Femtosecond laser micro/nano fabrication for bioinspired superhydrophobic or underwater superoleophobic surfaces

The preparation of superhydrophobic or underwater superoleophobic interface materials has become a research hotspot because of their wide application in self-cleaning, drag reduction, oil-water separation, anti-oil pollution and so on. The unique wettability of organisms gives inspiration to design and create new interface materials. This review focuses on the recent research progress of femtosecond laser micro/nano fabrication for bioinspired superhydrophobic or underwater superoleophobic surfaces. This review starts with a presentation of the related background including the advantages of femtosecond laser and wettability theoretical basis. Then, organisms with unique wettability in nature, the preparation of superhydrophobic or underwater superoleophobic surfaces by femtosecond lasers on different materials, and their related important applications are introduced. Finally, the current challenges and future prospects with regard to this field are provided.

Synthesis and Characterization of Superhydrophobic-Superoleophobic and Anti-Corrosion Coatings via Sol-Gel Process

Superoleophobic nanocomposite coatings with improved hydrophobic properties were obtained by incorporation of a perfluoroalkyl polymer in hybrid sol-gel matrix containing silica and titania nanoparticles. SiO2 and TiO2 nanoparticles were synthesized based on sol-gel precursors utilizing tetraethyl orthosilicate, 3-glycidoxypropyl trimethoxysilane, and tetra (n-butyl orthotitanate). SEM and EDX images of the coating demonstrated that a Silica nanosphere had been aggregated in superporous structure. The analysis results show that nano-sized inorganic particles (10 - 20 nm) have a uniform distribution and dispersion. By increasing the PFOTES, the oleophobicity of coatings increased due to lowering of surface energy in the presence of fluoropolymer. Results of EIS measurement show that PFOTES and TiO2 nanoparticles increased anti-corrosion property of hybrid coatings. This method introduces a simple way to produce water- and oil-repellent self-cleaning coatings on large areas of different substrates like glass, ceramic, metal and composites.

Green Fabrication of Underwater Superoleophobic Biopolymeric Nanofibrous Membranes for Effective Oil-Water Separation

Currently,most of the materials for oil-water separation membranes are limited to fluorine-based polymers with low surface energy.However,it is not biodegradable and requires large amounts of organic and toxic solvents in the membrane manufacturing process.Therefore,interest in the development of a new eco-friendly oil-water separation membrane that does not cause secondary pollution and exhibits selective wettability characteristics in water or oil is increasing.The biopolymeric nanofibrous membranes inspired by fish skin can provide specific underwater oleophobicity,which is effective for excellent oil-water separation efficiency and prevention of secondary contamination.Fish gelatin,which is highly soluble in water and has a low gelation temperature,can be electrospun in an aqueous solution and has the same polar functional groups as the hydrophilic mucilage of fish skin.In addition,the micro/nanostructure of fish skin,which induces superoleophobicity in water,introduces a bead-on-string structure using the Rayleigh instability of electrospinning.The solubility of fish gelatin in water was removed using an eco-friendly crosslinking method using reducing sugars.Fish skin-mimicking materials successfully separated suspended oil and emulsified oil,with a maximum flux of 2086 Lm^(−2) h^(−1) and a separation efficiency of more than 99%.The proposed biopolymeric nanofibrous membranes use fish gelatin,which can be extracted from fish waste and has excellent biodegradability with excellent oil-water separation performance.In addition,polymer material processing,including membrane manufacturing and crosslinking,can be realized through eco-friendly processes.Therefore,fish skin-inspired biopolymeric membrane is expected to be a promising candidate for a sustainable and effective oil-water separation membrane in the future.

Micro/nano structured oleophobic agent improving the wellbore stability of shale gas wells

Through embedding modified nano-silica particles on the surface of polystyrene using the method of Pickering emulsion polymerization,a kind of nano/micro oleophobic agent named OL-1 was developed.The effects of OL-1 on the rock surface properties and its performance in inhibiting the oil phase imbibition into the rock were explored.The performance and mechanisms of OL-1 in improving the wellbore stability of shale gas wells were evaluated and analyzed.OL-1 could absorb on the surface of the shale core to form a membrane with a micro-nano two-stage roughness,making the surface energy of the core decrease to 0.13 mN/m and the contact angle of the white oil on the core surface increase from 16.39°to 153.03°.Compared with the untreated capillary tube,when immersed into 3#white oil,the capillary tube treated by OL-1 had a reversal of capillary pressure from 273.76 Pa to-297.71 Pa,and the oil imbibition height inside the capillary tube decreased from 31 mm above the external liquid level to 33 mm below the external liquid level.The amount of oil invading into the rock core modified by OL-1 decreased by 64.29%compared with the untreated one.The shale core immersed into the oil-based drilling fluids with 1%OL-1 had a porosity reduction rate of only 4.5%.Compared with the core immersed in the drilling fluids without OL-1,the inherent force of the core treated by 1%OL-1 increased by 24.9%,demonstrating that OL-1 could effectively improve the rock mechanical stability by inhibiting oil phase imbibition.

OLEOPHOBIC AND HYDROPHOBIC FEATURE EXPERIMENTS OF FLUORINATED HIGH DENSITY POLYETHYLENE

The surface performances of directly fluorinated high density polyethylene （HDPE） are studied with Fourier transform infrared （FT-IR） spectra, scanning electron microscopy （SEM） and contact angle （CA） system. The SEM images show that there is a three-layer structure called the reaction, virgin and boundary layer structure. The depth of fluorinated layer is 5.75 ~m with 1 h fluorination time and 7.86 b^m with 2 h. The depths are 5.46 /~m and 5.07 /~m when fluorine density is 2G and 1~/0, respectively. CA indicates that the HDPE surface property becomes more hydrophobic with the increasing water contact angle from 78.5~ to 104.5~. Oleophobic and hydrophobic features of HDPE are identified by comparison of mass change experiments. It is shown that the in- crement rate of fluorinated HDPE is much lower than that of un-fluorinated HDPE filled in neither distilled water nor jet fuel.

Wettability Control between Oleophobic/Superhydrophilic and Superoleophilic/Superhydrophobic Characteristics on the Modified Surface Treated with Fluoroalkyl End-Capped Oligomers/Micro-Sized Polystyrene Particle Composites

Fluoroalkyl end-capped vinyltrimethoxysilane-N,N-dimethylacrylamide cooligomer [RF-(CH2-CHSi(OMe)3)x-(CH2-CHC(=O)NMe2)y-RF;RF = CF(CF3)OC3F7: RF-(VM)x-(DMAA)y-RF] was synthesized by reaction of fluoroalkanoyl peroxide [RF-C(=O)O-O(O=)C-RF] with vinyltrimethoxysilane (VM) and N,N-dimethylacrylamide (DMAA). The modified glass surface treated with the cooligomeric nanoparticles [RF-(VM-SiO3/2)x-(DMAA)y-RF] prepared under the sol-gel reaction of the cooligomer under alkaline conditions was found to exhibit an oleophobic/superhydrophilic property, although the corresponding fluorinated homooligomeric nanoparticles [RF-(VM-SiO3/2)n-RF] afforded an oleophobic/hydrophobic property on the modified surface under similar conditions. RF-(VM-SiO3/2)n-RF/RF-(VM-SiO3/2)x-(DMAA)y-RF/PSt (micro-sized polystyrene particles) composites, which were prepared by the sol-gel reactions of the corresponding homooligomer and cooligomer in the presence of PSt particle under alkaline conditions, provided an oleophobic/superhydrophilic property on the modified surface. However, it was demonstrated that the surface wettability on the modified surface treated with the RF-(VM-SiO3/2)n-RF/RF-(VM-SiO3/2)x-(DMAA)y-RF/PSt composites changes dramatically from oleophobic/superhydrophilic to superoleophilic/superhydrophilic and superoleophilic/superhydrophobic characteristics, increasing with greater feed ratios (mg/mg) of the RF-(VM)n-RF homooligomer in homooligomer/cooligomer from 0 to 100 in the preparation of the composites. Such controlled surfac

3D打印聚乳酸膜及其油-水分离性能

采用3D(3-Dimension)打印技术制备了具有规则孔道结构且孔径可控的多孔聚乳酸(PLA)膜,然后以聚乙烯醇(PVA)为表面改性剂,利用氢键交联作用制备了PVA/PLA复合膜。当PLA膜基底填充率为70%时制备的PVA/PLA-70%复合膜的水下油接触角为165.9°,具有超疏油特性。在使用微量水润湿油-水分离膜条件下,PVA/PLA-70%复合膜的油-水分离实验结果表明:PVA/PLA-70%复合膜的油-水分离效率大于99%、水通量高达73.12 L/(m^(2)·s);油-水分离循环使用80次后,分离效率仍大于97%,且水通量稳定在56.10 L/(m^(2)·s),PVA改性PLA膜具有良好的循环稳定性。利用3D打印技术为制备可生物降解的油-水分离膜提供了新的研究方法。

兼具优异光学性能和疏水疏油性能的含氟聚降冰片烯二甲酰亚胺的制备与性能

针对聚降冰片烯材料的传统热性能提高改性策略会导致光学性能大大下降的问题,文中以全氟己基碘烷、对溴苯胺和纳迪克酸酐等原料设计合成了一种侧基带有对全氟己基苯结构的降冰片烯二甲酰亚胺单体,并将其通过开环易位聚合制备了一种新型含氟降冰片烯基均聚物(PNANPF6),以及合成了侧基分别为苯(PNANP)、对甲基苯(PNANPC1)、对三氟甲基苯(PNANPF1)、对己基苯(PNANPC6)4种结构相似的均聚物作为对照,通过核磁共振波谱和红外光谱表征证明了聚合物的成功制备。结果表明,在热性能和力学性能可基本保持的前提下,PNANPF6的水/正十二烷接触角相比PNANP提高了18°/26°;在400 nm/800 nm处的透光率相比PNANP提高了36%/22%。充分证明酰亚胺、苯环和全氟己基结构的引入可协同提高降冰片烯聚合物的光学性能和疏水疏油性能。为新型多功能降冰片烯聚合物的制备提供一条新思路。

超疏水-高疏油SiC膜的制备及性能

基于SiO_(2)粒子共混喷涂与浸渍方法,研发了一种在SiC膜上制备超疏水-高疏油表面的工艺。通过喷涂不同粒径的SiO_(2)颗粒,在SiC膜表面构造具有双疏性能的微纳双重粗糙结构,然后通过浸渍将十七氟癸基三甲氧基硅烷接枝至SiC膜表面,成功制备了具有超疏水-高疏油特性和优异自清洁性能的SiC膜。通过改变含氟量、粗糙度,分析了各参数对表面润湿性的影响。经改性后所得超疏水-高疏油SiC膜表面上水和正十六烷的静态接触角分别为152.6°和146.3°,滚动角分别为5.2°和10.2°,这归因于SiC膜表面的微纳结构和低表面能物质降低了其与其他物质的黏附力。在强酸和强碱溶液中,超疏水-高疏油SiC膜表现出稳定的双疏性。本研究为在无机膜上构建具有优异耐酸碱性的超疏水-高疏油表面提供了一种简便的工艺。

棉织物表面耐久超双疏涂层的制备方法及其性能

为实现超双疏棉织物的高效制备,将全氟癸基三甲氧基硅烷(PFDMS)与氨水和无水乙醇(EtOH)复配水解,通过一步浸渍法制备了耐久超双疏棉织物。采用扫描电子显微镜、X射线光电子能谱仪对织物的表面形貌及元素组成进行分析,探讨了PFDMS用量及水解时间对织物表面润湿性的影响,测试了织物表面超双疏涂层的稳定性、耐久性和自清洁性能。结果表明:当PFDMS与EtOH的体积比为3∶50时,不同水解时间整理的棉织物均具有超双疏特性,水解10 min时整理棉织物的水接触角高达157.2°±0.3°,油接触角为150.0°±1.4°;PFDMS整理后的棉织物表面引入了CF_(2)、CF_(3)基团,F、Si元素的含量分别为0.66%和3.37%;整理棉织物经10000次循环磨擦、600 min超声波洗涤、24 h紫外光老化、24 h酸碱溶液或有机溶剂浸泡后,仍然具有超疏水和疏油特性。该方法及工艺简单高效,所制备的超双疏棉织物在自清洁领域具有潜在的应用前景和价值。

水下超疏油P(NIPAm-co-TMSPMA)/SiO_(2)复合涂层的制备及性能

为制备具有水下超疏油性能的P(NIPAm-co-TMSPMA)/SiO_(2)复合涂层,通过自由基聚合制备聚合物P(NIPAm-co-TMSPMA),采用溶胶-凝胶法制备P(NIPAm-co-TMSPMA)/SiO_(2)复合溶液,采用浸渍提拉法制备P(NIPAm-co-TMSPMA)/SiO_(2)复合涂层。通过FTIR、^(1)H-NMR、GPC、热重分析、SEM、接触角仪、UV对聚合物及复合涂层进行测试分析。实验结果表明:随SiO_(2)质量分数的增加,亲水性逐渐降低,水下疏油性呈现先增大后降低的趋势;当SiO_(2)质量分数为30%时,水下油接触角为156°,涂层具有较低粘附力,表明复合涂层具有较大的水下疏油接触角和较低粘附力,表现出良好水下超疏油性能。蛋白质吸附实验结果表明:空白样品表面蛋白质吸附量为163μg/cm^(2),复合涂层表面蛋白质吸附量为82μg/cm^(2),表现出一定的抗蛋白质吸附性能。由于复合涂层具有良好的水下超疏油性、极低粘附力以及一定的抗蛋白质吸附性能,为其在生物医学领域上的应用提供了可能。

还原氧化石墨烯亲油疏水材料的制备及性能评价

石墨烯类材料作为理想的碳纳米材料具有三维网状空间结构、巨大的比表面积和良好亲油疏水性能,被广泛应用于增强高分子材料。介绍了氧化石墨烯发泡法制备吸油材料,即聚氨酯材料在发泡过程中加入氧化石墨烯(GO)改性剂,随后对其还原,制备还原氧化石墨烯亲油疏水材料,并进行了结构表征及室内评价,重点探讨了氧化石墨烯浓度对材料吸附性能的影响,材料亲油疏水性能以及静态、动态油水分离效率。同时,对比总结其他石墨烯改性吸油材料的优缺点及目前存在的问题,最后概括本方法制备吸油材料的技术优势,为GO/CNTs等纳米材料制备高附加值产品工业化提供参考。

表面疏油Al_(2)O_(3)陶瓷膜的制备及表征

以氨水和无水氯化铝为原料,采用溶胶-凝胶法在SiC基体上制备了Al_(2)O_(3)陶瓷膜,以氟碳表面活性剂Capstone FS-50为改性剂,通过真空浸渍法对所制备的Al_(2)O_(3)膜进行疏油改性。结果表明,制备的膜孔径分布均匀,表面无裂纹和针孔缺陷,Capstone FS-50改性前后膜通量和孔结构几乎不变。Capstone FS-50能均匀附载在Al_(2)O_(3)膜表面,使其展现出良好的疏油性能(表面接触角最大为130°),在温度低于200℃时,改性陶瓷膜仍具有较好的疏油性和良好的耐磨性能。

聚四氟乙烯膜的改性及应用研究进展

综述了国内近年来PTFE膜的不同改性方法,以及PTFE改性膜在亲水性、生物相容性、导电性和疏油性等方面的功能改进及应用研究进展,并指出了未来的研究方向。

化纤织物疏水疏油功能整理的发展概况

早期荷叶表面的拒水现象引起了人们极大的兴趣,研究人员基于荷叶效应不断模仿荷叶表面的微纳结构,以获得可以比拟荷叶的超疏水表面。将超疏水表面应用于化纤织物有着巨大的应用前景,基于荷叶效应,可以通过构筑粗糙纹理表面的方法制备超疏水表面,但有些液体悬浮在纹理表面的稳定性较差,因此适用性有限。通过化学方法合成的含氟整理剂能够降低材料的表面能,使材料对大部分表面能较高的液体具有抵抗作用,使用含氟整理剂整理是目前制备超疏水表面的主流方法。但不论是构筑粗糙表面还是使用含氟整理剂整理,都无法使超疏水表面在极端环境下保持较好的拒液效果。通过在材料表面构建自愈合体系可以获得具有长久拒液效果的自愈合材料,这种超疏水材料的表面在受到机械磨损或化学腐蚀时,受损部位会自愈,从而达到持续的拒液效果。本文主要以化纤织物为例综述了疏水疏油功能整理的方法,阐释了化纤织物的疏水疏油机理,探讨了化纤织物受到化学腐蚀、机械磨损时应如何保持拒液稳定性的问题,并对未来化纤织物疏水疏油功能整理的发展方向进行了展望。

阳离子分散松香胶/AKD乳液/壳聚糖联合提高麻浆与烟梗浆配抄滤嘴棒用纸的疏水疏油性能

以麻浆和烟梗浆为原料,抄造滤嘴棒用纸。通过浆内添加施胶剂〔阳离子分散松香胶和烷基烯酮二聚体(AKD)乳液〕和表面涂布壳聚糖的方法,提高滤嘴棒用纸的疏水疏油性能。探究施胶剂添加量和壳聚糖涂布量对滤嘴棒用纸防水性能、防油等级和物理性能的影响。研究结果表明:当浆内阳离子分散松香胶和AKD乳液添加量均为2%(相对绝干浆)时,滤嘴棒用纸的接触角为128.8°,60 s时滤嘴棒用纸的可勃值为24.30 g/m^(2);当壳聚糖涂布量为20 g/m^(2)时,滤嘴棒用纸的防油等级为12级。

Long-Lasting Filtration of Oily Water by Anti-Fouling Underwater Oleophobic Sand Particles

The produced water from the oilfield was purified with filter material and then injected back into the ground.The serpentine filter material was easy to harden with the increase in filtration amount,which affected the water quality.A superhydrophilic/underwater oleophobic serpentine filter material was successfully prepared by a simple method of coating modification,which exhibited long-lasting filtration of oily water,good filtration and anti-fouling properties,and resistance to harden.The film-forming material of the superhydrophilic/underwater oleophobic coating was composed of SiO_(2) particles with small size,which could completely and evenly cover the filter particle.The weight loss was only 7.6%after mechanical stirring for 90 min.Compared with the original filter material,the superhydrophilic/underwater oleophobic serpentine filter material showed a better anti-fouling ability and resistance to harden.The filtration of crude oil emulsion and oil slick sewage showed a better backwashing performance.After 35 cycles of continuous filtration of suspended solids in wastewater,the backwashing rate reached 78.4%.The results provided an effective method for the filtration of oily wastewater in the oilfield.

Nonswellable hydrogels with robust micro/nano-structures and durable superoleophobic surfaces under seawater

Hydrogels, composed mainly of water trapped in three dimensional cross-linked polymer networks, have been widely utilized to construct underwater superoleophobic surfaces. However, the swelling nature and instability of hydrogels under complex marine environment will weaken their underwater superoleophobicity. Herein, we synthesize structured poly （2-hydroxyethylmethacrylate） （PHEMA） hydrogels by using sandpaper as templates. The robust non-swelling of PHEMA hydrogel ensures that micro/nano-structures on the surface of PHEMA hydrogels can be well maintained. Moreover, when roughness Ra of about 3-4 bun, the surface has superior oil-repellency. Additionally, even after immersing in seawater for one-month, their breaking strength and toughness can be well kept. The non-swellable hydrogels with long-term stable under seawater superoleophobicity will promote the development of robust superoleophobic materials in marine antifouling coatings, biomedical devices and oil/water separation.

Hydrophilic/underwater superoleophobic graphene oxide membrane intercalated by TiO2 nanotubes for oil/water separation

Membrane technology for oil/water separation has received increasing attention in recent years. In this study, the hydrophilic/underwater superoleophobic membrane with enhanced water permeability and antifouling ability were fabricated by synergistically assembling graphene oxide （GO） nanosheets and titanium dioxide （TiO2） nanotubes for oil/water separation. GO/TiO2 membrane exhibits hydrophilic and underwater superoleophobic properties with water contact angle of 62° and under water oil contact angle of 162.8°. GO/TiO2 membrane shows greater water permeability with the water flux up to 531 L/ （m^2·h·bar）, which was more than 5 times that of the pristine GO membrane. Moreover, GO/TiO2 membrane had excellent oil/water separation efficiency and anti-oil-fouling capability, as oil residual in filtrate after separation was below 5 mg/L and flux recovery ratios were over 80%.The results indicate that the intercalation of TiO2 nanotubes into adjacent GO nanosheets enlarged the channel structure and modified surface topography of the obtained GO/TiO2 membranes, which improved the hydrophilicity, permeability and anti-oil-fouling ability of the membranes, enlightening the great prospects of GO/TiO2 membrane in oil-water treatment.