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1.
Side‐chain‐type sulfonated/quaternized aromatic polyelectrolytes with precisely controlled contents of ionized groups are successfully synthesized via direct polyacylation of sulfonated/quaternized monomers based on 2,2′‐dihydroxy‐1,1′‐binaphthyl (DHBN). Both proton exchange membranes (PEMs) and anion exchange membranes (AEMs) of the corresponding polyelectrolytes exhibit outstanding properties. Proton conductivity (116 mS cm?1 at 30 °C) higher than Nafion 115 for the PEMs and OH– conductivity (28.5–53.7 mS cm?1 at 30 °C) comparable to Tokuyama A901 for the AEMs are accomplished. In addition, the AEMs can withstand 60 days’ aging in 1 mol L?1 NaOH at 60 °C without degradation, as proved by 1H NMR. More intriguingly, when starting from optically active (S)‐DHBN instead of racemic DHBN, an enhancement in proton conductivity of PEMs is observed for the first time, which opens a new door to optically active ion exchange membranes. 相似文献
2.
Quaternized polysulfone‐based nanocomposite membranes and improved properties by intercalated layered double hydroxide
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Na Liang Wan Liu Danying Zuo Pai Peng Rong Qu Dongzhi Chen Hongwei Zhang 《Polymer Engineering and Science》2018,58(5):767-774
Two anions (dodecylbenzenesulfonate anion and stearate anion) are employed to synthesize intercalated layered double hydroxides (LDH) by co‐precipitation method. Then the intercalated LDHs are incorporated in the casting solutions of chloromethylated polysulfone (CMPSF) for fabricating quaternized polysulfone/LDH nanocomposite membranes. Fourier transform infrared, X‐ray diffraction, thermogravimetric analysis, scanning electron microscopy, and mastersizer laser particle size analysis are used to characterize the structure and morphology of LDHs and membranes. The properties of the composite membranes including water uptake, mechanical property, thermal stability, and ionic conductivity are investigated. Compared with other anion exchange membranes, both nanocomposite membranes containing 5% LDH sheets displayed better balanced performance. They exhibit the ionic conductivity of 3.58 × 10?2 S cm?1 and 3.86 × 10?2 S cm?1 at 60°C, respectively. POLYM. ENG. SCI., 2017. © 2017 Society of Plastics Engineers 相似文献
3.
Md. Awlad Hossain Youngdon Lim Soonho Lee Hohyoun Jang Seongyoung Choi Taehoon Hong Lei Jin Whan Gi Kim 《Reactive and Functional Polymers》2013,73(9):1299-1305
Anion exchange membranes of poly(fluorenylene ether sulfone) containing imidazolium hydroxide-functionalized fluorenyl groups were synthesized by sequential polycondensation, chloromethylation, substitution with imidazolium and ion exchange. They showed elevated molecular weight, high solubility in polar aprotic solvents and strong chemically and thermally stability in comparison to alkyl quaternary ammonium-functionalized polymers. Different levels of substitution and ion exchange were tested; the resulting ionomer membranes showed high ion exchange capacities (IECs) of up to 1.96 mmol g?1. The imidazolium-functionalized copolymer membranes showed lower water affinity and excellent chemical stability in alkaline conditions. They exhibited hydroxide conductivity above 10?2 S cm?1 at room temperature and outstanding chemical stability for up to 7 days without significant losses of ion conductivity. 相似文献
4.
A series of free‐standing hybrid anion‐exchange membranes were prepared by blending brominated poly(2,6‐dimethyl‐1,4‐phenylene oxide) (BPPO) with poly(vinylbenzyl chloride‐co‐γ‐methacryloxypropyl trimethoxy silane) (poly(VBC‐co‐γ‐MPS)). Apart from a good compatibility between organic and inorganic phases, the hybrid membranes had a water uptake of 32.4–51.8%, tensile strength around 30 MPa, and Td temperature at 5% weight loss around 243–261°C. As compared with the membrane prepared from poly (VBC‐co‐γ‐MPS), the hybrid membranes exhibited much better flexibility, and larger ion‐exchange capacity (2.19–2.27 mmol g?1) and hydroxyl (OH?) conductivity (0.0067–0.012 S cm?1). In particular, the hybrid membranes with 60–75 wt % BPPO had the optimum water uptake, miscibility between components, and OH? conductivity, and were promising for application in fuel cells. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
5.
A novel way for anion exchange membrane (AEM) preparation has been investigated, avoiding the use of expensive and toxic chemicals. This new synthetic approach to prepare AEMs was based on the use of a porous polybenzylimidazole membrane as support in which functionalized ILs were introduced and subsequently grafted on the polymer backbone. These new AEMs were prepared and their chemical structures and properties including morphology, thermal stability, and ionic conductivity were characterized. The hydroxyl ionic conductivity of the synthesized membranes can reach values upto 6.62 × 10?3 S cm?1 at 20°C. Although the ionic conductivity is not very high yet, the work shows the strength of the concept. Membrane properties can be easily tailored toward specific applications by choosing the proper chemistry, i.e., porous polymer support, ionic liquid, and method of initiation and polymerization. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
6.
Quaternary ammonium functionalized poly(arylene ether)s (QPAEs) containing 2,2′,6,6′‐tetramethylbiphenol moieties were designed and successfully synthesized via nucleophilic substitution polycondensation, bromination, quaternization and alkalization. The structure, water uptake, ion exchange capacities (IECs), hydroxide ion conductivities, and mechanical properties, as well as thermal and chemical stabilities of obtained QPAEs membranes were investigated. The QPAE‐a membrane with IEC value of 0.98 meq g?1 demonstrated the highest ion conductivity (47.4 mS cm?1) at 80°C. The ion transport activation energy (Ea) of QPAEs membranes varied from 8.57 to 19.95 kJ mol?1. After chemical stability test conditioned in 1M NaOH at 60°C for 7 days, the QPAEs membranes except QPAE‐c (IEC = 0.88 meq g?1) still exhibited high hydroxide ion conductivities (over 15 mS cm?1) and acceptable tensile strength (~10 MPa). These properties indicate that the ionomers membranes are potential candidates for anion exchange membranes in anion exchange membrane fuel cells. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41525. 相似文献
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8.
Preparation and properties of alkaline anion exchange membrane with semi‐interpenetrating polymer networks based on poly(vinylidene fluoride‐co‐hexafluoropropylene)
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Alkaline anion exchange membrane with semi‐interpenetrating polymer network (s‐IPN) was constituted based upon quaternized poly(butyl acrylate‐co‐vinylbenzyl chloride) (QPBV) and poly(vinylidene fluoride‐co‐hexafluoropropylene) [P(VDF‐HFP)]. The QPBV was synthesized via the free radical copolymerization, followed by quaternization with N‐methylimidazole. The s‐IPN system was constituted by melting blend of QPBV and P(VDF‐HFP), and then crosslinking of P(VDF‐HFP). Ion exchange capacity, water uptake, mechanical performance, and thermal stability of these membranes were characterized. TEM showed that alkaline anion exchange membrane exhibited s‐IPN morphology with microphase separation. The fabricated s‐IPN membrane exhibited hydroxide ion conductivity up to 15 mS cm?1 at 25 °C and a maximum DMFC power density of 46.55 mW cm?2 at a load current density of 98 mA cm?2 at 30 °C. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45775. 相似文献
9.
Polystyrene‐based anion exchange membranes via click chemistry: improved properties and AEM performance
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Sayema K Tuli Asa L Roy Ramez A Elgammal Thomas A Zawodzinski Tomoko Fujiwara 《Polymer International》2018,67(9):1302-1312
Polystyrene‐based anion exchange membranes (AEMs) have been fabricated using in situ click chemistry between azide and alkyne moieties introduced as side groups on functionalized polymers. The membrane properties such as water uptake, swelling ratio and conductivity were affected by the number of cations and the degree of crosslinking. The membranes containing a larger amount of trimethylammonium cationic groups (i.e. higher ion exchange capacity) showed high hydroxide conductivity when immersed in KOH solution, exhibiting a peak in conductivity (156 mS cm?1) in 3 mol L–1 KOH solution. A higher degree of crosslinking tended to decrease conductivity. These membranes demonstrated relatively good stability in 8 mol L–1 KOH at 60 °C and maintained 33%–62% of initial conductivity after 49 days with most of the loss in conductivity occurring in early stages of the test. In an alkaline fuel cell, the areal specific resistance was constant indicating good stability of the membranes. The observed peak power density (157 mW cm?2) was comparable to that of other AEM‐based fuel cells reported. © 2018 Society of Chemical Industry 相似文献
10.
Mingtao Li Li Yang Shaohua Fang Siming Dong Shin‐ichi Hirano Kazuhiro Tachibana 《Polymer International》2012,61(2):259-264
Polymerized ionic liquids (PILs) having guanidinium cations with different counter‐anions, such as PF6? and N(CF3SO2)2? (TFSI?), were synthesized by copolymerization of a guanidinium ionic liquid monomer with methyl acrylate followed by an anion exchange reaction. Furthermore, incorporating a guanidinium ionic liquid, LiTFSI salt and nano‐size SiO2, a quaternary gel polymer electrolyte based on one of the PILs as the polymer host was prepared. The quaternary gel polymer electrolyte was chemically stable even at a higher temperature of 80 °C in contact with the lithium anode. In particular, the electrolyte exhibited high lithium ion conductivity, wide electrochemical stability window and good lithium stripping/plating performance. Li/LiFePO4 batteries with the quaternary gel polymer electrolyte at 80 °C had capacities of 140 and 130 mA h g?1 respectively at 0.1 and 0.2 C current rates. Copyright © 2011 Society of Chemical Industry 相似文献
11.
Preparation of anion exchange membrane based on homogeneous quaternization of bromomethylated poly(arylene ether sulfone)
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This article presented the synthetic and preparation route of quaternary ammonium functionalized anion exchange membranes (AEMs), which were derived from an engineering plastics polymer, poly(arylene ether sulfone) with 3,3′,5,5′‐tetramethyl‐4,4′‐dihydroxybipheny moiety (PAES‐TM). The benzylmethyl groups on the main‐chain of PAES‐TM were converted to the bromomethyl groups via a radical reaction, thereby avoiding complicated chloromethylation, which required carcinogenic reagents. The chemical structure of the bromomethylated PAES was characterized by 1H NMR spectrum. Following a homogeneous quaternization with trimethylamine in the solution, a series of flexible and tough membranes were obtained by a solution casting and anion exchange process. The ion exchange capacity values were ranging from 1.03 to 1.37 meq g?1. The properties of the membranes, including water uptake, hydroxide conductivity, and methanol permeability were evaluated in detail. The AEM showed a high conductivity above 10?2 S cm?1 at room temperature and extremely low methanol permeability of 4.16–4.94 × 10?8 cm2 s?1. The high hydroxide conductivity of TMPAES‐140‐NOH could be attributed to the nano‐scale phase‐separated morphology in the membrane, which was confirmed by their transmission electron microscopy images. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40256. 相似文献
12.
Tongwen Xu Dan Wu Seok‐Jun Seo Jung‐Je Woo Liang Wu Seung‐Hyeon Moon 《应用聚合物科学杂志》2012,124(4):3511-3519
New composite proton exchange membrane was prepared by mixing a 1‐methyl‐2‐pyrrolidone (NMP) solution of sulfonated poly(2,6‐dimethyl‐1,4‐phenylene oxide) (SPPO) in sodium form and brominated poly(2,6‐dimethyl‐1,4‐phenylene oxide) (BPPO) for hydrophilic‐hydrophobic balance, then casting the solution as a thin film, evaporating the solvent, and treating the membrane with aqueous hydrochloric acid. The resulting membranes were subsequently characterized using FTIR‐ATR, SEM‐EDXA, and TGA instrumentation as well as measurements of basic properties such as ion exchange capacity (IEC), water uptake, proton conductivity, methanol permeability, and single cell performance. Water uptake, IEC, proton conductivity, and methanol permeability all increased with a corresponding increase of SPPO content. By properly compromising the conductivity and methanol permeability, membranes with 60–80 wt % SPPO content exhibited comparable proton conductivity to that of Nafion® 117, with only half the methanol permeability, thereby demonstrating higher single cell performance. The membranes developed in this study could thus be a suitable candidate electrolyte for proton exchange membrane fuel cells (PEMFCs). © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
13.
Rakhi Sood Mona Marie Obadia Bhanu Prakash Mudraboyina Biao Zhang Anatoli Serghei Julien Bernard Eric Drockenmuller 《Polymer》2014
Nitroxide-mediated radical polymerization of a tailor-made acrylate carrying a 1,2,3-triazole group with an undecanoyl spacer affords a well-defined (Mn = 7860 g mol−1 and D = 1.39) neutral polyacrylate precursor. A series of 1,2,3-triazolium-based poly(ionic liquid)s (TPILs) is then obtained by straightforward quaternization of the 1,2,3-triazole groups with methyl iodide and subsequent anion metathesis reactions. Among the prepared materials, TPIL with bis(trifluoromethane)sulfonimide anion exhibits low glass transition temperature (Tg = −40 °C), high thermal stability (Td10 = 325 °C) and anhydrous ionic conductivity of 4 × 10−6 S cm−1 at 30 °C, as measured by differential scanning calorimetry, thermogravimetric analysis and broadband dielectric spectroscopy, respectively. 相似文献
14.
A series of novel sulfonated polyimide (SPI)/crosslinked poly(N‐isopropylacrylamide) (cPNIPAm) semi‐interpenetrating polymer networks (semi‐IPNs) were synthesized as the proton exchange membranes for direct methanol fuel cells via in situ polymerization. The micromorphology and properties of the semi‐IPN membranes were characterized. The results indicated that the hydrogen bonds between cPNIPAm and SPI in the semi‐IPN structure were a crucial factor for regulating the micromorphology, proton conductivity and other properties of the semi‐IPN membranes. A more uniform sulfonic ionic cluster distribution was observed in the membrane of SPI‐20‐cPNIPAm with equimolar ratio of sulfonic acid groups and amido bonds, which could provide effective proton transport channels. The SPI‐20‐cPNIPAm exhibited a maximum proton conductivity of 0.331 S cm?1 at 80 oC (relative humidity 100%), an optimal selectivity of 8.01 × 105 S s cm?3 and an improved fuel cell performance of 72 mW cm?2 compared with both pristine SPI and other semi‐IPN membranes. The SPI‐20‐cPNIPAm semi‐IPN membranes also retained good mechanical properties and thermal stabilities on the whole. © 2014 Society of Chemical Industry 相似文献
15.
Controllable Cross‐Linking Anion Exchange Membranes with Excellent Mechanical and Thermal Properties
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Chao Wang Zhenfeng He Xiaofeng Xie Xianmin Mai Yingchun Li Tingxi Li Min Zhao Chao Yan Hu Liu Evan K. Wujcik Zhanhu Guo 《大分子材料与工程》2018,303(3)
A new monomer called 2,2′‐(4,4′‐oxydiphenol‐4,4′‐diyl)bis(2‐methyl‐2,3,3a,4,7,7a‐hexahydro‐1H‐4,7‐methanoisoindol‐2‐ium) iodide (d3) is synthesized possessing both cross‐linker and functional groups. The membranes are formed by copolymerizing d3 with norbornene and (3aR,4S,7R,7aS)‐2‐methyl‐2‐(3‐(trimethylammonio)propyl)‐2,3,3a,4,7,7a‐hexahydro‐1H‐4,7‐methanoisoindol‐2‐ium iodide (a3) at varying ratios. The water uptake is 41.35% at 60 °C, and ion exchange capacity is 2.35 mequiv g?1 for a mole ratio of a3, norbornene, and d3 (1:6:3). The conductivity is 12, 37, and 40 mS cm?1 when d3 is decreased. Meanwhile, the conductivity increases quickly with increasing the temperature. Furthermore, the mechanical properties and thermal properties are improved, attributed to the increased cross‐linker. The membrane has a tensile strength of 41.3 MPa and the elongation at break of 38.0 %, and the 5 wt% loss temperature for membrane is ≈159 °C. The H2/O2 single fuel cells with this membrane show a maximum power density of 124 mW cm?2 at 50 °C. The cross‐linked membranes demonstrate high‐dimensional stability in alkaline solution. 相似文献
16.
Conductive imidazolium side chain liquid crystal polyacrylates prepared from postpolymerization functionalization
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Hydroxide and tetrafluoroborate salts of imidazolium polyacrylates have been prepared from postpolymerization functionalization of a brominated precursor containing mesogenic side chains followed by anion exchange. The ionic polyacrylates possessed molecular weights in the range 1.1–1.3 × 104 g·mol?1. Differential scanning calorimetry measurements and polarizing optical microscope observation indicated that the resultant ionic polyacrylates exhibited smectic C and A liquid crystal phases over a temperature range of about 60°C. Electrochemical impedance spectroscopy measurements show that ionic conductivities of the hydroxide salt were much higher than those of the tetrafluoroborate salt for the imidazolium polyacrylates at the same temperature. The maximum ionic conductivity of the random hydroxide salt of imidazolium polyacrylate in the smectic A phase reached 4.45 × 10?2 S·cm?1. The ionic polyacrylates were successfully aligned by mechanical shearing in the smectic A phase. Ionic conductivities of the sheared samples were more than 1 order of magnitude higher than those of the random samples in the solid state. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41564. 相似文献
17.
A series of phenolphthalein-based cardo poly(arylene ether sulfone) (PES) block copolymers containing pendant imidazolium group (PI-PESs) were synthesized as novel anion exchange membranes for direct methanol alkaline fuel cells. These PI-PESs combine the advantages of pendant anion conductors on the polymer side chains with the thermochemical stabilities of the imidazolium group, showing high hydroxide conductivity, together with good physical and chemical stability under basic conditions. The hydroxide conductivity over 0.03 S/cm at 20 °C and 0.1 S/cm at 80 °C was obtained for the PI-PES membranes. In addition, PI-PES membranes show low permeability to methanol (below 6.74 × 10−8 cm2/s) and very high selectivity (over 3.7 × 105 S·s/cm3). These properties make the PI-PESs promising candidate materials for anion exchange membranes for direct methanol alkaline fuel cells. 相似文献
18.
A series of poly(arylene ether)s with biphenyl units and pendant sulfonated phenylsulfonyl groups was prepared via nucleophilic aromatic substitution reactions of varying ratios of 3,5‐difluoro‐3′‐sulfonated diphenylsulfone and 4,4′‐difluorodiphenylsulfone with 4,4′‐biphenol. As such, the sulfonic acid moieties reside in the meta position of a pendant, electron‐poor phenylsulfonyl group. Mechanically robust proton‐exchange membranes with ion‐exchange capacities (IEC) ranging from 0.91 to 2.05 meq g?1 were cast from dimethylacetamide. The thermal stability of the membranes was evaluated via thermogravimetric analysis and the 5% weight losses were found to be in excess of 330 °C in air. The glass transition temperatures were determined, via differential scanning calorimetry, to range from a low of 148 to a high of 209 °C at IEC values of 0.91 and 1.79 meq g?1, respectively. The copolymer membranes reached proton conductivities as high as 142 mS cm?1 under 100% relative humidity, with relatively low water uptake values (8–32 wt%). Copyright © 2012 Society of Chemical Industry 相似文献
19.
Novel single‐ion conducting polymer electrolytes based on electrospun poly(lithium 2‐acrylamido‐2‐methylpropanesulfonic acid) (PAMPSLi) membranes were prepared for lithium‐ion batteries. The preparation started with the synthesis of polymeric lithium salt PAMPSLi by free‐radical polymerization of 2‐acrylamido‐2‐methylpropanesulfonic acid, followed by ion‐exchange of H+ with Li+. Then, the electrospun PAMPSLi membranes were prepared by electrospinning technology, and the resultant PAMPSLi fiber‐based polymer electrolytes were fabricated by immersing the electrospun membranes into a plasticizer composed of ethylene carbonate and dimethyl carbonate. PAMPSLi exhibited high thermal stability and its decomposition did not occur until 304°C. The specific surface area of the electrospun PAMPSLi membranes was raised from 9.9 m2/g to 19.5 m2/g by varying the solvent composition of polymer solutions. The ionic conductivity of the resultant PAMPSLi fiber‐based polymer electrolytes at 20°C increased from 0.815 × 10?5 S/cm to 2.12 × 10?5 S/cm with the increase of the specific surface area. The polymer electrolytes exhibited good dimensional stability and electrochemical stability up to 4.4 V vs. Li+/Li. These results show that the PAMPSLi fiber‐based polymer electrolytes are promising materials for lithium‐ion batteries. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
20.
Modified carbon nanotubes (m‐CNTs) were successfully prepared by the interactions between nitric and sulfuric acids and CNTs, which was confirmed using Fourier transform infrared spectroscopy. Poly[(vinylidene fluoride)‐co‐hexafluoropropylene]‐based composite polymer electrolyte (CPE) membranes doped with various amounts of m‐CNTs were prepared by phase inversion method. The desired CPEs were obtained by soaking the liquid electrolytes for 30 min. The physicochemical and electrochemical properties of the CPE membranes were investigated using scanning electron microscopy, X‐ray diffraction, thermogravimetry, electrochemical impedance spectroscopy and linear sweep voltammetry. The results show that the CPE membranes doped with 2.2 wt% m‐CNTs possess the smoothest surface and the highest decomposition temperature about 450 °C. Obviously, adding an appropriate amount of m‐CNTs into the polymer matrix can decrease the crystallinity and enhance the ionic conductivity; the temperature dependence of ionic conductivity follows the Arrhenius relation and the ionic conductivity at room temperature is up to 4.9 mS cm?1. The interfacial resistance can reach a stable value of about 415 Ω cm?2 after 10 days storage. The excellent rate and cycle performances with an electrochemical working window up to 5.4 V ensure that the CPEs doped with 2.2 wt% m‐CNTs can be considered as potential candidates as polymer electrolyte for lithium ion batteries. © 2013 Society of Chemical Industry 相似文献