Fabrication,characterization, and performance evaluation of polyethersulfone/TiO2 nanocomposite ultrafiltration membranes for produced water treatment

In the present work, development of neat and nanocomposite polyethersulfone membranes composed of TiO₂ nanoparticles is presented. Membranes are fabricated using nonsolvent phase inversion process with the objective of improving antifouling, hydrophilicity, and mechanical properties for real and synthetic produced water treatment. Membranes are characterized using scanning electron microscopy, Fourier‐transform infrared, contact angle, porosity measurement, compaction factor, nanoparticles stability, and mechanical strength. The performance of prepared membranes was also characterized using flux measurement and oil rejection. Fourier‐transform infrared spectra indicated that noncovalence bond formed between Ti and polyethersulfone chains. The contact angle results confirmed the improved hydrophilicity of nanocomposite membranes upon addition of TiO₂ nanoparticles owing to the strong interactions between fillers and water molecules. The increased water flux for nanocomposite membranes in comparison with neat ones can be due to coupling effects of improved surface hydrophilicity, higher porosity, and formation of macrovoids in the membrane structure. The membrane containing 7 wt% of TiO₂ nanoparticles was the best nanocomposite membrane because of its high oil rejection, water flux, antifouling properties, and mechanical stability. The pure water flux for this membrane was twice greater than that of neat membrane without any loss in oil rejection. The hydrophilicity and antifouling resistance against oil nominates developed nanocomposite membranes for real and synthetic produced water treatment applications with high performance and extended life span.     

仿生沉积法制备水下低气体黏附透明材料

透明材料常用于水下设备中,而聚合物透明材料多较为疏水,在水下易黏附气泡,影响其光学性能.利用多巴胺(DA)和聚乙烯亚胺(PEI)共沉积技术,在多种透明聚合物材料表面构建了亲水/水下超疏气涂层.结果表明,聚多巴胺(PDA)与PEI可通过Michael加成或Schiff碱反应在此类材料表面形成亲水交联网络,显著提高其表面亲水性.表现为水接触角显著降低,而水下气接触角显著提高(140?),气泡在材料表面的黏附力显著下降.沉积时间在6 h以下时,XPS和椭圆偏振测试的结果表明,虽然所选用的透明材料表面沉积量和沉积厚度随时间有所上升,但其透光性不会受到显著影响.该方法具有较强的普适性,可用于多种水下气体黏附性较强的透明高分子材料,如聚苯乙烯(PS)、聚对苯二甲酸乙二醇酯(PET)、聚甲基丙烯酸甲酯(PMMA)、聚丙烯(PP)和聚酰亚胺(PI)等.同时,该方法形成的涂层的长期稳定性也较好,材料在水中浸泡振荡10天之后仍能保持较好的抗气泡黏附能力.该方法适用于如潜水艇舷窗、护目镜、水下光学镜头及其防护罩等水下设备中.     

Fabrication of blend hydrophilic polyamide imide (Torlon®)-sulfonated poly (ether ether ketone) hollow fiber membranes for oily wastewater treatment

Blend hydrophilic polyamide imide (PAI)-sulfonated poly (ether ether keton) (SPEEK) hollow fiber membranes were fabricated for oil-water emulsion separation. The structure and performance of the membranes were examined by FESEM analysis, N₂ permeation, overall porosity, collapsing pressure, water contact angle, pure water flux, molecular weight cutoff (MWCO), and oil rejection tests. By studying ternary phase diagrams of polymer/solvent-additive/water system, the higher phase-inversion rate was confirmed for the solutions prepared at higher PAI/SPEEK ratio. A more open structure with larger finger-likes was observed by increasing PAI/SPEEK ratio. Mean pore size of 81 nm, overall porosity of 79% and water contact angle of 58° were obtained for the improved membrane prepared by PAI/SPEEK ratio of 85/15. Increasing SPEEK ratio resulted in lower mechanical stability in terms of collapsing pressure. Pure water flux of about 2.5 times of the plain PAI membrane was found for the improved membrane. MWCO of 460 kDa was found for the improved blend membrane. From oil rejection test, all the membranes demonstrated an oil rejection of over 95%. The improved membrane showed a lower rate of permeate flux reduction compared to the plain membrane which was related to the smaller fouling possibility. Less fouling resistance of the improved membrane was related to the higher flux recovery ratio (about 92%). For all the membranes, the dominant fouling mechanism was found to be the cake filtration. The improved PAI-SPEEK hollow fiber membranes was found to be practical for ultrafiltration of oily wastewaters.     

Preparation,properties, and application of polypropylene micro/nanofiber membranes

Nanofiber membranes have huge potential applications in many areas due to their unique properties. However, the thermoplastic micro/nanofiber membranes were rarely reported. In this paper, polypropylene (PP) nanofibers were prepared by melt extrusion of immiscible blends of PP, cellulose acetate butyrate (CAB), and subsequent removal of the CAB matrix. The wet‐laid application was used to make PP nanofiber membranes and PP‐g‐MAH/nonwoven micro/nanofiber membrane. The properties of membranes including morphology, apparent density, porosity, contact‐angle, pore size distribution, and water flux were characterized. The results showed that the consequent membranes were provided with optimistic porosity and pore size distribution. Moreover, they were all with high pure water fluxes, which were superior to that of PP microporous membrane. They performed an excellent separation performance of TiO₂ suspension and dyeing wastewater. The work revealed this method could be an efficient one to make thermoplastic polymer micro/nanofiber membranes, and they would have a brilliant potential application for water treatment. Copyright © 2010 John Wiley & Sons, Ltd.     

Effects of dip coating parameters on the morphology and transport properties of cellulose acetate–ceramic composite membranes

This work presents the fabrication of cellulose acetate (CA)–ceramic composite membranes using dip coating technique. Ceramic supports used in this work were prepared from kaolin with an average pore size of 560 nm and total porosity of 33%. The dip coating parameters studied experimentally were the concentration of CA solution (varying from 2 wt% to 8 wt%) in acetone and dipping time (varying from 30 s to 150 s). The fabricated composite membranes were characterized using scanning electron microscope, gas permeation, pure water flux and ultrafiltration (UF) experiments using bovine serum albumin (BSA). It was observed that the membrane prepared with 2 wt% and 4 wt% CA were suitable for microfiltration applications and those with 6 wt% and 8 wt% were for ultrafiltration applications. Theoretical investigation was conducted to know the macroporous and mesoporous structure of the prepared membranes using Knudsen and viscous permeability analysis of air. A resistance in series model was applied to identify different resistances responsible for the flux decline. Phenomenological models were proposed to illustrate the dependency of hydraulic resistance of membrane on the structural parameters such as average pore size, effective porosity as well as dip coating parameters like dipping time and concentration of CA. It was found that, the growth rate of CA film on the ceramic support followed exponential growth law with respect to dipping time. The total hydraulic resistance of the membrane was evaluated to be inversely proportional to the ratio of pore sizes of top layer and ceramic support. The resistance due to the CA film was found to be depended to the order of 1.73 with respect to concentration of CA. An increase in the concentration of CA was found to be more effective than dipping time to reduce the membrane pore size.     

Cellulose acetate nanocomposite ultrafiltration membranes tailored with hydrous manganese dioxide nanoparticles for water treatment applications

Hydrous manganese dioxide (HMO) nanoparticles incorporated cellulose acetate (CA) composite ultrafiltration (UF) membranes are prepared with the aim of improving the water permeation and BSA contaminant removal. The HMO nanoparticles are synthesized from manganese ion and characterized by FT‐IR, XRD, and FESEM. The effect of variation of HMO on CA membranes is probed using FT‐IR, EDAX, contact angle, SEM, and AFM analysis to demonstrate their chemical functionality, hydrophilicity, and morphology. CA/HMO membranes are showing the enhancement in pure water flux (PWF), water uptake, porosity, hydrophilicity, fouling resistance, BSA rejection, and flux recovery ratio (FRR). CA‐1 membrane displayed higher PWF (143.6 Lm²h^?1), BSA rejection (95.9%), irreversible fouling (93.3%), and FRR (93.3%). Overall results confirmed that the CA/HMO nanocomposite UF membranes overcome the bottlenecks and shows potential for water treatment applications.     

四乙基氢氧化铵改性聚偏氟乙烯接枝聚丙烯酸油水分离膜的制备

使用四乙基氢氧化铵(TEAH)液相本体改性聚偏氟乙烯(PVDF), 以过氧化苯甲酰(BPO)为引发剂, 将丙烯酸(AA)接枝到改性PVDF骨架上, 合成了聚偏氟乙烯接枝聚丙烯酸(PVDF-g-PAA)共聚物, 通过浸没沉淀法制备了PVDF-g-PAA亲水性油水分离膜. 通过傅里叶变换红外光谱(FTIR)、 扫描电子显微镜(SEM)和过滤试验分析了膜的结构和分离性能. 研究了不同接枝条件对PVDF-g-PAA膜接枝率的影响. 同时, 通过膜接枝率与膜表面接触角的关系确定最佳接枝条件. 结果表明, TEAH使PVDF脱去HF产生碳碳双键且PAA接枝到改性的PVDF骨架上, 膜内外孔隙分布均匀; PVDF-g-PAA膜的接触角随着接枝率的提高而降低. 接枝单体AA含量为45%, 接枝温度为85 ℃, 接枝4 h制备的PVDF-g-PAA膜的接枝率为20.1%, 孔隙度为65.3%, 平均孔径为78.0 nm, 接触角为57.5°, 且在60 s内接触角降至14.3°; 纯水通量提高到571.33 L/(m²·h), 截留率和水通量恢复率分别达到94.3%和88.7%, 且通量衰减率仅为9.8%. 与纯PVDF膜相比, PVDF-g-PAA膜的分离性能显著提高.     

Bio‐inspired method to fabricate poly‐dopamine/reduced graphene oxide composite membranes for dyes and heavy metal ion removal

Due to the narrow layer spacing, graphene oxide (GO) composite membrane usually exhibits a relatively low water flux in the process of wastewater treatment. In this study, GO was reduced to reduced graphene oxide through a bio‐inspired method, which was functionalized modified by poly‐dopamine (PDA). Then a series of PDA/reduced graphene oxide sheet films were prepared by vacuum filtration on the surface of cellulose acetate membrane (under the pressure of −0.1 MPa). The result indicated that the novel membranes had an excellent stability owing to the cross‐link of PDA. In addition, the hydrophilicity of membrane was increased significantly after PDA modification, which presented a superior water flux than pure GO composite membrane. More importantly, as‐prepared membranes were successfully applied for the removal of dyes (including Congo red, methylene blue, and rhodamine B) and heavy mental ion (Cu(II)) from simulated wastewater. This work might provide a new method for preparation and application of GO composite membranes.     

Preparation and characterization of modified polyphenylsulfone membranes with hydrophilic property for filtration of aqueous media

In the present research, the low water flux of polyphenylsulfone membranes was addressed, and a novel improvement in their water permeation and fouling resistance was achieved using polyethylene glycol (PEG) as the hydrophilic additive. Scanning electron microscopy and field emission scanning electron microscopy, atomic force microscopy, attenuated total reflection Fourier‐transform infrared spectroscopy, thermogravimetric analysis, and tensile test were applied for the investigation of membrane morphology, surface topography, surface chemical structure, thermal stability, and mechanical properties, respectively. Moreover, the relative hydrophilicity/hydrophobicity of the membranes was assessed via determination of membrane water uptake capacity and water contact angle. The membrane performance was studied and compared by determination of pure water flux and filtration of canned beans production wastewater as well as bovine serum albumin solution. The filtration results indicated a remarkable pure water flux and 100% turbidity rejection provided by the polyphenylsulfone/PEG 20 000 membrane. In addition, it was confirmed that the amount of residual PEG within the membrane was increased with increasing PEG molecular weight and concentration.     

Versatility of hydrophilic and antifouling PVDF ultrafiltration membranes tailored with polyhexanide coated copper oxide nanoparticles

Hydrophilic poly(vinylidene fluoride) (PVDF) nanocomposite ultrafiltration (UF) membranes with excellent antifouling and antibiofouling characteristics are fabricated by employing polyhexanide coated copper oxide nanoparticles (P–CuO NPs). The presence of P–CuO NPs is played a significant role in altering the PVDF membrane matrix and probed by XRD, FTIR, FESEM and contact angle analysis. The PVDF/P–CuO nanocomposite membranes exhibited an outstanding antifouling performance indicated by the superior pure water flux, effective foulant separation and maximum flux recovery ratio during UF experiments as a result of the formation of the hydrophilic and more porous membrane due to the uniform distribution of P–CuO NPs. Particularly, the PVDF/P–CuO-3 membrane showed higher PWF of 152.5 ± 2.4 lm⁻²h⁻¹ and porosity of 64.5% whereas the lower contact angle of 52.5°. Further, it showed the higher rejection of 99.5 and 98.4% and the flux recovery ratio of 99.5 and 98.5% respectively for BSA and HA foulants, demonstrated its increased water permeation, foulant separation and antifouling behavior. Further, the decent antibacterial activity is showed by the PVDF/P–CuO nanocomposite membranes with the formation of halo-zone around the membrane when exposed to the bacterial medium demonstrated that, by this process an antibacterial water treatment membrane can be developed by simple phase inversion technique with good membrane stability.     

Surface roughness and hydrophilicity enhancement of polyolefin‐based membranes by three kinds of plasma methods

The introduction of antibacterial property, conductivity, wettability and antithrombogenicity into polyolefin‐based membranes has evoked much attention, which can be achieved by coating hydrophilic polymers. Therefore, it is necessary to modify the roughness and hydrophilicity of polyolefin‐based membranes to enhance the coating ability. In this paper, three kinds of plasma methods, including inductively coupled (ICP) plasma, radio frequency low pressure (RFP) plasma and atmospheric dielectric barrier discharge (DBD) plasma, were used to modify the surface of the polyethylene (PE), polypropylene (PP) and polyester‐polypropylene (PET–PP) membranes. The surface roughness of the plasma‐modified PE, PP and PET–PP films was investigated by scanning electron microscopy (SEM) and atomic force microscope (AFM). The polar functional groups of films were observed by energy dispersive spectrometer (EDX) and X‐ray photoelectron spectroscopy (XPS). Besides, the hydrophilicity of the plasma‐modified PE, PP and PET–PP films was evaluated by water contact angle measurement. It was found that the surface roughness and hydrophilicity of plasma‐modified PE, PP and PET–PP films increased with the generation of oxygen‐containing functional groups (i.e. C―O, and C?O). The PET–PP membranes were treated by RFP plasma at different processing powers and times. These results indicated that plasma is an effective way to modify films, and the treatment time and power of plasma had a certain accumulation effect on the membranes' hydrophilicity. As for the roughness and hydrophilicity, the DBD plasma modifies the PE film, which is the optimum way to get the ideal roughness and hydrophilicity. Copyright © 2015 John Wiley & Sons, Ltd.     

聚多巴胺/聚乙烯亚胺共沉积中间层增强薄膜复合正渗透膜性能

以聚多巴胺/聚乙烯亚胺(PDA/PEI)共沉积于三醋酸纤维素(CTA)多孔支撑膜表面形成中间层,再结合界面聚合法获得聚酰胺薄膜,构建了PDA/PEI共沉积中间层改性薄膜复合(TFC)正渗透(FO)膜.通过傅里叶变换衰减全反射红外光谱法、扫描电子显微镜、原子力显微镜、溶质截留法、水接触角仪等研究了PDA/PEI共沉积中间层对CTA膜和TFC膜的表面结构和性质的影响.研究结果表明,PDA/PEI共沉积使得CTA膜表面变得更为平滑,表面孔径减小至(30.0±4.1) nm,且表面孔径分布趋于均一.同时,在PDA/PEI共沉积改性CTA膜表面界面聚合得到的聚酰胺层呈现出更均匀的叶片状结构和优异的亲水性.基于此,具有PDA/PEI共沉积中间层的TFC正渗透膜显著提高了水通量(FO模式:(7.1±2.3) L/(m^2·h)),较空白TFC膜提升了57.6%.同时,中间层改性TFC膜具有更低的反向盐通量(FO模式:1.4±0.1 g/(m^2·h))和"净盐通量"(FO模式:(0.2±0.06) g/L),与空白TFC膜相比分别下降了83.9%和90.6%.说明PDA/PEI共沉积中间层不仅能有效提升TFC正渗透膜的水渗透性,而且大幅提升了膜的截盐性和渗透选择性.     

Synthesis and characterization of hydrophilicity-controlled poly(arylene ether sulfone) copolymers with phenolphthalein-based carboxylic acid groups for separation membrane applications

Abstract

Hydrophilicity-controlled poly(arylene ether sulfone) copolymers with phenolphthalein-based carboxylic acid groups (PES-COOH-X) were synthesized via direct copolymerization by adjusting the feed molar ratio. The chemical structures of the obtained copolymers were confirmed by ¹H nuclear magnetic resonance (NMR) spectroscopy. The copolymers showed good solubility in common aprotic solvents and exhibited excellent mechanical properties. The water contact angles of the obtained copolymers could be reduced by approximately 52% from 92.1° to 44.2° with increasing content of phenolphthalein-derived monomer, 2-[bis(4-hydroxyphenyl)methyl] benzoic acid (PPH-COOH), in the feed molar ratio. A series of PES-COOH-X membranes was prepared via a conventional immersion precipitation phase inversion method. The effects of the monomer feed molar ratio on the morphology, hydrophilicity, pure water flux, and water uptake of the prepared membranes were investigated. The results showed that the pure water flux of the PES-COOH-X membranes was significantly enhanced by almost a factor of two as compared to the pristine PES membrane. From the water contact angle data, it was identified that the hydrophilicity of the membranes was increased rapidly with increasing PPH-COOH content in the membranes. These hydrophilicity-controlled poly(arylene ether sulfone) copolymers may be considered as good candidates for separation membrane materials.     

HBPE-g-PVDF/PVDF blend nanofiltration membrane: preparation and characterization

Hyperbranched polyester-grafted poly(vinylidene fluoride) (HBPE-g-PVDF) was synthesized and used as additive in preparation of PVDF blend membranes. HBPE-g-PVDF copolymer was characterized with FTIR and TGA techniques. The prepared membranes were also characterized with SEM, AFM and contact angle measurement. The performance of prepared membranes as nanofiltration membrane was studied by pure water flux (PWF), salt rejection, dynamic and static fouling tests. The results showed that hydrophilicity of prepared membranes greatly increased after blending, and their pore size and pore size distribution and so PWF of blend membranes increased.     

Surface hydrophilization for polypropylene microporous membranes: A facile interfacial crosslinking approach

A hydrophilic surface is very important for hydrophobic separation membranes such as polypropylene microporous membranes (PPMMs). In this work a facile and effective method, interfacial crosslinking combined with pretreatment by dielectric barrier discharge plasma at atmospheric pressure, was developed for endowing PPMMs with a hydrophilic and charged surface. Poly(N,N-dimethylaminoethyl methacrylate) (PDMAEMA) and p-xylylene dichloride were selected for quaternization crosslinking to form a positively charged coating layer, which was characterized with FT-IR/ATR, XPS, and FESEM. Water contact angle and pure water flux measurements were conducted to evaluate the surface hydrophilicity. The influence of surface charges on protein filtration was also investigated. It is found that the mass gain of interfacial crosslinking increases almost linearly with increasing the PDMAEMA concentration from 0.5 to 10 g/L. The crosslinking degree is larger than 80% according to the XPS results, ensuring the stability of the crosslinking layer. The surface hydrophilicity is demonstrated by the sharp decrease of water contact angle from 145° to 20°. The pure water flux also increases 3 times under the optimized conditions. Furthermore, the results of protein filtration suggest that these highly hydrophilic and charged surfaces can effectively resist the fouling of proteins.     

Nanostructured polyethersulfone membranes for dye and protein separation: Exploring antifouling role of holmium (III) molybdate nanosheets

Nanostructured polymer membranes are nowadays of crucial importance in achieving antifouling properties. Nanomaterials with tunable composition, size, and morphology, surface modification and functionality offer unprecedented opportunities for efficient wastewater treatment. In this work, the effect of holmium (III) molybdate (Ho₂MoO₆) nanomaterial as a new nanofiller on preparation of nanostructured polyethersulfone (PES) mixed matrix membranes was examined in terms of hydrophilicity, membrane morphology, permeability, dye and protein separation and antifouling property. The Ho₂MoO₆ nanosheets were synthesized and characterized by FTIR, XRD, and FESEM and used in different amounts in PES matrix. The pore size and the membrane porosity increased with Ho₂MoO₆ loading. The nanocomposite membranes showed enhancement in hydrophilicity, antifouling properties, dye rejection and permeability. The remarkably pure water flux (195 L/m²h at 3 bar) and 92.3% flux recovery after bovine serum albumin (BSA) filtration were obtained for the membrane mixed with 2 wt% Ho₂MoO₆ compared to 95 L/m²h and 75.2% obtained for the bare PES, respectively. Moreover, significantly high rejection of Acid Red 125 (95 ± 1%) was achieved. Thus, the experimental results established the potential efficiency of the novel nanocomposite membrane for the separation applications.     

Preparation and characterization of TiO2/Pebax/(PSf‐PES) thin film nanocomposite membrane for humic acid removal from water

New thin film composite (TFC) membrane was prepared via coating of Pebax on PSf‐PES blend membrane as support, and its application in wastewater treatment was investigated. To modify this membrane, hydrophilic TiO₂ nanoparticles were coated on its surface at different loadings via dip coating technique. The as‐prepared membrane was characterized using Fourier transform infrared spectroscopy, scanning electron microscopy (SEM), field emission SEM, and contact angle analysis. The Fourier transform infrared spectroscopy analysis and surface SEM images indicated that TiO₂ was successfully coated on the membrane surface. In addition, the results stated that the hydrophilicity and roughness of membrane surface increased by addition of TiO₂ nanoparticles. Performance of TFC and modified TFC membranes was evaluated through humic acid removal from aqueous solution. Maximum permeate flux and humic acid rejection were obtained at 0.03 and 0.01 wt% TiO₂ loadings, respectively. Rejection was enhanced from 96.38% to 98.92% by the increase of feed concentration from 10 to 30 ppm. Additionally, membrane antifouling parameters at different pressures and feed concentration were determined. The results indicated that surface modification of membranes could be an effective method for improvement of membrane antifouling property.     

The effect of heat treatment of PES and PVDF ultrafiltration membranes on morphology and performance for milk filtration

The flat sheet polyethersulfone (PES) and poly(vinylidene fluoride) (PVDF) membranes were prepared by immersion precipitation technique. The influence of hot air and water treatment on morphology and performance of membranes were investigated. The membranes were characterized by AFM, SEM, cross-flow filtration of milk and fouling analysis. The PES membrane turns to a denser structure with thick skin layer by air treatment at various temperatures during different times. This diminishes the pure water flux (PWF). However the milk permeation flux (MPF) was considerably improved at 100 °C air treatment for 20 min with no change in protein rejection. The smooth surface and slight decrease in surface pore size for air treated PES membrane at 100 °C compared to untreated membrane may cause this behavior for the membrane. The water treatment of PES membranes at 55 and 75 °C declines the PWF and MPF and increases the protein rejection. This is due to slight decrease in membrane surface pore size. The treatment of PES membrane with water at higher temperature results in a porous structure with superior performance. The fouling analysis of 20 min treated membrane indicates that the surface properties of 100 °C air treated and 95 °C water treated PES membranes are improved compared to untreated membrane. The SEM observation depicts that the morphology of air and water treated PVDF membranes was denser and smoother with increasing the heat treatment temperature. The 20 min air treated PVDF membranes at 100 °C and water treated at 95 °C exhibited the highest performance and antifouling properties.     

Excellent hydrophilic and anti-bacterial fouling PVDF membrane based on ag nanoparticle self-assembled PCBMA polymer brush

A silver nanoparticles-poly(carboxybetaine methacrylate)(AgNPs-PCBMA) nanocomposite was prepared on poly(vinylidene fluoride)(PVDF) membrane surface to improve its hydrophilicity and antifouling properties. Firstly, the PVDF membranes were grafted by PCBMA via physisorbed free radical grafting technique. Then Ag+ coordinated to the carbonyl group on PCBMA andsubsequently was reduced to silver nanoparticles. The hydrophilicity of the PVDF-gPCBMA/Ag membrane wasenhanced with the increasing fixed degree(FD) of AgNPs, and the original water contact angle of membrane was reduced to 33.97°. Additionally, water flux recovery ratio(FRR) andbovine serum albumin(BSA) rejection ratio of PVDF-g-PCBMA/AgNPs membrane wereimproved from 52% to 93.32% and 28.12% to 91.12%, respectively. Further, the PVDF-g-PCBMA/AgNPs membranes exhibited the more pronounced inhibition zone. The study demonstrated that compared with pure AgNPs or the PCBMA polymer brush, the synergistic effect of PCBMA and AgNPs made PVDF membranes havebetter hydrophilicity and anti-bacterialperformances.     

Easy‐to‐fabricate thin‐film coating on PDMS substrate with super hydrophilicity and stability

With the fast expansion of microfluidic applications, stable, and easy‐to‐fabricate PDMS surface coating with super hydrophilicity is highly desirable. In this study, we introduce a new kind of copolymer‐based, single‐layer thin‐film coating for PDMS. The coating can exist in air at room temperature for at least 6 months without any noticeable deterioration in the super hydrophilicity (water contact angle ～7°), resistance of protein adsorption, or inhibition of the EOF. In addition, this coating enables arbitrary patterning of cells on planar surfaces.