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Fabricating composite membranes with enhanced permeance and desirable properties for treating aqueous solutions is an effective approach to developing advancing membrane technology. In this study, a sensor membrane was prepared for the sorption and detection of As(III) ions in aqueous solutions. A novel membrane based on polysulfone (PSF) with varying concentrations of iron complexes was prepared using the phase inversion method. The composite membranes were analyzed using FTIR, SEM, XRD, AFM, and TGA. The structures of the membranes exhibited good dispersibility and compatibility with the complexes within the PSF matrix. TGA analysis showed that the thermal stability of the membranes was significantly improved compared to that of pure PSF. The membranes were evaluated as sensors for detecting extremely low concentrations of As(III) ions in aqueous solutions using the quartz crystal microbalance technique. The results indicate that the composite membrane sensors could detect small amounts of As(III) ions in aqueous solutions at different temperatures. Notably, PSF/TBPFe5 at 45°C demonstrated superior sensitivity for As ion detection. Therefore, these membranes are ideal materials for assessing water quality. [ABSTRACT FROM AUTHOR]

Polysulfone (Psf) ultrafiltration flat-sheet membranes were modified with hydroxyapatite (HA) powder during preparation using the wet-phase inversion method. HA was incorporated to enhance the protein separation capabilities. The asymmetric Psf membranes were synthesized using NMP as the solvent. Through Scanning Electron Microscopy (SEM) analysis, it was revealed that HA was distributed across the membrane. Incorporating HA led to higher flux, the improved rejection of protein, and enhanced surface hydrophilicity. The permeability flux increased with HA concentration, peaking at 0.3 wt.%, resulting in a 38% improvement to 65 LMH/bar. Whey protein separation was evaluated using the model proteins BSA and lysozyme, representing α-Lactalbumin. The results of protein rejection for the blend membranes indicated that the rejection rates for BSA and lysozyme increased to 97.2% and 73%, respectively. Both the native and blend membranes showed similar BSA rejection rates; however, the blend membranes demonstrated better performance in lysozyme separation, indicating superior selectivity compared to native membranes. The modified membranes exhibited improved hydrophilicity, with water contact angles decreasing from 66° to 53°, alongside improved antifouling properties, indicated by a lower flux decline ratio value. This simple and economical modification method enhances permeability without sacrificing separation efficiency, hence facilitating the scalability of membrane production in the whey protein separation industry. [ABSTRACT FROM AUTHOR]

As a promising wastewater treatment technology, ultrafiltration membranes face challenges related to fouling and flux reduction. To enhance these membranes, various strategies have been explored. Among them, the incorporation of nano-activated carbon (nAC) powder has emerged as an effective method. In this study, composite polysulfone (PSF) ultrafiltration membranes were fabricated using nAC powder at concentrations ranging from 0 to 8 wt.%. These membranes underwent comprehensive investigation, including assessments of membrane morphology, hydrophilicity, pure water flux, equilibrium water content, porosity, average pore size, and protein separation. The addition of activated carbon improved several desirable properties. Specifically, the hydrophilicity of the PSF membranes was enhanced, with the contact angle reduced from 69° to 58° for 8 wt.% of nAC composite membranes compared to the pristine PSF membrane. Furthermore, the water flux test revealed that 6 wt.% activated carbon-based membranes exhibited the highest flux, with a nearly 3 times improvement at 2 bar. Importantly, this enhancement did not compromise the protein rejection. Additionally, the introduction of nAC had a significant effect on the membrane's pore size by improving lysozyme rejection up to 40%. Overall, these findings will guide the selection of the optimal concentration of nAC for PSF ultrafiltration membranes. [ABSTRACT FROM AUTHOR]

This paper is devoted to estimating the effect of coloring (RAL 7037) polycarbonate and polysulfone with different yellowness indices on a complex of optical, physicomechanical, and rheological properties. It is shown that the introduction of color additives into heat-resistant polymers does not radically change their principal rheological and physicomechanical properties and does not require any modification for the methods and conditions of their processing. [ABSTRACT FROM AUTHOR]

In a previous study, we demonstrated a change in membrane morphology and gas separation performance by varying the recipe of a casting solution based on polysulfone in a certain solvent system. Although all results were reproducible, all used solvents were harmful and not sustainable. In this study, the solvents tetrahydrofuran (THF) and N,N-dimethylacetamide (DMAc) are replaced by the more sustainable solvents 2-methyl-tetrahydrofuran (2M-THF), N-butyl pyrrolidinone (NBP) and cyclopentyl methyl ether (CPME). The gas permeation performance and, for the first time, morphology of the membranes before and after solvent replacement were determined and compared by single gas permeation measurements and SEM microscopy. It is shown that THF can be replaced by 2M-THF and NBP without decreasing the gas permeation performance. With CPME replacing THF, no membranes were formed. Systems with 2M-THF as a THF alternative showed the best gas permeation results. Permeances for the tested gases oxygen (O2), nitrogen (N2), carbon dioxide (CO2) and methane (CH4) were 5.91 × 10−2, 8.84 × 10−3, 4.00 × 10−1 and 1.00 × 10−2 GPU, respectively. Permselectivities of those membranes for the gas pairs O2/N2, CO2/N2 and CO2/CH4 were 6.7, 38.3 and 34.0, respectively. When also replacing DMAc in the solvent system, no or only porous membranes were obtained, even if the precipitation procedure was adjusted. These findings indicate that a complete replacement of the solvent system without affecting the membrane morphology or gas permeation performance is not possible. By varying the temperature of the precipitation bath, the formation of mechanically stable PSU membranes is possible only if THF is replaced by 2M-THF. [ABSTRACT FROM AUTHOR]

Membranes have been prepared from polysulfone and graphene oxide with mass concentrations from 0 to 0.4%. A series of experiments were conducted to study the permeability of the obtained samples at pressures of 10, 15, and 20 atm. The experimental time dependences of the permeated water volume at a constant pressure were obtained. The dependence of the membrane permeability on the graphene oxide concentration and pressure was calculated. Conclusions were drawn about the influence of graphene oxide concentration and pressure on the permeability of the samples. [ABSTRACT FROM AUTHOR]

This study aimed to synthesize graphene oxide (GO) nanoparticles and subsequently modify them with trimethylsilyl chloride (TMSCl). The modified GO was employed in the fabrication of a polysulfone-graphene oxide (PSf-GO) ultrafiltration mixed-matrix membrane for oil and water separation. PSf-GO ultrafiltration mixed-matrix membranes were fabricated using different amounts of modified GO. The structure, properties, and characteristics of the synthesized GO and fabricated membranes were studied using various techniques, including contact angle measurements, atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The performance of the membranes in the separation of oil and water and their antifouling affinities were evaluated and compared. Contact angle measurements indicated that the addition of GO nanoparticles increased the hydrophilicity of the membranes. The UF-0.50 (0.50%Wt GO@TMSCl) membrane demonstrated a water flux of 113.35 L/m2 h and oil rejection of 97.44% during the ultrafiltration process, representing the highest performance among the fabricated membranes. Membrane fouling analysis revealed that this membrane performed better than the others, which could be attributed to the proper and uniform nanoparticle loading. The most favorable UF membrane antifouling performance was observed for the UF-0.5 membrane with a flux recovery percentage of 96.30%. Because of the efficient and appropriate performance of the UF-0.5 membrane, it was revealed that this membrane can be used as an effective UF membrane for the oil-water separation process, as well as in further studies. [ABSTRACT FROM AUTHOR]

In a previous study, we demonstrated a change in membrane morphology and gas separation performance by varying the recipe of a casting solution based on polysulfone in a certain solvent system. Although all results were reproducible, all used solvents were harmful and not sustainable. In this study, the solvents tetrahydrofuran (THF) and N,N-dimethylacetamide (DMAc) are replaced by the more sustainable solvents 2-methyl-tetrahydrofuran (2M-THF), N-butyl pyrrolidinone (NBP) and cyclopentyl methyl ether (CPME). The gas permeation performance and, for the first time, morphology of the membranes before and after solvent replacement were determined and compared by single gas permeation measurements and SEM microscopy. It is shown that THF can be replaced by 2M-THF and NBP without decreasing the gas permeation performance. With CPME replacing THF, no membranes were formed. Systems with 2M-THF as a THF alternative showed the best gas permeation results. Permeances for the tested gases oxygen (O2), nitrogen (N2), carbon dioxide (CO2) and methane (CH4) were 5.91 × 10−2, 8.84 × 10−3, 4.00 × 10−1 and 1.00 × 10−2 GPU, respectively. Permselectivities of those membranes for the gas pairs O2/N2, CO2/N2 and CO2/CH4 were 6.7, 38.3 and 34.0, respectively. When also replacing DMAc in the solvent system, no or only porous membranes were obtained, even if the precipitation procedure was adjusted. These findings indicate that a complete replacement of the solvent system without affecting the membrane morphology or gas permeation performance is not possible. By varying the temperature of the precipitation bath, the formation of mechanically stable PSU membranes is possible only if THF is replaced by 2M-THF.

AbstractThe majority of treatments are performed with polysulfone (PSf) membranes. The main issue of the PSf membrane is its lack of endothelial function, leading to various processes like platelet adhesion, protein adsorption, and thrombus formation when comes in contact with blood. The crucial aspect in the development of hemodialysis (HD) membrane materials is a biocompatibility factor. This study aims to improve the performance and biocompatibility of PSf membranes by utilizing polyethylene glycol (PEG) as a pore-forming agent and polyacrylamide (PAA) as a multifunctional modifying additive owing to its non-toxic, and biocompatible nature. The formulated HD membranes were characterized using Fourier Transform Infrared (FTIR) spectroscopy, Scanning Electron Microscopy (SEM), and Water Contact Angle (WCA) measurements. The biocompatibility results showed that PSf-PAA membranes reduced the adsorption of bovine serum albumin (BSA) protein, hemolysis process, thrombus formation, and platelets adhesion with improved in vitro cytotoxicity results as well as anticoagulation performance. The protein separation results showed that PSf-PAA membranes were able to reject 90.1% and 92.8% of BSA protein. The membranes also showed better uremic waste clearance for urea (76.56% and 78.24%) and creatinine (73.71% and 79.13%) solutes, respectively. It is conceivable that these modern-age membranes may surpass conventional HD membranes regarding both efficiency and effectiveness. [ABSTRACT FROM AUTHOR]

This study investigated the effect of low-concentration fumed silica (FS) in polyethersulfone (PES) membranes. The PES/FS blend membrane was fabricated using a wet phase inversion technique as a flat sheet membrane. Scanning electron microscopy analysis revealed improved pore connectivity and rounder middle structures due to the addition of fumed silica. The experimental results indicated that the fabricated membranes fell within the ultrafiltration range, with pure water flux increasing as fumed silica concentration rose. The pure water flux improved by 64% compared to the native PES membrane. Furthermore, the blend membranes exhibited better selectivity, rejecting pepsin and lysozyme 11% and 19% more efficiently, respectively. Although the low concentration of fumed silica had minimal impact on the water contact angles of the membrane surface, all membranes demonstrated hydrophilicity. This cost-effective approach enhances permeability while maintaining separation characteristics, making it suitable for clean water applications. [ABSTRACT FROM AUTHOR]

Background: The use of Polysulfone (PSf) as membrane material for dialysis therapy is becoming more common. However, the PSf membrane can cause the adsorption of blood proteins followed by the adhesion of platelets, destruction of red blood cells, and thrombus formation. One of the biggest challenges in creating membranes for hemodialysis (HD) applications is ensuring biocompatibility. Therefore, to maintain the biocompatibility of PSf membranes, further modifications are necessary. Methods: In this study, the performance and biocompatibility of PSf membranes were improved by the impregnation of TiO2‐hydroxyapatite composite as an additive. The TiO2‐hydroxyapatite composite was first synthesized via sintering at 1200°C, and then a dope solution composed of pristine PSf polymer solution in N‐Methyl‐2‐pyrrolidone solvent (NMP) and different wt% ratios of the synthesized composite were prepared, and resultant membranes were fabricated using a film applicator via a phase inversion scheme using water as a non‐solvent exchange medium. The synthesized composite was characterized using SEM, EDX, and XRD techniques. Results: The FTIR analysis confirmed the weak interaction of PSf polymer with the hydroxyapatite moiety of the composite. The interaction of the synthesized composite within the membrane matrix was evaluated via leaching ratio results. The hydrophilicity, pore profile, and pure water permeation flux rates were also determined. The results of the biocompatibility study showed that membranes based on TiO2‐hydroxyapatite composite had reduced adsorption of BSA protein by 34.41% as well as less than 5% hemolysis ratio. Additionally, the study displayed thrombus formation ranging from 2.08% to 8.69%, respectively. The dialysis results indicated that compared with the original PSf membrane, the TiO2‐hydroxyapatite composite showed high clearance rates for urea (73.81%) and creatinine (72.13%) solutes, respectively. Conclusion: Therefore, blending TiO2‐hydroxyapatite composite in the PSf membrane significantly improved the biocompatibility and removal ability of uremic solutes. [ABSTRACT FROM AUTHOR]

Separation of heavy metals to obtain potable water for domestic and agricultural applications is important considering health effects, bioaccumulation properties and applicability. The separation of Cr and Mn salts by Donnan exclusion are investigated using polysulfone (PSF) based membranes modified by anchoring ZnO nanoparticles. Use of Acid-treated ZnO nanoparticle enhnanced rejection properties for Cr and Mn (97.12 and 98.37%, respectively) for membranes based on 40% PSF, 8% PEG -400 and 0.8% ZnO. The use of polyethylene glycol (PEG)with molecular weight of 200 Da enhanced rejection properties to ~ 99%. This would provide excellent pathway for PSF membrane modification without affecting stability.Separation was dependent uponconcentrations of PSF, PEG, ZnO nanoparticles in dope solution, and bubble point pressure, pore size, number of pores, etc. Analysis of these properties and effect would provide pathway for design of membranes for heavy metal removal and process applications. Hence, they were analyzed using R studio multi-attribute linear regression model. Membrane performance regression analysis provided correlation with 95% fitting accuracy with 0.98 coefficient of regression, suggesting good relationship between predicted and observed data. This shows the applicability of model to save time and cost involved in designing membrane formation parameters and properties with optimized applicability [ABSTRACT FROM AUTHOR]

Decreasing groundwater levels, increasing world population, and pollution of water resources by industries lead to the use of new technologies for augmenting the fresh water supply such as its desalination. Chitosan-modified zinc oxide (C-ZnO) nanoparticles were synthesized and used for surface modification of polysulfone (PSf) in water desalination. PSf /C-ZnO membrane was fabricated through the phase inversion method and characterized by Fourier transfer infrared (FTIR), X-Ray diffraction (XRD), field emission scanning electron microscope (FESEM), atomic force microscope (AFM), energy dispersive X-ray (EDX), Braunauer-Emmett-Teller (BET), and contact angle. The nanoparticle effect on the membrane properties was investigated by measuring the pure water flux and solute rejection under two constant pressures, at 6 and 10 bar, and the salts concentration of MgSO4, MgCl2, NaCl, and CaCl2 at 1 gL−1. The results showed that nanoparticles increased the hydrophilicity of the pristine PSf membrane while slightly decreasing the water permeability. Moreover, the salt rejection increased with the nanoparticle addition up to 0.2 wt.% while it decreased with 0.5 wt.% nanoparticle due to changing the membrane finger-like pores sublayer structure. [ABSTRACT FROM AUTHOR]

Forward osmosis (FO) has emerged as a highly promising and energy‐efficient technology for seawater desalination. This study investigates the enhancement of polyethersulfone/polysulfone FO membranes by incorporating graphene oxide (GO) for seawater desalination. The effects of different GO concentrations on membrane properties and FO desalination performance were examined. Among the tested membranes, the one with 0.04 wt% GO exhibited optimal hydrophilicity, as indicated by a lower contact angle (53.93° ± 5.61°), higher porosity (69.86 ± 0.66), and a minimal structure parameter (312.33 μm). The GO.04 membrane demonstrated significantly improved water flux (Jw) of 106 L/m2 h and low reverse salt flux (Js) of 0.69 g/m2 h. Compared to the GO0 membrane without GO, the water flux was 103% higher without compromising salt selectivity (Js/Jw = 0.0065 g/L) when using distilled water as the feed solution (FS) and 1 M NaCl as the draw solution. However, over a threshold of 0.09%, GO concentration on membrane surfaces and pores can impede water flow, reducing porosity and increasing resistance to membrane transport. The GO.04 membranes also exhibited high water flux (113, 94.28, and 84.64 L/m2 h) when brackish water with different NaCl concentrations (5000, 10,000, and 15,000 mg/L) was used as the FS. Moreover, under real seawater conditions from the Suez Canal, the GO.04 FO membrane showed a significantly higher water flux of 94.3 L/m2 h. These findings provide valuable insights into the desalination of actual seawater from the Suez Canal, offering significant potential for the advancement of water treatment and resource management practices. [ABSTRACT FROM AUTHOR]

Textile industry wastewater is rich in color, has a low BOD/COD ratio, and contains high levels of salts (TSS and TDS). There is the presence of heavy metals at high concentrations. This has a major environmental impact underlined by chemical oxygen demand (COD) and biochemical oxygen demand (BOD). These issues arise from the presence of dye, pieces of fiber, and other surface treatment agents viz., detergents, salts, and caustic soda. Hence membrane optimization is investigated for treatment and recovery of these components, which would provide both economic and ecological benefits. It was required to provide chemically stable membranes, which would provide efficient separation for these components at effluent conditions of pH, temperature, and other parameters. A major challenge here was a selection of membrane and backing material with sustainability at low pH conditions of textile effluent. Hencepolysulfone (PSF) based membranes with cellulose as backing were optimized and tried for clarification of textile effluent. These membrane properties were further optimized for the recovery of other components. Membrane formation and performance were optimized with the proposition of a two-stage process for clarification and further concentration. Formed membranes showed excellent removal of impurities, validated by ICPMS. The clarified solution can be further treated for concentration enhancement from 7 to 20 %. Such recovered alkaline solution can be recycled or used in further applications. This solution provides an economically attractive and environmentally benign process. Further, it provides the advantages of low energy consumption, high efficiency in separation, and non-thermal processing of sensitive composite products. [ABSTRACT FROM AUTHOR]

This study that modified polysulfone membranes with different end-group chemical functionalities were prepared using chemical synthesis methods and experimentally characterized. The molecular dynamics (MD) method were used to discuss the adsorption mechanism of proteins on functionalized modified polysulfone membrane materials from a molecular perspective, revealing the interactions between different functionalized membrane surfaces and protein adsorption. Theoretical analysis combined with basic experiments and MD simulations were used to explore the orientation and spatial conformational changes of protein adsorption at the molecular level. The results show that BSA exhibits different variability and adsorption characteristics on membranes with different functional group modifications. On hydrophobic membrane surfaces, BSA shows the least stable configuration stability, making it prone to nonspecific structural changes. In addition, surface charge effects lead to electrostatic repulsion for BSA and reduce the protein adsorption sites. These MD simulation results are consistent with experimental findings, providing new design ideas and support for modifying blood-compatible membrane materials. [ABSTRACT FROM AUTHOR]

The most prevalent type of hemodialysis membrane is polysulfone (PSf). However, due to inadequate biocompatibility, it significantly compromises the safety of dialysis for patients. In this study, we modify the surface of the PSf membrane with 2,4-dihydroxybenzophenone (DBPh) groups to serve as anchoring sites during UV irradiation. Subsequently, a tailored sulfonated dihydroxy propyl chitosan (SDHPCS) is grafted onto the modified PSf membrane to compensate for the deficiencies in hydrophilic additives. The modified PSf membrane exhibits outstanding hydrophilicity and stability, as demonstrated by its characterization and evaluation. This paper focuses on investigating the interaction between platelet membrane formation, protein adsorption, and anticoagulant activity. The results show that the modified PSf membrane exhibits remarkable enhancement in surface hydrophilicity, leading to a significant reduction in protein and platelet adsorption as well as adhesion. [ABSTRACT FROM AUTHOR]

This study explores the utilization of electrospun polysulfone (PSF) as a thin-film support in the pressure-retarded osmosis (PRO) system, leveraging its notable thermal, chemical, and oxidative stability. To enhance the efficiency of the PRO system, the inherently hydrophobic PSF surface is modified through functionalization with benzenesulfonamide groups (BSA-PSF). The modification process involves chloromethylation of PSF, followed by substitution with BSA, and subsequent electrospinning to produce BSA-PSF fibers. A thin-film composite forward osmosis membrane, composed of an electrospun BSA-PSF support layer and a polyamide thin layer synthesized through interfacial polymerization (BSA-PSF/PA), is developed. The incorporation of BSA improves the hydrophilicity of the membrane surface, while also imparting antibacterial features to the electrospun BSA-PSF. Comparative analyses with pristine PSF membranes reveal that the pure water flux of the BSA-PSF membrane achieves a notable 65 LMH, surpassing the pristine PSF membrane’s flux of 45 LMH. Moreover, protein absorption is significantly reduced in the BSA-PSF membrane (40.6 μg cm−2) compared to the unmodified PSF membrane (64.2 μg cm−2). The establishment of a hydration layer near the surface, facilitated by hydrogen interactions between water units and the hydrophilic sulfonamide chains in the polymer, contributes to lower protein adsorption than observed in the pristine PSF membrane. Notably, the prepared BSA-PSF/PA membrane exhibits advanced surface hydrophilicity, commendable antibacterial properties, exceptional fouling resistance, and high water permeability. These attributes position it as a promising candidate for widespread applications in power generation and large-scale water treatment. BSA functionalized the electrospun PSF used as the PRO membrane’s thin-film support. The introduction of BSA to PSF improved the hydrophilicity, water flux, antibacterial properties, and fouling resistance of thin-film composite PRO membraneArticle Highlights: BSA functionalized the electrospun PSF used as the PRO membrane's thin-film support. The introduction of BSA to PSF improved the membrane's hydrophilicity and water flux. BSA-PSF nanofibers exhibit antibacterial properties. BSA-PSF/PA membrane has satisfactory fouling resistance [ABSTRACT FROM AUTHOR]

In this study, membranes blended with polysulfone (PSU) and polyetherimide (PEI) polymers in different ratios were fabricated. Their potential to remove pollutants from rivers, which are a potential drinking water source, was investigated. Scanning electron microscopy analysis revealed that the PSU membranes had a dense and homogeneous layer, whereas the addition of PEI formed a spongy substrate. The water content of the fabricated membranes varied between 5.37 and 22.42%, porosities 28.73–89.36%, contact angles 69.18–85.81%, and average pure water fluxes 257.25–375.32 L/m2 h. The blended membranes removed turbidity, chloride, alkalinity, conductivity, sulfate, iron, manganese, and total organic carbon up to 98.32, 92.28, 96.87, 90.67, 99.58, 94.63, 97.48, and 79.11%, respectively. These results show that when PEI was added to the PSU polymer, the filtration efficiency increased owing to an increase in the hydrophilicity of the membranes. Blending these two polymers enabled the optimization of membrane properties such as permeability, selectivity, and mechanical strength. In addition, membrane fabrication processes are simple and incur low costs. HIGHLIGHTS The addition of polyetherimide (PEI) significantly increased the water content and porosity of the polysulfone membranes.; The pure water fluxes of the membranes increased directly to the PEI ratio.; All membranes removed more than 90% turbidity, chloride, alkalinity, conductivity, sulfate, iron, and manganese.; The total organic carbon removal efficiency increased as the PEI ratio increased.;

Abstract Drinking water contaminated by pathogenic micro-organisms increases the risk of infectious gastrointestinal disease which could potentially lead to acute kidney injury and even death, particularly amongst the young and the elderly. Earlier studies have shown a substantial reduction in the incidence of diarrheal disease over a period of one year using a polysulfone membrane water gravity-powered water filtration device. The current report is a continuation of these studies to assess the long-term effects of the innovative method on diarrheal incidence rates over a 4-year follow-up period. This follow-up study monitored the trend of self-reported diarrheal events in all households in the previously studied villages for 5 months, in the last half of each study year, using the same questionnaire utilized in the earlier study. Three villages that had no device yet installed served as controls. We computed monthly diarrheal incidence rates for all study years (standardized to per 100 person-months) and compared these to the pre-device incidence rate in 2018 and in the control group, using the Wilcoxon rank sum exact test. The average diarrheal incidence rates of 1.5 p100pm in 2019, 2.19 p100pm in 2021, and 0.54p100pm in 2022 were significantly different from an earlier study that reported 17.8 p100pm rates before the devices were installed in 2018, (all p-values

In this study, Zeolitic Imidazolate Framework-8 (ZIF-8) and modified ZIF-8 (ZIF-8@PEI)with polyethyleneimine (PEI) were used as dispersed particles inside the polysulfone (PSF) matrix to separate CO2 and CH4. The distributions of dispersed particles in mixed matrix membranes (MMMs) were analysed with the help of Fourier transfer infrared radiation, Thermal gravimetric analysis, Scanning electronic microscope and X-ray diffraction. The mixed matrix membranes investigated the permeability and selectivity of pure gas (CO2) and mixed gas (CO2/CH4). It was highest at 5 wt% ZIF-8@PEI blended into the PSF matrix. In case of pure gas studies, we investigated the CO2 permeability (18.10 Barrer) and CO2/CH4 selectivity (23.91) as compared to ZIF-8/PSF MMM (10.36 Barrer, 5.81); and in case of mixed gas studies, the CO2 permeability (17.11 Barrer) and CO2/CH4selectivity (21.28) as compared to ZIF-8/PSF MMM (7.86 Barrer, 4.21).Using DFT studies, the interaction energies of the ZIF-8@PEI material with CO2 and CH4 gas molecules werefound to be -74.39 kJ/mol and -23.25 kJ/mol, respectively. It was more toward the ZIF-8@PEI-CO2geometry complex.From the observation, the experimentalgas permeation results and DFT studiesinvestigated that ZIF-8@PEI filler can be a good candidate for applying CO2 capture.

Increasing demands for clean energy and more efficient separation techniques have spurred the fabrication and development of advanced membrane materials for gas separation applications. Methane (CH4), carbon dioxide (CO2), hydrogen sulfide (H2S), and higher hydrocarbons are the most important constituents of natural gas, which induces global warming and lowers the calorific value of fossil fuels. Membrane technology has been proven to be one of the most promising and advanced technologies for CO2 capture and separation. In this study, blended membranes composed of different weight percents of polysulfone and cellulose triacetate were fabricated and evaluated for their CO2/CH4 separation performance. Polysulfone and cellulose triacetate were both selected because they are chemically compatible, have good mechanical strength, are economical, have better separation performance, and are green in nature as well. The fabrication process involves the preparation of cellulose triacetate/polysulfone well-homogenized blended membrane solutions in N-methyl pyrrolidone, followed by the solution casting technique. The fabricated membranes were then characterized using various techniques. Dense, defect-free membranes exhibit promising performance in terms of CO2/CH4 selectivity, showing a significant improvement over the pristine membranes without compromising on the permeabilities. On Robeson's upper bound graph, a notable CO2/CH4 selectivity of 30.70 with a CO2 permeability of 11.12 Barrer was observed for a 6 weight percent cellulose triacetate/polysulfone sample at 4 bars, as compared to the selectivity of pristine cellulose triacetate and polysulfone, which had a value of 9.82 and 10.35, respectively. Moreover, the ultimate tensile strength test results show an improvement in tensile strength of up to 62% for the 6 weight percent sample as compared to the pure cellulose triacetate membrane. [ABSTRACT FROM AUTHOR]

Composites based on polysulfone materials filled with various types of graphite and carbon black were studied and a solution technique was used to create composite materials with filling degrees ranging from 30 to 70% by weight. High filling levels with graphite fillers enabled thermal conductivity of 17.4 W/m·K to be achieved. The addition of carbon black as a filler to the composite helped to improve its mechanical characteristics, and its influence on electrical and thermal conductivity has also been explored. Natural graphite provides the best effect on composite thermal and electrical properties, whereas using artificial graphite allows to improve the mechanical behavior of composites. The relationship between sample density, porosity, and composition, as well as the effect of these factors on composite conductivity, has been studied and addressed. [ABSTRACT FROM AUTHOR]

Blood oxygenators are used to saturate oxygen levels and remove carbon dioxide from the body during cardiopulmonary bypass. Although the natural lung is hydrophilic, commercially used oxygenator materials are hydrophobic. Surface hydrophobicity weakens blood compatibility, as long‐term contact with the blood environment may lead to different degrees of blood activity. Polysulfone may be considered an alternative hydrophilic material in the design of oxygenators. Therefore, it may be directed toward developing hydrophilic membranes. This study aims to investigate the feasibility of achieving blood gas transfer with a polysulfone‐based microporous hollow fiber membrane and compare it with the commercially available polypropylene membranes. Structural differences in the membrane morphology, surface hydrophilicity, tortuosity, mass transfer rate, and material properties under different operation conditions of temperature and flow rates are reported. The polysulfone membrane has a water contact angle of 81.3°, whereas a commercial polypropylene membrane is 94.5°. The mass transfer resistances (s/m) for the polysulfone and polypropylene membranes are calculated to be 4.8 × 104 and 1.5 × 104 at 25°C, respectively. The module made of polysulfone was placed in the cardiopulmonary bypass circuit in parallel with the commercial oxygenator, and pH, pO2, pCO2 levels, and metabolic activity were measured in blood samples. [ABSTRACT FROM AUTHOR]

The chemical structure of the surface of glass fibers, including silanized fibers, was studied. Highly efficient heat-resistant composites were obtained by impregnating silanized glass fiber with a polysulfone solution, and the effect of modification of the surface of glass fibers on the physical, mechanical and thermophysical properties of the composite materials was studied. As a result of the study, it was found that the fiber-to-polymer ratio of 70/30 wt.% showed the best mechanical properties for composites reinforced with pre-heat-treated and silanized glass fibers. It has been established that the chemical treatment of the glass fibers with silanes makes it possible to increase the mechanical properties by 1.5 times compared to composites reinforced with initial fibers. It was found that the use of silane coupling agents made it possible to increase the thermal stability of the composites. Mechanisms that improve the interfacial interaction between the glass fibers and the polymer matrix have been identified. It has been shown that an increase in adhesion occurs both due to the uniform distribution of the polymer on the surface of the glass fibers and due to the improved wettability of the fibers by the polymer. An interpenetrating network was formed in the interfacial region, providing a chemical bond between the functional groups on the surface of the glass fiber and the polymer matrix, which was formed as a result of treating the glass fiber surface with silanes, It has been shown that when treated with aminopropyltriethoxysilane, significant functional unprotonated amino groups NH+/NH2+ are formed on the surface of the fibers; such free amino groups, oriented in the direction from the fiber surface, form strong bonds with the matrix polymer. Based on experimental data, the chemical structure of the polymer/glass fiber interface was identified. [ABSTRACT FROM AUTHOR]

Drinking water contaminated by pathogenic micro-organisms increases the risk of infectious gastrointestinal disease which could potentially lead to acute kidney injury and even death, particularly amongst the young and the elderly. Earlier studies have shown a substantial reduction in the incidence of diarrheal disease over a period of one year using a polysulfone membrane water gravity-powered water filtration device. The current report is a continuation of these studies to assess the long-term effects of the innovative method on diarrheal incidence rates over a 4-year follow-up period. This follow-up study monitored the trend of self-reported diarrheal events in all households in the previously studied villages for 5 months, in the last half of each study year, using the same questionnaire utilized in the earlier study. Three villages that had no device yet installed served as controls. We computed monthly diarrheal incidence rates for all study years (standardized to per 100 person-months) and compared these to the pre-device incidence rate in 2018 and in the control group, using the Wilcoxon rank sum exact test. The average diarrheal incidence rates of 1.5 p100pm in 2019, 2.19 p100pm in 2021, and 0.54p100pm in 2022 were significantly different from an earlier study that reported 17.8 p100pm rates before the devices were installed in 2018, (all p-values < 0.05). Concomitantly, self-reported diarrheal infections were substantially higher in the “control villages” not yet having the filtration device installed (80.9, 77.6, and 21.5 per 100 pm). The consistent and large reduction in diarrhea incidence documents the long-term efficacy of the use of the membrane filtration device. This simple water purification method using gravity flow improves public health in remote regions with limited resources. [ABSTRACT FROM AUTHOR]

Polysulfone membranes, used as contactors for CO2 capture, are blended with two different hyperbranched polyethyleneimines modified with benzoyl chloride (Additive 1) and phenyl isocyanate (Additive 2) in different percentages. Fourier‐transformed infrared spectra evidence the presence of urea and amide groups, whereas the field emission scanning electron microscopy images show differences in the microstructure of the blended membranes. Dielectric spectra determine the motions of the side and backbone chains, which can facilitate the diffusion of CO2. The spectra consist of six dielectric processes; three of them are due to the polysulfone (γPSf, βPSf, and αPSf), whereas the rest are characteristic of the additive (γHPEI, βHPEI, and αHPEI). The benzoyl chloride and phenyl isocyanate functional groups introduce variations in molecular mobility and modify the relaxations associated with the hyperbranched polyethyleneimine (HPEI). The additives also increase the conductivity of the blended membranes, which can compromise the performance of the membranes, specifically in the case of Additive 1. Ion hopping is found to be the prevailing charge transport mechanism while both relaxations, αHPEI and αPSf, are actives. These results, together with the final morphology of the membranes, may explain the greater absorption capacity of the membranes prepared with the hyperbranched polyethyleneimine modified with Additive 2. [ABSTRACT FROM AUTHOR]

In this study, determination of aromatic compounds in cheese samples was performed by headspace solid-phase microextraction (HS-SPME) using a new adsorbent as a novel coated fiber in combination with a gas chromatography/mass spectrometry or flame ionization detector to evaluate the changes during ripening. Brine and ultrafiltrated (UF) cheese were sampled via HS-SPME and analyzed by gas chromatography/mass spectrometry. Polysulfone and mesoporous carbon nitride were used as two types of fibers for coating. The results showed that the pH had significant decreased during the 120 days for brine cheese (p < 0.001), and during the 90 days (p < 0.001) for UF cheese. Acidity was relatively stable during the ripening period for both cheeses (p > 0.05). Protein content decreased during the ripening period for both cheeses (p < 0.001). Moisture content also significantly decreased during the ripening period for both cheeses (p < 0.001). 74 compounds were identified in brine cheese and 27 major components in UF cheese. Fatty acids were the predominant components, followed by aldehydes (n: 17, 22.9%), alcohol (n; 12, 16.2%), ester (n: 11, 14.8%), alkane (n: 7, 9.4%), and ketone (n: 6, 8.1%) for white brine cheese, while for UF cheese fatty acid (n: 12, 44.4%) and aldehyde (n: 5, 18.5%), alcohol (n: 3, 11.1%), ketone (n: 3, 11.1%), ester (n: 2, 7.4%) and alkane (n: 1, 3.7%). [ABSTRACT FROM AUTHOR]

The paper generalizes the information about the recent (from 2012) advances in the synthesis of aromatic sulfur-containing polymers, such as polyarylene sulfones, polyarylene sulfide sulfones, and their ethers. Their properties and application fields are described. The application of these polymers as proton- and anion-exchange membranes in fuel cells is considered in details. [ABSTRACT FROM AUTHOR]

Membrane technology has been extensively applied for protein separation. A membrane with reliable filtration performance and high removal efficiency is required. In this study, an ultrafiltration (UF) membrane was fabricated by dry‐wet phase inversion to incorporate copper oxide nanoparticles (CuO NPs) with a different ratio of L‐cysteine (Cys) in polysulfone (PSf). The characterization of the membrane involves using scanning electron microscopy (SEM), water contact angle, water content, pore size, and porosity analysis. The membrane performance evaluation includes flux permeation and bovine serum albumin (BSA) removal as a protein foulant. The membrane antifouling feature was examined by dynamic filtration of BSA. It was found that the Cys to CuO NPs ratio of 1.7:1 gives an optimal value on flux permeation and protein removal. The membrane exhibited high removal of BSA with 96.3%, and optimum water flux was achieved at 173.3 L/m2h, respectively. The highest permeability of aqueous BSA permeate at 500 ppm was about 111 L/m2h and 82.5 L/m2h for 1000 ppm. The enhancement of PSf‐Cys‐CuO membrane performance could be due to its lower contact angle (68.7°), high porosity (68%), and ideal pore size (46 nm) as well as showing good morphological structure. Most significantly, the inclusion of Cys improves antifouling capabilities. The membrane showed a lower chance of fouling based on the evaluation of the relative flux reduction and flux recovery ratio. Hence, the availability of Cys has a better impact on the polymer‐based membrane and seems promising for protein separation applications. [ABSTRACT FROM AUTHOR]

Annotation: High-strength and high-modulus carbon fibers are the basis of many composite materials used in power and automotive engineering as well as other mechanical engineering fields. Superstructural thermoplastic binders—like PPS, PSU, PES, and PEEK—are emerging quickly as a binder material. The mechanical properties of composite materials, especially tensile strength, are improved when high-strength and high-modulus fibers are combined with superstructural thermoplastic binders. However, the type of carbon fiber used, the concentration of thermoplastic binder, and the specifics of the production process all have a significant impact on the final mechanical properties of the composite material. As such, predicting these properties requires both a thorough analysis and a trustworthy mathematical model that predicts mechanical properties (tensile strength).The study that is being presented takes a thorough approach to statistical analysis and model building that anticipates the tensile strength of composite material samples made of carbon filaments that have been impregnated with polysulfone (PSU), a thermoplastic polymer.PSU thermoplastic polymer was used as a binder, and 817 samples of composite material with high-strength and high-modulus carbon fibers of four different grades were subjected to a thorough statistical analysis of the tensile test findings.Nine distinct regression models and four CNN-based models with three distinct neuron activation functions were constructed based on the statistical analysis. The built-in models forecast the composite material's ultimate strength based on the specimen loading circumstances, filler qualities, and composition.Significant differences were found in the mechanical properties of carbon fibers of different grades and types (high-strength and high-modulus) based on statistical analysis of the results of tensile tests. The results of Spearman's correlation study indicated a medium positive correlation between ultimate strength and polymer concentration and a weak negative association between ultimate strength and the density of the carbon fiber contained in the composite material. The strain corresponding to the ultimate strength and fiber density were found to have a medium negative correlation, whereas the polymer concentration showed a medium positive correlation. In the composite material, a very slight negative association was discovered between the concentration of polymers and the density of carbon fibers.Test results were split into two categories while creating CNN and regression models: 75 % were used for model testing and 25 % were used for training. The CNN model with three layers of hidden parameters produced the best prediction results; the RMSE was 142.948 MPa and the Spearman correlation coefficient between the test strength and the anticipated values was 0.988.Regression models' sensitivity analysis revealed that, up to a response variable (tensile strength) value of 0.75, fiber density has a greater influence than polymer density, with sample loading rate having the least impact. Beyond this point, fiber density essentially has no effect on tensile strength; polymer concentration and sample loading rate have the greatest effects. A minimal tensile strength at fiber density in the region of 0.1 of the maximum density and an abnormal decrease in tensile strength with increasing polymer concentration at the response variable value of 0.75 were discovered during the CNN model's sensitivity analysis. Additionally, it was discovered that, in contrast to other regression models, such as neural networks, the partial least squares model and LASSO are sensitive to the existence of groups in the data.To accomplish the specified structural features of tensile strength, the carbon fiber-PSU composite material production process' technological parameters can be optimized using the modeling and statistical analysis results that were acquired.

Polysulfone (Psf) and Cellulose acetate (Ac-Cel) based membranes were synthesized via immersion precipitation – phase inversion techniques, starting from initial polymeric solutions with concentrations of 8%, 10% and 12%. Each membrane was characterized from morphological point of view by scanning electronic microscopy and from compositional point of view by thermal analyses. Hydrodunamic characteristics were also determined for all membranes using both ultrapure water and real municipal wastewater. Obtained results proved that polysulfone and cellulose acetate based membranes are potential candidates to be used for advanced treatment of municipal wastewater using photocatalytic membrane reactors.

Polysulfone (Psf) ultrafiltration flat-sheet membranes were modified with hydroxyapatite (HA) powder during preparation using the wet-phase inversion method. HA was incorporated to enhance the protein separation capabilities. The asymmetric Psf membranes were synthesized using NMP as the solvent. Through Scanning Electron Microscopy (SEM) analysis, it was revealed that HA was distributed across the membrane. Incorporating HA led to higher flux, the improved rejection of protein, and enhanced surface hydrophilicity. The permeability flux increased with HA concentration, peaking at 0.3 wt.%, resulting in a 38% improvement to 65 LMH/bar. Whey protein separation was evaluated using the model proteins BSA and lysozyme, representing α-Lactalbumin. The results of protein rejection for the blend membranes indicated that the rejection rates for BSA and lysozyme increased to 97.2% and 73%, respectively. Both the native and blend membranes showed similar BSA rejection rates; however, the blend membranes demonstrated better performance in lysozyme separation, indicating superior selectivity compared to native membranes. The modified membranes exhibited improved hydrophilicity, with water contact angles decreasing from 66° to 53°, alongside improved antifouling properties, indicated by a lower flux decline ratio value. This simple and economical modification method enhances permeability without sacrificing separation efficiency, hence facilitating the scalability of membrane production in the whey protein separation industry.

As a promising wastewater treatment technology, ultrafiltration membranes face challenges related to fouling and flux reduction. To enhance these membranes, various strategies have been explored. Among them, the incorporation of nano-activated carbon (nAC) powder has emerged as an effective method. In this study, composite polysulfone (PSF) ultrafiltration membranes were fabricated using nAC powder at concentrations ranging from 0 to 8 wt.%. These membranes underwent comprehensive investigation, including assessments of membrane morphology, hydrophilicity, pure water flux, equilibrium water content, porosity, average pore size, and protein separation. The addition of activated carbon improved several desirable properties. Specifically, the hydrophilicity of the PSF membranes was enhanced, with the contact angle reduced from 69° to 58° for 8 wt.% of nAC composite membranes compared to the pristine PSF membrane. Furthermore, the water flux test revealed that 6 wt.% activated carbon-based membranes exhibited the highest flux, with a nearly 3 times improvement at 2 bar. Importantly, this enhancement did not compromise the protein rejection. Additionally, the introduction of nAC had a significant effect on the membrane’s pore size by improving lysozyme rejection up to 40%. Overall, these findings will guide the selection of the optimal concentration of nAC for PSF ultrafiltration membranes.

Response surface methodology (RSM) was used to find the best ratio in preparing the polysulfone (PSf) ultrafiltration (UF) membranes via phase inversion. The central composite design was used to make predictive regression models and study the effects of different parameters, such as the concentration of PSf polymer, the concentration of gum Arabic (GA), and the content of biosynthesized zinc oxide nanoparticles, on water flux, rejection, and porosity. Twenty tests were done to build a quadratic model, and the membranes were evaluated with scanning electron microscopy (SEM), atomic force microscopy (AFM), and water contact angle measurements. Using a Lab-scale cross-flow filtering device, performance testing was undertaken. The variance analysis showed that all three independent parameters were statistically important, and the model made from them was pretty good. To explain the regression equations, response surfaces, and outlines were plotted. The best experimental conditions were evaluated for water permeation flux, rejection, and porosity. The best parameters led to a maximum permeation flow of 381.5 L m−2 h−1, a rejection of 54%, and a porosity of 85.1%. With R2 values of more than 90%, the correlation between the measured and predicted values of pure water flux, rejection, and porosity values of the membranes validates the model's correctness. [ABSTRACT FROM AUTHOR]

Rapid social and industrial development has resulted in an increasing demand for fossil fuel energy, which increases particulate matter (PM) pollution. In this study, we employed a simple one-step electrospinning technique to fabricate polysulfone (PSF) fiber membranes for PM filtration. A 0.3 g/mL polymer solution with an N,N-dimethylformamide:tetrahydrofuran volume ratio of 3:1 yielded uniform and bead-free PSF fibers with a diameter of approximately 1.17 μm. The PSF fiber membrane exhibited excellent hydrophobicity and mechanical properties, including a tensile strength of 1.14 MPa and an elongation at break of 116.6%. Finally, the PM filtration performance of the PSF fiber membrane was evaluated. The filtration efficiencies of the membrane for PM2.5 and PM1.0 were approximately 99.6% and 99.2%, respectively. The pressure drops were 65.0 and 65.2 Pa, which were significantly lower than those of commercial air filters. Using this technique, PSF fiber membrane filters can be easily fabricated over a large area, which is promising for numerous air filtration systems. [ABSTRACT FROM AUTHOR]

Based on the preparation of chloromethylated polysulfone(CMPS), two types of sulfonated polysulfone, naphthalenesulfonic acid type sulfonated polysulfone(PS-NS) and pyrenesulfonic acid type sulfonated polysulfone(PS-TS) were successfully obtained via nucleophilic substitution with 2-naphthol-6,8-disulfonic acid dipotassium(NS) and 8-hydroxy-1,3,6-pyrene trisulfonic acid sodium(TS) as reagents, respectively. The PS-NS and PS-TS Proton exchange membranes (PEMs) were obtained by solution casting method after characterizing their structure by FT-IR and 1H-NMR. The impact of phenyl side chain on performance including water uptake(WU), swelling ratio(SR) and proton conductivity(PC) of PEMs were explored. Atomic force microscopy(AFM) shows that the phase separation structures of PS-NS and PS-TS PEMs are distinct due to the positioning of the hydrophilic sulfonic acid groups far away from the hydrophobic main chain. So the PS-NS and PS-TS PEMs keep excellent size stability, oxidative stability and methanol permeability at high WU. At the same bonding amount(BA) of sulfonic acid, due to less hydrophilic chain segment and a larger number of sulfonic acid groups in the hydrophilic chain segment, which is conducive to the aggregation of ion cluster. The PS-TS present better size stability and anti-oxidative at high WU. The SR of PS-TS-3 PEM was only 20.3 and 48.1%. Meanwhile, the methanol permeability was only 7.54 × 10−7cm2·s−1 at room temperature, much lower than commercialization Nafion115 PEM (16.8 × 10−7cm2/s at room temperature). The research results are of great significance for the design and preparation of high-performance membrane materials. [ABSTRACT FROM AUTHOR]

Solubility parameters are effective factors for controlling membrane preparation based on hydrophilic/hydrophobic polymers. Hansen solubility parameters (HSPs) of a polysulfone/polyethylene glycol (PSU/PEG) in increasing PEG molecular weights and binary coagulation bath of solvent/non-solvent mixtures are investigated. The results revealed that with increased PEG molecular weight in the casting solution, the relative energy difference (RED) of the solution increases, and subsequently its instability increases too. On the other hand, by increasing the solvent in the coagulation bath, RED decreases. Findings demonstrated that by increasing PEG molecular weight to 15,000 g /mol and increasing solvent to 60 wt% in the coagulation bath, an interconnected sponge-like structure with maximum mean pore size (120 nm) was achieved. With increased PEG molecular weight, membrane morphology tended toward to a sponge-like structure due to delayed demixing in the phase inversion stage. Furthermore, pure water permeability and rejection capability of membranes exhibited that with increasing RED of casting solution and reducing RED of coagulation bath, the highest permeability (2199 L/m2h and the lowest rejection capability (33%) of the membrane were attained. This study confirmed that, for the PSU/PEG system, by controlling the solubility parameters, RED value of casting solution and coagulation bath, membrane characteristics can be controlled. [ABSTRACT FROM AUTHOR]

Phase equilibria, interdiffusion and structure in the initial uncured mixtures of epoxy oligomer–polysulfone–alkyl glycidyl ether were studied. Binodal curves were constructed on isothermal sections of the ternary phase diagram. Thermodynamic mixing parameters were calculated and spinodal curves were plotted. The interdiffusion coefficients of components, establishing the technological modes of mixing the components, were determined. To validate the phase diagram, the phase structure of mixtures, the composition of which at a temperature of 40 °C corresponds to heterogeneous and homogeneous regions, was studied. [ABSTRACT FROM AUTHOR]

The paper is devoted to the study of thermal and mechanical behavior and structural features of the polysulfone solution impregnated unidirectional carbon fiber yarns depending on fabrication conditions and appearance for optimum production method of the composites. The effect of producing conditions, such as polysulfone solution concentration, drying and post-heating temperatures, and the residual solvent content on the structure, mechanical, and thermal properties of the carbon fiber-reinforced composites was studied. The polysulfone solution impregnated carbon fiber yarns show relatively high mechanical properties, realizing up to 80% of the carbon fibers' tensile strength, which can be attributed to good wettability and uniform polymer matrix distribution throughout the entire volume of the composites. It was found that the composites impregnated with 40 wt.% of the polysulfone solution showed lower porosity and higher mechanical properties. The results of a dynamic mechanical analysis indicate that residual solvent has a significant effect on the composites' thermal behavior. The composites heated to 350 °C for a 30 min showed higher thermal stability compared to ones dried at 110 °C due to removal of residual solvent during heating. The impregnated carbon fiber yarns can be used for the further producing bulk unidirectional composites by compression molding and the proposed method can be easily transformed to continuous filament production, for example for further use in 3-D printing technology. [ABSTRACT FROM AUTHOR]

Blend membranes of polycarbonate and polysulfone were studied for removal of bovine serum albumin (BSA) from water. The membranes were prepared by blending (1–10) wt.% of polysulfone with polycarbonate and then non-solvent induced phase separation (NIPS) of blend solutions. Structural analysis, thermal and tensile properties, water uptake, porosity, water contact angle, and morphological studies were conducted. Water treatment performance of membranes were tested in a crossflow system in terms of pure water flux, rejection, and fouling. BSA rejection value was improved from 85.65% to 92.88% for polycarbonate membrane in the presence of 10 wt.% polysulfone. [ABSTRACT FROM AUTHOR]

Polymer blending has attracted considerable attention because of its ability to overcome the permeability–selectivity trade-off in gas separation applications. In this study, polysulfone (PSU)-modified cellulose acetate (CA) membranes were prepared using N-methyl-2-pyrrolidone (NMP) and tetrahydrofuran (THF) using a dry–wet phase inversion technique. The membranes were characterized using scanning electron microscopy (SEM) for morphological analysis, thermogravimetric analysis (TGA) for thermal stability, and Fourier transform infrared spectroscopy (FTIR) to identify the chemical changes on the surface of the membranes. Our analyses confirmed that the mixing method (the route chosen for preparing the casting solution for the blended membranes) significantly influences the morphological and thermal properties of the resultant membranes. The blended membranes exhibited a transition from a finger-like pore structure to a dense substructure in the presence of macrovoids. Similarly, thermal analysis confirmed the improved residual weight (up to 7%) and higher onset degradation temperature (up to 10 °C) of the synthesized membranes. Finally, spectral analysis confirmed that the blending of both polymers was physical only. [ABSTRACT FROM AUTHOR]

The performances of polybenzimidazole (PBI) and polysulfone (PSF) membranes for recovering water from reverse osmosis (RO) reject of brackish water through forward osmosis (FO) were assessed and compared. Non-functionalised multi-walled carbon nanotubes (MWCNT) were added to the membrane casting solutions, with concentrations ranging from 0 to 3 wt%. The experiment was conducted for eight samples using RO reject of brackish water as the feed solution (FS) and 2 M analytical grade MgCl2 as the draw solution (DS). The hydrophilicity, water permeability, salt rejection rate (Rs), water flux (WF) and porosity of the membranes improved with increasing MWCNT content up to 2 wt%. Also, the structural parameter, salt permeability and reverse solute flux decreased. PBI/MWCNT2 wt% exhibited the best performance among the membranes tested compared with porosity of 70 ± 4 %, structural parameter of 0.36 ± 0.2 μm, and Rs of 93.5 %. In contrast with the pristine PBI membrane, an average water flux enhancement of 15 % and 49 % was observed for the FS and DS sides, respectively, for PBI/MWCNT2 wt%. It is evident from the results that including MWCNT improves the performance of both membranes, with better relative performance for PBI membranes than PSF membranes.

At the moment, there is a growing interest in composite materials with matrices based on thermoplastic polymers; these materials are superior to traditional carbon fiber plastics due to higher fracture toughness and impact strength, low smoke generation during combustion, and high thermal and chemical resistance. The deformation behavior of such composite materials due to the high plastic deformation of the matrix differs from the behavior of traditional composites, which must be considered when performing calculations. In our study, as a model object, the features of the microstructure of single carbon thread impregnated with polysulfone were studied in order to evaluate the distribution of misorientation angles of elementary fibers, the degree of their damage, the thickness of the polymer matrix interlayers between elementary fibers in threads impregnated with more viscous thermoplastic binders. Statistical analysis of a large array of micrographs was carried out using specially developed algorithms for computer processing of electron microscopic images of a composite material. Algorithms for processing arrays of images using machine vision algorithms are proposed. Based on the analysis of the data array, the distributions of carbon fibers impregnated with polysulfone were plotted over the misorientation angle of the filaments and over the interfilament distance in the longitudinal and cross sections of the fiber. Using the machine learning method, an algorithm for detecting violations of the filament structure was implemented. The data obtained can be used to refine the calculations of the strength and deformation characteristics of composite materials with thermoplastic matrices.

Polymer blending has attracted considerable attention because of its ability to overcome the permeability–selectivity trade-off in gas separation applications. In this study, polysulfone (PSU)-modified cellulose acetate (CA) membranes were prepared using N-methyl-2-pyrrolidone (NMP) and tetrahydrofuran (THF) using a dry–wet phase inversion technique. The membranes were characterized using scanning electron microscopy (SEM) for morphological analysis, thermogravimetric analysis (TGA) for thermal stability, and Fourier transform infrared spectroscopy (FTIR) to identify the chemical changes on the surface of the membranes. Our analyses confirmed that the mixing method (the route chosen for preparing the casting solution for the blended membranes) significantly influences the morphological and thermal properties of the resultant membranes. The blended membranes exhibited a transition from a finger-like pore structure to a dense substructure in the presence of macrovoids. Similarly, thermal analysis confirmed the improved residual weight (up to 7%) and higher onset degradation temperature (up to 10 °C) of the synthesized membranes. Finally, spectral analysis confirmed that the blending of both polymers was physical only.

This work discussed the fabrication of polysulfone (PSF) ultrafiltration membranes with hydrophilic behaviour by adding branched polyethyleneimine (PEI) as an additive. By directly blending the base polymer and the additive in the organic solvent, the casting solution is prepared. An asymmetric ultrafiltration membrane was fabricated by the phase inversion method. The presence of PEI was confirmed by comparing the IR spectra of the plain PSF membrane and the modified PSF membrane. A scanning electron microscope was used for the comparison of morphological changes in plain and modified membranes. The membrane was characterised with respect to bovine serum albumin (BSA) adsorption, pure water flux, permeability, compaction factor, humic acid (HA) rejection, and water uptake. The fouling resistance behaviour is prompted due to the presence of hydrophilic PEI chains in the membrane. As a result, pure water flux and flux recovery ratio increased from 28.84 to 326.54 L/m2h and from 0.526 to 0.954 L/m2hkPa for the modified membrane with respect to the plain membrane, respectively. HIGHLIGHTS Polysulfone (PSF) ultrafiltration membranes with hydrophilic behaviour by adding the polyethyleneimine branched (PEI) as an additive were fabricated.; High percentage of HA rejection was achieved with good antifouling properties.; BSA adsorption also decreased with respect to the weight percentage of PEI.;