles were also added in order to repel some common oils. Coating morphology, chemical and thermal properties, biocompatibility and bacterial adhesion properties were studied in detail. Coatings having 50 wt% bioresin revealed equal water-repellency performance comapred to 100% PFAC-based coatings. Healthy cell growth was maintained on the coatings with no cell toxicity using human cell line, HeLa cells. Superhydrophobic coatings demonstrated very low bacterial adhesion to E. coli , S. aureus and Ps. aeruginosa indicating promising biofouling resistance. The coatings did not require any post thermal annealing. This would cause significant energy savings for large-scale adaptation. [ABSTRACT FROM AUTHOR]

In this work, a facile approach through UV polymerization is developed for the preparation of highly oleophobic and superhydrophilic coating on polyester fabric by using short‐fluorochain acrylate (1H,1H,2H,2H‐tridecafluoro‐n‐octyl acrylate) together with hydrophilic monomer and crosslinker. The coated fabric has an oil contact angle of ≈146° for hexadecane and >150° for many other oils including cooking oil and engine oil. A water drop can completely spread on the fabric within 68 ms. As a result, oil drops on the fabric surface can be easily lifted off by immersion in water. Because of its selective wettability to water, the coated fabric can also be used for oil–water filtration or water absorption from bulk oil. It is further demonstrated that the coated fabric has good hygroscopic and antistatic properties. Fabrics with these functions may find applications including oil–water separation and especially functional clothing for which the oil repellency and easy oil removal are essential while the water repellency is less important. Antistatic properties as shown by this material, are also demanded, in areas such as work clothing for auto repair and oil industries. [ABSTRACT FROM AUTHOR]

The construction of efficient solar steam generation systems is of great importance for a range of purposes, such as desalination, distillation, and sterilization. In this study, superhydrophilic and oleophobic porous architectures are prepared by carbonization of a mixture of basalt fibers and tissue paper (BFT) followed by an oleophobic modification (O‐BFT) to form oil‐repellent photothermal materials for efficient solar steam generation. The as‐prepared O‐BFT shows high porosity, superior light absorption, and good thermal insulation (thermal conductivity=0.371 Wm−1 K−1). Correspondingly, a high solar energy conversion efficiency of 90 % is achieved with 1 sun irradiation. Its strong oleophobic wettability endows it with excellent oil‐repellent ability. Therefore, a high energy conversion efficiency of 81 % in oily water was obtained with 1 sun irradiation, whereas the unmodified BFT only shows a low energy conversion efficiency of 26 % because of severe oil contamination, which significantly blocks water evaporation. These unique features of O‐BFT makes enable efficient solar steam generation even in oily wastewater, showing great advantages over reported photothermal materials that display poor antifouling performance, which in turn largely extends its application range for practical solar steam generation. [ABSTRACT FROM AUTHOR]

In this study, CuS/SiO2 composite modified aerogel was prepared by the incorporation of hollow spherical CuS into methyltrimethoxysilane-based SiO2 sol and modification with hexadecafluorodecyltriethoxysilane via acid-base catalyzed sol–gel reaction and drying under ambient pressure. The CuS/SiO2 composite modified aerogel was characterized by Fourier-transform infrared (FT-IR) spectrometry, scanning electron microscope (SEM), nitrogen gas adsorption and desorption and X-ray diffraction (XRD), respectively. The effects of CuS and fluorosilane concentration on density and porosity of aerogel, oleophobic and photocatalytic properties were evaluated. The results showed that structure and physical properties of aerogel had some effect by introducing CuS and fluorosilane, and the CuS/SiO2 composite modified aerogel with density of 0.146 g/cm3 and specific surface area of 241 m2/g achieved super-oleophobicity with oil contact angle of 152.8∘ and sliding angle of 10∘, and good photocatalytic properties for methylene blue. CuS/SiO2 composite modified aerogel was prepared by the incorporation of hollow spherical CuS into methyltrimethoxysilane-based SiO2 sol and modification with hexadecafluorodecyltriethoxysilane via acid-base catalyzed sol–gel reaction and drying under ambient pressure. The results showed that the structure and physical properties of aerogel had some effect by introducing CuS and fluorosilane, and the CuS/SiO2 composite modified aerogel with density of 0.146 g/cm3 and specific surface area of 241 m2/g achieved superoleophobicity and good photocatalytic properties to methylene blue. [ABSTRACT FROM AUTHOR]

• A novel multifunctional integrated polyimide foam (PIF) was prepared. • The PIF had high temperature resistance and hydrophobic and oleophobic properties. • The PIF was hydrophobic and oleophobic at high temperature of 300 °C. In this paper, a novel multifunctional integrated polyimide foam (PIF) was prepared with high temperature resistance and hydrophobic and oleophobic properties. The glass transition temperature of the neat PIF was as high as 306 °C. After modification by fluorosilane, the contact angles of water and dimethylsilicone oil of the modified PIF were 155.1 ± 3.5° and 124.8 ± 1.8°, respectively. Meanwhile, after being treated at 300 °C, the contact angles of the modified PIF were still higher than 90° (147.3 ± 2.6° for water contact angle, 107.1 ± 2.8° for oil contact angle), exhibiting excellent hydrophobic and oleophobic properties. Excellent comprehensive performances make the prepared PIF a very promising material, which can be used in the aircraft fuel tanks. [ABSTRACT FROM AUTHOR]

The ‘formability’ of sheet metal is a major keyword referring to process design in the sheet metal forming industry. Higher formability could reflect lower production costs and time. Many studies have been carried out to improve formability in various ways, by using the finite element method and experimental approaches. In the present research, a new zoning lubricant technique is proposed. The stainless steel SUS304 square deep drawn box is used as an investigative model. Based on the material flow analysis, we found that zoning lubricant die application could reduce the difference in material flow velocity between wall and corner zones. This material flow characteristic resulted in decreased nonconcurrent plastic deformation during the deep drawing process, as well as decreased stretching in the cup wall and the delaying of the fracture. In the present research, the design of the zoning lubricant die was strictly concerned with achieving functionality related to the friction coefficient, area of zoning, and blank-holder pressure. A smaller friction coefficient positioned in the corner zone and larger friction coefficient positioned in the wall zone are recommended. It was revealed that, by appropriate zoning lubricant die application, formability could be increased in terms of box height by approximately 7 mm or 10%.

In this study, the apparent contact angles of oil droplets on the rough surfaces in water were numerically studied using the Volume of Fluid (VOF) model. The results showed that the roughness of the surface affected the wettability. By increasing the roughness of the surface, the oleophilicity of the oleophilic surface and the oleophobicity of the oleophobic surface could be increased. Furthermore, the applicability and limitations of the prediction of the underwater apparent contact angle of the oil droplet by the contact angle model were investigated by 3D numerical simulations. It suggests that Wenzel model can accurately predict the underwater apparent contact angle of oil droplets on all the oleophilic, neutral and oleophobic surfaces, and Cassie model can only be applied to the oleophobic surface and Cassie–Baxter model can only be applied to the oleophilic surface. [ABSTRACT FROM AUTHOR]

• A novel superhydrophobic and highly oleophobic coating was fabricated. • The coating had a strong adhesion to the substrate. • The synthesis process was an easy and convenient protocol which did not require intermediate or final purification steps. • The product is an emulsion, which can be adopted brushing or dipping method. Superhydrophobic and highly oleophobic coatings have the potential for self-cleaning, anti-icing, optoelectronic and antifouling application. In this study, emulsion polymerization and sol-gel methods were employed to prepare a new superhydrophobic and highly oleophobic coating. The structures, surface morphology and the properties of the coating were analyzed by IR, SEM, TG and CA. Pencil scratch test and cross-cut tape test were performed to evaluate the coating mechanical properties. The coating exhibited superhydrophobicity with a water contact angle of greater than 150° and a sliding angle of 4.42° as well as high oleophobicity as demonstrated by a diiodomethane contact angle of 147.41° and a sliding angle of 9.85°. The coating exhibited 6H pencil hardness and 5B cross-cut adhesion properties. These interesting and robust properties make them promising candidates for some applications. [ABSTRACT FROM AUTHOR]

Sol–gel (SG) pads are used to polish different types of marble tiles and obtain high-gloss, low roughness, and scratch-free surfaces. The main features of such tools are semiconsolidated abrasives and flexible substrates. Through experiments with three types of polishing methods and two different types of tools used to polish marble tiles, the polishing mechanism of SG pads was confirmed. An abrasive yield phenomenon was observed for the semiconsolidated abrasive polishing tool with a flexible matrix, which resulted in a mirrored marble surface with high gloss, and the polishing steps were simplified. For SG polishing pads, a larger abrasive can be used to obtain high-gloss marble surfaces compared to the fine abrasives used in traditional resin polishing tools. Therefore, the agglomeration problem associated with fine particle size abrasives is avoided. In addition, after SG pad polishing, the surface of the marble tiles exhibited hydrophobic properties, and the oleophobic properties were simultaneously improved. Highlights: High gloss marble surface can be obtained by sol-gel polishing pad. Properties of hydrophobic and oleophobic of marble surface were improved after sol-gel polished. Abrasive yielding is the main characteristic of sol-gel polishing pad. Abrasives with large particle sizes instead of fine particle sizes for polishing marble. [ABSTRACT FROM AUTHOR]

Among superhydrophobic materials, non-wettable textiles are probably the ones that come in contact or interact with the human body most frequently. Hence, textile treatments for water or oil repellency should be non-toxic, biocompatible, and comply with stringent health standards. Moreover, considering the volume of the worldwide textile industry, these treatments should be scalable, sustainable, and eco-friendly. Due to this awareness, more and more non-wettable textile treatments with eco-friendly processes and green or non-toxic chemicals are being adopted and reported. Although fluorinated alkylsilanes or fluorinated polymers with C8 chemistry (with ≥ 8 fluorinated carbon atoms) are the best performing materials to render textiles water or oil repellent, they pose substantial health and environmental problems and are being banned. For this reason, water/solvent-borne, C8-free vehicles for non-wettable treatment formulations are probably the only ones that can have commercialization prospects. Hence, researchers have come up with a variety of new, non-toxic, green formulations and materials to render fabrics liquid repellent that constitute the focus of this review paper. As such, this review article discusses and summarizes recent developments and techniques on various sustainable superhydrophobic treatments for textiles, with comparable performance and durability to formulations based on fluorinated C8 compounds. The current state-of-the-art technologies, potential commercialization prospects, and relevant limitations are discussed and summarized with examples. The review also attempts to indicate promising future strategies and new materials that can transform the process for non-wettable textiles into an all-sustainable technology. Unlabelled Image • Industrialization of non-wetting textile treatments now requires the use of more sustainable approaches and materials. • C8 chemistry is very effective but breaks down into toxic and bio-persistent compounds. • Alternative and potential, eco-friendly fabric treatments were reviewed. • Nanoparticles and hydrophobic polymer combinations are needed to match C8 chemistry. [ABSTRACT FROM AUTHOR]

The investigationresults presented in this article are focused on the influence of the compositionof coatings, which are used for obtaining of membranes, on their oil/water separating ability. To obtainmembranes of a special type of wettability, two compositions were chosen: fluorine-containing coating, which is based on poly(diallyldimethylammonium chloride)/pentadecafluorooctanoic acid and particles of SiO2 (PDDA/PFOA/SiO2) and coating without fluorine, which is based on hydrolyzed methyltriacetoxysilane. It is found that obtained membranes are hydrophilic, but depending onthe composition of their coating, they areoleophobic to different types of organic liquids. In particular, membranes coated with PDDA/PFOA/SiO2 possess strong oleophobicity to polar organic liquids of low density - kerosene, while membranes coated by hydrolyzed methyltriacetoxysilane are highly oleophobic to more dense organic liquids - vacuum pump and rapeseed oils. [ABSTRACT FROM AUTHOR]

Abstract Fouling is a common challenge to all membrane-based separation technologies. The current study demonstrated an antifouling membrane with a superhydrophilic but oleophobic (in air) characteristic, which was achieved through covalently tethering heterogeneously tailored two-dimensional layered double hydroxide (LDH) nanosheets to a polyvinylidene fluoride membrane surface. The nanosheets were in situ grafted with alternately arranged sodium 1-dodecanesulfonate (SDS) and 3-aminopropyltriethoxysilane (APTS) chains during preparation. Poly(methacrylic acid) (PMAA) was previously grafted on the membrane via plasma induced graft copolymerization as anchor sites for nanosheet binding. With a simple dip-coating operation, the surface-tailored LDH nanosheets could be bound to the membrane via cross-linking between the amine groups of APTS and carboxyl groups of PMAA. Ultimately, the long hydrophobic SDS and short hydrophilic APTS chains on the nanosheets formed a heterogeneous and infiltration selective (due to steric exclusion) surface on the membrane. As a result, the hydrophilic moieties on the membrane surface were much more accessible to water than to liquids of larger molecular size, thereby bringing about the superhydrophilic but oleophobic characteristic. The functionalization gave rise to both significantly enhanced wettability and hydrophilicity of the membrane, mainly owing to the increase of the electron donor component of surface energy (γ AB−). Additionally, the functionalized membrane obtained a greater permeability without compromising its selectivity. Furthermore, as verified in both filtration tests with synthetic and practical foulant solutions, the superhydrophilic and oleophobic characteristic endowed the functionalized membrane with conspicuously greater cleaning efficiency and excellent capability in resisting irreversible fouling, suggesting promising applications in various fields. Graphical abstract fx1 Highlights • A unique superhydrophilic but oleophobic (in air) PVDF membrane was fabricated. • The rationale behind the unique wetting behavior was elucidated. • The modified membrane achieved dramatically improved filtration performance. • The modified membrane obtained a remarkable antifouling behavior. [ABSTRACT FROM AUTHOR]

In this study, hierarchical micro-nano structures were constructed on cotton surface followed by low surface tension agent treatment to obtain superhydrophobic and oleophobic textile materials. The static contact angle of water, ethylene glycol, olive oil, and dodecane on treated fabric was 154 ± 3°, 145 ± 3°, 141 ± 3°, and 128 ± 1°, respectively. Hierarchical particles were prepared by chemical bonding of nanosilica onto microsilica through the reaction of epoxy group of (3-glycidyloxypropyl)trimethoxysilane and amino group of 3-aminopropyltriethoxysilane. The chemical groups were characterized by FTIR. The surface morphology and surface roughness were characterized by SEM and AFM, and the primary silica particles' size was obtained based on TEM images. The constructed micro-nano structure was demonstrated robust enough that even can maintain a good superhydrophobic and oleophobic performance after the crocking test and 50 times standard home laundering. Moreover, the tensile strength and whiteness performance of fabric still remained quite good after the treatment. This study provides a useful method to construct a robust micro-nano structure on fabric, which is meaningful for producing durable superhydrophobic and oleophobic textiles. Hierarchical micro-nano structure was constructed on fabric by sol-gel method.Superhydrophobic and oleophobic performace of fabric was durable even after washing and crocking.Tensile strength and whiteness of fabric still remained quite good after treatment. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Hypothesis Bionic superhydrophobicity including high contact angle, low sliding angle and nonstick property, combined with both strong pH and ultraviolet (UV) resistance, is difficult to simultaneously achieve for large-scale preparation of superhydrophobic surfaces by blending polymer with a nonreactive inorganic nanofiller. Experiments A series of high pH and UV-irradiation-resistant superhydrophobic nanocomposite films were prepared through UV-light-assisted chemical cross-linking among ternary components under nitrogen protection. Ethoxylated bisphenol A diacrylate, 2-(perfluorooctyl) ethyl acrylate, reactive thiol-coupled graphene nanosheets and photoinitiator were evenly mixed, followed by UV-irradiation curing. Findings Abundant 3D networks could be formed. A robust self-wrinkling surface morphology was formed due to a UV-curing-induced inner tension in the composites, 2D morphology-induced flexibility for graphene nanosheets and fluorine-bearing component-induced phase separation at the wetted surfaces. High roughness and use of the fluorine element endows the surfaces with superhydrophobicity and oleophobicity. A favorable nonstick performance was obtained. Superhydrophobicity could be maintained despite changing the film-forming substrate, pH of soaking solutions from 1 to 12, or use of a prolonged UV-irradiation time reaching 120 h. Therefore, both superhydrophobicity/oleophobicity and strong pH/UV resistance are finely balanced. This work might open up the way for large-scale fabrication of promising superhydrophobic surfaces. [ABSTRACT FROM AUTHOR]

[Display omitted] • The transparent slippery coating with dual self-healing abilities was prepared by a 3D grafting method. • The coating is highly transparent and demonstrates excellent slipperiness on water and most oils. • The coating can recover its slippery effect even after being scratched or damaged due to its intrinsic and surface self-healing abilities. Slippery surfaces are highly effective in repelling low-surface tension fluids due to their oleophobicity, anti-adhesive, and drag-reduction properties. However, it should be noted that while these surfaces show promising performance under normal conditions, they may lose their efficacy under harsh conditions, particularly in outdoor applications. In this study, we developed a transparent slippery coating with dual self-healing abilities by a 3D-grafting method. The coating can be formed on various substrates, and the coated glass is highly transparent. Additionally, the coating shows exceptional slipperiness on water and most oils, making it highly effective at repelling liquids. Moreover, the coating exhibits remarkable intrinsic and surface self-healing capabilities, enabling it to restore its slippery effect even in the presence of scratches or damage. This outstanding self-healing property results in a long-lasting, durable coating that can resist wear and tear. The exceptional slipperiness and self-healing properties of coating make them suitable for various industrial, medical, and consumer products. [ABSTRACT FROM AUTHOR]

Wood is prone to absorb water or oil due to the chemical characteristics of its components, which significantly reduces its service performance. Consequently, superhydrophobic or superoleophobic wood has great development potential in the wood industry. We coated methyltrichlorosilane (MTCS) and 1H,1H,2H,2H-perfluorodecyltrimethoxysilane (PFDMS) on Birch wood surfaces by a chemical vapor deposition method. The modified wood showed superhydrophobicity and oleophobicity, with a water contact angle (WCA) of 157.7° and an oil contact angle (OCA) of 141.3°. Due to the large number of low surface energy groups bonded onto the wood surface, it showed extremely strong repulsion to liquid water, oil and even gaseous water. Moreover, the superhydrophobic coating exhibits excellent mechanical and chemical stability and thereby allows long-term use in harsh outdoor environments. [Display omitted] • MTCS and PFDMS constructed superhydrophobic coatings on the wood surface by vapor deposition, with no waste liquid generated during the preparation process; • MTCS and PFDMS reduced the surface energy of wood and constructed micro-/nano- scale rough structures to improve the hydrophobic properties of wood; • The obtained superhydrophobic wood exhibits excellent defense not only against liquid water and oil, but also against moisture; • The superhydrophobic coating has good mechanical and chemical stability. [ABSTRACT FROM AUTHOR]

Bio-inspired surfaces with superamphiphobic properties are well known as effective candidates for antifouling technology. However, the limitation of large-area mastering, patterning and pattern collapsing upon physical contact are the bottleneck for practical utilization in marine and medical applications. In this study, a roll-to-plate nanoimprint lithography (R2P NIL) process using Morphotonics’ automated Portis NIL600 tool was used to replicate high aspect ratio (5.0) micro-structures via reusable intermediate flexible stamps that were fabricated from silicon master molds. Two types of Morphotonics’ in-house UV-curable resins were used to replicate a micro-pillar (PIL) and circular rings with eight stripe supporters (C-RESS) micro-structure onto polycarbonate (PC) and polyethylene terephthalate (PET) foil substrates. The pattern quality and surface wettability was compared to a conventional polydimethylsiloxane (PDMS) soft lithography process. It was found that the heights of the R2P NIL replicated PIL and C-RESS patterns deviated less than 6% and 5% from the pattern design, respectively. Moreover, the surface wettability of the imprinted PIL and C-RESS patterns was found to be superhydro- and oleophobic and hydro- and oleophobic, respectively, with good robustness for the C-RESS micro-structure. Therefore, the R2P NIL process is expected to be a promising method to fabricate robust C-RESS micro-structures for large-scale anti-biofouling application.

Self-cleaning windows are well known for their ability to function with airborne pollutants, but there is a growing industry for semi-permanent subaquatic optical devices, where the performance of such windows should be considered. Here sol-gel technology is explored as a means of producing self-cleaning, subaquatic, sapphire windows. We demonstrate removal of marine bacteria and, in the worst-case contamination scenario, dead North Sea crude oil (API 35). This greasy contaminant was smeared across the windows to effectively reduce optical transmission strength to just 54%. The titania-based sol-gel-coated windows can restore transmission to within 10% of the clean value in less than one day, unlike standard sapphire windows, which lose 68% transmission following contamination and aquatic submergence over the same duration. A range of theories to enhance the self-cleaning performance of the sol-gel coating were explored, but none of the tested variables were able to provide any enhancement for subaquatic performance.

The paper presents a new idea of using boundary slip to facilitate hydrodynamic lubrication for zero-entrainment-velocity (ZEV) bearing contacts. The idea entails the bearing contact composed of an oleophobic (slip) and an oleophilic (nonslip) surface. While the nonslip surface drags oil into the ZEV contact, the opposite moving slip surface cannot bring the oil out. The net entrainment of oil thus facilitates hydrodynamic lubrication for the ZEV contact. The idea was validated by ZEV experiments, such that a new retainerless bearing type that incorporates alternately slip and nonslip rolling elements was conceived. The new bearing design fits for wide speed range applications. The optimal characteristics of oleophobic coating required in the new bearing are discussed. [ABSTRACT FROM AUTHOR]

In this study, a noble robust superhydrophobic and highly oleophobic polyurethane (PU)–SiO 2 nanoparticle (NP) coating is specially designed using sol-gel process. For this purpose the effective parameters on surface tension and durability of the synthesized coating investigated and optimized. This new superhydrophobic and highly oleophobic coating exhibits good pensile hardness as high as 6H with adhesive force grade of 5B and repels water and oil with contact angles (CAs) of 159° and 140°, respectively. The synthesized PU-SiO 2 composite also retains an excellent amphiphobicity after a 7 days immersion in water with water and oil with CAs of 150° and 130°. Facile fabrication of PU–SiO 2 coating with enhanced amphiphobicity and durability provides a novel pathway to the development of a high performance superamphiphobic surfaces. The outstanding properties of synthesized PU–SiO 2 coating are mainly due to (i) reduction of surface energy by fluoroalkylsilanes, (ii) formation of hierarchical micro- and nanometer scale roughness structures on the coating surface, (iii) stable adhesion of SiO 2 NPs into PU resin after cross-linking with isocyanate, and (iv) improving the chemical bonding and electrostatic interactions between film and substrate. [ABSTRACT FROM AUTHOR]

ABSTRACT: The fabrication of novel hydrophobic, superhydrophobic, and oleophobic surfaces on glass using nanosilica particles modified with polymer brushes prepared via surface initiated Cu(0)‐mediated reversible‐deactivation radical polymerization was demonstrated. Monomers including n‐butyl acrylate, 2,2,2‐trifluoroethyl methacrylate, and 1,1,1,3,3,3‐hexafluoroisopropyl acrylate were used to synthesize a series of nanosilica–polymer organic/inorganic hybrid materials. Products were analyzed using infrared spectroscopy, thermogravimetric analysis, scanning and transmission electron microscopy. The coated nanosilica showed core–shell structures that contains polymer brushes up to 67 wt %. The application of these particles for modifying surface wettability was examined by covalently attaching them to glass via a recently developed one‐pot “grafting to” methodology using “thio‐bromo click” chemistry. Atomic force microscopy topographic images show up to 25 times increase in roughness of the coated glass compared to blank glass sample. Contact angle measurements showed that nanosilica coated with PBA and PTFEM produced hydrophobic glass surfaces, while a superhydrophobic and oleophobic surface was generated using nanosilica functionalized with PHFIPA. This novel methodology can produce superhydrophobic and oleophobic surfaces in an easy and fast way without the need for tedious and time‐consuming processes, such as layer‐by‐layer deposition, high temperature calcination, and fluorinated oil infusion. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 [ABSTRACT FROM AUTHOR]