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Hsu and T. Perfluorosulfonic Acid Membranes for Fuel Cell and Electrolyser Applications. Tulyani4 and J. Although the room-temperature conductivity of a 1100 EW Gore-Select Nafion/PTFE membranes is lower than that of a Nafion membrane, the resistance of the whole membrane of a Nafion/PTFE composite membrane is significantly lower Nafion has received a considerable amount of attention as a proton conductor for proton exchange membrane (PEM) fuel cells because of its excellent thermal and mechanical stability. It possesses high chemical, me- chanical and thermal stability. This was attributed to an initial decomposition reaction strongly influenced by the strength of . How- ever, Nafion® easily expands or Nafion membrane in order to improve the water retention, thermal stability, proton conductivity and methanol permeability. Nafion – 1,2,4-triazole composite membrane had high thermal and mechanical properties, and also showed high proton conductivity of 0. But, as mentioned by M. 1 Higher temperatures of operation are desirable, Furthermore, Nafion has a perfluorinated back-bone, rendering it oxidation resistant, an important feature for use in the highly oxidizing environments required for water oxidation. Water at Room Temperature and Normal Pres-sure After Iterative Contact with a Nafion® Poly-mer Membrane Elia V 1, Ausanio G4, De Ninno A3*, Gentile F, Germano R2, Napoli E1 and Niccoli M1 1Department of Chemical Sciences, University of Naples “Federico II”, Complesso Universitario Monte Sant’Angelo, Via Cinthia 80126, Naples, Italy The thermal stability of Nafion increases with incorporation of TNTs. humidification and temperature stability. Morphological changes in the structure were analyzed using SEM analysis. properties of Nafion, the most widely used electrolyte for DMFC applications [5-7]. e. An opposite effect on the thermal stability of the blends was caused by the addition of 3‐APTEOS. Various Nafion ®/silicate nanocomposites were understanding of the glass transition temperature of Nafion®, determining the effect of thermal annealing treatments on the morphology and mechanical properties of dispersion-cast Nafion®, and examination of dispersion-cast Nafion® subjected to an ex-situ, Fenton’s chemical degradation test. FENG and P. The TG curves of Nafion with alkali countercations show similar profiles, whichever the atmosphere employed. We attribute this inverse relationship of thermal stability with counterion size to an initial Nafion ® (Du Pont), the prototypical perfluorinated ionomer, has been the benchmark material in the fuel cell industry for several decades owing to its high proton conductivity and good chemical and thermal stability. improvement in mechanical stability is due to the good interaction of PVDF and Nafion side chains observed with FT-IR. Normal Nafion will lose proton conductivity when the temperature exceeds 80 °C and a significant drop of proton conductivity is observed at 120 °C. Previously the decrease of proton conductivity, ion exchange capacity (IEC), water uptake, and thermal stability changes of Nafion membrane had been researched. Nafion water using proton exchange membrane (PEM)   tivity data are presented as a functlon of HBr concentration and temperature . Gierke, “ Ion-transport and clustering in nafion perfluorinated membranes,” J. Casciola et al. He b* The increased temperature raises the evaporation rate of water from the membrane and the vapor pressure required to keep a given amount of water in the membrane. The chemical structure of the Nafion 117 membrane consists of a poly- tetrafluoroethylene backbone and a regularly  reported the protonic conductivity of a fully hydrated Nafion membrane up to thermal stability of Nafion, researchers modified the side chains of Nafion and  In the present study, Nafion/Titanium dioxide (TiO2) nanocomposite membrane with a good thermal resistance. 22° C. ton exchange membrane have different water and thermal C. With the aim of solving these problems, a non-Nafion polymer electrolyte membrane with low methanol permeability and high proton conductivity based on the sodium alginate (SA) polymer as the matrix and sulfonated graphene oxide (SGO) as an inorganic filler (0. Grant analogue and digital dry block heating systems From the most basic to advanced applications, with excellent temperature stability/uniformity and over-temperature thermal fuse for user safety VWR® sterile aerosol filter tips For PCR, DNA manipulations, radionucleotides work Nafion is a brand name for a sulfonated tetrafluoroethylene based fluoropolymer- copolymer of attention as a proton conductor for proton exchange membrane ( PEM) fuel cells because of its excellent thermal and mechanical stability. e. The properties that make the Nafion membrane indispensable are the combination of good water uptake, ion-exchange capacity, proton conductivity, gas permeability, and excellent electrochemical stability. 02 S/cm at the temperature of 160 °C under The Nafion® PFSA products have the extraordinary chemical and thermal stability of DuPont™ Teflon® ® resin is one of the most hydrophobic substances known, Nafion® perfluorosulfonic polymers is one of the most hydrophilic. It is a polymer, consisting of a long chain fluorocarbon backbone with pendent, sulfonic acid terminated, polyether side chains. Equivalent weight (EW) represents the number of grams of Nafion per mole of sulfonic acid group. Fuel cell performance of the composite membranes decreases with decreasing relative humidity, but good performance values are still obtained at 34% RH and 90 °C, with the best results obtained for solvent cast membranes Read "Nafion ® /ODF-silica composite membranes for medium temperature proton exchange membrane fuel cells, Journal of Power Sources" on DeepDyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. W. Mechanical properties of all the modified Nafion membranes were evaluated by a universal tensile machine (Labthink XLW) at 25 oC. The Young’s modulus decreases with increasing water content and temperature, is less temperature-dependent in hydrated The OCP is an important parameter in a DMFC in order to assess the methanol permeability of a membrane. In this respect, however, it is interesting to  Sep 2, 2017 Thermal stability of end‐capped and linear sulfonated polyimides, sulfonated polystyrene, and Nafion 117. 1016/j. F. Membr. HE: Molecular Model and Structural Stability Study of a Nafion, Kem. [26], the upper operation temperature limit of Nafion is low (only 80–100 °C). This is the first systematic report on the thermolysis products of Nafion by simulating its high-temperature operation and disposal process via incineration. 13, 307– 326 (1983). 1. This paper investigates the morphology and swelling of PFSA ionomers (Nafion and 3M) as bulk membranes (>10 μm) and dispersion-cast thin films (<100 nm) to identify the interplay between the equivalent weight (EW) and side-chain length across lengthscales, and how it governs the evolution of phase-separated nanostructure under confinement and The increases of the operating temperature and the water content in Nafion improve the proton transfer [18–23]. Ind. In contrast to the palladium membranes which have to be carried out at a high temperature, the resulted membrane can be operated at a low temperature (below 100°C) and is still stable in temperature up to 300°C. The effect on the direct EB-irradiation of Nafion membrane is not considered in this study because many previous studies have reported the results, as mentioned earlier, and identical EB-irradiation conditions were applied to Nafion membranes swollen in water and isopropanol. mechanical, thermal and chemical stability. PBI-based electrolyzer is relatively new to the hydrogen production technologies as compared to Nafion-based electrolyzer. Nafion® 117, Nafion® 115, Nafion® NR212 Nafion® NR211 membranes are non-reinforced films, and last numbers apply to their various thickness dimensions. At a high temperature of 135 °C, Su-CNTs/Nafion membranes maintained high proton conductivity because the reinforcement of Su-CNTs on Nafion matrices reduced the evaporation of water molecules from membranes as well as the hydrophilic Su-CNTs were helpful for binding water molecules. Compare Products: Select up to 4 products. As noted previously, its chemical resistance is similar to Teflon®, and very few things can attack it. We have found that the temperature of decomposition of Nafion is inversely dependent on the size of the exchanged cation; i. It is thus desirable to probe the combination of temperature and RH on the mechanical properties of materials to fully understand the environmental effects on structure and stability. Nafion™, was developed by Dr. The thermal stability of the perfluorinated cationexchange membrane Nafion-417 was determined by means of simultaneous TG-DTA. . 02-0 phosphate and ion-exchange resins (Nafion) as phosphorus concentration increased. 2016. 05. 32 µm (microns)Product cut to dimension +/- 1% at 50% RH The Nafion™ HP is an ultra-thin membrane that offers high power density. Given our recent success in electrodepositing a noble metal catalyst on an electrode surface, we sought to expand our work to surface-bound manganese catalysts. However, the fabricated composite showed very low chemical stability. Thermally stabilized PVA/Nafion® nanofibrous membrane was found to be stable against water, methanol and oxidative effects. 1 M VO 2 +/5 M H 2SO 4,BIpPBI displayed less degradation compared to a conventional hydrocarbon membrane, although Na on 115 had better chemical stability than both membranes, indicating that additional research for improving chemical stability of BIpPBI is needed. Chenliang Gong. 1, Mohammad Hassan. Higher temperature systems will improve the efficiency of oxygen reduction. Nafion membranes have been studied in acid and salt (alkali chlorides) forms. Polyphenylene Sulfonic Acid: a new PEM Sergio Granados-Focil and Morton H. *Please select more than one item to compare Nafion is a sulfonated tetrafluoroethylene based fluoropolymer-copolymer discovered in the late 1960s by Walther Grot of DuPont. Bocarsly3, S. Litt Department of Macromolecular Science and Engineering, Case Western In the case of Nafion ® (Nafion 115, DuPont) the conditions were: temperature, 125 ºC; pressure, 5 MPa, and pressing time, 2 min; for Aquivion (E87-12S, Solvay), the hot pressing was made at temperature of 160 ºC, pressure 1 MPa, and pressing time of 2 min. Thermal stability test for determining degradation/decomposition  The effect of humidity on the chemical stability of two types of membranes i. The effect of humidity on the degradation of Nafion (R) membrane Article in Polymer Degradation and Stability 94(9):1436-1447 · September 2009 with 58 Reads DOI: 10. A Comparison of Physical Properties and Fuel Cell Performance of Nafion and Zirconium Phosphate/Nafion Composite Membranes Chris Yang1,2, S. The annealing processing is responsible to increase a crystallinity in the nanostructure of pristine membrane. fluorinated sulfonic acid membrane (such as Nafion® series) on water. 7 Nafion®117 membrane stability in water electrolysis at elevated  According to DuPont, only metallic alkali metals (sodium in particular) can attack Nafion™ directly under normal conditions of temperature and pressure. The repeat structure of Nafion is shown in Figure 1. 2. However, most consumer products are subject to a variety of both temperature and relative humidity (RH) conditions during processing, storage, and end use. Nafion™ was the first synthetic polymer ever developed with ionic properties, and it started an entirely new class of polymers called ionomers. • Nafion ® 117 membrane stability in water electrolysis at elevated temperature. The proton conductivity of Nafion slightly increases when 0. A NetzschSTA 409 PC TG-DTA instrument was applied for the thermal stability study for the modified membrane from 30 oC to 800 oC under nitrogen atmosphere. 2, Kenneth Mauritz. Incorporation of amorphous phosphate into Nafion caused a large increase of conductivity to about 4xl0'S/cm at 23'C. The mechanical durability and enhanced chemical stability of the Nafion™ XL membrane are the result of an advanced stabilization system that increases mechanical strength and provides resistance to peroxide attack, resulting in improved membrane life and performance. In aqueous and organic systems with proton-donating solvents, the maximum temperature is higher; for example, stability in aqueous systems at 220–240 °C (428–464 °F) has Thickness: 20,32 µm (microns)Product cut to dimension +/- 1% at 50% RH The Nafion™ HP is an ultra-thin membrane that offers high power density. 2009. 5-2. Nafion contains a polytetrafluoroethylene  The thermal decomposition of Nafion® has been studied by means of high- resolution and constant heating rate thermogravimetry (TG), under nitrogen and  backs. Fenga and P. Project Introduction. Nafion membranes, along with their chemical and mechanical stability, makes them favorites in applications with temperature of operations up to 80 °C. decreased in high temperature (>80℃) and/or low humidity state, because of ion channel is sensitive for temperature and the percentage of water content. 0 wt%. However, the Nafion-propyl-1,2,3-triazole membrane was required more improved chemical and mechanical stability. A specially designed creep apparatus with environmental controls was used. Their distinguishing features include lower temperature/pressure ranges (50 to The reduced water uptake of GO/Nafion membranes was due to the restricted dimensional change of the membrane by GO reinforcement. Stability in aqueous systems at 220- 240˚C has been demonstrated for several days. Degradation of Nafion membranes at high temperatures is a serious challenge is to improve the membrane properties in terms of thermal stability and. 3. 65  proton exchange membrane (PEM) fuel cells because of its excellent thermal and mechanical stability. The glass transition temperature of Nafion limits the upper temperature ranges to about 100°C. 2003). The kinetics of thermal decomposition of the Nafion-Cs + has also been studied. Nafion has been shown to be stable in cell cultures as well as the human body, and there is considerable research towards the production of higher sensitivity glucose sensors. In aqueous and organic systems with proton-donating solvents the maximum operating temperature is higher. The DMFCs based on Lap/Nafion and Swy/Nafion membranes showed similar behavior in the temperature range from 90 °C to 110 °C, whereas the cell equipped with the filler-free membrane evidenced a lower value of OCP. Proton-exchange membrane fuel cells, also known as polymer electrolyte membrane (PEM) fuel cells (PEMFC), are a type of fuel cell being developed mainly for transport applications, as well as for stationary fuel-cell applications and portable fuel-cell applications. Anion Exchange Membranes Derived from Nafion Precursor for the Alkaline Fuel Cell A Thesis Submitted to the Faculty of Drexel University By Holly Lynn Schaeffer Salerno Nafion membrane (perfluorinated sulfonic acid polymers) is the ideal membrane for vanadium redox flow battery which possesses high ion selectivity, conductivity, good electrochemical and heat stability. 21,22 The structure of dry Nafion ® consists of a hydrophobic perfluorocarbon Although Nafion will tolerate temperatures as high as 190°C, a maximum operating temperature of 150°C for Nafion dryers and humidifiers is recommended. B. The method employed to calculate the kinetic parameters and to estimate the Nafion ® 117 conductivity at temperature up to 150 °C and pressure up to 0. Palmer Among the various Nafion – azole composite membranes, Nafion – 1,2,3-triazole membrane showed excellent flexibility, thermal stability, and homogeneous structure. We should remark in this connection that dry (water-free) Nafion samples are commonly stored in our laboratory at room temperature, i. May 19, 2009. However, the high cost of purchasing Nafion membrane and inability to execute electrolysis operational above 90°C has sparked new interest on PBI-based membrane, which is known for its good thermal stability. The chemical basis of Nafion's superior conductive properties remain a focus of research. However, the membrane must remain stable and sustain hydration and ionic conductivity at higher temperature. 1 Literature review The chemical structure of Nafion is shown in Figure 1. Feb 15, 2018 To overcome the disadvantages of Nafion®, Sulfonated poly (ether ether . oxidant and exceptional mechanical and chemical stability [24-25]. Nafion (a product of DuPont) is the most common membrane separator used in PEMFCs because of its chemical and thermal stability and its high proton conductivity. University of Tennessee . The photoluminescence arises because of the presence of sulfonic groups attached to the ends of the perfluorovinyl ether groups that form the tetrafluoroethylene (Teflon) backbone of Nafion. At higher temperatures, this membrane steadily releases water, with a concomitant decrease in proton conductivity. Nevertheless, use of room-temperature ionic-liquid (RTIL)-based PEMFC is starting to attract interest, essentially because they do not exhibit the daunting water management problems that complicate practical use of PEMFCs. Operation of these fuel cells for extended periods of time at temperatures approaching 100°C introduces concerns of the thermal stability of the Nafion electrolyte  The thermal decomposition of Nafion has been studied by means of high- resolution and constant heating rate thermogravimetry (TG), under nitrogen and  The effect of exchanged ions on the thermal stability of Nafion N117CS membranes was investigated by X-ray photoelectron spectra (XPS), thermogravimetric  Nafion™ tubing is very stable at high temperatures. Spry and Fayer investigated the proton concentration in the center of the water pools in Nafion by HPTS. These electrolytes are temperature from *80 to *130 °C [2]. 2 1. DuPont's Nafion ® perfluorosulfonic acid cation-exchange membranes possess many desirable properties for PEM fuel cells which operate at a temperature £ 80°C, including high proton conductivity under fully hydrated conditions and good thermal and oxidative stability. The membrane is reinforced and designed for lower relative humidity environments and high operating temperature. [12] who found that stability improves as counterion size decreases. membrane electrolysis and membrane fuel cells) [1–3]. 2001; Li, He et al. In FY 2006, we not only continued to develop alternative polymer electrolyte but also made efforts to develop non-Nafion ® ionomers which may • • • • • V. the thermal stability of PFSA As follows from the graphs in Figs. Nafion R1100 in a protonated form was used, and TNT contents were in a range of 0. The modified Nafion nanocomposite membranes were used for high temperature fuel cell between 120-140°C. For lower starting water contents in Nafion 117, the low temperature conductivity decreases rapidly with water contents . The swelling of a polymer ion-exchange membrane Nafion in water with various heavy isotope contents (D2O) was studied by photoluminescent UV spectroscopy. The methanol (MeOH) permeability and proton conductivity result of Nafion and it PVDF blend Sulfonated graphene oxide/Nafion composite membranes for high temperature and low humidity proton exchange membrane fuel cells Supporting information Fig. Jan 1, 2008 The effect of humidity on the chemical stability of two types of membranes longer, and have higher glass transition temperatures than Nafion. 1. The membrane sample was cut Both the blend membranes were flexible. 15255/KUI. 017 KUI-30/2016 Original scientific paper Received April 22, 2016 Accepted July 25, 2016 C. higher temperatures the mechanical stability is reduced resulting in crack formation and crossover of the fuel. of conventional, Nafion-based PEMFCs. 5 micrometers (1. 1-4 In order to achieve higher temperature stability, either new polymer membranes have to be developed or established materials like Nafion have to be modified. et al. One of the preferred ionomer materials for these devices is Nafion® [2], a perfluorosulfonic acid (PFSA) is a trademark product of DuPont, because of its superior proton conductivity and chemical stability. The effect of exchanged ions on the thermal stability of Nafion N117CS membranes was investigated by X-ray photoelectron spectra (XPS), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), thermomechanical analysis (TMA), and ion exchange capacity determinations. Nafion has received a considerable amount of attention as a proton conductor for proton exchange membrane (PEM) fuel cells because of its excellent thermal and mechanical stability. Even so, operating PEMFC at a high temperature (>1 00°C) has many benefits (Yang, Costamagna et al. When the water bath (approximately 20 °C) is infused into the chamber, the small temperature difference means that the ribbon must adopt a new thermal equilibrium. For example, Nafion™ N117, used in fuel cells and sealing applications, is sold in the H+ form. Mechanical properties, including the Young’s modulus and limits of elastic deformation are dependent on temperature and membrane water content. 2,3 2. Nafion™ perfluorinated membranes are produced either in the H +, Na , or K form, depending on the intended use. m in Figure 1-2 is related to EW by EW = 100m+446 21 . The individual decomposition stages were studied via IR spectroscopy and ion-exchange capacity determinations. A common MODIFICATION AND EVALUATION OF FUEL CELL MEMBRANES by Amol Prataprao Nalawade May 2011 The primary goals of this study were modification of existing Nafion ® membranes and characterization of newly developed hydrocarbon-based membranes for high temperature fuel cell applications. It will absorb water and some polar organics rapidly, even at room temperature, in Among the various Nafion – azole composite membranes, Nafion – 1,2,3-triazole membrane showed excellent flexibility, thermal stability, and homogeneous structure. The chemical The impact of pre-swelling on the conductivity and stability of Nafion/sulfonated silica composite membranes Nafion at temperature higher than 90˚C dehydrates, which severely hampers the transport of proton in the form of hydronium ions. Abstract. Membranes used temperature PEM systems. polymdegradstab. Nafion® XL membranes are newly developed reinforced membranes that enhance the chemical stability of Nafion® membranes. S1 Optical photographs of dissolution of Fe3O4 nanoparticles in 1 M H2SO4 at 70 ℃ at (a) 0 mins, (b) thermal stability, and ion exchange capacity of the Nafion 117 membrane. • Relation between the membrane conductivity and volumetric expansion. Figure 6. excellent thermal and chemical stability. In air at room temperature (18 – 19 °C), both the Nafion tube and silver ribbon are in thermal equilibrium. Benziger4,5 Princeton University Princeton, NJ 08544 The physio-chemical properties of Nafion 115 and a composite Nafion 115/Zirconium have desirable interfacial compatibility with Nafion ®-bonded electrodes. Firstly, it avoids the existence of two phase flow in the flow field, thus enhances the stability & reliability of PEMFCs system. The maximum continuous operating temperature of nafion perfluorinated sulfonic acid copolymer is about 175˚C in anhydrous systems. Modified Nafion for PEM fuel cells. A reduced MeOH permeability was observed with 2. These properties are strongly influenced by the equivalent weight (EW), water content, nature of solvent, exchanged cations and temperature. Two layers of PTFE were used to sandwich the Nafion layer, providing the Nafion with stability up to 300°C. The increase in the thermal stability of the blends with the increase in the 3‐APTEOS content was assigned to the neutralization of the acid groups of Nafion by the formation of an ionic complex. [1] It is the first of a class of synthetic polymers with ionic properties which are called ionomers. It was found that the effects of temperature and hydration on Nafion’s viscoelastic response are very complicated. D. Srinivasan3, A. Normal Nafion will dehydrate (thus lose proton conductivity) when temperature is above ~80 °C. 02 S/cm at the temperature of 160 °C under chemical stability, and mechanical toughness28. The acid-treated composite membranes, at lowest inorganic additive content, exhibited improved properties in terms of thermal stability and methanol (MeOH) permeability. Y. 7 MPa. Thickness: 20. Despite its high proton conductivity and excellent chemical stability, Nafion performance, especially at high temperatures, is impaired by methanol crossover through the polymer membrane and by conductivity decay above 90 °C [8]. 5 wt% TNTs and then decreases with an increase in the amount of TNTs. The dimensional stability of the GO/Nafion membranes, before and after absorbing water, was also improved due to GO reinforcement. , longer, and have higher glass transition temperatures than Nafion and yet are  Results also denote that when operating at appropriate high temperatures (105 ºC for Nafion® and 125 ºC for Aquivion®), there is no need of incorporating  longer life, and wider relative humidity and temperature operating ranges. Jan 30, 2016 Nafion®117 conductivity at temperature up to 150 °C and pressure up to 0. SO −3. showed higher thermal stability in sulfonic acid bridge exhibit the higher degradation temperature than cast Nafion and shown in the cast Nafion at over 80 actuators [1]. The useful operating temperature is High temperature membranes for DMFC (and PEFC) •chemical and electrochemical stability Composite recast Nafion®-inorganic filler membranes Ionomer-Liquid Electrolyte Hybrid Ionic Conductor for High Cycling Stability of Lithium Metal Electrodes micron-thick Nafion layer on Li stability levels or low room-temperature ionic Effects of curing condition of solution cast Nafion® membranes on PEMFC performance Singaram Vengatesan, Eunae Cho†, Hyoung-Juhn Kim, and Tae-Hoon Lim Fuel Cell Research Center, Korea Institute of Science and Technology, 39-1 Hawolgok-dong, Sungbuk-gu, Seoul 136-791, Korea (Received 13 October 2008 • accepted 4 December 2008) stability test, in which the membranes were soaked into a solution of 0. • Elevated temperature and pressure impact on the Nafion ® 117 chemical stability. Molecular Model and Structural Stability Study of a Nafion Ionomer-Based Membrane Electrode Assembly DOI: 10. The composite membranes showed excellent thermal stability, allowing for operation in medium temperature PEM fuel cells. The high methanol crossover and high cost of Nafion® membrane are the major challenges for direct methanol fuel cell application. University of Southern Mississippi. transition temperature at a given polymer EW (Tg Nafion stability (arising from The dependence of the thermal degradative stability of Nafion® on the nature of the SO. 21. Walther Grot at DuPont in the late 1960’s by modifying Teflon®. PERSONAL PROTECTIVE and unswollen state, good thermo-stability, and thinner thickness (thickness ~ 20 μm). CiteSeerX - Document Details (Isaac Councill, Lee Giles, Pradeep Teregowda): ABSTRACT: The current study uses variable temperature, small-angle X-ray scattering (SAXS) to examine the thermal relaxation behavior of oriented Nafion films as a means to evaluate the morphological stability of this ionomer at elevated temperatures. change the thermal stability of Nafion. Nafion membranes are widely used for Proton Exchange Membrane (PEM) fuel cells and hydratation stability at high temperatures and thermal stability [2]. Nafion®, a perfluorosulfonate ionomer, is measured for Nafion and for Nafion/TiO2 composite membranes. Nafion™ 900 and 2000 series membranes used for NaOH production are sold in the Na+ form. The MEA was then placed between two high-density graphite plates with serpentine type Read "Design of new selective Nafion membranes using room temperature ionic liquids, Desalination" on DeepDyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. 5–7; (2) an additional proton con- Nafion® is one of promising perfluorinated polymers which has been widely used as a proton conducting electrolyte membrane due to its high proton conductivity and chemical stability. Nafion is a strong acid catalyst and, as operating temperatures rise above 110°C, unwanted chemical reactions may be stimulated within the sample gas matrix. The inorganic nanoparticles were incorporated within Nafion by recast, swelling-impregnation and ion exchange methods. In view of the laboratory tests performed at PSI with a Nafion tubular membrane reactor module for the catalysed methanol synthesis with CO2 and H-2 at 200 degrees C, the mechanical stability of a commercially available Nafion hollow fiber was tested at elevated temperatures (T=160-200 degrees C) and pressures (P<30 bar). A number of investigators have tried to prevent the loss of water at elevated temperature from the ionic pores of Nafion by modifying the membrane for use in polymer Swelling degree of HSS/Nafion® composite membranes HSS addition as shown in Figs. 016 Thermal, water, methanol and oxidative stability of the membranes were tested in addition to ion-exchange capacity. 3 Mechanistic Aspects of Proton Conductivity (Nafion and PFSAs) . While Teflon® resin is one of. The thermal stability of end-caped and linear sulfonated polyimides (SPIs), sulfonated polystyrene (SPS), and a sulfonated perfluorinated hydrocarbon, Nafion 117, and the corresponding triethylammonium sulfonate salts was investigated by dynamic and isothermal thermogravimetric analysis (TGA). 6 and 7, water close to Nafion interface “remembers” the scenario of changing its temperature. group counterion was studied by Feldheim . There is a stability, glass transition, and water retention of Nafion great interest in the elevation of the PEMFC operating based polymer–ceramic electrolytes. 0 wt% TNTs nanocomposite membrane. The as-received H-form Nafion membrane is not stable at elevated temperature. The viscoelastic response of Nafion was measured over a range of temperature and hydration using viscoelastic creep. Nafion is a Stress-Strain Curves of Nafion Membranes in Acid and Salt Forms Yoshio Kawano Instituto de Química, USP Yanqia Wang, Richard A. The Giner Dimensionally Stable Membrane (DSM™ membrane) shows stellar mechanical stability compared to the “gold-standard” DuPont Nafion® 112 ( Nafion)  The thermal stability of Nafion membrane was increased by all studied nine chemical, electrical and thermal properties the room temperature ionic liquids are   increasing temperature, which eventually surpassed that of neat Nafion above 100 o improved thermal stability of the impregnated membrane showing light. However, thermal stability of the Nafion membrane significantly improved after the countercations of the membrane had The maximum continuous operating temperature of Nafion™ perfluorinated sulfonic acid copolymer is about 175 °C (347 °F) in anhydrous systems. Nafion possesses the desired stability and adequate transport properties for. 7 Non-Nafion ® Membrane Electrode Assemblies. As far as BP material stability in ionic liquids is concerned, a very limited amount Search results for nafion at Sigma-Aldrich. Nafion films show improved thermal stability as the size of the counter cation decreases. In recent years, there has been effort to develop new cost effective polymer electrolyte membrane (proton exchange type) for the application in PEMFC, which can be operated at high temperature. Around room At a high temperature of 135 °C, Su-CNTs/Nafion membranes maintained high proton conductivity because the reinforcement of Su-CNTs on Nafion matrices reduced the evaporation of water molecules from membranes as well as the hydrophilic Su-CNTs were helpful for binding water molecules. Tan delta versus temperature for Nafion/PVDF composites membranes prepared by melt-mixing process . The Nafion® PFSA products have the extraordinary chemical and thermal stability of DuPont™ Teflon® fluoropolymer resins. X + electrostatic interactions. Sci. 1 mil) thick. An annealing treatment was conducted at the temperature of 180 o C for 3 h. Nafion™ XL is 27. Yu Seung Kim (Primary Contact), Jerzy Chlistunoff, and Poly(cyclohexadiene)-Based Polymer Electrolyte Membranes for Fuel Cell Applications Jimmy Mays 1, Suxiang Deng. Abstract Nafion is widely used as the polymer electrolyte in proton exchange membrane (PEM) fuel cells. This presentation does not contain any proprietary, confidential, or otherwise restricted information. nafion temperature stability

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