Micro‐ and ultrafiltration film membranes from poly(ether ether ketone) (PEEK)

Film membranes from the thermoplastic poly(ether ether ketone) (PEEK) have been extruded and tested for their microfiltration and ultrafiltration performance. High‐performance asymmetric membranes have been obtained by extruding polymer blends of PEEK, polysulphone, and a small molecule solvent mixture, and then by removing the polysulphone and solvent in a subsequent extraction step. The process for making ultrafiltration membranes differs from microfiltration membranes only in the relative blend components, and the temperature of the film pick‐up rolls. Processing parameters with important effects on the membrane performance have been identified. Microfiltration membranes are characterized by their pore‐size distributions and SEM, and ultrafiltration membranes by their rejection of bovine serum albumin, bubble point, and SEM. Composite membrane for nanofiltration utilizing the PEEK ultrafiltration membrane as a substrate performed similarly to a commercial membrane for the same purpose. This work details the best method for making PEEK film membranes published to date. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 1146–1155, 1999     

Greatly improved toughness of isotactic polypropylene blends with traces of carbon nanotubes

In this work, the β‐nucleated isotactic polypropylene (iPP)/ ethylene‐octene copolymer (POE) blends demonstrated greatly enhanced impact toughness by adding traces of carbon nanotubes (CNTs) (only 0.05 wt%). When the POE content was 30 wt%, the impact strength of β‐nucleated iPP/POE blends with CNTs was as high as 51.7 kJ/m², about 5.6 kJ/m² higher than β‐nucleated iPP/POE blends, 15.2 kJ/m² higher than CNTs‐filled iPP/POE blends, and almost 19 times of pure iPP sample. This significantly improved impact toughness was considered to be attributed to the shear yielding and multiple‐crazing, originating from the presence of abundant β‐crystals in the iPP matrix, the enhanced mobility of the molecular chains in the confined amorphous region of iPP lamellae and the homogenous distribution of POE dispersed phase with a small size, indicating the synergistic effect of CNTs, β‐nucleating agent and POE on the toughness of iPP. POLYM. ENG. SCI., 59:757–764, 2019. © 2018 Society of Plastics Engineers     

Pervaporation separation of ethanol–water mixtures using ionically crosslinked blended polyacrylic acid (PAA)–nylon 6 membranes

The pervaporation separation of ethanol–water mixtures was carried out through a series of ionically crosslinked polyacrylic acid (PAA)–Nylon 6-blended membranes crosslinked to varying degrees in aluminum nitrate solution. The polyacrylic acid (PAA)–Nylon 6 membranes were cast from homogeneous PAA–Nylon 6 mixtures to various thicknesses and then crosslinked. Optimum pervaporation results were obtained from crosslinked blends containing 75 wt% Nylon 6 and 25 wt% PAA. These membranes have separation factors (water/ethanol) of 35–40 at flux rates of 120–160 g/m² h. The optimum crosslinking time was found to be approximately 35 h to yield membranes with the best separation and flux rates at 25 wt% PAA content.     

Performance of Nanofiltration Membranes for Solvent Purification in the Oil Industry

The extraction stage of edible oil in the oil industry is commonly performed by using toxic solvents (e.g. hexane) and processes with high energy consumption (e.g. distillation, evaporation) to recover the solvent, which represents around 70–75 wt% in the oil–solvent mixture. In this paper, a membrane-based extraction method using nanofiltration (NF) membranes is presented. Commercial nanofiltration membranes made of different polymers (Desal-DK-polyamide NF from GE-osmonics^®, NF30 polyethersulfone NF from Nadir^®, STARMEM^TM122 polyimide from MET^® and SOLSEP NF030306 silicone base polymer SOLESP^®) were selected and tested to recover the solvent from soybean oil/solvent (10–20–30% w/w oil) mixtures at various separation pressures and constant temperature in a dead-end filtration set up. The selection of the solvent was made in order to compare solvents obtainable from renewable resources, such as ethanol, iso-propanol and acetone, with solvents traditionally used in the industry (i.e. cyclohexane and n-hexane). The structural stability of the membranes towards the different solvents used in this work was verified visually, by the variation of the membrane area and by means of permeate flux assessments. Desal-DK and NF30 showed poor filtration performance and even visible defects after exposure to acetone but a good performance was obtained for the nanofiltration membranes STARMEM^TM122 and SOLSEP NF030306 with ethanol, iso-propanol and acetone. For example, considering a mixture with 30% edible oil in acetone, STARMEM^TM122 shows a flux and oil rejection of 16.8 L m^?2 h and 70%, respectively. For the same conditions, SOLSEP NF030306 exhibited a flux of 4.8 L m^?2 h with 78% rejection, which shows the potential application of nanofiltration membranes in the oil industry.     

Application of polyhedral oligomeric silsesquioxane to the stabilization and performance enhancement of poly(4‐methyl‐2‐pentyne) nanocomposite membranes for natural gas conditioning

The application of octatrimethylsiloxy polyhedral oligomeric silsesquioxane (POSS) nanoparticles was investigated in the fabrication of novel reverse‐selective poly(4‐methyl‐2‐pentyne) (PMP) nanocomposite membranes for the separation of heavier hydrocarbons from methane. Generally, PMP and PMP–fumed silica (FS) nanocomposite membranes suffer severe physical aging with approximately 40% permeation flux reduction over 120 days. A straightforward strategy was introduced to suppress the physical aging of PMP and also to improve the thermal stability without compromising the selectivities and permeabilities through the incorporation of a functionalized POSS–FS binary filler system. Fourier transform infrared spectroscopy and scanning electron microscopy proved productive interactions between the fillers and polymer, with a fair compatibility between them. Thermogravimetric analysis confirmed that the thermal stability of the neat PMP was enhanced by the incorporation of the fillers into the nanocomposites. The addition of POSS and FS led to improved operational performance, such as in the permeability and selectivity, over the neat PMP. The permeation stabilities of the PMP–POSS and PMP–FS–POSS nanocomposite membranes were clearly improved over a long time (120 days). The permeation data indicated that the PMP–3 wt % POSS–20 wt % FS nanocomposite membrane is promising for C₃H₈/N₂ and C₃H₈/CH₄ separation. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45158.     

Effect of phase composition of natural quartz raw material on characterization of microfiltration ceramic membranes

The results of development of multi-layer ceramic membranes on the basis of natural quartz raw material from Mongolia are presented. The influence of the phase composition and temperature of calcination on the porosity, morphology and mechanical strength of large-porous ceramic support obtained by the method of isostatic pressing was studied. It was established that multi-layer ceramic membranes obtained by the application of water suspension of high-disperse quartz sand of Mongolia and alumosilicate binder with the addition of 15–35 wt% of quartz are characterized by optimal properties. The developed tubular ceramic membranes with the average pore size 5.3 µm, coefficient of air permeability (4.17–4.41)×10⁻¹³ m², productivity by water 46.3–48.0 m³/(h×m²×bar) and mechanical strength 2.27–2.53 MPa are perspective for wide use in microfiltration processes.     

Curing of epoxy resin with poly(m‐phenylene methylphosphonate)

The mechanism and kinetics of curing of epoxy resin with poly(m‐phenylene methylphosphonate) (PMP) was studied by extraction and swelling experiments, DSC, ³¹P NMR, and FTIR. It was shown that at linear heating of 20°C/min PMP cures bisphenol A type epoxy resin at 230–300°C, whereas in the presence of catalytic amount of 2‐methyl imidazole the curing occurs at 200–230°C. Under isothermal conditions, epoxy resin was cured with PMP after 40–70 min at 150°C. An unusual mechanism of curing due to opening and insertion of epoxy into the phosphonate bond was suggested. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 4011–4022, 2006     

Preparation and characterization of a novel hydrophilic PVDF/PVA UF membrane modified by carboxylated multiwalled carbon nanotubes

Polyvinylidene fluoride (PVDF)/polyvinyl alcohol (PVA) ultrafiltration (UF) membranes were prepared via a phase inversion method employing the modification of carboxylated multiwalled carbon nanotubes (MWCNTs‐COOH). Various contents of MWCNTs‐COOHs (0.00–0.15 wt%, weight of casting solution) were added into PVDF/PVA/dimethyl sulfoxide systems for the fabrication of the plate UF membrane. Fourier transform infrared spectroscopy spectra identified the successful introduction of carboxyl through the C?O peak at 1730 cm^?1. Scanning electron microscopy images exhibited the external surface and the asymmetric morphology with the appearance of a sponge‐like inner structure. Atomic force microscopy analysis determined the roughness values and rougher topography. The hydrophilicity of the composite membrane containing 0.09 wt% of MWCNTs‐COOHs improved the most. This sample has the highest pure water flux, approximately doubled (126.6 L·m^?2·h^?1) compared to the PVDF/PVA membrane (68.6 L·m^?2·h^?1), an enhanced bovine serum albumin flux recovery rate, showing an increase of 17%, and the best fouling resistance ability. Meanwhile, the porosity and dynamic contactangle also indicate the enhancement of membrane hydrophilicity. Dextran (DEX) 600k rejection reached 91.0%. Break strength, elongation at break, and Young's modulus also had improvements of 60%, 215.5%, and 56.7%, respectively, when the MWCNTs‐COOH content was 0.12 wt%. POLYM. ENG. SCI., 56:955–967, 2016. © 2016 Society of Plastics Engineers     

Investigation of electrospun and film‐cast PVC membranes incorporated with aliquat 336 for efficient Cd extraction: A comparative study

This article was aimed to investigate the cadmium extraction behaviors of the two different polyvinyl chloride membranes incorporating Aliquat 336—electrospinning and film‐casting. An optimal investigation condition for membranes used in the extraction process was produced at 25 kV with 10 cm tip‐to‐collector distance. Membranes were electrospun for 8 h at 200 μL/h. Membrane extraction studies were carried out using a 127 mg/L Cd(II) solution. Scanning electron microscope (SEM) images revealed differences in fiber diameters and membrane morphology. The addition of Aliquat produced very fine fibers (7–722 nm) resulting Brunauer‐Emmett‐Teller (BET) surface areas of 4.67–11.3 m²/g for electrospun membranes and 1.70–5.44 m²/g for film‐casted membranes. Extraction studies using membranes with different levels of Aliquat (0–40% w/w) revealed that the cadmium extraction performance of electrospun membranes was significantly better than conventional film‐cast membranes. For 40% Aliquat 336, with an initial concentration of 127 mg/L Cd, the cast membrane extracted down to concentration to 115 mg/L as compared to electrospun membrane, which extracted down to 88 mg/L within 40 h. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Polyamide/Polystyrene Blend Compatibilisation by Montmorillonite Nanoclay and its Effect on Macroporosity of Gas Diffusion Layers for Proton Exchange Membrane Fuel Cells

This work deals with a new route to modify polymer blend morphology in order to improve the porosity of gas diffusion layers (GDLs) for proton exchange membrane fuel cells (PEMFCs). First, electrically conductive polymer‐based blends were carefully formulated using a twin‐screw extrusion process. Blend electrical conductivity was ensured by the addition of high specific surface area carbon black and synthetic graphite flakes. Final GDL porosity, in particular its macroporosity, was generated by melt blending polyamide 11 (PA11) matrix with polystyrene (PS) followed by PS extraction with tetrahydrofuran (THF) solvent at room temperature. In order to improve GDL porosity by the optimisation of PS dispersion in the PA11 matrix, PA11/PS blends were compatibilised by the addition of 2 wt.‐% of clay. It was observed that both macroporosity and pore size distribution were beneficially modified after blend compatibilisation. Final GDL conductivity of about 1.25 S cm^–1, a porosity of 53% and a specific pore surface area of 75 m² g^–1 were achieved.     

Novel block ionomers. III. Mechanical and rheological properties

Select rheological (dynamic viscoelastic) and mechanical properties of novel block cationomers and anionomers and their blends have been investigated. The block ionomers were linear di‐ and triblocks, and symmetric three‐arm stars comprising hydrophobic polyisobutylene (PIB) blocks attached to ionized poly(methacrylic acid) (PMAA^?X⁺, where X⁺ = Na⁺, Zn²⁺) and poly[2‐(dimethylamino)ethyl methacrylate] (PDMAEMA⁺I^?) blocks. The specific structures investigated were the well‐defined diblocks PIB‐b‐PMAA^? and PIB‐b‐PDMAEMA⁺ and their blends, the triblocks PMAA^?‐b‐PIB‐b‐PMAA^? and PDMAEMA⁺‐b‐PIB‐b‐PDMAEMA⁺ and their blends, and the three‐arm star anionomer Φ(PIB‐b‐PMAA^?)₃. For comparison, the properties of the precursor PIBs and unionized blocks have also been studied. Hydrogen bonding between the carboxyl groups of the PMAA blocks in PIB‐b‐PMAA diblocks leads to inverse micelles. Neutralization of the PMAA by Zn(AcO)₂ and quaternization of the PDMAEMA segments by CH₃I in the triblock copolymers and star copolymers yielded ionic domains, which self‐assemble and produce physical networks held together by coulumbic interaction. The physical/chemical characteristics of the domains control the viscoelastic behavior and mechanical properties of these block ionomers. The mechanical properties of the various block ionomers were significantly enhanced relative to the precursors, and they were thermally stable below the transition temperature. Further, the thermomechanical properties of these novel materials were satisfactory even above 200°C. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1516–1525, 2003     

Polyvinyl alcohol‐polyethylene oxide‐carboxymethyl cellulose membranes for drug delivery

The purpose of this research was to develop blends of poly(vinyl alcohol) (PVA)‐poly(ethylene oxide) (PEO) and carboxymethyl cellulose (CMC) by two approaches: solvent casting and freeze‐drying to develop membranes for various biomedical applications. The PVA/PEO/CMC blends in different compositions of 90/10/20, 80/20/20, 70/30/20, 60/40/20, and 50/50/20 were prepared and were coated on polyester (PET) nonwoven fabric and were subsequently freeze‐dried (FD). The influence of PEO concentration on the blend membranes was investigated and characterized by X‐ray diffraction (XRD), differential scanning calorimetry, and attenuated total reflectance‐fourier transform infra‐red (ATR–FTIR) techniques. The water vapor transmission rate (WVTR), swelling behavior, and surface morphology of the FD membranes was also investigated. It was observed that an increase of PEO concentration in blends makes the membranes more fragile. However, the coating of this blend on PET fabric helps in developing the stable membrane. Swelling of the membranes decreased with the increase in the PEO concentration. XRD showed decrease in crystallinity with increase in concentration of PEO. Morphological studies showed a highly porous structure with interconnected pores. The total porosity of the membranes was found to be in the range 89–92%. The FD membranes were found to have WVTR in the range 2000–3000 g/m²/day. A model drug, ciprofloxacin hydrochloride was also incorporated in the matrix and drug release was studied. The antimicrobial nature of the membranes was monitored against E. coli by zone of inhibition method. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Synthesis and in situ functionalization of microfiltration membranes via high internal phase emulsion templating

The continuous phase of high internal phase emulsions (HIPEs) can be polymerized to produce highly porous materials, known as polyHIPEs. The aim of this work was to synthesize polyHIPE microfiltration membranes having a hydrophobic bulk and a hydrophilic surface to enhance their performance. Therefore, in situ functionalization was performed through interfacial copolymerization of a hydrophobic monomer (butyl acrylate) in the continuous phase with a hydrophilic monomer (sodium acrylate) in the disperse phase. The functionalization of polyHIPEs was studied by using conductometric titration and Fourier transform IR spectroscopy. We show that the surface charge density of poly(butyl acrylate)‐based polyHIPEs can be controlled by varying the concentration of sodium acrylate in the disperse phase. PolyHIPE microfiltration membranes have higher intrinsic permeability (around 1.31 × 10^?8 m²) in comparison to conventional microfiltration membranes. The interfacial copolymerization of sodium acrylate increases the permeability of microfiltration membranes. In addition, the rejection of polyHIPE microfiltration membranes was studied for the separation of microalgae. © 2019 Society of Chemical Industry     

Toughening effects of ethylene–vinyl acetate copolymers with different vinyl acetate content and viscosity on nylon 1010 blends

Nylon 1010 blends with ethylene–vinyl acetate copolymer (EVA) and maleated ethylene–vinyl acetate (EVA‐g‐MAH) were prepared through melt blending. The vinyl acetate (VA) content and viscosity of EVA significantly affected the notched impact strength of nylon/EVA/EVA‐g‐MAH (80/15/5) blends. The nylon/EVA/EVA‐g‐MAH blends with high notched impact strength (over 60 kJ/m²) were obtained when the VA content in EVA ranged from 28 to 60 wt%. The effect of VA content on the notched impact strength of blends was related to the glass transition temperature for EVA with high VA content and crystallinity for EVA with low VA content. For nylon blends with EVA with the same VA content, low viscosity of EVA led to high notched impact strength. Fracture morphology of nylon/EVA/EVA‐g‐MAH (80/15/5) blends showed that blends with ductile fracture behavior usually had large matrix plastic deformation, which was the main energy dissipation mechanism. A relationship between the notched impact strength and the morphology of nylon/EVA/EVA‐g‐MAH (80/15/5) blends was well correlated by the interparticle distance model. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers     

Novel polyisobutylene stars. XXIII. Thermal,mechanical, and processing characteristics of poly(phenylene ether)/polydivinylbenzene(polyisobutylene‐b‐polystyrene)37 blends

The objective of these investigations was to increase the use temperature of novel star‐block polymers consisting of a crosslinked polydivinylbenzene (PDVB) core from which radiate multiple poly(isobutylene‐b‐polystyrene) (PIB‐b‐PSt) arms, abbreviated by PDVB(PIB‐b‐PSt)_n. We achieved this objective by blending star‐blocks with poly(phenylene oxide) (PPO) that is miscible with PSt. Thus, various PPO/PDVB(PIB‐b‐PSt)_n blends were prepared, and their thermal, mechanical, and processing properties were investigated. The hard‐phase glass‐transition temperature of the blends could be controlled by the amount (wt %) of PPO. The blends displayed superior retention of tensile strengths at high temperatures as compared to star blocks. The melt viscosities of blends with low weight percentages of PPO were lower than those of star blocks. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2866–2872, 2002     

Reactive compatibilization of high‐impact poly(lactic acid)/ethylene copolymer blends catalyzed by N,N‐dimethylstearylamine

The inherent brittleness of poly(lactic acid) (PLA) limits its wide application in many fields. Here, high‐impact PLA/ethylene–methyl acrylate–glycidyl methacrylate random terpolymer (EMA–GMA) blends were prepared with the addition of a small amount of N,N‐dimethylstearylamine (DMSA) catalyst. It was found that the notched impact resistance of various PLA/EMA–GMA blends could be considerably improved by adding DMSA. In particular, the notched Izod impact strength of the blend with 20 wt% EMA–GMA increased from 35.6 to 83.5 kJ m^?2 by adding 0.2 wt% DMSA. Reactive compatibilization between PLA and EMA–GMA with DMSA was studied using Fourier transform infrared spectroscopy. The results indicated that DMSA promoted the reaction between the epoxide group of EMA–GMA and end groups (–OH, –COOH) of PLA. This considerably improved the interfacial adhesion, leading to better wetting of the dispersed phase by the PLA matrix and finer dispersed EMA–GMA particles. Therefore, the significant increase in notched impact strength was attributed to the effective reactive compatibilization promoted by DMSA. © 2013 Society of Chemical Industry     

Optimization of structure and properties of polyphenylene sulfide porous membrane by controlling the process of thermally induced phase separation

Polyphenylene sulfide (PPS) porous membranes were successfully prepared from miscible blends of PPS and polyethersulfone (PES) via thermally induced phase separation followed by subsequent extraction of the PES diluent. The morphologies, crystalline structures, mechanical properties, pore structures and permeate fluxes of the PPS porous membranes obtained from different phase separation processes were characterized and are discussed. During the phase separation in the heating process, PPS and PES mainly underwent liquid–liquid phase separation, and then a nonhomogeneous porous structure with a mean pore size of 100 μm and a honeycomb‐like internal structure formed on the membrane surface. The phase separation of PPS/PES occurring in the cooling process was easier to control and the related pore diameter distribution was more regular. In the process of direct annealing, as the phase separation temperature decreased, the pore size distribution became more homogeneous and the mean diameter of the pores also decreased gradually. When the phase separation temperature decreased to 200 °C, PPS membranes with a network structure and a uniform as well as well‐interconnected porous structure could be obtained. In addition, the maximum permeation flux reached 1718.03 L m^–2 h^–1 when the phase separation temperature was 230 °C. The most probable pore diameter was 6.665 nm, and the permeate flux of this membrane was 2.00 L m^–2 h^–1; its tensile strength was 17.07 MPa. Finally, these PPS porous membranes with controllable pore structure as well as size can be widely used in the chemical industry and energy field for liquid purification. © 2020 Society of Chemical Industry     

Poly(arylene sulfide sulfone) hybrid ultrafiltration membrane with TiO2‐g‐PAA nanoparticles: Preparation and antifouling performance

Poly(arylene sulfide sulfone) (PASS) is a kind of newly developed polymeric membrane material which has excellent mechanical strength, thermal stability, and solvent resistance. And, it would be a potential material for high temperature ultrafiltration and organic solvent filtration. In this article, PASS hybrid ultrafiltration membrane with improved antifouling property was prepared by mixing TiO₂ nanoparticles which were grafted with polyacrylic acid (PAA). These membranes were prepared by a phase inversion technique and their separation performance and antifouling property of the prepared membranes were investigated in detail by SEM, FTIR, EDS, contact angle goniometry, filtration experiments of water, and BSA solution. The results shown that the TiO₂‐g‐PAA nanoparticles dispersed well in membrane matrix, the hydrophilicity of the membranes prepared within TiO₂‐g‐PAA nanoparticles have been improved and these membranes exhibited excellent water flux and antifouling performance in separation than that of the pure PASS membranes and PASS membranes with TiO₂ nanoparticles. More specifically, among membrane sample M0, M1.5, and MP1.5, MP1.5 which contained 1.5 wt% TiO₂‐g‐PAA exhibited the highest water permeation (190.4 L/m² h at 100 kPa), flux recovery ratio, and the lowest BSA adsorption amount. POLYM. ENG. SCI., 55:2829–2837, 2015. © 2015 Society of Plastics Engineers     

Production and characterization of membranes of recycled waste materials: Cellulose acetate,obtained from sugarcane bagasse with polystyrene from plastics cups

Membranes of cellulose acetate from sugarcane bagasse (CA), as well as blends of this cellulose acetate and polystyrene from plastic cups (CA/PS) were produced by casting utilizing dichloromethane as solvent at the concentration 12% w/w. The membranes were characterized regarding ion diffusion by dialysis and properties of pure water permeation rate, PEG rejection (utilizing an aqueous solution 1% w/v of polyethylene glycol (PEG), 45 and 80 kDa). Thermal characterization by thermogravimetric analysis and differential scanning calorimetry were also performed. The morphology of the membranes' cross‐sections was evaluated by scanning electron microscopy. The experiment of ion diffusion by dialysis showed that the ion diffusion coefficient of CA membrane is comparable to that found in the literature for membranes of commercial cellulose triacetate, 8.47 × 10^?8 cm² s^?1, while the ion diffusion coefficient of blends decreased as PS was added to the system. Regarding transport driven by pressure, CA membrane presented low rejection of PEG 80 kDa. These results showed that CA membrane could be used in a range of application comprehending the process of ultrafiltration or microfiltration. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers.     

Pervaporation separation of water–isopropyl alcohol mixture by PVA/LiBr membrane

Hydrophilic polyvinyl alcohol membranes, modified by lithium bromide, were prepared with glutaraldehyde as a crosslinking reagent. The membranes were investigated for the pervaporation dehydration of a water–isopropyl systems. The effect of the feed temperature on permeation flux and membrane selectivity was studied. The characterization of modified membranes was performed using Fourier transform infrared spectroscopy (FT‐IR), differential scanning calorimeter (DSC) and X‐ray diffraction. It was observed that the crystallinity of membranes increased as lithium bromide was added to the polymer. High performance liquid chromatography (HPLC) was used to analyze water content and isopropyl alcohol in the feed and permeate samples The pervaporation tests also confirmed an enhancement in water permeability through adding LiBr to the polymer, because of the high hydrophilic properties of this salt. According to pervaporation experiments conducted at 50°C, the water flux increased from 0.1049 kg/ m² hr to 0.1114 kg/ m² hr as 0.5 wt% of LiBr was added to the polymer matrix. Furthermore, an addition of 1 wt% of LiBr compared to homogeneous PVA membrane increased selectivity from 76 to 779. POLYM. ENG. SCI., 59:E101–E111, 2019. © 2018 Society of Plastics Engineers