A facile and low-cost preparation of durable amphiphobic coatings with fluoride–silica@poly(methacrylic acid) hybrid nanocomposites

Poor robustness, high cost and complicated preparation are the main barriers to the large-scale industrial application of amphiphobic coatings. A facile and low-cost method to fabricate durable amphiphobic coatings is reported in this work. The coatings were composed of top and bottom paints. The top paint was prepared by the F–Si@PMAA hybrid nanocomposites dispersion. The hybrid nanocomposites with dual structure were prepared via the co-condensation reaction of tetraethoxysilane (TEOS) and 1H,1H,2H,2H-Perfluorodecyl triethoxysilane (HDFTES) on the surface of the presynthesized PMAA nanoparticles in ethanol dispersion. The bottom one was a type of inexpensive car refinishing paint. The resulting coatings could be sprayed onto different substrates. All the coated substrates exhibited good amphiphobicity with superhydrophobicity with the water contact angle greater than 150°, water roll-off angle less than 4°, and high oleophobicity with the oil contact angle greater than 130°. Moreover, all of the prepared coatings exhibited great robustness after water jetting, sand abrasion, and knife scratching. This method can be an effective strategy for fabricating amphiphobic surfaces for practical industrial applications.     

Adhesion aspects of poly(p-xylylene) to SiO2 surfaces using γ-methacryloxypropyltrimethoxysilane as an adhesion promoter

The use of organo-silanes as coupling agents offers the potential to create novel structures using materials that would otherwise suffer from poor adhesion. γ-methacryloxypropyltrimethoxysilane (γ-MAPTS) layers were deposited on hydroxylated SiO₂ surfaces using both vapor and solution deposition techniques. The films were characterized using variable angle spectroscopic ellipsometry, infrared spectroscopy, contact-angle measurements and X-ray photoelectron spectroscopy. Film thickness was relatively constant at ～6 Å for solution deposition times from 2 min to 2 h at 60° C. Water contact angle increased from 0° to 45° after silane deposition from solution. Room temperature vapor-deposited γ-MAPTS films showed similar thicknesses to those of solution deposited films but a markedly lower contact angle of 10°. Parylene N was chemical vapor deposited on the γ-MAPTS films and its adhesion was tested using the Scotch^® Tape test. The γ-MAPTS improved adhesion of parylene N to the hydroxylated surface, with the adhesion for the vapor deposited silane films exhibiting a temperature and time dependence.     

Gas barrier and wetting properties of whey protein isolate‐based emulsion films

The aim of this research was to investigate the effect of rapeseed oil concentration (1–3% w/w) on the water vapor, oxygen and carbon dioxide permeability, water vapor sorption and surface properties of whey protein isolate emulsion‐based films. The water contact angle as affected by oil content, film side and time was analyzed. The effect of temperature (5 and 25°C) on the water vapor permeability (WVP), water vapor sorption kinetics and diffusion coefficient was also studied. The results showed that the incorporation of a lipid phase to whey protein film‐forming solutions was able to decrease the WVP, water hydrophilicity (increasing water contact angle) and water transfer of whey protein films. However, the films containing oil were more permeable to oxygen and carbon dioxide. Significantly higher values of WVP and diffusion coefficient were obtained at 5°C than at 25°C, indicating that storage temperature should be taken into account when designing the composition of edible films and coatings for food applications. POLYM. ENG. SCI., 59:E375–E383, 2019. © 2018 Society of Plastics Engineers     

One‐step fabrication of fluoropolymer transparent films with superhydrophobicity by dry method

Fluoropolymer transparent thin films were deposited on different substrates by one‐step vacuum evaporation method, which exhibit superhydrophobic property with water contact angle (CA) greater than 150°. Polytetrafluoroethylene (PTFE) film with network structure shows high oleophobicity with oil CA of 138°, whereas polytetrafluoroethylene‐perfluoropropylvinylethers (PFA) film with particle structure is superoleophilicity with oil CA near 0°. It is believed that different conformation of  CF₂ groups at the surface lead to this different surface activity. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Transparent polysilicone coatings as protecting films for gold commemorative coins

Novel transparent organic silicone resin coatings were successfully prepared through the reaction between the alkoxy groups of methyltrimethoxy‐silane (MTMS) and γ‐aminopropyltriethoxysilane (APTES) and hydroxyl groups of hydroxyl terminated silicone oil (HTSO). The influences of different monomer feed mass ratio on the coating properties were investigated via measuring the hydrophobicity and hardness of coating films. The coating films were characterized with IR, UV, TG, scanning electron microscope (SEM), and automatic contact angle meter. Some properties of coating films, such as adhesion, impact resistance, and wear‐resistance, were also evaluated. The results indicated that these coating films formed on the surfaces of gold commemorative coins possessed some good properties including high hydrophobicity, high water contact angles, high light transmittance, good heat‐resistance, adhesion, hardness, and weatherability, etc. Moreover, the uniform, clear, transparent, and dense coating films did not cover the symphony surface patterns or affect the metallic luster. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Characterization of superhydrophobic a-C:F thin film deposited on porous silicon via laser ablation of a PTFE target

Fluorinated amorphous carbon (a-C:F) thin films are deposited on both flat silicon and porous silicon (PS) surfaces via laser ablation of a polished polytetrafluoroethylene (PTFE). Porous silicon (PS) is prepared by anodic etching of p-type silicon wafers in HF based solution. The film deposited on the flat silicon surface exhibits a highly hydrophobic state with water contact angle (WCA) of ~ 146°. In comparison, the surface of film deposited on PS layer shows a roll-off superhydrophobic state, where the water droplet is seen to roll off without wetting its surface with contact angle hysteresis of ~ 4.5°. Micro-Raman results show that the graphite domain of the film deposited on PS has higher disorder level and lower average gain size. The effect of substrate porosity on chemical composition of deposited films has been investigated by using both Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS). It is found that the porous substrate improves the incorporation of the fluorine into the film. Atomic force microscopy (AFM) results revealed that the film deposited on PS has higher surface roughness and lower grain size as compared to the film deposited on flat silicon surface.     

Above 170° water contact angle and oleophobicity of fluorinated graphene oxide based transparent polymeric films

Understanding and tuning the wettability of the surfaces are highly intriguing for various applications. The development of stable and transparent coatings over aluminium alloys and glass substrates for making them superhydrophobic and extended oleophobic (lower to the surface tension of 33.4 mN/m (coconut oil)) using a scalable and simple spray painting technique is demonstrated. Fluorinated graphene oxide (FGO, fluorine content of 34.4 atomic weight %), an atomically layered material, modified Polydimethylsiloxane (PDMS) polymer composite is used as the paint for the coatings. The coated films were studied for their surface and compositional features. A water contact angle (CA) of 173.7° (close to the highest ever reported water CA, 175°) is achieved with 60 wt% FGO in PDMS, and the same showing a CA of 94.9° with coconut oil, in conjunction with a low contact angle hysteresis (4°). The work of adhesion with the amount of FGO is studied and the surface energy of FGO containing paints is calculated and compared with the bare paints using Zisman plot analysis.     

Photopolymerized low‐surface‐energy coatings based on a novel fluorinated ether acrylate

The synthesis, characterization, and polymerization of a perfluoroalkyl ether substituted methacrylic acid (C8F7) were investigated. C8F7 was photopolymerized at different temperatures, higher double‐bond conversions being achieved at higher polymerization temperatures. The polymerization rates were fast in comparison with those of typical methacrylate esters. Thermogravimetric analysis of the obtained polymers showed thermal stabilities up to 270–290°C. The initial degradation at 200°C involved the loss of water and the partial loss of the perfluoroalcohol via the intramolecular formation of anhydride and lactone groups. The surface properties of coatings obtained with C8F7 coatings on various substrates were evaluated with water and hexadecane contact‐angle measurements, which confirmed that low‐surface‐energy polymeric coatings were obtained. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 3301–3314, 2004     

Preparation,surface wetting properties,and protein adsorption resistance of well‐defined amphiphilic fluorinated diblock copolymers

Novel well‐defined amphiphilic fluorinated diblock copolymers P(PEGMA‐co‐MMA)‐b‐PC₆SMA were synthesized successfully by RAFT polymerization and characterized by FTIR, ¹HNMR and GPC. For copolymer coatings, static contact angles, θ, with water (θ_water ≥ 109.5^°) and n‐hexadecane (θ_hexadecane ≥ 68.9^°) pointed to the simultaneous hydrophobic and lipophobic characteristics of the copolymer surfaces. Dynamic contact angle measurements indirectly demonstrated that copolymer films underwent surface reconstruction upon contact with water, which results in a surface with surface coverage of polar PEG units. Moreover, the distinct nanoscale microphase segregation structures were proved by atomic force microscopy (AFM) images. Finally, using bovine serum albumin (BSA–FITC) as the model protein, copolymers exhibited excellent protein adsorption resistance. It is believed that the combination of surface reorganization and nanometer‐scale microphase segregation structure endows the excellent protein resistance for amphiphilic fluorinated copolymers. These results provide deeper insight of the effect of surface reconstruction and microphase segregation on the protein adsorption behaviors, and these amphiphilic fluoropolymers can expect to have potential applications as antifouling coatings in the field of marine and biomedical. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41167.     

Oleophilic modification of poly(vinyl alcohol) films by functionalized soybean oil triglycerides

In this study, maleinized (SOMAP) and isocyanated soybean oil (SONCO) triglycerides have been successfully grafted onto one surface of poly(vinyl alcohol)(PVA) films to give films that are hydrophilic on one side and hydrophobic on the other. The surface grafting was accomplished by the reaction of succinic anhydride or isocyanate functionalities of soybean oil derivatives and the hydroxyl groups of PVA films. The reaction was run in toluene, using PVA films on glass slides so that only one side of the film was accessible. After grafting, the films were rinsed with hot toluene to remove ungrafted triglycerides from the surface. The reaction on the surface was confirmed by ATR‐FTIR and ¹H‐NMR spectroscopic techniques. A series of films were prepared at different concentrations of SOMAP or SONCO in toluene. The increase in hydrophobicity with an increase in SOMAP or SONCO concentrations was observed by water contact angle measurements. The contact angles on the grafted side of the film reach their maximum value of 88° and 94° for 26 and 2.5% SOMAP and SONCO concentrations in toluene, respectively, while the ungrafted side gives contact angle of 48°. Surface morphologies of PVA‐g‐SOMAP and PVA‐g‐SONCO films were investigated by atomic force microscopy, whereas optical microscopy and staining was used to determine the homogeneity of the films. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Preparation and fluorine enrichment behavior of fluorinated polyester

Poly[1,2-propylene glycol-3-(2,2,3,3,4,4,5,5,6,6,7,7-dodecafluoroheptoxy)]phthalate (PDFP) was prepared by the reaction of phthalic anhydride, epichlorohydrin, and 2,2,3,3,4,4,5,5,6,6,7,7-dodecafluoroheptyl glycidyl ether (DFGE). The structure of PDFP was characterized with ¹H-NMR, ¹⁹F-NMR, FTIR and the wettability of water and oil on cured PDFP coatings was investigated by contact angle meter. The results showed that the contact angle of water and diiodomethane on cured coatings increased with the increase of the fluorine content and could maximally attain 108° and 69°, respectively. At a fluorine content of 0.75%, the surface energy was 21.1 mJ/m². X-ray photoelectron spectroscopic (XPS) analysis showed that the surface F/C atomic ratio was much higher than the overall F/C molar ratio, indicating that the fluoroalkyl groups in PDFP had enriched on the coating surface. It was also found that the fluorinated polyester with longer fluoroalkyl groups had the higher tendency to enrich on the coating surface.     

Synthesis of fluoroalkyl‐modified polyester and its application in improving the hydrophobicity and oleophobicity of cured polyester coatings

The fluoroalkyl‐modified polyester (PE‐F_n) was synthesized by the reaction of polyester resin (PE) and fluorinated isocyanate, and the structure of the synthesized product was characterized by proton nuclear magnetic resonance (¹H‐NMR) and fluorine nuclear magnetic resonance (¹⁹F‐NMR). The water and oil wettability of the cured PE coatings with PE‐F_n as additives was investigated by contact angle meter. The results showed that the introduction of an extremely low concentration of PE‐F_n into PE led to the increase in contact angle of water and diiodomethane on cured PE coatings, and the decrease in the surface free energy. The X‐ray photoelectron spectroscopic (XPS) analysis showed that the F/C molar ratio in the outer few nanometers was significantly higher than that in the bulk, indicating that the fluoroalkyl groups in PE‐F_n had enriched on the coating surface. It was also found that longer fluoroalkyl groups and fluoroalkyl groups with ? CF₃ at its end had the higher tendency to aggregate on the coating surface. The topological structures of the cured coatings were recorded by an atomic force microscope under tapping mode and the results revealed that there was a strong surface segregation of fluorinated species. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39812.     

Fabrication of two sites hydrophobicity on cotton surface – a fluoropolymerization approach

Cotton fabric on both surfaces was coated with polymerization of fluoromonomer followed by adsorption of fluorosurfactant by a new technique admicellar polymerization to obtain durable hydrophobicity. Water repellence properties were determined in terms of simple drop test contact angles. The coating on cotton fabric exhibited the right water contact angle of 137.23° and left contact angle 138.35° (an average value of 137.79°). However, the durability of the coatings was decreased after simple home laundering with a decrease in water contact angle value. The surface morphology was evaluated by scanning electron microscopy before and after polymerization. Beside this chemical composition on the cotton, the surface was evaluated by EDS analysis to determine the number of fluorine moieties deposited on the cotton surface by this technique.     

Corrosion-resistance,robust and wear-durable highly amphiphobic polymer based composite coating via a simple spraying approach

This study successfully developed a simple spray approach to fabricate a robust highly amphiphobic poly(phenylene sulfide) (PPS)/fluorinated ethylene propylene (FEP)/poly(dimethylsiloxane) (PDMS) composite coating with high-performance in corrosion-resistance, wear-durable through designing the nano/micro two-tier roughness and fluorinating with materials of the low surface free energy. The highly amphiphobic and tribological properties of the coatings were measured by the contact angle meter and the pin-on-disc tribometer, respectively. It was interested to observe that the composite coating showed superhydrophobic and highly oleophobic simultaneously, with the highest contact angles of water, glycerine and ethylene glycol up to 173 ± 2.1°, 142 ± 2.2° and 139 ± 2.1°, respectively. Moreover, the surfaces of the PPS/FEP composite coatings were investigated by means of Fourier transform infrared spectroscopy (FT-IR), X-ray diffractometry (XRD) and energy-dispersive X-ray spectroscopic (EDS). The robust highly amphiphobic coating also showed remarkable durability against strong acid and strong alkali in the pH range from 1 to 14. After 47 h sliding wear test, no failure sign on the PPS/45%FEP/PDMS composite coating was observed. Such unique characteristics were attributed to the synergistic effect of the nano/micro two-tier roughness and fluorinating with low surface free energy groups (–CF₂–, –CF₃–).     

Fabrication of durable hydrophobic cellulose surface from silane‐functionalized silica hydrosol via electrochemically assisted deposition

Durable excellent hydrophobic surface on cellulose substrate was fabricated from the silica hydrosol functionalized with silane chemicals by a facile electrochemically assisted deposition technique. The silica hydrosol was synthesized using tetraethoxysilane (TEOS) as the precursor and sodium dodecylbenzene (SDBS) as the emulsifier under acidic conditions. The hydrophobic silane modifiers including octyltriethoxysiliane (OTES), dodecyltriethoxysiliane (DTES) and isooctyltriethoxysiliane (iso‐OTES) and the silane‐coupling agent γ‐mercaptopropyltriethoxysilane (MPTES) were used to dope the silica hydrosol for preparing durable hydrophobic cellulose surface. The cellulose surface modified with silane modifier iso‐OTES exhibited the best hydrophobicity with water contact angle of 162.3 ± 0.5° due to its non‐polar and hydrolytically stable of ? Si(C₈H₁₇) groups. The addition of silane‐coupling agent MPTES containing the ? SH group led to good durability of hydrophobicity with water contact angle of 130.0 ± 1.2° after 20 washing times. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42733.     

Effect of oxygen plasma treatment on non-thrombogenicity of diamond-like carbon films

The non-thrombogenicity of oxygen-plasma-treated DLC films was investigated as surface coatings for medical devices. DLC films were deposited on polycarbonate substrates by a radio frequency plasma enhanced chemical vapor deposition method using acetylene gas. The deposited DLC films were then treated with plasma of oxygen gas at powers of 15 W, 50 W, and 200 W. Wettability was evaluated by water contact angle measurements and the changes in surface chemistry and roughness were examined by X-ray photoelectron spectroscopy and atomic force microscope analysis, respectively. Each oxygen-plasma-treated DLC film exhibited a hydrophilic nature with water contact angles of 11.1°, 17.7° and 36.8°. The non-thrombogenicity of the samples was evaluated through the incubation with platelet-rich plasma isolated from human whole blood. Non-thrombogenic properties dramatically improved for both 15 W- and 50 W-oxygen-plasma-treated DLC films. These results demonstrate that the oxygen plasma treatment at lower powers promotes the non-thrombogenicity of DLC films with highly hydrophilic surfaces.     

From lotus effect to petal effect: Tuning the water adhesion of non-wetting rare earth oxide coatings

A facile post-deposition plasma treatment was developed to tune the wetting behavior of Yb₂O₃ coatings deposited via the solution precursor plasma spray process. The as-deposited coatings exhibited the lotus effect after vacuum treatment, with a water contact angle of ∼162° and a roll-off angle of ∼5°, due to the hierarchical columnar microstructure. When the plasma torch was scanned over the coatings as a post-deposition treatment, the rough top surfaces of the columns present in the as-deposited coatings became smooth, and the coatings then exhibited the petal effect, with a water contact angle of ∼150° to ∼130° and high, tunable adhesion to water. Analysis of the surface compositions showed that after vacuum treatment hydrocarbon adsorption on the as-deposited coatings and plasma-treated coatings was very similar. A mathematical model correlating surface structures with wetting behaviors was developed to elucidate the transition from the lotus effect to the petal effect.     

Efficient one-step fabrication of superhydrophobic nano-TiO2/TMPSi ceramic composite coating with enhanced corrosion resistance on 316L

TiO₂ Nanoparticle/Trimethoxy(propyl)silane (TMPSi) ceramic composite coating was deposited on 316L steel using a one-step electrophoretic deposition (EPD) method. Silane coupling agent (TMPSi) was added to the EPD bath in different concentrations (from 0.5 to 15 vol %) to decrease the surface energy of the deposited coating. TiO₂ coating is hydrophilic whereas by adding varying concentrations of TMPSi, the obtained nanocomposite coating showed much better hydrophobicity. Surface wettability was measured by water contact angle (WCA) and sliding angle (SA) tests. Moreover, the effect of TMPSi concentration was determined by comparing the WCA and SA values. Surface morphology was studied through Field Emission Scanning Electron Microscopy (FESEM), and the presence of micro/nano meter roughness on the surface was confirmed. The distribution of elements were investigated by EDS analysis in which their uniform dispersion was observed. Corrosion behavior of 316L samples before and after the coating process was studied by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) tests in 3.5 wt % NaCl solution. The polarization curve proved that the superhydrophobic ceramic nanocomposite coatings (WCA = 168° and SA = 3.1°) were able to decrease the corrosion rate of bare 316L (from 12.180 to 5.621 (μm per year)).     

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。     

Hydrophobic properties of films grown by torch-type atmospheric pressure plasma in Ar ambient containing C6 hydrocarbon precursor

The direct deposition of polymeric films with a torch-type atmospheric pressure plasma using benzene, n-hexane and cyclohexane in Ar was performed on several substrates. The surface morphologies of the films deposited with n-hexane and cyclohexane were uniformly smooth for all deposition thicknesses, and the typical water contact angle on the films indicating the degree of hydrophobicity was about 85o. However, the films deposited using benzene had a micro-coarse surface morphology and showed a superhydrophobic property with a water contact angle exceeding 150°. Some trace of oxygen incorporation was shown in all films due to the plasma deposition process in an air ambient. The small amount of oxygenated species did not lead to a decrease of hydrophobicity of the films.