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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]

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]

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]

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]

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]

Oxidative stress is highly prevalent in maintenance hemodialysis patients and increases the risk of cardiovascular morbidity and mortality. Silymarin (SM) is a natural compound extracted from plants, and has been shown to have pharmacological effects such as antioxidant, anti‐inflammatory, cytoprotective, and anti‐nephrotoxicity. SM‐modified polysulfone (PSF) hemodialysis membranes were prepared by an immersion‐precipitation phase transition method. The experimental results showed that the modified membranes effectively scavenged free radicals, significantly inhibited lipid peroxidation, and had good antioxidant stability (60 days). The PSF/SM antioxidant membranes (H‐3) had no pro‐inflammatory effect, which was confirmed by the result of anti‐M1 macrophage polarization. Furthermore, the hemolysis rate (2%), blood cell deformation (3.7%), and inhibition of erythrocyte and platelet adhesion were improved by the SM‐modified PSF membranes. All the results suggest that PSF/SM blended hollow fiber membranes are promising for application in hemodialysis membranes to improve oxidative stress status and reduce inflammation and complications in patients. [ABSTRACT FROM AUTHOR]

Membranes are employed in various applications, including pharmaceutical waste separation, owing to their operability, high removal capacity, and cost‐effectiveness. However, membrane fouling is an influential factor that reduces their efficiency. Since the addition of hydrophilic inorganic components has been shown to reduce membrane fouling, the present work focuses on manganese (MnO2, Mn2O3) nanoparticles (NP) in polysulfone (PSF) casting solutions to prepare mixed‐matrix membranes for separating diclofenac (DCF) sodium from an aqueous solution. The membranes were characterized using microscopic and spectroscopic techniques, thermogravimetric analysis, and by elucidating the internal membrane specific area, contact angle, and mechanical properties. The synthesized NP were characterized by X‐ray diffraction and transmission electron microscopy analysis. The concentrations of DCF sodium measured in the feed and filtrate solutions showed that the PSF/Mn2O3 membrane provided the highest permeate flux with good DCF removal of 98.4 %. Mechanical testing indicated that higher tensile strength was obtained when embedding MnO2 NP in the PSF membrane matrix. Contact angle measurements showed an improvement of the surface hydrophilicity when blending the PSF casting solution with MnO2 NP. The fouling test indicated that the PSF/Mn2O3 membrane provided the best antifouling properties. Thus, NP addition enhanced the porosity, antifouling characteristics, hydrophilicity, and water flux of the fabricated membranes. [ABSTRACT FROM AUTHOR]

This paper presents a novel method to construct a membrane formation system featuring a low critical solution temperature (LCST) by incorporating hydroxy terminated hyperbranched polyester (HBPE) into polysulfone (PSF) casting solution. PSF membranes were developed by modified reverse thermally induced phase separation (m‐RTIPS) process while the introduction of HBPE improved the hydrophilicity of the membrane. The critical properties of the flat‐sheet PSF membranes were discussed in detail. The cloud point decreased as the HBPE concentration was increased. When membranes were prepared via m‐RTIPS, the region of bicontinuous finger‐like pores in the sublayer gradually broadened. The membranes showed better permeation properties, larger pore size, and better mechanical properties than those of the membranes prepared via non‐solvent‐induced phase separation (NIPS) process. Furthermore, no matter the enhanced hydrophilicity of membrane or m‐RTIPS membrane‐forming mechanism was beneficial to the anti‐fouling properties. In general, the membrane MPSF‐8‐b had relatively high flux, good hydrophilicity and excellent mechanical properties at 0.8 wt.% HBPE content, and the pure water flux recovery of the membrane was increased to 55.2%. [ABSTRACT FROM AUTHOR]

Durable, robust, and hydrophobic air filtration media was produced via electro‐blow spinning (EBS) technique using polysulfone (PSU) due to its superior properties. To our knowledge, this is the first optimization study of PSU nanofiber production via EBS technique for air filtration applications. Concentration, air pressure, and voltage were determined as independent variables for the optimization based on "smaller is the better" approach of Taguchi Design of Experiment. The optimized values which supplied the smallest average fiber diameter (AFD) possible were obtained as 13 wt% PSU, 3 bar, and 7.5 kV. The AFD of the sample obtained from the confirmation experiment was calculated as 105 ± 34 nm. Surface morphologies, porosity values, and wettability behaviors of the samples were investigated by using scanning electron microscopy, gravimetric method, and water contact angle measurements, respectively. PSU nanofiber mats exhibited superhydrophobic behavior (water contact angle values up to 159.8°) which is important for various separation processes. Samples prepared at different deposition times (15, 30, 45, and 60 min) were investigated in terms of particle capture efficiency and pressure drop. The 0.3 μm particle filtration efficiency was found to be 98.09% at an expense of 202 Pa pressure drop which would be suitable for various respiratory and HVAC filter applications. [ABSTRACT FROM AUTHOR]

In the present study, a simple, inexpensive, nontoxic, and environmentally friendly polyethylene glycol (PEG) polymer was used to enhance the hydrophilicity of the forward osmosis (FO) membrane using various PEG concentrations as a pore forming agent in the casting solution of polyethersulfone/polysulfone (PES/PSF) blend membranes. A nonwoven PES/PSF FO blend membrane was fabricated via the immersion precipitation phase inversion technique. The membrane dope solution was cast on polyethylene terephthalate (PET) nonwoven fabric. The results revealed that PEG is a pore forming agent and that adding PEG promotes membrane hydrophilicity. The membrane with 1 wt% PEG (PEG1) had about 27% lower contact angle than the pristine blend membrane. The PEG1 membrane has less tortuosity (which reduces from 3.4–2.73), resulting in a smaller structure parameter (S value) of 277 μm, due to the presence of open pores on the bottom surface structure, which results in diminished ICP. Using 1 M NaCl as the draw solution and distilled water as the feed solution, the PEG1 membrane exhibited higher water flux (136 L m−2 h−1) and lower reverse salt flux (1.94 g m−2 h−1). Also, the selectivity of the membrane, specific reverse salt flux, (Js/Jw) showed lower values (0.014 g/L). Actually, the PEG1 membrane has a 34.6% higher water flux than the commercial nonwoven‐cellulose triacetate (NW‐CTA) membrane. By means of varied concentrations of NaCl salt solution (0.6, 1, 1.5, and 2 M), the membrane with 1 wt% PEG showed improved FO separation performance with permeate water fluxes of 108, 136, 142, and 163 L m−2 h−1. In this work, we extend a promising gate for designing fast water flux PES/PSF/PEG FO blend membranes for water desalination. [ABSTRACT FROM AUTHOR]

Carbon dioxide separation from flue gases is an important challenge to be faced. Membrane processes are a promising alternative to increase technical and economical constraints once the development of materials with superior characteristics are attained. Integrally asymmetric mixed matrix membranes (MMMs) were prepared by dry/wet phase inversion process of polysulfone (PSF) containing oxygen‐functionalized multiwalled carbon nanotubes (MWNT‐O). Fourier transform infrared (FTIR) spectroscopy confirmed the presence of MWNT‐O in MMMs. Thermal gravimetric analysis (TGA) showed that MMMs are stable up to 150°C. Photomicrographs from scanning electron microscopy (SEM) revealed that MMMs consist of an asymmetric structure with a skin layer supported on a sponge‐like substructure. The pore size of the support of MMMs increased with MWNT‐O content from 0.4 to 0.8 wt.% and the thickness of the dense layer decreased. However, when the content of MWNT‐O increased to 1 wt.%, the pore size decreased, and the dense layer increased. Therefore, MMMs changed CO2 separation performance. For 1 wt.% MWNT‐O loading compared to the neat polymer, CO2 permeance and CO2/N2 selectivity was increased from 1.5 to 2.7 GPU, and from 9.5 to 14.3, respectively. [ABSTRACT FROM AUTHOR]

Vat photopolymerization (VP) is an advanced additive manufacturing (AM) platform that enables production of intricate 3D monoliths that are unattainable with conventional manufacturing methods. In this work, modification of amorphous poly(arylene ether sulfone)s (PSU) allows for VP printing. Post‐polymerization telechelic functionalization with acrylate functionality yielded photocrosslinkable PSUs across a molecular weight range. 1H NMR spectroscopy confirms chemical composition and quantitative acrylate functionalization. Addition of diphenyl‐(2,4,6‐trimethylbenzoyl)phosphine oxide (TPO) photoinitiator to 30 wt% PSU solutions in NMP provides a photocurable composition. However, subsequent photorheological studies elucidate rapid photodegradation of the polysulfone main chain, which is especially apparent in high Mn (15 kg mol−1) PSU formulations. UV‐light intensity and wavelength range are altered to reduce degradation while allowing for efficient crosslinking. The addition of 0.5 wt% of avobenzone photoblocker produces an ill‐defined structure with 6 kg mol−1 PSU. For higher molecular weights (>12 kg mol−1), solutions with a low molar mass reactive diluent, i.e., trimethylolpropane triacrylate, enable the printing of an organogel with a storage modulus (>105 Pa) sufficient for vat photopolymerization. Employing multicomponent solutions provide well‐defined parts with complex geometries through vat photopolymerization. [ABSTRACT FROM AUTHOR]

In this article, the nanofillers of graphene oxide (GO) and cellulose nanocrystal (CNC), which called GC, was prepared. The X‐ray photoelectron spectrometer (XPS), Raman spectra, thermogravimetric analysis (TGA) and transmission electron microscopy (TEM) were carried out for its characterizations. Besides, its influences on mechanical properties, thermal stability and gas barrier properties of polysulfone (PSF) composites were also studied. The hydrophilic interaction occurs between GO and CNC, so that CNC repaired the structural defects of GO. The intensity ratio of D peak to G peak (ID/IG) in Raman spectra of GC was 0.96, which was less than the raw GO's ID/IG of 1.04. Compared with GO, GC could more effectively improve the tensile strength (+39.8%), elongation‐at‐break (+20.6%), Young's modulus (+30.7%), thermal decomposition temperature (+13°C) and O2 permeability (−95.2%) of PSF composites. At the content of 0.5 wt%, GC had the most significant effect on the performance of PSF composites. [ABSTRACT FROM AUTHOR]

High‐performance engineering polymers continually challenge existing boundaries of rapidly emerging research areas including electronics, transportation, energy, defense and aerospace. Significant research attention over the past decade highlights the exceptional performance of these polymers due to their superior thermomechanical properties and stability under extreme conditions. Unfortunately, inherent structure–property relationships of high‐performance engineering polymers, which predict this unique complement of physical properties, also describe high‐viscosity melts and high melting temperatures. These processing challenges have steered researchers towards advanced processing methods, such as additive manufacturing, that allow for unprecedented control over part geometry. In addition, additive manufacturing serves to advance application–cost relationships, as part optimization and 3D printing of previous monolithic components allow for less material consumption. Currently, the additive manufacturing materials toolbox only contains a fraction of commercially available high‐performance polymers due to unique processing constraints. This review discusses recent efforts towards the successful additive manufacturing of three high‐performance polymer families, i.e. polysulfones, poly(ether ether ketone)s and polyimides. © 2021 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

This work reports the synthesis of silver nanoparticles from the precursors, silver nitrate and sodium bromide, and the in situ synthesis of polysulfone (PSf)‐poly(ethylene‐glycol) (PEG) block copolymer (BCP) in the presence of developed Ag. The PSf‐PEG BCP nanocomposite containing 3 wt.% of the nanoparticles, when electrospun, is observed to be helpful in separating the oil‐in‐water emulsion. Mechanical properties such as dynamic mechanical strength and tensile strength measurements and high thermal degradation temperature (~6°C) illustrate the reinforcing effect of the Ag nanoparticles. The presence of Ag influences the glass transition temperature (Tg) of the BCP and its elasticity due to its well distribution in the BCP during the in situ synthesis of nanocomposite. Electrospun fiber mat of the in situ synthesized PSf‐PEG/Ag nanocomposite shows improved wettability as evident from the respective aqueous contact angle values of 80.66° ± 1.3, 85.70° ± 2.0, and 101.50° ± 1.0 for PSf‐PEG/Ag, PSf‐PEG, and neat PSf. The combination of PEG to PSf has increased the overall polymer reinforcement effect, and this property along with the antimicrobial activity (inhibited growth of Staphylococcus aureus) of Ag nanoparticles are applied in developing bio‐fouling resistant BCP nanocomposite fibers for oil/water emulsion separation. [ABSTRACT FROM AUTHOR]

Polysulfone (PSU) is a suitable material for industrial gas separation. In the present study, it was possible to produce PSU flat membranes with a porous support structure and a separating top layer in the micrometer range in one step using special casting solutions and the dry/wet phase inversion process. By varying the composition of the casting solution and the precipitant, the characteristics of the individual PSU layers was varied. Scanning electron microscope images were taken to demonstrate the layer structures of the PSU flat membranes. The gas separation properties (permeabilities and ideal selectivities) were characterized by gas permeation measurements. [ABSTRACT FROM AUTHOR]

In the current study, a phase inversion scheme was employed to fabricate hydroxyapatite (HA)/polysulfone (PSF)‐based asymmetric membranes using a film applicator with water as a solvent and nonsolvent exchanging medium. Fourier Transform Infrared (FTIR) and X‐ray diffraction (XRD) spectroscopic studies were conducted to confirm the bonding chemistry and purity of filler. The inherent thick nature of PSF generated sponge‐like shape while the instantaneous demixing process produced finger‐like pore networks in HA/PSF‐based asymmetric membranes as exhibited by scanning electron microscope (SEM) micrographs. The FTIR spectra confirmed noncovalent weak attractions toward the polymer surface. The leaching ratio was evaluated to observe the dispersion behavior of HA filler in membrane composition. Hydrophilicity, pore profile, pure water permeation (PWP) flux, and molecular weight cutoff (MWCO) values of all formulated membranes were also calculated. Antifouling results revealed that HA modified PSF membranes exhibited 43% less adhesion of bovine serum albumin (BSA) together with >86% recovery of flux. Membrane composition showed 74% total resistance, out of which 60% was reversible resistance. Biocompatibility evaluation revealed that the modified membranes exhibited prothrombin time (PT), and thrombin time (TT) comparable with typical blood plasma, whereas proliferation of living cells over membrane surface proved its nontoxic behavior toward biomedical application. The urea and creatinine showed effective adsorption aptitude toward HA loaded PSF membranes. [ABSTRACT FROM AUTHOR]

Introduction: Hydrophilic modification with polyvinylpyrrolidone (PVP) increases the biocompatibility profile of synthetic dialysis membranes. However, PVP may be eluted into the patient's blood, which has been discussed as a possible cause for adverse reactions rarely occurring with synthetic membranes. We investigated the content of PVP and its elution from the blood‐side surface from commercially available dialyzers, including the novel FX CorAL, with PVP‐enriched and α‐tocopherol‐stabilized membrane, and link the results to the level of platelet loss during dialysis as a maker of biocompatibility. Methods: Six synthetic, PVP containing, dialyzers (FX CorAL, FX CorDiax [Fresenius Medical Care]; Polyflux, THERANOVA [Baxter]; ELISIO [Nipro]; xevonta [B. Braun]) were investigated in the present study. The content of PVP on blood‐side surface was determined with X‐ray photoelectron spectroscopy (XPS). The amount of elutable PVP was measured photometrically after 5 h recirculation. The level of platelet loss was evaluated in an ex vivo recirculation model with human blood. Findings Highest PVP content on the blood‐side surface was found for the polysulfone‐based FX CorAL (26.3%), while the polyethersulfone‐based THERANOVA (15.6%) had the lowest PVP content. Elution of PVP was highest for the autoclave steam‐sterilized THERANOVA (9.1 mg/1.6 m2 dialyzer) and Polyflux (9.0 mg/1.6 m2 dialyzer), while the lowest PVP elution was found for the INLINE steam sterilized FX CorAL and FX CorDiax (<0.5 mg/1.6 m2 dialyzer, for both). Highest platelet loss was found for xevonta (+164.4% compared to the reference) and the lowest for the FX CorAL (−225.2%) among the polysulfone‐based dialyzers; among the polyethersulfone‐based dialyzers, THERANOVA (+95.5%) had the highest and ELISIO (−52.1%) the lowest platelet loss. Discussion Polyvinylpyrrolidone content and elution differ between commercially available dialyzers and were found to be linked to the membrane material and sterilization method. The amount of non‐eluted PVP on the blood‐side surface may be an important determinant for the biocompatibility of dialyzers. [ABSTRACT FROM AUTHOR]

Toray has created a new generation of dialyzers, the polysulphone (TS) UL series, and polymethylmethacrylate (PMMA) NF‐U series, which offer enhanced efficacy over the previous TS‐S series and NF‐H series. The aim of this study was to evaluate the safety and efficacy of these dialyzer series versus contrasted expanded hemodialysis (HDx) and postdilution hemodiafiltration (HDF). We conducted a prospective study in 12 patients. Each patient underwent six dialysis sessions: FX80 Cordiax in HD, Toraysulfone TS‐1.8 UL in HD, Theranova 400 in HDx, polymethylmethacrylate (PMMA) NF‐2.1 U in HDF, Toraysulfone TS‐2.1 UL in HDF, and FX80 Cordiax in HDF. The removal ratios (RRs) of urea, creatinine, ß2‐microglobulin, myoglobin, prolactin, α1‐microglobulin, α1‐acid glycoprotein, and albumin were compared intraindividually. Dialysate albumin loss was also measured. The RRs for β2‐microglobulin, myoglobin, prolactin, α1‐microglobulin, and α1‐acid glycoprotein were higher with the TS‐2.1 UL and FX80 Cordiax dialyzers in HDF than those obtained with HD treatments and NF‐2.1 U in HDF. The β2‐microglobulin, myoglobin, and prolactin RRs were also higher with HDx than those obtained with HD treatments. The myoglobin and prolactin RRs were higher with TS‐1.8 UL in HD than those obtained with helixone dialyzers in HD. Dialysate albumin loss was less than 3 g in all situations except in TS‐2.1 UL in HDF. The highest global removal score values were obtained with the TS‐2.1 UL and helixone dialyzers in HDF. Significant differences were found between all study situations. In conclusion, the new generation dialyzers, Toraysulfone TS Series UL and PMMA NF‐U series, show excellent behaviour and tolerance in HD and HDF, representing an upgrade versus their predecessor series. The higher permeability of the TS UL series has been proven with higher efficiency in HD and maximum performance in HDF. The new PMMA NF‐U series allows the use of HDF with good efficiency and complete safety. [ABSTRACT FROM AUTHOR]

Carbonate apatite/hydroxyapatite (CO3Ap/HAP) additive was obtained by calcination of wasted chicken bones at 900°C. Intermolecular attraction exists between CO3Ap/HAP additive and blended polysulfone (PSF) polymer. Electron dispersive X‐ray (EDX) and FTIR analysis were carried out to check the elemental composition and bonding chemistry of prepared additive. The instantaneous demixing process generated consistent finger‐like networks in CO3Ap/HAP/PSF‐based composite membranes while sponge‐like structure was shown by PSF as revealed by SEM images. The increase in weight % of additive loading is also confirmed by EDX analysis. Furthermore, the interaction mechanism of CO3Ap/HAP additive with polysulfone medium was analyzed by FTIR exploration. The water absorption experiment defined a 93% expansion in hydrophilic performance. Change in porosity occurs with additive loading and pure water permeation flux improved up to 11 times. Approximately, antifouling results revealed that 87% of water flux was recovered after treating with a protein solution, whereas a 30% improvement in antifouling capability in case of bovine serum albumin solution occurred. In vitro cytotoxicity, and clotting times study was carried out to evaluate virulent behavior and anticoagulation activity of formulated membranes. [ABSTRACT FROM AUTHOR]

In recent decades, the flame retardancy of wigs has improved by combining polymer fibers and flame retardants. Halogen‐based retardants suppress combustion through a radical trap; however, they are harmful to humans and to the environment. Thus, in this study, black wigs were prepared by polysulfone (PSU)‐based fibers through melt spinning process and were compared to that prepared by poly(ethylene terephthalate) (PET)‐based fibers. Different types and amounts of carbon black added during the melt spinning process to produce its color were also investigated to assess its effects on the manufactured wig. The flame retardancy of PSU and PET fibers was evaluated using limited oxygen index (LOI) measurement. The LOI of PET fiber was 24%, while that of PSU fiber was 29%, confirming its highly flame‐retardant behavior. Based on its mechanical properties (tenacity and elongation), PSU fibers (1.5 g/den) are more suitable for artificial human hair due to its higher tenacity than PET fibers (0.8 g/den). The addition of a small amount of carbon black (<0.5 wt%) did not negatively affect the produced wig; thus, a highly flame‐retardant black wig with superior mechanical properties was obtained. [ABSTRACT FROM AUTHOR]

Solution blow spinning (SBS) is used to prepare polysulfone materials (PSf) with different morphologies changing the processing conditions. Morphological study is done by scanning electron microscopy. Materials mainly constituted by beads and fibers are obtained. An optimization strategy based on desirability function approach together with Box–Behnken design is employed to find the best processing conditions to produce PSf materials with tailored morphology. Feed rate and air pressure are the variables of SBS processing conditions with the highest influence on the relative amount of fibers produced while air pressure and a particular balance between work distance and feed rate have the highest impact on the size of fibers. Contact angle measurements are used to understand SBS PSf wettability as a function of morphology. It is demonstrated the possibility of designing PSf materials with particular wettability behavior induced by tailored morphologies obtained from a particular election of SBS processing conditions. [ABSTRACT FROM AUTHOR]

Magnetic mixed‐matrix membranes (MMMs) are fabricated using polysulfone (PSf) and iron oxide (Fe) for O2/N2 separation. The effects of Fe nanoparticle size and content on the performance of the membranes are investigated using a novel gas permeation unit in the presence of various magnetic fields. The results indicate that the O2 permeation is improved by adding Fe nanoparticles into the PSf matrix regardless of the particle size. Furthermore, the selectivity of PSf and PSf‐Fe membranes is considerably enhanced by applying a magnetic field during the permeation experiments. The O2 permeability and O2/N2 selectivity of PSf‐Fe50 MMMs in the presence of a magnetic field are higher than those of neat PSf membranes. [ABSTRACT FROM AUTHOR]

Multiwalled carbon nanotubes (MWCNTs)‐containing polysulfone (PSf) mixed matrix membranes (MMM) are prepared using phase inversion by immersion precipitation. MWCNT are functionalized with oxygen groups to allow the dispersion of the filler in the polymer solution. Membranes with 0, 1, 3 and 5% w/w MWCNTs in PSf are prepared. The addition of the filler changed the permeability of pure PSf. The best results are found for the 1 wt% membrane, with increase in CO2 permeability of 660% and ideal selectivity CO2/N2 of 547%. The MMM also exhibited good thermal stability for gas separation. DSC and SEM results revealed that the addition of 1wt% of the filler caused changes in chain arrangements and membrane morphology. [ABSTRACT FROM AUTHOR]

Incorporation of inorganic fillers into Polysulfone (PSF) to constitute mixed matrix membranes (MMMs) has become a viable solution to prevail over limitations of the pristine materials in natural gas sweetening process. Nevertheless, preparation of MMMs without defects and empirical investigation of membrane that exhibits characteristic of improved CO2/CH4 separation performance at experimental scale are difficult that require prior knowledge on compatibility between the filler and polymer. A computational framework has been conducted to construct validated PSF based MMMs using silica (SiO2) as inorganic fillers. It is known that nanosized SiO2 can coexist in varying polymorph configurations (ie, α‐Quartz, α‐Cristobalite, α‐Tridymite) but molecular simulation study of SiO2 polymorphs to form MMMs is limited. Therefore, this work is a pioneering study to elucidate feasibility in facile utilization of polymorphs to improve gas separation performance of MMMs. Physical properties and gas transport behavior of the simulated PSF based MMMs with different SiO2 polymorphs and loadings have been elucidated. The optimal MMM has been found to be PSF/25 wt% α‐Cristobalite at 55°C. The success in molecular simulation has shed light on how computational tools can provide understandings at molecular level to elucidate compatibility between varying pristine materials to MMMs for natural gas processing. [ABSTRACT FROM AUTHOR]

Making a nanocomposite membrane is an effective way of producing membranes with desired functionality, better permeance. In this work, virgin polysulfone ultrafiltration (UF) membrane and nanocomposite membranes with different concentrations ranging from 100 to 2,000 mg/L iron–nickel oxide in polysulfone matrix were prepared by phase inversion method. The performances of prepared membranes were evaluated by pure water permeance testing, protein rejection, and lead rejection. Up to 99.66% removal of lead was achieved by nanocomposite membrane. The structure and property of membranes were analyzed by scanning electron microscopy (SEM), powder X‐ray diffractometer (XRD), and atomic force microscopy (AFM) and zeta potential analysis. The nanocomposite membranes showed higher water permeance as compared to virgin ultrafiltration membrane. The membrane with 750 mg/L concentration of iron–nickel oxide nanoparticle demonstrated the increase in water flux by 117.85% as compared to the virgin ultrafiltration membrane. Higher albumin rejection and lead rejection were achieved by nanocomposite membrane as compared to polysulfone membrane. Leaching study of nanomaterial in water was undertaken, and it was found the leaching of nanomaterial was minimal. Increase in surface roughness, increase in number of pores with decrease in pore size, led to improvement in ultrafiltration performance by increased selectivity and permeance of the membrane. © 2020 Water Environment Federation Practitioner points: The nanocomposite ultrafiltration membrane with iron–nickel oxide nanomaterial.Upto 117.85% increase in pure water permeance as compared to virgin membrane.Upto 99.66% lead rejection and upto 96.8% albumin rejection from aqueous solution.Little or no leaching of nanomaterials in water.Increased selectivity and productivity of membrane. [ABSTRACT FROM AUTHOR]

Bead‐on‐string is a desirable morphology for some emerging applications of electrospun mats such as superhydrophobic surfaces. In this study, the bead‐on‐string morphology in electrospun polysulfone (PSU) mats was investigated and correlated with the solution concentration, voltage and feed rate. PSU/dimethylformamide solutions with different concentrations (4, 5.5, 7, 15, 18 and 20 wt% PSU) were electrospun at a constant feed rate (3.5 mL h–1) and voltage (15 kV). Critical chain overlap and entanglement concentrations were found to be 3.65 and 7.12 wt% PSU, respectively. The bead‐on‐string morphology was detected in the concentration range 7–18 wt% PSU, in close agreement with theoretical estimations. The evolution of the bead‐on‐string morphology in mats prepared from 15 wt% PSU solution and electrospun at three feed rates (i.e. 1.5, 2.5 and 3.5 mL h–1) and voltages (i.e. 12.5, 15 and 18 kV) were also studied. The results showed that the beads appear less in number as either the feed rate or the voltage increases. In addition, the morphology of the beads revealed a transition from a spherical to a spindle‐like appearance with an increase in voltage. The effect of feed rate on bead geometry, however, was revealed to depend on the applied voltage. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In this work, mixed matrix membranes based on polysulfone containing different contents of graphene oxide were prepared using a phase inversion process. The morphological, and structural properties as well as surface features of the samples were investigated by means of field‐emission scanning electron microscopy, infrared and x‐ray diffraction spectroscopies, as well as atomic force microscopy. The gas permeation/selectivity behavior of graphene oxide‐loaded polysulfone samples was studied using pure carbon dioxide, and methane. Morphological images depicted that the addition of graphene oxide to polysulfone in the presence of isopropyl alcohol as non‐solvent was reduced the numbers of finger‐like macro‐voids, and caused to the formation of teardrop‐like structures. Besides the x‐ray patterns and Fourier transform infrared spectra confirmed the graphene oxide nano‐plates and polysulfone with no chemical interactions, the atomic force microscopic patterns demonstrated a decrease in the average roughness of samples' surface from 21.85 nm for plain polysulfone membrane to 5.02 nm for ones containing 2 weight percentages of graphene oxide as the optimum sample. Finally, a significant enhancement for the selectivity of carbon dioxide/methane with the value of 38.08 has been observed by the sample which was approximately 22‐fold more than that of plain polysulfone. [ABSTRACT FROM AUTHOR]

In this work, a series of fluorine‐functionalized polysulfone (F‐PSU) copolymers with intrinsic low dielectric constants (low ε) are reported, which are derived from the polycondensation reaction of 4,4′‐dichlorophenyl sulfone with bisphenol A and bisphenol F (BPF) compounds. The resulting F‐PSU copolymers show high glass transition temperatures (Tg) varying from 187 to 201 °C and are thermally stable up to 500 °C under an N2 atmosphere. The introduction of BPF units into the PSU copolymers imparts enhanced hydrophobic properties to the F‐PSU films with increased water contact angle values from 66.2° to 93.7°. Moreover, the dielectric constant and dielectric loss of the F‐PSU (sample V) film are as low as 2.2 and 0.003 at 1 kHz, respectively. Interestingly, the dielectric properties are relatively stable to near the glass transition temperature, which is because of the existence of BPF structures in the molecular backbone. Furthermore, the F‐PSU copolymers are soluble in common solvents and can be readily fabricated into flexible transparent films by the spin casting method. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The membrane technology has received considerable attention for olefin/paraffin separation in recent years, owing to its attractive energy efficiency. In this study, reduced graphene oxide (rGO) is prepared via hydrothermal treatment of graphene oxide. The prepared rGO is characterized and then incorporated into polysulfone (PSF) to fabricate mixed‐matrix membranes (MMMs). The fabricated membranes are characterized using Fourier transform infrared spectrometry, field emission scanning electron microscopy, and X‐ray powder diffraction. The gas transport properties of the MMMs are evaluated for ethylene/ethane and propylene/propane gas pairs at 2 bar and 30∘C. Permeation tests indicate that the PSF membrane embedded with 1.0 wt% of the rGO nanosheets has 143% and 193% higher C2H4 and C3H6 permeabilities, respectively, its C3H6/C3H8 selectivity is 18% higher, but its C2H4/C2H6 selectivity is 23% lower, compared to those of the pristine PSF membrane. The gas permeability enhancement is attributed to improved gas diffusion and solubility coefficients. These results indicate the potential of rGO nanosheets for the enhancement of olefin permeabilities without significant drops in olefin/paraffin selectivities. [ABSTRACT FROM AUTHOR]

In order to develop an effective and environment‐friendly method for selective adsorption of Li+, a recyclable polysulfone surface graft 4'‐aminobenzo‐12‐crown‐4‐ether (PSf‐sg‐AB12 C4) membrane was prepared via non‐solvent induced phase separation method and in situ surface grafting through nucleophilic substitution. The surface chemical compositions and the morphologies of the PSf‐sg‐AB12 C4 were systematically verified by X‐ray photoelectron spectra (XPS) and scanning electron microscopy (SEM). The dynamic adsorption process of PSf‐sg‐AB12 C4 for Li+ was well described by the pseudo‐second‐order kinetics model, and the maximum equilibrium adsorption capability was 51.99 mg⋅g‐1. Moreover, the PSf‐sg‐AB12 C4 membrane displayed good selectivity for Li+, meanwhile the selective separation factors (α) of Li+ to K+, Na+, Ca2+ and Mg2+ were 38.43, 33.13, 27.11 and 3.42, respectively. These selective adsorption results were verified by the density functional theory (DFT) calculations. Additionally, the regenerated adsorption amount of the PSf‐sg‐AB12 C4 toward Li+ after 10 cycles of adsorption/desorption was 90.37% of initial adsorption cycle. [ABSTRACT FROM AUTHOR]

In order to develop an effective and environment‐friendly method for selective adsorption of Li+, a recyclable polysulfone surface graft 4'‐aminobenzo‐12‐crown‐4‐ether (PSf‐sg‐AB12 C4) membrane was prepared via non‐solvent induced phase separation method and in situ surface grafting through nucleophilic substitution. The surface chemical compositions and the morphologies of the PSf‐sg‐AB12 C4 were systematically verified by X‐ray photoelectron spectra (XPS) and scanning electron microscopy (SEM). The dynamic adsorption process of PSf‐sg‐AB12 C4 for Li+ was well described by the pseudo‐second‐order kinetics model, and the maximum equilibrium adsorption capability was 51.99 mg⋅g‐1. Moreover, the PSf‐sg‐AB12 C4 membrane displayed good selectivity for Li+, meanwhile the selective separation factors (α) of Li+ to K+, Na+, Ca2+ and Mg2+ were 38.43, 33.13, 27.11 and 3.42, respectively. These selective adsorption results were verified by the density functional theory (DFT) calculations. Additionally, the regenerated adsorption amount of the PSf‐sg‐AB12 C4 toward Li+ after 10 cycles of adsorption/desorption was 90.37% of initial adsorption cycle. [ABSTRACT FROM AUTHOR]

The separations of ethylene/ethane and propylene/propane using polysulfone‐silica nanocomposite membranes were studied. Silica nanoparticles were prepared via sol‐gel method and the membranes by phase inversion. Characterization by Fourier transform spectroscopy and scanning electron microscopy indicated a good distribution of silica nanoparticles in the polymer matrix and also a good compatibility between the two phases. The performances of the prepared membranes in ethylene‐ethane and propylene‐propane separation were evaluated. The results showed the increments in gas permeability and selectivity by silica. Higher silica contents increased the solubility coefficient and reduced the diffusion coefficient of gases. The plasticization pressure of polysulfone was increased by incorporating the silica nanoparticles in polymer. [ABSTRACT FROM AUTHOR]

Polysulfone (PSU) is a popular material in microfiltration applications. In this study, the preparation of PSU membranes via electrospinning technology was investigated and optimized. Solutions with three different concentrations (15, 20 and 25 wt%) of PSU in dimethylformamide were electrospun at three different feed rates (1.5, 2.5 and 3.5 mL h−1) and voltages (12.5, 15 and 18 kV). The morphologies of the samples were studied using SEM. The results showed that the samples prepared from a 15 wt% solution concentration have beads‐on‐string morphologies. As the solution concentration is increased to 20 and 25 wt%, the beads disappear and uniform fibers with average diameters ranging from 0.876 to 2.078 μm depending on the voltage and the feed rate are obtained. The optimum electrospinning conditions for the highest wettability with minimum operating pressure were predicted to be a solution concentration of 25 wt%, a feed rate of 3.5 mL h−1 and a voltage of 18 kV. The prediction was verified by contact angle test measurements and filtration experiments. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Membrane technology has emerged as a viable method for water purification due to the high quality of water that is produced. Flat sheet polysulfone membranes were prepared using the phase inversion method. N‐methylpyrrolidone was used as a solvent and water as a coagulant. Lantana camara of different dosages was used as the polymeric additives in the casting solution. The morphology of the prepared membranes was analyzed using scanning electron microscopy and performance of membranes was evaluated in terms of porosity, tensile strength, elongation at break, thermal stability and surface roughness. Results shows that L. camara particles are a pore former and they have the ability to improve the antifouling properties of the resultant membrane from 1.91×105 m−1 to 0.59×105 m−1. The combination of L. camara and PSf membrane results into a PSf/LC membrane. This membrane has better antifouling properties, has improve porosity, has improved thermal properties, has a rough surface and has improved water permeability. [ABSTRACT FROM AUTHOR]

Blood‐membrane interactions can have a large impact on the performance of hemodialysis membranes, particularly for high flux membranes in which the membrane itself provides very low resistance to solute transport. The objective of this study was to examine the effects of exposure to serum on the solute clearance and convective sieving characteristics of high flux polysulfone (Optiflux F250NR), polyethersulfone (ELISIO‐25H), and asymmetric cellulose triacetate (SOLACEA‐25H) hemodialyzers using both vitamin B12 and a range of polydisperse dextrans. Zeta potential measurements were used to obtain additional insights into the changes in membrane surface properties. Exposure to serum in a simulated dialysis session caused a significant reduction in both solute clearance and sieving coefficients for the polysulfone/polyethersulfone dialyzers, particularly for the larger molecular weight solutes. In contrast, the transport characteristics of the asymmetric cellulose triacetate dialyzers were almost unchanged after exposure to serum. The zeta potential of the cellulose triacetate membrane became slightly more negative after exposure to serum, consistent with an adsorbed protein layer composed largely of albumin. The net result is that the asymmetric cellulose triacetate dialyzer had dramatically higher clearance of the larger dextrans after exposure to serum, with the clearance and sieving coefficient for a 10 kDa molecular weight dextran being more than an order of magnitude greater than that of the polysulfone/polyethersulfone membranes. These results provide important insights into the expected clinical performance of these high flux dialyzers. [ABSTRACT FROM AUTHOR]

ABSTRACT: Polymers containing CO2‐philic groups are of great interest for CO2/light gas separation membranes because the affinity toward CO2 can effectively increase CO2 solubility and thus permeability. In this study, polysulfones (PSUs) modified with different degrees of benzyldimethylamine (DMA), benzyltrimethylammonium fluoride (TMAF), and benzyltrimethylammonium iodide (TMAI) were synthesized using sequential post‐functionalization reactions and investigated for CO2/N2 and CO2/CH4 separation. The physical properties of these polymers were studied, including density, fractional free volume, and glass transition temperature. In contrast to the conventional wisdom that tertiary amines exhibit an affinity toward CO2, this study convincingly shows that the DMA substituent has a minimal impact on CO2 solubility and CO2/light gas solubility selectivity in PSUs under dry condition. On the other hand, incorporating TMAF and TMAI in PSU significantly increases CO2 solubility. Particularly, introducing TMAI with a molar ratio of 1.07 relative to PSU repeating units increases CO2/CH4 solubility from 4.4 to 5.2, CO2/CH4 permeability selectivity from 21 to 45, and CO2/N2 permeability selectivity from 24 to 33 at 35 °C, while the CO2 permeability decreases from 5.6 to 1.7 Barrers. The effect of these functional groups in PSUs on gas diffusivity and diffusivity selectivity can be satisfactorily described by the free volume model. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018, 56, 1239–1250 [ABSTRACT FROM AUTHOR]

ABSTRACT: Polymeric nanospheres with uniform sizes, functional surfaces, and high mechanical strength and thermostability are attracting wide interest in different applications. Here, a new kind of polysulfone micellar spheres with PEGylated surfaces is prepared via directly heating the solution of an amphiphilic block copolymer, polysulfone‐b‐polyethylene glycol (PSF‐b‐PEG). The sizes of the micelles are uniform and tunable between ∼42 and ∼443 nm. TEM characterizations show that the micelles are core‐shell structures with PEG as the corona and PSF as the core. PEG endows the micelles with dispersibility in water and good biocompatibility, while PSF provides the mechanical strength and thermostability. The effects of PEG contents, polymer solution concentrations, solvent types, and heating temperatures are systematically investigated. Furthermore, heat resistance tests show that the micelles are stable at 150–180 °C. These PSF‐b‐PEG micellar spheres are expected to be applied in demanding environmental conditions such as heating involved surface modification process. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018, 56, 769–777 [ABSTRACT FROM AUTHOR]

Incorporation of facilitating agents is one of the promising strategies being researched in recent years to cross the Robeson bounds for gas separations using polymeric membranes. The ways in which such inclusions modify the performance of membranes are not always clear. Here, we study the performance of two glassy membranes, Polyfurfuryl alcohol and Polysulfone, in O2/N2 and CO2/N2 separations, with Cobalt phthalocyanine in insoluble and solubilized forms as the facilitating agent. The results show that in general, three effects are important: (1) a barrier effect, (2) a facilitation effect, and (3) morphological effects on the polymer matrix due to an incompatibility between the particles and the polymer. These results provide some insight into the action of facilitating agents in soluble and insoluble form, when used as membrane additives. © 2017 American Institute of Chemical Engineers AIChE J, 63: 186-199, 2018 [ABSTRACT FROM AUTHOR]

ABSTRACT Solution blow spinning, SBS, was used to prepare fibrous films of thermoplastic nanocomposites with potential antibacterial properties based on polysulfone, PSF, filled with well dispersed TiO2 nanoparticles. The PSF/TiO2 nanocomposites were produced with different nanoparticles content up to 10% by weight. A wide characterization was carried out focusing on the morphology at the nanoscale, roughness, contact angles, and surface free energy. Cell adhesion was studied by inspection by scanning electron microscopy (SEM). A uniform dispersion of the nanofiller was achieved, with the nanoparticles evenly embedded in the polymer along the fibers when they were created during the blow spinning process. TiO2 content influenced the topography of the films, most likely due to a direct effect on the solvent evaporation rate. The results obtained pointed out that an increase of the surface hydrophobicity as a result of the increased roughness induced by the presence of TiO2 nanoparticles was the main contribution to the reduction of DH5α Escherichia coli cells adhesion. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 1575-1584 [ABSTRACT FROM AUTHOR]

ABSTRACT A series of DABCO-functionalized polysulfones were synthesized and characterized. The effect that crosslinking has on the membrane properties containing different degrees of functionalization was evaluated. These polymers showed good thermal stability below the fuel cell operation temperature, T < 100 °C, reflected by the TOD, TFD, and thermal durability. The water uptake increased as the percentage of DABCO groups increased and the crosslinked membranes showed lower capacity to absorb water than the non-crosslinked ones favoring thus the dimensional stability of the first ones. Membranes in the chloride form containing low degree of functionalization exhibited the highest tensile strength values. The ionic conductivity of non-crosslinked membranes varied as a function of the functionalization degree until a value of around 100% achieving a maximum value at 86%. However, the crosslinked ones showed satisfactory ionic conductivities for values higher than 100%. The behavior of these polymeric materials in alkaline solutions revealed a great alkaline stability necessary to be used as solid electrolytes in fuel cells. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 1326-1336 [ABSTRACT FROM AUTHOR]

In this work, a sustainable, in situ UV-induced reactive electrospinning technique is demonstrated to produce solvent stable electrospun membranes in a single operation. This approach is based on the addition of an acrylated cross-linker into the polysulfone-based dope solution and on the online irradiation of the solution while it is electrospun, thus allowing reaction during formation of the fibers. The electrospinning parameters and UV curing conditions are thoroughly optimized. Mats are also prepared via an offline approach in which UV curing is performed on the previously electrospun mats and compared with the membranes fabricated via the online curing method. As opposed to pristine polysulfone fibers, the electrospun mats containing acrylate are stable in a variety of solvents, such as tetrahydrofurane (THF), acetone, ethyl acetate, dimethylsulfoxide (DMSO), and toluene. The online irradiated mats of desired thickness are produced in a single step operation and the sustainability of the process is achieved through the optimization of electrospinning and solution parameters. [ABSTRACT FROM AUTHOR]

Using molecular design and polymer reactions, two types of bidentate Schiff base ligands, salicylaldehyde-aniline (SAN) and salicylaldehyde-cyclohexylamine (SCA), were synchronously synthesized and bonded onto the side chain of polysulfone (PSF), giving two bidentate Schiff base ligand-functionalized PSFs, PSF-SAN and PSF-SCA, referred to as macromolecular ligands. Following coordination reactions between the macromolecular ligands and Eu(III) and Tb(III) ions (the reaction occurred between the bonded ligands SAN or SCA and the lanthanide ion), two series of luminescent polymer-rare earth complexes, PSF-SAN-Eu(III) and PSF-SCA-Tb(III), were obtained. The two macromolecular ligands were fully characterized by Fourier transform infrared (FTIR), 1H NMR and UV absorption spectroscopy, and the prepared complexes were also characterized by FTIR, UV absorption spectroscopy and thermo-gravity analysis. On this basis, the photoluminescence properties of these complexes and the relationships between their structure and luminescence were investigated in depth. The results show that the bonded bidentate Schiff base ligands, SAN and SCA, can effectively sensitize the fluorescence emission of Eu(III) and Tb(III) ions, respectively. PSF-SAN-Eu(III) series complexes, namely the binary complex PSF-(SAN)3-Eu(III) and the ternary complex PSF-(SAN)3-Eu(III)-(Phen)1 (Phen is the small-molecule ligand 1,10-phenanthroline), produce strong red luminescence, suggesting that the triplet state energy level of SAN is lower and well matched with the resonant energy level of the Eu(III) ion. By contrast, PSF-SAN-Eu(III) series complexes, namely the binary complex PSF-(SCA)3-Tb(III) and the ternary complex PSF-(SCA)3-Tb(III)-(Phen)1, display strong green luminescence, suggesting that the triplet state energy level of SCA is higher and is well matched with the resonant energy level of Tb(III). [ABSTRACT FROM AUTHOR]

Polysulfone (PSF) was grafted chemically with polyethylene glycol (PEG) of different molecular weights (400, 2000, 10 000, and 20 000) and heparin to prepare PSF-PEG-Hep membranes (labeled as PSF-PEG400-Hep, PSF-PEG2000-Hep, PSF-PEG10 000-Hep, and PSF-PEG20 000-Hep). These membranes were synthesized via the following steps: (i) PSF chloromethylation; (ii) PEGylation; and (iii) heparin immobilization process. Water contact angle, critical water permeation pressure, ATR-FTIR, 1H NMR, UV-visible spectrophotometry, and X-ray photoelectron spectroscopy were conducted to prove grafting success and to fix the optimal reaction parameters during chemical modification processes. To further evaluate the application potential of the PSF-PEG-Hep membrane in a membrane oxygenator, we conducted pure CO2 and O2 gas permeation tests and measured the gas exchange rates of CO2 and O2 through a membrane oxygenator using fresh porcine blood. Meanwhile, the hemocompatibility of the membrane was analyzed and compared by protein adsorption, platelet adhesion, and blood coagulation tests. Results of pure gas permeation experiments indicated that the excellent gas transmission properties through PSF membrane were preserved after modification. Blood oxygenation experiments through the PSF-PEG10 000-Hep membrane showed that when the flow rate of porcine blood was 1.5 L/min, CO2 and O2 exchange rates reached 102 and 110 mL/min, respectively, which could basically satisfy the gas exchange potential of commercial membrane oxygenators. Besides, the PSF-PEG-Hep membrane has demonstrated more prominent blood compatibility than PSF. [ABSTRACT FROM AUTHOR]

A series of aliphatic polysulfones is synthesized via ADMET polymerization in which a sulfone group is located precisely after every 8th, 14th, and 20th carbon. Primary structural characterization is accomplished using 1H NMR, 13C NMR, and IR. Polymer morphology is studied by DSC and X-ray scattering, which reveals layered morphologies comprised of polyethylene crystallites along with sulfone groups arranged in sheets. In contrast to other precision polymers with functional groups synthesized by ADMET, this morphology is found at all spacer lengths. Prior to hydrogenation the sulfone polymers show Tm decreasing with increasing sulfone concentration, a typical phenomenon attributed to the mix of cis and trans configurations producing defects in the crystals. However, following hydrogenation, the melting temperature increases as the sulfone group concentration increased rather than decreased, with the highest Tm being 175 °C. This is an increase of 45 °C relative to linear polyethylene synthesized via ADMET chemistry. The precise location of the sulfone groups, which are not tactic, within these polyethylenes increases crystallinity, promotes secondary bonding and increases Tm. [ABSTRACT FROM AUTHOR]

ABSTRACT A facile, efficient approach for preparation of functionalized aromatic polysulfones by postpolymerization modification with thiol-ene click chemistry is described. The key synthetic strategy is to incorporate a pendant vinyl ether group into polysulfones as a reactive precursor with controlled degrees of functionalization. Synthetic utility of the pendant alkenyl group is demonstrated by generating diverse polymer derivatives using thiol-ene functionalization including glycosylated polysulfone. The highly reactive alkene platform in the polymer affords convenient, metal-free, and azide-free click transformations to create diverse ranges of new functionalized polysulfones that could be applied in various applications. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 3237-3243 [ABSTRACT FROM AUTHOR]

Symmetrically disubstituted 1,1-diphenylethylene derivatives, 1,1-bis[4-( t-butyldimethylsiloxy)phenyl]ethylene and 1,1-bis(4-hydroxyphenyl)ethylene, were prepared by new synthesis methods and employed as functionalized monomers in the preparation of new poly(ether ether sulfone) derivatives, with the introduction of the 1,1-diphenylethylene unit along the polymer backbone. A series of parent 1,1-diphenylethylene based poly(ether ether sulfone)s were prepared via (a) the cesium fluoride catalysed polycondensation reactions of dihalogenated diaryl sulfones with silylated bisphenols and (b) the base catalysed aromatic nucleophilic substitution polycondensation reaction between aromatic dihalogenated diaryl sulfones with bisphenols. The post-polymerization sulfonation reaction via the thiol-ene addition reaction of the poly(ether ether sulfone) precursor containing the 1,1-diphenylethylene unit along the backbone, with sodium 3-mercapto-1-propane sulfonate, afforded well-defined sulfonated poly(ether ether sulfone), with the alkyl sulfonate group introduced pendant to the polymer backbone. The organic compounds and different polymer derivatives were characterized by standard chromatography, spectroscopy, spectrometry, thermal analyses, microscopy and X-ray diffraction measurements. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Ever since the discovery of graphene, its potential has been predicted for a number of applications in various fields such as electronics, sensors, environmental decontamination techniques, separations and biomedicine to name a few. Among various such fields, the research in graphene-based nanocomposites membranes is still in its infancy as there is not a significant research published in this field so far. However, interestingly this field is registering an exponentially upward trend recently. This review article provides a brief description of polymer nanocomposite membranes with graphene as one of the most indispensable components in the membranes. In this article, we describe in a systematic and comprehensive manner the most recent research published so far in the nanocomposite membranes with graphene and the most commonly used polymers namely the polysulfone and the cellulose derivatives. This article also describes the main applications of these polymeric membranes in the fuel cells and in water purification processes containing the current literature data as well as the authors' own research. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT The thermomechanical properties of anion exchange polymers based on polysulfone (PSU) quaternized with trimethylamine (TMA) or 1,4-diazabicyclo[2.2.2]octane (DABCO) and containing hydroxide or chloride anions by tensile stress-strain tests and dynamic mechanical analysis (DMA) have been determined. The reported mechanical properties included the Young's modulus, tensile strength, and elongation at break from tensile tests and the storage and loss modulus and glass transition temperature from DMA. The anion exchange membranes behaved as stiff polymers with Young's modulus in the order of 1 GPa, relatively with high strength (about 30 MPa) and low elongation at break (around 10%) was observed. Tensile tests were also made with membranes exchanged with hydrogen-carbonate and carbonate anions to control the absence of important carbonation of the OH form. The glass transition temperatures were of the order of 150 °C (PSU-TMA) or 200 °C (PSU-DABCO) for the hydroxide form, confirmed by differential scanning calorimetry; they increase further by about 50 K, when hydroxide ions are replaced by chloride. This result and the increase of the storage modulus could be interpreted by the higher hydration of hydroxide ions and the plasticizing effect of water, which reduced the Van der Waals interactions between the macromolecular chains. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016, 54, 1180-1187 [ABSTRACT FROM AUTHOR]

Porous polymeric membranes are used in numerous applications including water filtration systems. Fouling from proteins, toxins, bacteria, and cells present in the water limits membrane utility. Surface modification techniques that retain desired bulk properties while decreasing fouling can effectively extend membrane lifetime. Herein, water vapor plasmas are utilized to create hydrophilic polysulfone ultrafiltration membranes. The permanency of the treatment over two months correlates to covalent incorporation of hydrophilic functional groups into the polymer backbone. Modified membranes show enhanced hydrodynamic characteristics and do not require preconditioning. Thus, water vapor plasma modification provides a potential route to extend ultrafiltration membrane lifetime. [ABSTRACT FROM AUTHOR]