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A novel hydrogel polymer electrolyte was prepared by incorporation of 1,4‐butanediol diglycidyl ether (BG) to cross‐linked polyacrylamide (PAM). The electrolyte (PAMBG) was modified with cobalt (II) sulfate with various doping ratios (PAMBGCoX) to increase the capacitance by increasing faradaic reactions. The supercapacitor device assembly was performed by using active carbon (AC) electrodes and hydrogel polymer electrolytes. The specific capacitance of the PAMBGCo5 device indicated 130 F g−1, which is at least a seven‐fold improvement due to the insertion of Co as a redox component. The electrolyte device, PAMBGCo5, displays superior performance having an energy density of 38 Wh kg−1 at a power density of 500 W kg−1. Additionally, with the same hydrogel, the device performed 10,000 galvanostatic charge‐discharge cycles via retaining 91% of the initial capacitance. A cost‐effective electrolyte, PAMBGCo5, was tested in a carbon‐based supercapacitor under bent and twisted conditions at various angles, confirming the robustness of the device. [ABSTRACT FROM AUTHOR]

Summary: The fabrication of flexible supercapacitors was achieved by employing the novel redox‐activated polymer electrolytes comprising poly(vinylphosphonic acid) (PVPA) and nickel nitrate Ni(NO3)2, Ni. The hydrogels, PVPA/NiX, were produced in various contents, in which X denotes the doping fraction of Ni in PVPA. The structure, thermal, and morphology of the materials were characterized, and then they were applied for construction of supercapacitors. The performance evaluations of the fabricated devices were carried out by electrochemical impedance spectroscopy, galvanostatic charge‐discharge, and cyclic voltammetry experiments. Flexible supercapacitor devices assembled with activated carbon (AC) electrodes and PVPA/NiX hydrogels produced 793 F g−1 specific capacitance with 30 times enhanced capacitance compared with Ni‐free system. The energy density of 103.1 Wh kg−1 was yielded from the device at a power density of 500 W kg−1. The supercapacitor demonstrated an excellent performance during 5.000 charge‐discharge cycles, while preserving 84% of its initial capacitance. The supercapacitor constructed of 1 × 5 cm dimension, successfully operates the LED after charging at 3 V. [ABSTRACT FROM AUTHOR]

Flexible supercapacitors were constructed by using novel redox‐mediated polymer electrolytes including poly (2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid) (PAMPS) and ammonium molybdate [(NH4)2MoO4] (Mo). The gel polymer electrolytes PAMPS/Mox were prepared in different compositions, where x represents the doping ratio of Mo into PAMPS electrolyte. The structure and morphology of the electrolytes were elucidated by using various spectroscopic and microscopic methods, and then they were used in the fabrication of symmetric supercapacitors. The electrochemical performances of the devices were investigated by using cyclic voltammetry, galvanostatic charge‐discharge, and electrochemical impedance spectroscopy. The system containing active carbon as the electrode and PAMPS/Mo3 as the electrolyte produced a maximum specific capacitance of 530 F g−1 with a 30 % enhancement in capacitance compared to the Mo‐free supercapacitor. The energy density of the device is 73 Wh kg−1 with a power density of 580 W kg−1. The redox‐active hydrogel‐based supercapacitor exhibited an excellent performance even after 2500 charge‐discharge cycles, maintaining 92 % of its original capacitance. A flexible supercapacitor was assembled by using PAMPS/Mo3 electrolyte and successfully operated a light‐emitting diode (LED). [ABSTRACT FROM AUTHOR]

In the present work, boron-doped multicomponent gel polymer electrolytes composed of host polymer, sulfonated polysulfone (SPSU) and the additives; ionic liquid, 1-ethyl-3-methyl-imidazolium tetrafluoroborate (IL), H3BO3, polyphosphoric acid (PPA) were prepared. Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA) techniques were used to characterize the sulfonated polysulfone-based electrolytes. Ion conductivity of these gel electrolytes were studied by dielectric impedance analyzer within the temperature from −20 to 100°C. The ionic conductivity of the SPSU-5IL-1PPA and SPSU-5IL-1H3BO3-1PPA were measured as 4.8 × 10−3 and 9 × 10−4 S cm−1, respectively. Supercapacitor having activated carbon-based composite electrode and electrolyte was constructed with the configuration: Al/C/electrolyte/C/Al. The electrochemical properties and ion transfer characteristics of the supercapacitor were investigated by the cyclic voltammetry (CV). Galvanostatic charge—discharge experiments exhibited good electrochemical reversibility and produced a specific capacitance value of 120 F g−1 at 1 A g−1. The symmetric supercapacitor system was retained almost 85% of its initial activity after 1000 cycle. [ABSTRACT FROM AUTHOR]

Single-ion polymer electrolytes are expected to play an important role in the development of next-generation lithium batteries. The current work focuses on the designing of novel solid single-ion conducting inorganic polymer electrolytes based on lithium polyacrylic acid oxalate borate (LiPAAOB) and poly(ethyleneglycol) methacrylate (PEGMA). PEGMA is polymerized into PPEGMA via free radical polymerization and LiPAAOB is prepared from poly(acrylic acid), oxalic acid and boric acid. Blend polymer electrolytes were produced by mixing of LiPAAOB with PPEGMA at different weight fractions to enhance the single ion conductivity of the system. To exploit the flexible chemistry and increase segmental mobility of the blend electrolyte, the composition was changed up to 80% with respect to PPEGMA. FT-IR and differential scanning calorimeter technique verifies the interaction between the host and guest polymers. Thermogravimetry analysis verified that the thermal stability of the blends increased up to approximately 200 °C. Scanning electron microscopy images confirm the homogeneity of the blend electrolytes. Cyclic voltammetry studies showed that electrochemical stability electrochemical stability window is approximately 5 V versus Li/Li+. The effect of PPEGMA on to the Lithium ion conductivity was investigated using dielectric impedance analyzer. The maximum single ion conductivity was measured as 1.3 × 10−4 S/cm at 100 °C for the sample LiPAAOB-80PPEGMA. Clearly these results confirmed the positive effect to the increment in ionic conductivity of the blend electrolytes with the addition of PPEGMA. [ABSTRACT FROM AUTHOR]

Heterocyclic molecules are generally used in the proton conducting membranes as dopant or polymer side group due to their high proton transfer ability. Composite proton conducting membranes based on poly(vinylphosphonic acid) (PVPA) and poly(5-(methacrylamido)tetrazole) (PMTet) were produced. The homopolymers, prepared from their corresponding monomers, were blended at several mol ratios to obtain the polymer electrolyte membranes. All samples were characterized by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA), differantial scanning calorimetry (DSC), cyclic voltammetry (CV), and impedance analysis. Besides, the morphology of the membranes was studied by X-ray diffraction (XRD), atomic force microscopy (AFM) and scanning electron microscopy (SEM). FTIR spectra confirmed the formation of hydrogen bonding network between PVPA and PMTet units. TGA showed that the polymer electrolyte membranes were thermally stable up to ∼210°C. CV curves demonstrated the oxidative stability of the samples in 3 V region. In anhydrous conditions, the maximum proton conductivity was determined as 0.06 Scm−1 at 150°C for PMTetP(VPA)4. POLYM. ENG. SCI., 55:260-269, 2015. © 2014 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Polymer electrolyte membranes (PEMs) are synthesized via in situ polymerization of vinylphosphonic acid (VPA) within a poly(2,5-benzimidazole) (ABPBI) matrix. The characterization of the membranes is carried out by using Fourier transform infrared (FTIR) spectroscopy for the interpolymer interactions, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) for the thermal properties, and scanning electron microscopy (SEM) for the morphological properties. The physicochemical characterizations suggest the complexation between ABPBI and PVPA and the formation of homogeneous polymer blends. Proton conductivities in the anhydrous state (150 °C) measured by using impedance spectroscopy are considerable, at up to 0.001 and 0.002 S cm−1 for (1:1) and (1:2) molar ratios, respectively. These conductivities indicate significant improvements (>1000×) over the physically blended samples. The results shown here demonstrate the great potential of in situ preparation for the realization of new PEM materials in future high-temperature and non-humidified polymer electrolyte membrane fuel cell (PEMFC) applications. [ABSTRACT FROM AUTHOR]

High performance of PVDF and design feature of glycidyl methacrylate (GMA) were combined in a graft copolymer with a goal of being used in fuel cells. PVDF- g-PGMA was obtained via atom transfer radical polymerization (ATRP) of GMA on a PVDF matrix using a 'grafting from' approach. Specifically, AGET (activators generated by electron transfer) ATRP was employed in the surface grafting, which produced acceptable grafting degrees. Synthesized PVDF- g-PGMA copolymer was modified with 5-aminotetrazole and doped with triflic acid (TA) at different mole ratios with respect to aminotetrazole units, eventually fabricating various PVDF- g-PGMA-ATet-(TA)x membranes. The composition and the structure of polymers were characterized by Energy Dispersive X-ray spectroscopy (EDS), H-NMR and FTIR. Their thermal properties were examined by thermo gravimetric analysis (TGA) and differential scanning calorimetry (DSC). TGA demonstrated that the PVDF- g-PGMA and PVDF- g-PGMA-ATet-(TA)x membranes were thermally stable up to 275 °C, 200 °C ( x = 2.0) and 230 °C ( x = 4.0). According to EDS results, 71.35 % functionalization with 5-aminotetrazole was achieved. PVDF- g-PGMA-ATet-(TA) showed a maximum proton conductivity of 0.011 Scm at 150 °C and anhydrous conditions. [ABSTRACT FROM AUTHOR]

ABSTRACT Anhydrous polymer electrolytes based on azole functional methacrylates and methacrylamides have been produced for use in proton exchange membrane fuel cells (PEMFCs). Poly(methacryloyl chloride) (PMAC) was prepared first by free-radical polymerization of methacryloyl chloride, followed by side chain functionalization with 5-aminotetrazole (ATet), 3-amino-1,2,4-triazole (ATri) and 1H-1,2,4-triazole (Tri). Finally, the obtained polymers were doped with triflic acid (TA) at stoichometric ratios of 1.0, 2.0 and 4.0 with respect to azole units, and the anhydrous polymer electrolytes were obtained. The membranes were characterized by FT-IR, 13C-NMR, and elemental analysis. Thermal behaviour of polymers was explored by TGA and DSC. The samples were thermally stable up to approximately 200 oC. Proton conductivity was measured by impedance spectroscopy. Trifilic acid doped poly(methacryloyl aminotetrazole) (PMAATet-(TA)4), poly(methacryloyl-3-amino-1,2,4-triazole) (PMA-Tri-(TA)4), and poly(methacryloyl-1,2,4-triazole) (PMA-ATri-(TA)4) showed maximum proton conductivities of 0.01 Scm−1, 0.02 Scm−1 and 8.7x10−4 Scm−1, respectively, at 150°C and anhydrous conditions. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39915. [ABSTRACT FROM AUTHOR]

Copolymer electrolytes based on 5-(methacrylamido)tetrazole (MTet) and vinyl phosphonic acid (VPA) are prepared. The obtained copolymers are analyzed by FTIR, 1H NMR, 13C NMR, and 31P NMR spectroscopy, thermogravimetric analysis (TGA), differantial scanning calorimetry (DSC), energy dispersive X-ray spectrometry (EDS), elemental analysis (EA), cyclic voltammetry (CV), and impedance spectroscopy. The morphology of the copolymers is characterized by X-ray diffraction (XRD), atomic force microscopy (AFM) and scanning electron microscopy (SEM). The highest proton conductivity is obtained as 0.01 S/cm at 150 °C and in anhydrous conditions. [ABSTRACT FROM AUTHOR]

In this work, acid-base complex pair polymer electrolyte membranes on sulfonated polysulfone with 1H-benzotriazole were investigated. Polysulfone was sulfonated in 1,2-dichloroethane using the homogeneous method with trimethylsilyl chlorosulfonate as sulfonating agent. The monomer mole ratio between polysulfone and trimethysilyl chlorosulfonate was 1:1.5. The sulfonated polysulfone was added with 1H-benzotriazole at mole ratios of x = 0.5 and x =1. The proton transfer from 1H-benzotriazole to the sulfonated polysulfone was measured using FTIR. Thermo-gravimetry analysis showed that the samples were thermally stable up to approximately 250°C and the maximum proton conductivity was found to be 3.34 x 10-4 S cm-1 at 150°C. [ABSTRACT FROM AUTHOR]

Poly(4-vinylbenzeneboronic acid), PVBBA was synthesized via free-radical polymerization of 4-vinylbenzeneboronic acid (4-VBBA) and followed by crosslinking with polyethylene glycol (PEG) with different molecular weights to produce boron containing crosslinked polymers. Prior to crosslinking, the materials were doped with CF3SO3Li at several stoichiometric ratios to get PVBBAPEGX-Y where X is the molecular weight of PEG and Y is the EO/Li ratio. The materials were characterized by using Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA) and differential scanning calorimeter (DSC). The ionic conductivity of these novel crosslinked electrolytes was studied by dielectric-impedance spectroscopy. Li-ion conductivity of these polymer electrolytes depends on the length of the side units as well as the doping ratio. PVBBAPEG200-10 illustrated a satisfactory ionic conductivity of 3.1 × 10−5 S/cm at 20 °C and 1.8 × 10−3 S/cm at 100 °C. [ABSTRACT FROM AUTHOR]

Polymer electrolytes that have ability to conduct protons at high temperatures have become crucial as the membranes for proton exchange membrane fuel cells (PEMFC) in anhydrous systems. In this work, a novel copolymer based on 5-(methacrylamido)tetrazole (MTet) and vinyl triazole (VTri) was prepared by conventional free-radical copolymerization at several monomer feed ratios to attain poly(VTri-co-MTet) copolymers. The copolymer samples were doped with HPO at several stoichiometric ratios to obtain proton conductive copolymer electrolytes. The obtained membranes were analyzed by FTIR, H-NMR, Thermogravimetric Analysis (TGA), Differantial Scanning Calorimetry (DSC), Scanning Electron Microscopy (SEM), Cyclic Voltammetry (CV), and Impedance Spectroscopy. The compositions and molecular weights of copolymers were determined via H-NMR analysis. TGA demonstrated that the copolymers are thermally stable up to approximately 220 °C. DSC results illustrated both the homogeneity of the materials by the appearance of a single T and the plasticizing effect of the dopant. SEM analysis provided further evidence for the homogeneity of the membranes. CV results demonstrated that the stability window of P(VTri-co-MTet) is 3 V. The copolymer electrolytes, P(VTri-co-MTet)2:1 X = 2, P(VTri-co-MTet)1:1 X = 2, and P(VTri-co-MTet)1:2 X = 2 showed maximum proton conductivities of 0.012 Scm, 0.014 Scm and 0.016 Scm, respectively, at 150 °C and anhydrous conditions. [ABSTRACT FROM AUTHOR]

In the present work, the synthesis, thermal and proton conducting properties of copolymers based on 4-vinylbenzeneboronic acid (VBBA) and 1-vinyl-1,2,4-triazole (VTri) were investigated. The copolymers were produced by free-radical copolymerization of the corresponding monomers at several monomer feed compositions to obtain copolymers which were abbreviated as P(VBBA-co-VTri). The copolymer samples were doped with HPO at several stoichiometric ratios to obtain proton conductive copolymer electrolytes. The composition of the copolymers was also determined by elemental analysis. The structure of the copolymer and the electrolytes were studied by FT-IR spectroscopy. The thermal properties were investigated by TGA which confirmed that the materials are stable up to at least 150 °C. In the absence of humidity, the copolymer electrolyte, P(VBBA-co-VTri)1:2 X = 3 has a proton conductivity of 6 × 10 S/cm at 120 °C. Cyclic voltammetry results demonstrated that the stability window of P(VBBA-co-VTri) is 4 V. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

As anhydrous proton conductive membranes, sulfonated polysulfone (SPSU) and 1H-1,2,3-benzotriazole (BTri) hybrid membranes were prepared. The sulfonation of polysulfone was performed with trimethylsilyl chlorosulfonate, and high degree of sulfonation (134%) was obtained. The polymer electrolyte membranes, SPSU–BTriX, were prepared by blending of 1H-1,2,3-benzotriazole in SPSU. FTIR confirmed the sulfonation of PSU and the ionic interaction between sulfonic acid and benzotriazole units. Thermogravimetric analysis (TGA) analysis showed that the polymer electrolyte membranes are thermally stable up to approximately 200 °C. Scanning electron microscopy analysis indicated the homogeneity of the membranes. The maximum proton conductivity has been measured for SPSU–BTri2 as 3.6 × 10−3S/cm at 150 °C. [ABSTRACT FROM PUBLISHER]

Proton conducting polymer electrolytes bearing phosphonic acid units are very promising due to their high conductivity, thermal and chemical stability. In the present work, proton conducting nanocomposite electrolytes containing poly(vinylphosphonic acid) (PVPA) and SiO were prepared by two different methods. The interaction existed between PVPA and SiO was confirmed by FT-IR spectroscopy. The surface roughness of the nanocomposites was studied using AFM. Thermogravimetric analysis revealed that the samples were thermally stable up to 200 °C. The glass transition temperature (Tg) of the materials were determined using DSC. In the anhydrous state, the proton conductivity of PVPA(10)SiO (in situ) was found to be 0,009 (Scm) at 120 °C. The proton conductivity of PVPA(10)SiO increased to 0.08 (Scm) at 50 % relative humidity. The SiO nanoparticles in the composite membranes improved the thermal properties and increased the proton conductivity. [ABSTRACT FROM AUTHOR]

Abstract: Fuel cells are gaining increasing attention as a clean and promising technology for energy conversion. One of the key benefits of fuel cells compared to other methods is the direct energy conversion that enables the achievement of high efficiency. The electrolyte membrane is the most essential parts of a fuel cell unit, and consequently has been the subject of considerable research and development. Among the various types of proton conducting electrolytes examined for fuel cell applications, polymer electrolyte membranes (PEMs) are regarded as viable candidates since they enable operation of the cells at desirably low temperatures. This review describes recent progress in the design and development of high performance proton conducting PEMs, including the analysis of the design requirements and strategies for development of advanced PEMs for operation in anhydrous conditions. Some of the most widely used types of azole heterocycles are introduced and compared, particularly in terms of their performance characteristics in polyacids containing different functional groups. In addition, the latest research studies and progress in the field of azole-containing and azole-functionalized electrolyte systems are discussed and reviewed. [Copyright &y& Elsevier]

In this work, we communicate on the synthesis, characterization, and ionic conductivity of a series of novel crosslinked inorganic-organic gel polymer electrolytes. These crosslinked polymers were prepared by the modification of poly(vinyl alcohol) (PVA) with poly(ethylene glycol) (PEG) in the presence of borane-tetrahydrofuran (BH3/THF) complex. During crosslinking, the polymer was doped with lithium trifluoromethane-sulfonate (CF3SO3Li) salt. Molecular weight of both PVA and PEG was varied, and the concentration of Li-salt was arranged for the ratio of lithium atoms to ether oxygen atoms. Boron-containing polymer electrolytes were produced and abbreviated as PVA1PEGX-Y and PVA2PEGX-Y. The reaction of PEG with PVA and the interaction of Li+ ions with EO units were confirmed by FTIR. Thermal stability of these materials was measured with thermogravimetric analysis, and thermal behaviors were measured by differential scanning calorimetry. The ionic conductivity of these novel polymer electrolytes was studied by dielectric-impedance spectroscopy. Li-ion conductivity of these crosslinked polymer electrolytes depends on the length of the side units as well as the doping ratio. The maximum ionic conductivity was measured as 10−4 S cm−1 at room temperature. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

Abstract: In this work, 3-glycidoxypropyl trimethoxy silane (GPTMS) was functionalized with 5-aminotetrazole (ATet) via ring opening of the epoxide ring and then sol–gel polymerization was performed to produce tetrazole containing silane networks abbreviated as Si-ATet. In addition during sol–gel process trifluoromethane sulfonic acid (TA) was introduced into the matrix with several stoichometric ratios (TA/ATet=0.5 and 1) to produce Si-ATetTA0.5 and Si-ATetTA1 polymer electrolytes. Fourier transform infrared spectroscopy (FT-IR) confirmed the tethering of the ATet into the silane compound and the sol–gel reaction, thermogravimetry analysis (TGA) showed that the membranes are thermally stable up to 180°C. Differential scanning calorimeter (DSC) verified the softening effect of the dopant and the homogeneity of the samples. The proton conductivity of these novel silane networks was studied by dielectric–impedance spectroscopy. Although proton conductivity of these membrane electrolytes depends on the doping level, the membrane without dopant produced a proton conductivity of 10−4 S/cm at 150°C in dry state. The conductivity isotherms show Vogel–Tamman–Fulcher (VTF) behavior which implies the coupling of the charge carriers with the segmental motion of the polymer chains. A maximum proton conductivity of 1.8×10−3 S/cm was obtained for the sample Si-ATetTA1 in anhydrous condition. [Copyright &y& Elsevier]

The synthesis and thermal as well as proton conducting properties of complex polymer electrolytes based on poly(2-acrylamido-2-methyl-1-propanesulfonic acid) PAMPS and poly(1-vinyl-1,2,4-triazole) PVTri were investigated. The materials were produced by complexation of PAMPS with PVTri at various compositions to get PVTriP(AMPS) where x is the molar ratio of the polymer repeating units and varied from 0.25 to 4. The structure of the materials was confirmed by FT-IR spectroscopy. The TGA results verified that the polymer electrolytes are thermally stable up to approximately 200 °C. The DSC and SEM results demonstrated the homogeneity of the materials. The electrochemical stability of the materials was studied by cyclic voltammeter (CV). Proton conductivity, activation energy, and water/methanol uptake of these membranes were also measured. After humidification (RH = 50%), PVTriP(AMPS) and PVTriP(AMPS) showed proton conductivities of 0.30 and 0.06 S/cm at 100 °C, respectively. [ABSTRACT FROM AUTHOR]

Abstract: In this work, poly(4-vinylbenzeneboronic acid), PVBBA was synthesized via free-radical polymerization of 4-vinylbenzeneboronic acid (4-VBBA) and followed by modification with polyethylene glycol monomethylether (PEGME) with different molecular weights to produce boron containing comb-branched copolymers and abbreviated as PVBBAPEGMEX. Then copolymer electrolytes were successfully prepared by doping of the host matrix with CF3SO3Li at several stoichiometric ratios to get PVBBAPEGMEX-Y (X is the molecular weight of PEGME and Y is the EO/Li ratio). The materials were characterized by using Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (1H-NMR and 11B-NMR), thermogravimetry (TG) and differential scanning calorimeter (DSC). The ionic conductivity of these novel copolymer electrolytes was studied by dielectric-impedance spectroscopy. Li-ion conductivity of these copolymer electrolytes depends on the length of the side units as well as the doping ratio. Such electrolytes possess satisfactory ambient temperature ionic conductivity (exceeding 10−4 S/cm) and good mechanical strength. At higher doping ratios, Vogel–Tamman–Fulcher (VTF) behavior of conductivity implies the coupling of the charge carriers with the segmental motion of the polymer chains. [Copyright &y& Elsevier]

Polymer electrolyte membranes were fabricated by blending of poly(2,5-benzimidazole) (ABPBI) and poly(styrene sulfonic acid) (PSSA) at several molar ratios with respect to repeating units. Fourier transform infrared spectroscopy was used to elucidate inter-polymer interactions. Surface morphology was studied through scanning electron microscope. Thermal properties of the membranes were investigated by thermogravimetric analysis and differential scanning calorimetry. The spectroscopic measurements and water uptake (WU) studies indicate a complexation between ABPBI and PSSA where the swelling behavior of membranes increases with the PSSA content. Proton conductivities of the anhydrous and humidified samples were measured using impedance spectroscopy. Proton conductivity of ABPBI:PSSA bend with (1:4) molar ratio was detected as around 10−3 S/cm at higher temperatures under anhydrous conditions. On the other hand, the membrane ABPBI:PSSA (1:2) showed the proton conductivity of 0.02 S/cm (ambient temperature, RH = 50%) which is at least five-order of magnitude higher than the anhydrous material. [ABSTRACT FROM AUTHOR]

A class of polymer electrolyte membranes was produced by the combination of poly( 1-vinyl-I 2,4 triazole) (PVTri) and poly(styrene sulfonic acid) (PSSA) at several stoichiometric ratios with respect to the molar ratio of polymer repeating units. PVTri was synthesized by free-radical polymerization of the monomer, 1-vinyl-1,2,4-triazole, and PSSA was produced from polystyrene by direct sulfonation. The proton-exchange reaction, which resulted in complexation between polymers, was illustrated by Fourier transform infrared spectroscopy. Thermogravimetric analysis showed that the membranes are thermally stable up to approximately 250°C. The existence of single glass-transition temperatures of the polymer electrolytes was shown by differential scanning calorimetry. The scanning electron microscopy results also demonstrated the homogeneity of the materials. The electrochemical stability of the materials was studied by cyclic voltammetry. Proton conductivities of the anhydrous samples were measured using impedance spectroscopy. Under an anhydrous State, maximum proton conductivities of PVTriP(SSA)4 and PVTriP(SSA)2 membranes were measured as 0.015 at 150°C and 0.033 S/cm at 120°C, respectively. [ABSTRACT FROM AUTHOR]

Abstract: The fabrication, thermal and proton conducting properties of complex polymer electrolytes based on poly(vinylphosphonic acid) (VPA) and poly(1-vinyl-1,2,4-triazole) (PVTri) were investigated throughout this work. The membrane materials were produced by complexation of PVPA with PVTri at various concentrations to get PVTriP(VPA) x where x designates the molar ratio of the polymer repeating units and varied from 0.25 to 4. The complexed structure of the polymers was confirmed by FT-IR spectroscopy. The TGA results verified that the presence of PVTri in the complex polymer electrolytes suppressed the formation of phosphonic acid anhydrides up to 150°C. The DSC and SEM results demonstrated the homogeneity of the materials. Proton conductivity, activation energy and water/methanol uptake of these membranes were also measured. PVTriP(VPA)2 showed a proton conductivity of 2.5×10−5 Scm−1 at 180°C in the anhydrous state. After humidification (RH=50%), PVTri-P(VPA)4 and PVTri-P(VPA)2 showed respective proton conductivities of 0.008 and 0.022Scm−1 at 100°C, where the conductivity of the latter is close to Nafion 117 at the same humidity level. [Copyright &y& Elsevier]

In this study, proton conducting polymer electrolyte networks consisting of alginic acid (AA) and poly(1-vinylimidazole) (PVI) were prepared. The polymer networks were obtained by mixing AA and PVI with several stoichiometric ratios, x (with respect to monomers). Polymer networks were characterized by ET-IR spectroscopy and their compositions were investigated by elemental analysis (EA). Enzyme entrapped polymer networks (EEPN) were produced by immobilization of tyrosinase in the AA/PVI matrix during complexation. The maximum reaction rate (Vmax) and Michaelis-Menten constant (Km) were investigated for the immobilized tyrosinase. Also, the temperature and pH optimizations, operational stability and shelf life of enzyme immobilized in the polymer network were examined. [ABSTRACT FROM AUTHOR]

Sulfonated hollow silica spheres (HSS‐S) are synthesized and applied in supercapacitors as acid‐filling and acid‐releasing agents in a polymer matrix, thanks to their unique architecture wherein the hollow spheres can be filled with acid (HSS‐S‐F) and can be dispersed in poly(vinyl alcohol) (PVA) with various weight fractions to produce nanocomposite gel polymer electrolytes (GPEs), HSS‐S/PVA, and HSS‐S‐F/PVA. The symmetrical supercapacitor device is assembled using an active carbon(AC) electrode and the GPE HSS‐S‐F/PVA shows a specific capacitance value of 147 F g−1 at 0.5 A g−1. Alternatively, the GPE HSS‐S/PVA shows a specific capacitance of 52 F g−1 at the same current density. The symmetrical supercapacitor based on HSS‐S‐F/PVA has a high‐energy density of 20.40 W·h kg−1 at a power density of 545 W kg−1 with a remarkable cyclic stability with a loss of only 15% after 2250 charge–discharge cycles. This excellent property demonstrates that HSS‐S is a promising additive and has the potential to produce more efficient energy storage devices by changing the hollow particle size, pore size, and using different host polymer electrolytes. [ABSTRACT FROM AUTHOR]

In this work, a series of novel lithium ion‐conducting copolymer electrolytes based on 2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid (AMPS) and poly(ethyleneglycol) methacrylate (PEGMA) were produced and characterized. The copolymers were synthesized by free‐radical polymerization of the corresponding monomers with three different feed ratios to form P(AMPS‐co‐PEGMA)‐based electrolytes. After the polymerization, AMPS units of the copolymers were lithiated via ion exchange. The characterization of the electrolytes was done by 1H‐NMR, FTIR, differential scanning calorimetry (DSC), thermogravimetric analysis, X‐ray diffraction, scanning electron microscopy (SEM), and impedance analyzer. The copolymers were thermal stable approximately to 200 °C. Single Tg transitions in DSC curves verified the homogeneity as well as amorphous characteristics. SEM further confirmed the homogeneity of the electrolytes. The lithium ion conductivity of these new polymer electrolytes was studied by impedance dielectric impedance analyzer and the effect of PEGMA contents onto the ionic conductivity of these copolymer electrolytes were investigated. It was observed that the temperature dependence of ionic conductivity was interpreted over Vogel Tammann Fulcher model. The Li ion conductivity increased by PEGMA content and S3 has maximum conductivity of 3 × 10−3 mS cm−1 at 100 °C. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47798. [ABSTRACT FROM AUTHOR]

Abstract: Polymer electrolyte membranes (PEM) were fabricated by blending of Poly(2,5-benzimidazole) (ABPBI) and Poly(vinylphosphonic acid) (PVPA) at several stoichiometric ratios with respect to monomer repeating units. The characterization of the membranes were carried out by using Fourier-transform infrared spectroscopy (FT-IR) for inter-polymer interactions, scanning electron microscope (SEM) for surface morphology as well as homogeneity and thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) for thermal properties. Water uptake measurements were made to investigate the swelling character the blends that was changed with PVPA composition. The spectroscopic measurements and water uptake studies suggested the complexation between ABPBI and PVPA that inhibited dopant exclusion up on swelling in excess water. Proton conductivities of the hydrated and anhydrous samples were measured using impedance spectroscopy. Although the proton conductivity of the blends was lower in the anhydrous state such as 1.8×10−6 S/cm at 150°C for ABPBI:PVPA with (1:2), it increased to 0.004S/cm for ABPBI:PVPA (1:4) at 20°C (RH=50%). [Copyright &y& Elsevier]

Abstract: Polymer electrolyte composite membranes based on poly(1-vinyl-1,2,4-triazole) (PVTRI) and nitrilotri(methyl triphosphonic acid) (TPA) were investigated. PVTRI was produced by free radical polymerization of 1-vinyl-1,2,4-triazole. The polymer PVTRI was doped with TPA at various molar ratios x=0.125, x=0.25, and x=0.5. The proton transfer from TPA to the triazole rings was proved with Fourier-transform infrared spectroscopy (FT-IR). Thermogravimetry (TG) analysis showed that the samples are thermally stable up to approximately 250°C. DSC results illustrated the homogeneity of the materials as well as the softening effect of the dopant. Cyclic voltammetry results illustrated that the electrochemical stability domain of the dopant extends over 1.5V. The maximum proton conductivity has been measured for PVTRITPA-0.25 as 8.5×10−4 S cm−1 at 150°C. [Copyright &y& Elsevier]

Abstract: In the present work, proton conductivity in a polymer blend comprising proton solvating heterocycles was examined. Poly(1-vinyl-1,2,4-triazole), PVTri was produced by free radical polymerization of 1-vinyl-1,2,4-triazole and then proton-conducting polymer electrolytes were obtained by blending of PVTri with trifluoromethanesulfonic acid, triflic acid (TA). To promote the intrinsic proton conductivity the percent blending ratio was changed from 25% to 150% with respect to polymer repeat unit. The protonation of aromatic heterocyclic rings was proved with Fourier-transform infrared spectroscopy (FT-IR). Thermogravimetry (TG) analysis showed that the samples are thermally stable up to approximately 300°C. Differential scanning calorimetry (DSC) results illustrated that the samples are homogeneous and their glass transition temperatures are located within 130–160°C. The surface morphology of the materials were characterized by scanning electron microscopy (SEM). The proton conductivity of the blends increased with triflic acid concentration and the temperature. In the anhydrous state, the proton conductivity of PVTriTA100 is 2.2×10−4 S/cm at 150°C and that of PVTriTA150 is approximately 0.012S/cm at 80°C which is similar to that of hydrated Nafion®. [Copyright &y& Elsevier]

In this study, a new type of graft copolymer based on polyethylene glycol monomethyl ether (PEGME) grafted poly(vinyl alcohol-co-acrylonitrile) (poly(VA-co-AN)) was produced. The synthesis of the copolymer was certified by spectroscopic techniques, and then the gel polymer electrolytes (GPEs) were acquired by doping with LiBF 4 at various mass ratios. The polymer electrolytes indicated promising thermal stabilities up to 220 °C and obtained amorphous nature after grafting. Moreover, the insertion of PEGME side chains softened the materials and improved the ionic conductivity. The polymer electrolyte, PE (poly(VA-co-AN)/PEGME/XH 3 BO 3 /YLiBF 4 X, Y; 10, 5 in moles), illustrated high conductivity at ambient temperature. The electrochemical capacitor device fabricated with GPE3 electrolyte yielded a specific capacitance of 105 F g−1 at a specific current of 1 A g−1. The specific density of 14.8 Wh kg−1 was obtained from the same device at a specific power of 5000 W kg−1. Excellent cyclic stability with a high coulombic efficiency of 90% was observed after 30 days of consecutive measurements at a specific current of 1 mA g−1. • A new type of graft copolymer based on PEGME grafted poly(VA-co-AN) was synthesized. • GPEs were produced by doping with LiBF 4 at various mass ratios. • Supercapacitor device with GPE yielded a remarkable specific capacitance of 105 F g−1. • Energy density of 14.8 Wh kg−1 was obtained at a power density of 5000 W kg−1. • Excellent cyclic stability with high coulombic efficiency of 90% observed after 30 days. [ABSTRACT FROM AUTHOR]