Preparation and characterization of polyzwitterionic hydrogel coated polyamide-based mixed matrix membrane for heavy metal ions removal

A novel polyzwitterionic hydrogel coated mixed matrix membrane (MMM) was successfully prepared, characterized and used for Cu²⁺, Mn²⁺, and Pb²⁺ heavy metal ions removal from water. Hydrophilic and porous covalent organic framework (COF) nanoparticles (NP) as filler were synthesized from melamine and terephthalaldehyde, and then incorporated into polyamide (PA) thin film composite (TFC) membrane. The hydrogel coating was applied by using a tailored cross-linkable polymer system in combination with concentration polarization enabled cross-linking. The effects of COF NP loading into PA layer and polyzwitterionic hydrogel coating on the membrane morphology and separation performance were studied using different analyses. The MMM prepared with a COF NP loading of 0.02 wt/wt% in the hexane dispersion used for NP deposition during PA layer formation (leading to 0.42 g/m²) exhibited an increased pure water permeability of around 200% compared with the neat PA TFC membrane while the Mn²⁺ ion rejection maintained above 98%. Scanning electron microscopy surface images and zeta potential profiles showed that the hydrogel was successfully deposited on the membrane surface. Furthermore, the hydrogel coating could decrease net surface charge of membranes but did not significantly influence the heavy metal ions rejections under nanofiltration conditions. The results of filtration experiment with protein solution indicated that the hydrogel coated membranes exhibited superior antifouling property, as shown by higher flux recovery ratio after washing with water, compared with neat PA TFC membrane and not coated MMM, respectively.     

Nanocomposite hollow fiber nanofiltration membranes: Fabrication,characterization, and pilot-scale evaluation for surface water treatment

Thin-film nanocomposite (TFN) membranes were fabricated by interfacial polymerization of a polyamide (PA) layer on the shell side of hollow fiber membrane supports. TiO₂ nanoparticle loadings in the thin-film layer were 0.01, 0.05, and 0.20 wt %. Nanoparticle-free PA thin-film composite (TFC) membranes served as the comparative basis. The TFN membranes were characterized in terms of the chemical composition, structure, and surface properties of the separation layer. Incorporating nanoTiO₂ improved membrane permeability up to 12.6-fold. During preliminary laboratory-scale evaluation, TFN membranes showed lower salt rejection but higher TOC rejection in comparisons with the corresponding values for TFC controls. Based on the performance in lab-scale tests, TFN membranes with 0.01 wt % nanoTiO₂ loading were selected for an evaluation at the pilot scale with synthetic surface water as the feed. While the permeate flux during long-term pilot-scale operation gradually decreased for TFC membranes, TFN membranes had a higher initial permeate flux that gradually increased with time. The TOC rejection by TFN and TFC membranes was comparable. We conclude that TFN membranes show promise for full-scale surface water treatment applications. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48205.     

Enhanced chlorine-resistant and low biofouling reverse osmosis polyimide-graphene oxide thin film nanocomposite membranes for water desalination

The effect of graphene oxide (GO) loading (0.03, 0.06, 0.09, 0.12, and 0.30 wt%) in the aqueous phase on the performance of reverse osmosis (RO) polyimide (PI) thin film composite (TFC) membrane was investigated. TFC and thin film nanocomposite (TFN) membranes were produced through interfacial polymerization and the imide linkage was confirmed by attenuated total reflection Fourier transform infrared spectroscopy. The spongy-like structure with vertical fingers of RO PI-GO TFN membranes was explored by top-surface and cross-sectional field emission scanning electron microscope (FE-SEM). The roughness of the membranes was determined. All PI-GO TFN membranes exhibited enhanced desalination performance in comparison with PI membranes. Samples with 0.06 wt% GO performed the best with a water flux of 31.80 L/m²/h, salt rejection of 98.8%, and very good antibiofouling properties. This hydrophilic membrane displayed significantly enhanced chlorine-resistance with water flux of 36.3 L/m²/h and salt rejection of 98.5%. This work provides a promising start for designing rapid water permeation PI-GO TFN membranes in water desalination.     

In-situ generated ZnO nanoparticles for enhanced performance of thin film nanocomposite membrane in forward osmosis process

This work developed a novel approach to the in-situ synthesis of ZnO nanoparticles to modify the polysulfone (PSf) porous membrane substrate. The zinc acetate was added to the casting solution, and ZnO nanoparticles were synthesized during phase inversion. The non-solvent pH and zinc acetate concentration controlled the ZnO synthesis and loading. Their effect on the substrates properties in terms of morphology, hydrophilicity and porosity was studied thoroughly. The result shows that the ZnO nanoparticles was not formed in acidic pH, while ZnO nanoparticles with size of 20 nm could be easily formed in basic pH. The successful synthesis of ZnO nanoparticles was investigated using FTIR and EDX analysis. The EDX images verify that in-situ synthesis led to a more uniform dispersion than conventional incorporation method. Then the effect of ZnO loading on the interfacial reaction and polyamide (PA) structure was investigated. SEM images verify the successful synthesis of a uniform and defect-free PA thin film on ZnO modified substrates. FO performance results show an enhancement in water flux and salt rejection as a result of ZnO incorporation in thin film nanocomposite (TFN) membranes, where TFN 1 wt.% in-situ membrane showed 40% higher water flux than the control TFC membrane. The porous and hydrophile substrate in TFN 1 wt.% in-situ membrane is responsible for improved separation performance. These modified membranes displayed uniform dispersion of ZnO nanoparticles within substrates, confirming that this method could effectively restrain the aggregation of the nanoparticles.     

A solvent-resistance OTS/PDA/O-PASS composite membrane for water-in-oil emulsions separation

Water-in-oil emulsions separation plays a critical role in industrial wastewater treatment. Membrane technology has attracted much interest in water-in-oil emulsions separation field for its excellent separation performance and facile processing method. However, versatile membrane with better solvent-resistance is still absent in chemical industry. In this work, oxidized polyarylene sulfide sulfone (O-PASS) membrane was severed as substrate, on which a hydrophobicity surface was built via coating of octadecyltrichlorosilane (OTS). And polydopamine (PDA) layer was employed and acted as connector between OTS and O-PASS membrane due to its abundant active hydroxyl group. The maximum water contact angle was 132.6° indicating good hydrophobicity of the membrane. Finally, the OTS/PDA/O-PASS composite membranes showed good separation performance for corrosive emulsions: the rejection and flux were 93.0% and 10.0 L/m²h for water-in-dichloromethane emulsions, and the rejection and flux were 92.3% and 34.6 L/m²h for water-in-n-hexane emulsions. The OTS/PDA/O-PASS composite membrane is a new candidate membrane for water-in-oil emulsions separation. In addition, the superior performance of the composite membrane under harsh environment conditions ensures its usefulness in resistance aggressive solvent.     

Sublayer assisted by hydrophilic and hydrophobic ZnO nanoparticles toward engineered osmosis process

Hydrophilic and hydrophobic polyethersulfone (PES)-zinc oxide (ZnO) sublayers were prepared by loading of ZnO nanoparticles into PES matrix. Both porosity and hydrophilicity of the hydrophilic sublayer were increased upon addition of hydrophilic ZnO, while these were decreased for the hydrophobic sublayer. In addition, the results demonstrated that the hydrophilic membrane exhibited smaller structural parameter (S value or S parameter or S), which is beneficial for improving pure water permeability and decreasing mass transfer resistance. In contrast, a higher S parameter was obtained for the hydrophobic membrane. With a 2M NaCl as DS and DI water as FS, the pure water flux of hydrophilic TFN0.5 membrane was increased from 21.02 L/m² h to 30.06 L/m² h and decreased for hydrophobic TFN0.5 membrane to 14.98 L/m² h, while the salt flux of hydrophilic membrane increased from 10.12 g/m² h to 17.31 g/m² h and decreased for hydrophobic TFN0.5 membrane to 3.12 g/m² h. The increment in pure water permeability can be ascribed to reduction in S parameter, which resulted in reduced internal concentration polarization (ICP). The current study provides a feasible and low cost procedure to decrease the ICP in FO processes.     

Synthesis of polydopamine‐mediated PP hollow fibrous membranes with good hydrophilicity and antifouling properties

Membrane fouling remains a major barrier to membrane separation, particularly obvious in polymer membranes. Dopamine (DA) is of great value as a precursor for conjugation hydrophilic molecules. In this study, PP hollow fibrous membranes were first modified by DA to form a layer of polydopamine (PDA) coating. Then taurine and glycidol were introduced respectively with assisted by PDA reactive layer, the prepared membranes corresponding to PP‐T and PP‐G membranes, respectively. PP and the modified PP membranes were confirmed by a thorough membrane characterization of ATR‐FTIR, XPS, and FESEM measurements. The hydrophilic properties and permeability were measured by water contact angle (WCA) and permeation flux test. BSA was used to as model protein to evaluate the antifouling properties of the membranes. The results showed that taurine and glycidol were successfully introduced onto the membrane surface. The WCA of PP‐T and PP‐G membranes can be reduced to 32° and 26°, and the flux recovery ratio increased around 90.6% and 89.8%, respectively. Based on the experimental results, taurine and glycidol effectively improved the hydrophilic and anti‐fouling performance of PP membrane. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44430.     

Enhanced hydrophilic polysulfone hollow fiber membranes with addition of iron oxide nanoparticles

Membranes are at the heart of hemodialysis treatment functions to remove excess metabolic waste such as urea. However, membranes made up of pure polymers and hydrophilic polymers such as polyvinylpyrrolidone suffer problems of low flux and bio‐incompatibility. Hence, this study aimed to improve polysulfone (PSf ) membrane surface properties by the addition of iron oxide nanoparticles (IONPs ). The membrane surface properties and separation performance of neat PSf membrane and membrane filled with IONPs at a loading of 0.2 wt% were investigated and compared. The membranes were characterized in terms of morphology, pure water permeability (PWP ) and protein rejection using bovine serum albumin (BSA ). A decrease in contact angle value from 66.62° to 46.23° for the PSf /IONPs membrane indicated an increase in surface hydrophilicity that caused positive effects on the PWP and BSA rejection of the membrane. The PWP increased by 40.74% to 57.04 L m^?2 h^?1 bar^?1 when IONPs were incorporated due to the improved interaction with water molecules. Furthermore, the PSf /IONPs membrane rejected 96.43% of BSA as compared to only 91.14% by the neat PSf membrane. Hence, the incorporation of IONPs enhanced the PSf hollow fiber membrane hydrophilicity and consequently improved the separation performance of the membrane for hemodialysis application. © 2017 Society of Chemical Industry     

Preparation and characterization of antifouling and antibacterial polysulfone ultrafiltration membranes incorporated with a silver–polydopamine nanohybrid

A silver–polydopamine (Ag–PDA) nanohybird was used to produce polysulfone (PSf) ultrafiltration membranes with excellent antifouling and antibacterial properties. First, the catechol functional groups of polydopamine (PDA) helped with the in situ immobilization of silver (Ag) nanoparticles (<10 nm) on the PDA sphere surface; this led to the formation of the Ag–PDA nanohybrid. Then, Ag–PDA/PSf hybrid membranes were prepared via the phase‐inversion method, and the influence of Ag–PDA loading on the hybrid membrane properties was systematically investigated. When the content of Ag–PDA was 0.5 wt %, the hybrid membrane achieved optimal separation performance, including a dramatically increased pure water flux and a well‐maintained bovine serum albumin rejection. Furthermore, the Ag–PDA/PSf hybrid membranes presented a significantly enhanced protein‐fouling resistance and a good antibacterial activity. These improvements were attributed to the unique structure and properties of the Ag–PDA nanohybrid because of the synergistic effect of the hydrophilic PDA substrate and well‐distributed Ag nanoparticles. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46430.     

Preparation and modification of nano-porous polyimide (PI) membranes by UV photo-grafting process: Ultrafiltration and nanofiltration performance

Polyimide (PI) membranes were prepared via non-solvent induced phase separation. The prepared PI membranes were modified by ultraviolet light (UV) and graft polymerization of hydrophilic acrylic and amino monomers in the absence and presence of benzophenone (BP) onto the membrane surface to introduce more hydrophilic and lower fouling membranes. Acrylic acid (AA) and 2-hydroxyethylmethacrylate (HEMA) as acrylic monomers, 1,3-phenylenediamine (mPDA) as amino monomer and BP as photo-initiator were used. The unmodified and modified PI membranes were characterized by degree of grafting (DG) and contact angle measurements. They were also characterized by their ultrafiltration performance with pure water and non-skim milk and nanofiltration performance with 500 ppm NaCl and MgSO₄ single solutions. The DG was increased with increasing monomer concentration, especially at presence of BP. The contact angle measurements indicated that hydrophilicity of PI membrane was improved after UV photografting of hydrophilic monomers onto the membrane surface in all cases. The ultrafiltration results showed that the pure water fluxes and milk water permeation of PI membrane declined after monomer photo-grafting while the protein rejection was extremely increased. The decrease in permeability was remarkable in the presence of BP. The mean pore size of base and modified PI membranes ranged from 8.3 to 0.55 nm when calculated from the solute transport data. Moreover, the irreversible flux loss and flux recovery of PI membrane were modified by UV photo-grafting of hydrophilic monomers. All modified membranes showed considerable NaCl and MgSO₄ rejections. In addition, the membrane modified with mPDA at presence of BP showed highest NaCl and MgSO₄ rejections.     

Fabrication of polyamide thin film nanocomposite reverse osmosis membrane incorporated with a novel graphite-based carbon material for desalination

The properties of polyamide (PA) thin film composite (TFC) membranes are affected by many variables, especially the additives in the process of interfacial polymerization that play an important role in the properties of membranes. In this study, a new type graphite carbon was added into organic phase containing trimesoyl chloride for interfacial polymerization with aqueous phase containing m-phenylenediamine to prepare modified polyamide thin film nanocomposite (TFN) membranes for reverse osmosis (RO) adhibition. Polysulfone ultrafiltration membranes were used as the carrier of the interfacial polymerization. The concentration of graphite carbon was selected from 0.002 to 0.01 wt%. The polyamide nanocomposite membrane prepared with the concentration of 0.004 wt% graphite carbon showed the best RO desalination performance, which the water flux of this TFN membrane is over 2.3 times as much as pristine TFC membrane, and the salt rejection is over 99%. This article provides a well-performing polyamide thin film nanocomposite membrane modified by a new-type carbon nanoparticles consequently.     

Fabrication of anti-fouling polyamide nanofiltration membrane by incorporating streptomycin as a novel co-monomer

Polyamide (PA) thin-film composite (TFC) nanofiltration (NF) membrane has extremely broad application prospects in separation of monovalent/divalent inorganic salts mixed solution. However, membrane fouling is the main obstacle to the application of PA, TFC and NF membrane. Streptomycin (SM) is a hydrophilic antibiotic containing a large number of hydroxyl and amino groups. In this work, the NF membrane was prepared via interfacial polymerization (IP) between trimesoyl chloride (TMC) in the organicphaseand SM/piperazine (PIP) mixture in theaqueousphase. The NF membrane structure and performance were characterized in detail. The results showed that SM successfully participated in the IP. The negative charge and hydrophilicity of membrane surface were improved. The prepared membrane exhibited good anti-adhesion and anti-bacterial performance. Additionally, when the SM concentration was 2%, the prepared membrane exhibited the optimal permselectivity. The water permeance was 89.4 L·m^-2·h^-1·MPa^-1. The rejection of NaCl and Na₂SO₄ were 17.17% and 97.84%, respectively. The NaCl/Na₂SO₄ separation factor of the SM2-PIP/TMC membrane in 1000 mg·L^-1 NaCl and 1000 mg·L^-1 Na₂SO₄ mixed solution was 40, which was 3.3 times that of PIP/TMC membrane. It indicated that SM2-PIP/TMC demonstrated excellent monovalent/divalent salts separation performance. This work provided an easy and effective approach to preparing anti-fouling NF membrane while possessing superior monovalent/divalent salts separation performance.     

Comparative impact of SiO2 and TiO2 nanofillers on the performance of thin-film nanocomposite membranes

Nanoparticle (NP) additions can substantially improve the performance of reverse osmosis and nanofiltration polyamide (PA) membranes. However, the relative impacts of leading additives are poorly understood. In this study, we compare the effects of TiO₂ and SiO₂ NPs as nanofillers in PA membranes with respect to permeate flux and the rejection of organic matter (OM) and salts. Thin-film nanocomposite (TFN) PA membranes were fabricated using similarly sized TiO₂ 15 nm and SiO₂ (10 – 20 nm) NPs, introduced at four different NP concentrations (0.01, 0.05, 0.2, and 0.5% w/v). Compared with PA membranes fabricated without NPs, membranes fabricated with nanofillers improved membranes hydrophilicity, membrane porosity, and consequently the permeability. Permeability was increased by 24 and 58% with the addition of TiO₂ and SiO₂ , respectively. Rejection performance and fouling behavior of the membranes were examined with salt (MgSO₄ and NaCl ) and OM (humic acid [HA] and tannic acid [TA]). The addition of TiO₂ and SiO₂ nanofillers to the PA membranes improved the permeability of these membranes and also increased the rejection of MgSO₄ , especially for TiO₂ membranes. The addition of TiO₂ and SiO₂ to the membranes exhibited a higher flux and lower flux decline ratio than the control membrane in OM solution filtration. TFN membranes' HA and TA rejections were at least 77 and 71%, respectively. The surface change properties of NPs appear to play a dominant role in determining their effects as nanofillers in the composite membrane matrix through a balance of changes produced in membrane pore size and membrane hydrophilicity.     

Novel thin-film nanocomposite membrane with water-soluble polyhydroxylated fullerene for the separation of Mg2+/Li+ aqueous solution

Despite the prosperity of membrane technology, the separation efficiency for Mg²⁺/Li⁺ mixture is still far from satisfactory. Herein, a novel thin-film nanocomposite (TFN) membrane was developed by loading polyhydroxylated fullerene (PHF) via interfacial polymerization. The effects of the PHF dosages on the as-developed membranes were investigated comprehensively by XPS, SEM, AFM, contact angle measurements, as well as nanofiltration tests. The results revealed the TFN membrane containing 0.01% (w/v) PHF exhibited the optimum performances. The membrane showed a pure water flux of 6.7 L·m⁻²·h⁻¹·bar⁻¹ and salt rejections with the order of Na₂SO₄ (95.6%) > MgSO₄ (93.6%) > MgCl₂ (89.9%) > NaCl (22.6%) > LiCl (16.3%). The membrane not only presented a separation factor of 13.1 in separating Mg²⁺/Li⁺ mixtures, but also demonstrated excellent antifouling ability, which enables membrane regeneration without operation break, suggesting its great potentials in the recovery of Li⁺ from brine or seawater. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48029.     

负载羧基化球状介孔纳米颗粒TFN膜的研究

在薄层复合膜(thin-film composite membrane, TFC膜)中引入无机纳米颗粒,形成薄层纳米复合膜(thin-film nanocomposite membrane, TFN膜),近几年作为反渗透膜开始应用于水处理研究。但是无机纳米颗粒在TFC膜中的性能的不稳定性和膜的机械强度等变成了突出问题。合成制备了粒径约为110 nm修饰羧基的介孔氧化硅球状纳米颗粒(MSN—COOH),并将其成功地化学键合在TFC膜的表面功能层交联网络中。与TFC膜相比,键合有MSN—COOH的TFN膜,水通量提高了56.2%,保持高脱盐率;由于单分散介孔纳米颗粒表面亲水官能团的引入,使膜表面的亲水性有很大程度提高,单分散介孔纳米颗粒在基体中的有序排列,使膜表面粗糙度降低,提高了膜的抗污染能力。与普通TFN膜相比较,具有更好的稳定性和柔韧性,可以在长时间高压过滤操作下保持稳定。     

金属有机骨架/聚酰胺薄层纳米复合膜的研究进展

相较于传统聚酰胺薄层复合（TFC）膜,金属有机骨架/聚酰胺薄层纳米复合（TFN）膜得益于MOFs材料的高比表面积、有序可控的孔隙结构、良好的聚合物相容性和可定制的化学功能,展现出更高的渗透选择性,在工业应用中显示出巨大的分子和离子分离潜力。本文首先简述了MOFs聚酰胺复合膜的研究背景,然后从MOFs材料的特性和MOFs聚酰胺复合膜的制备策略两个方面出发,总结了MOFs聚酰胺膜研究的最新进展。讨论了MOFs的物化特征在TFN膜的微观结构和分离性能中起的作用;介绍了MOFs聚酰胺复合膜的制备策略,重点对MOFs负载方法及效率进行了分析。最后简述了MOFs聚酰胺复合膜在气、液体系分离中的应用;对MOFs聚酰胺膜在应用过程中的稳定性问题进行了分析,并对未来MOFs聚酰胺复合膜优化MOFs负载和功能性设计的研究进行了展望。     

Sub-20 nm Bilayer Hydrophilic Poly(Vinyl Pyrrolidone) Coatings for Antifouling Nanofiltration Membranes

Fouling is a major concern in membrane technology. Neutral hydrophilic coatings alleviate fouling on membrane surfaces by passively resisting the adsorption of foulants without altering the properties of membranes. Coatings, however, often result in a trade-off of reduced water flux. Ultrathin hydrophilic coatings could minimize the influence on water flux, but its fabrication is challenging via traditional methods. Here, fabrication of sub-20 nm bilayer hydrophilic coating is reported that is grafted onto nanofiltration (NF) membranes via a one-step initiated chemical vapor deposition (iCVD) method. The iCVD coating is conducted by conformally depositing a crosslinked poly(vinyl pyrrolidone-co-ethylene glycol dimethacrylate) bottom layer on pretreated NF membrane, followed by in situ grafting of poly(vinyl pyrrolidone) homopolymer to further improve surface hydrophilicity. Both thickness and crosslinking degree of the bottom coating are systematically tailored to reduce its side effects on permeation rate and salt rejection. The modified NF membranes exhibit 99% lower microbial adhesion compared to the pristine membrane, with minor impact on permeation and salt rejection performance. The coating is also stable against continuous ultrasonication. The reported method is thus expected to shed light on facile novel ways of reducing membrane fouling in desalination and industrial wastewater treatment.     

Forward osmosis water desalination: Fabrication of graphene oxide-polyamide/polysulfone thin-film nanocomposite membrane with high water flux and low reverse salt diffusion

This paper investigates the synthesis of graphene oxide (GO)-incorporated polyamide thin-film nanocomposite (TFN) membranes on polysulfone substrate for forward osmosis applications. The GO nanosheets were embedded into polyamide layer using different concentrations (0.05?0.2 wt%). The results represented the alteration of polyamide surface by GO nanosheets and enhancing the surface hydrophilicity by increasing the GO loading. The results showed that the water flux for 0.1 wt% GO embedded nanocomposite (TFN) membrane was 34.7 L/m² h, representing 90% improvement compared to the thin-film composite, while the salt reverse diffusion was reduced up to 39%.     

Fabrication of innovative forward osmosis membranes via multilayered interfacial polymerization on electrospun nanofibers

Practical application of forward osmosis (FO) membranes is beset by low water flux and vulnerability of selective polyamide (PA) layers. Herein, novel composite membranes were fabricated with multilayered PA via cyclic interfacial polymerization (IP) on electrospun polyethersulfone (PES) nanofiber substrates to realize high performance FO. The membrane fabrication conditions were optimized detailedly with respect to the morphologies, physicochemical properties, and FO performances. It is indicated that the PES concentration has great impacts on the morphology, thickness, and fiber diameter of the electrospun substrates and the optimal concentration is proved to be 26 wt %. After multilayered IP, the membrane thickness, surface hydrophilicity, and mechanical strength increased with IP cycles. The optimized FO membranes with two PA layers show much higher water flux and membrane selectivity compared with the commercial thin film composite membranes, holding great promise for water purification and seawater desalination. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47247.     

Fabrication and performance of a polyethersulfone nanofiltration membrane impregnated with a mesoporous silica–poly(1‐VInylpyrrolidone) nanocomposite

Fouling is a serious problem in the membrane formation process. Adding hydrophilic polymers or inorganic particles into the membrane is an effective way for improving the antifouling performance. However, most of the water‐soluble polymeric additives leach out during the phase inversion process, and the inorganic particles are prone to agglomerate in the membrane, which decreases the antifouling property of the membrane. In this study, poly(1‐vinylpyrrolidone) (PVP) was grafted onto mesoporous silica (MS) nanoparticle surface, and polyethersulfone (PES)/MS–PVP nanocomposite membranes were fabricated by the phase inversion method. MS–PVP dispersed well on the membrane surface, and the hydrophilicity of the PES/MS–PVP membranes increased with increasing content of MS–PVP. PES/MS–PVP membranes exhibited higher water flux than that of the bare PES membrane without any loss in NaCl rejection, and water flux of 25 L/m²h could be achieved by the membrane containing 3% of MS–PVP, which is almost 1.5 times as high as that of bare PES membrane at 0.6 MPa. The protein adsorption onto the membrane surface declined significantly from 49 to 25 mg/cm² when the MS–PVP loading increased from 0% to 3%. POLYM. COMPOS., 38:908–917, 2017. © 2015 Society of Plastics Engineers