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1.
The gel polymer electrolytes composed of ionic liquid, 1‐butyl‐3‐methylimidazolium tetrafluoroborate (BMImBF4) and the copolymer of acrylonitrile (AN), methyl methacrylate (MMA), poly(ethylene glycol) methyl ether methacrylate (PEGMEMA) are synthesized and characterized by FT‐IR spectra, TGA, DSC, and AC impedance measurements. IR spectra show that there is an interaction between PEO side chains of the copolymer and imidazolium cations. TGA measurements indicate that the gel polymer electrolytes are stable until 120°C. By using the equivalent circuit proposed, the experimental data and the simulated data fit very well. The bulk resistance Rb is found to decrease with the increase in BMImBF4 content. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
2.
Palladium nanoparticles stabilized by an ionic polymer and ionic liquid: a versatile system for C-C cross-coupling reactions 总被引:1,自引:0,他引:1
Highly stable palladium nanoparticles (Pd NPs), protected by an imidazolium-based ionic polymer (IP) in a functionalized ionic liquid (IL), have been prepared and characterized by transmission electron microscopy (TEM). These Pd NPs are excellent precatalysts for Suzuki, Heck, and Stille coupling reactions and can be stored without undergoing degradation for at least 2 years. The NP-IP-IL system may therefore be considered as an alternative to the traditional palladium on carbon (Pd/C) precatalyst employed in many C-C coupling reactions, also allowing reactions to be conducted under "solvent-free" conditions. 相似文献
3.
Tomohiro Ogawa Kazuki Takahashi Sanjog S. Nagarkar Koji Ohara You-lee Hong Yusuke Nishiyama Satoshi Horike 《Chemical science》2020,11(20):5175
High proton conducting electrolytes with mechanical moldability are a key material for energy devices. We propose an approach for creating a coordination polymer (CP) glass from a protic ionic liquid for a solid-state anhydrous proton conductor. A protic ionic liquid (dema)(H2PO4), with components which also act as bridging ligands, was applied to construct a CP glass (dema)0.35[Zn(H2PO4)2.35(H3PO4)0.65]. The structural analysis revealed that large Zn–H2PO4−/H3PO4 coordination networks formed in the CP glass. The network formation results in enhancement of the properties of proton conductivity and viscoelasticity. High anhydrous proton conductivity (σ = 13.3 mS cm−1 at 120 °C) and a high transport number of the proton (0.94) were achieved by the coordination networks. A fuel cell with this CP glass membrane exhibits a high open-circuit voltage and power density (0.15 W cm−2) under dry conditions at 120 °C due to the conducting properties and mechanical properties of the CP glass.A proton-conducting coordination polymer glass derived from a protic ionic liquid works as a moldable solid electrolyte and the anhydrous fuel cell showed I–V performance of 0.15 W cm−2 at 120 °C. 相似文献
4.
Polymerizable ionic liquids and their actuation in an electric field are a combination of material and properties with unique potential to display structural and fluid dynamics above that found in small molecule ionic liquids. In an effort to blend ionic liquid nature with actuation response, we have synthesized a new ionic liquid ammonium sulfonate monomer and polymer. The liquid temperature ranges of both the monomer and polymer ionic liquid systems are quite large extending from their respective glass transitions (Tg) of -57 and -49 degrees C to decomposition at approximately 200 degrees C. Particularly remarkable is the small Tg increment that accompanies the transformation from monomer to polymer. The electrowetting behavior of the polymer and of the monomer presents an interesting contrast. This communication will encompass the polymerization, characterization, and actuation of these new ionic liquids. 相似文献
5.
Different types of columns with specific structural properties were used for the separation of mixtures of ionic liquid cations. Two of them were home-made packings and the other two were commercial stationary phases. One of the home-made packings contained cholesterol ligands bonded chemically to silica (SG-CHOL) whereas the other one was a mixed stationary phase (SG-MIX) with cyanopropyl, aminopropyl, phenyl, octyl, and octadecyl ligands. RP-18e Innovation ChromolithTM Performance and Macrosphere 300 C4 packings were also used. A comparison of the separation possibilities offered by these columns for the substances in question revealed significant differences in performance. Packings containing surface-bonded functional groups that are able to undergo protonation are not suitable for separation of such compounds under the given analysis conditions (pH = 4). The best results were obtained for two alkyl stationary phases: butyl and octadecyl. Cluster analysis has also been performed for comparison of the ionic liquid cation properties. 相似文献
6.
M. Kohoutová Š. Hovorka J. Schauer K. Setni?ková S. Guernik P. Izák 《European Polymer Journal》2009,45(3):813-39
Pervaporation was used for removal of butan-1-ol from its 5 wt.% of aqueous solution, at which the concentration of Clostridium acetobutylicum starts to decrease. The polydimethylsiloxane (PDMS) membrane containing 0, 10, 20 or 30 wt.% of benzyl-3-butylimidazolium tetrafluoroborate ([BBIM][BF4]) ionic liquid was used. Differential scanning calorimetry measurements showed that PDMS-[BBIM][BF4] membranes (though optically homogeneous) contained PDMS and [BBIM][BF4] phases. Pervaporation selectivity increased and total flux through membranes raised moderately with an increased content of [BBIM][BF4] in PDMS-[BBIM][BF4] membranes. Hence, immobilization of a proper ionic liquid in a membrane results in the creation of pervaporation membranes, effective in the removal of alcohol from fermentation broths. 相似文献
7.
Jun‐ichi Horinaka Ryosuke Yasuda Toshikazu Takigawa 《Journal of Polymer Science.Polymer Physics》2011,49(13):961-965
Concentrated solutions of cellulose and amylose were prepared with an ionic liquid 1‐butyl‐3‐methylimidazolium chloride (BmimCl), which was chosen as a good solvent for these polysaccharides. Dynamic viscoelasticity of the concentrated solutions was examined to obtain the molecular weight between entanglements, Me. The value of Me in the molten state (Me,melt), a material constant that reflecting the entanglement properties, was determined for cellulose and amylose by extrapolating Me to the “melt.” A marked difference in Me,melt was found: 3.2 × 103 for cellulose and 2.5 × 104 for amylose. The value of Me,melt for cellulose, which is composed of β‐(1,4) bonding of D ‐glucose units, is very close to those for polysaccharides with a random‐coil conformation such as agarose and gellan in BmimCl. The much larger Me,melt for amylose can be attributed to the helical nature of the amylose chain, α‐(1,4)‐linked D ‐glucose units. The effect of concentration on the zero‐shear viscosity for the solutions of cellulose and amylose was also examined. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011 相似文献
8.
Yoshizawa-Fujita M Kousa Y Kidena K Ohira A Takeoka Y Rikukawa M 《Physical chemistry chemical physics : PCCP》2011,13(29):13427-13432
An ionic liquid having a hydroxyl group, choline bis(trifluoromethylsulfonyl)amide ([N(111(2OH))][N(Tf)(2)]), was synthesized to investigate the effect of hydroxyl groups on the proton transport. 1,1,1-Trifluoro-N-(trifluoromethylsulfonyl)methanesulfoneamide (HN(Tf)(2)) as a proton source was mixed with the choline derivative at various molar ratios. Their thermal properties, viscosities, and ionic conductivities were investigated. [N(111(2OH))][N(Tf)(2)] showed a melting point at 27 °C, and its thermal stability was higher than 400 °C. The viscosity of [N(111(2OH))][N(Tf)(2)]/HN(Tf)(2) mixtures increased as the acid molar fraction increased. The ionic conductivity of [N(111(2OH))][N(Tf)(2)] was 2.1 × 10(-3) S cm(-1) at 25 °C; the ionic conductivity monotonously decreased as the acid molar fraction increased. There was a clear correlation between the ionic conductivity and the viscosity for the mixtures of the choline derivative and the acid. PFG-NMR measurements were carried out to investigate the diffusion behavior of protons. Although the acid and the hydroxyl group were indistinguishable by (1)H NMR, the self-diffusion coefficient of the (1)H of the hydroxyl group and the acid was larger than those of other (1)H nuclei. This difference suggests that a fast intermolecular proton transfer exists between the hydroxyl group and the acid. 相似文献
9.
Choi Jung-Weon Ryu Hayeon Oh Wonzin Choi Sang-June 《Journal of Radioanalytical and Nuclear Chemistry》2019,320(2):329-336
The effect of Tf2N−, as a common anion in aqueous and ionic liquid (IL) phases, on Cs extraction in the IL system was investigated using C2mimTf2N as an IL and DCH18C6 as an extractant. The “common anion (Tf2N−) effect” operated via the movement of Cs+·Tf2N− from the aqueous phase into the IL phase by extraction in the form of Cs+·extractant·Tf2N−, without any traditional cation exchange. The extraction product was recovered as a precipitate using a small amount of IL, which facilitated precipitation via supersaturation.
相似文献10.
O. E. Zhuravlev V. M. Nikol’skii L. I. Voronchikhina 《Russian Journal of General Chemistry》2014,84(6):1141-1145
A low-temperature ionic liquid N-decylpyridinium tetrachloroferrate was synthesized. The temperature dependences of density and viscosity of the synthesized ionic liquid, as well as its thermal stability and magnetic properties were studied. The response of N-decylpyridinium tetrachloroferrate to magnetic field was visualized, and its structure was calculated at the DFT/B3LYB/6-31G(d,p) level of theory. 相似文献
11.
Takashi Iwatsubo Toshio Masuoka Kensaku Mizoguchi 《Journal of Polymer Science.Polymer Physics》1994,32(1):7-13
An equation which represents the swelling equilibrium of an ionic polymer network in a binary liquid mixture is introduced and evaluated numerically. Discontinuous volume changes are obtained with pertinent values of the parameters. From two types of dependence of the degree of ionic dissociation on the composition of a liquid mixture, two types of volume transitions of an ionic gel are illustrated. One is the transition typically seen in acrylamide gels, and the other is a re-entrant transition typical of isopropylacrylamide gels. The selective dissolution factor of two liquids into a swollen polymer network also becomes discontinuous in accordance with the discontinuous volume change. Transition points and the spinodal line are calculated from a generalized form of the free energy change of the swollen gel system. © 1994 John Wiley & Sons, Inc. 相似文献
12.
13.
Reversed-phase liquid chromatographic method for the determination of selected room-temperature ionic liquid cations 总被引:2,自引:0,他引:2
Stepnowski P Müller A Behrend P Ranke J Hoffmann J Jastorff B 《Journal of chromatography. A》2003,993(1-2):173-178
The separation of selected 1-alkyl- and 1-aryl-3-methylimidazolium-based room temperature ionic liquid cations has been performed using reversed-phase high-performance liquid chromatography with electrospray ionization mass detection. The RP-HPLC method development started with the selection of a column taking into account especially the resolution of low molecular congeners of the selected group. Mobile phase composition was optimized for peak resolution, sensitivity and high reproducibility of retention values. The results of the method development were applied to the determination of exemplary ionic liquid species present in the medium used in cytotoxicity studies. 相似文献
14.
15.
The influence of the electrochemical double layer (EDL) structure on the electrochemical processes in ionic liquids is an intriguing subject. The complex layered structure of the EDL and its restructuring have been shown to strongly affect metal deposit morphology and electrochemical reaction kinetics. In this work, we demonstrate that the breakdown of an ionic liquid containing TFSI anions can be catalyzed through the addition of Li+ cations. We ascribe this catalytic effect to the change in the EDL structure: the Li+ cations preferentially adsorb on the electrode surface and drag the TFSI anions with them, facilitating their reduction. The decomposition of the ionic liquid leads to the formation of an SEI layer, which is studied using an electrochemical quartz crystal microbalance. 相似文献
16.
《Solid State Sciences》2012,14(5):598-606
Gel polymer electrolytes containing 1-ethyl-3-methylimidazolium-bis (trifluoromethyl-sulfnyl)imide (EMITFSI) ionic liquid were prepared for lithium ion batteries by solution casting method. Thermal and electrochemical properties have been determined for the gel polymer electrolytes. Proper addition of EMITFSI to the P(VdF-HFP)-LiTFSI polymer electrolyte improves the ionic conductivity and electrochemical window to 2.11 × 10−3 S cm−1 (30 °C) and 4.6 V. In combination of the prepared ternary P(VdF-HFP)-LiTFSI-EMITFSI ionic liquid polymer electrolytes, Li4Ti5O12 anode exhibited two extra voltage plateaus around 1.1 V and 2.3 V except the typical voltage plateau around 1.6 V by possible side reaction between ionic liquid and polymer. LiFePO4 cathode exhibited high capacity above 140 mA h g−1 and retention of 93.1% due to the suppressed polarization effect caused by enhanced ion transport properties. The high temperature of 80 °C didn't have significant impact on the cycling performance. 相似文献
17.
L. V. Zherenkova P. V. Komarov A. N. Belov A. S. Pavlov 《Polymer Science Series A》2012,54(2):147-154
On the basis of the integral equation theory, we examine spatial correlations of flexible polymer chains dissolved in an ionic
liquid. The effect of the concentration of a polymer on its structural properties is studied for different lengths of the
nonpolar tail of the solvent cation. The structure of a polymer-containing ionic liquid is analyzed in the reciprocal space
on the basis of calculated partial structure factors. In a wide range of polymer concentrations, for all the selected values
of length of the cationic nonpolar tail, long-range liquid ordering and intermediate-range liquid ordering of polymer chains
are observed. The dependences of the characteristic scale of ordering of macromolecules on their number density in solution
are different for ionic liquids with different lengths of the cationic nonpolar tail. 相似文献
18.
A. A. Marinin K. G. Khatmullina V. I. Volkov O. V. Yarmolenko 《Russian Journal of Electrochemistry》2011,47(6):717-725
The processes of ionic conductivity are studied in a polymer gel electrolyte synthesized based on polyesterdiacrylate and
a low-molecular solvent ethylene carbonate. The self-diffusion coefficients of solvent molecules and Li+ cations are measured by the NMR with the pulsed magnetic field gradient. The Li+ self-diffusion coefficients increase with the increase in the solvent content and are independent of the diffusion time in
the interval from 10 to 1600 ms. The latter values imply the absence of limitations for the translational mobility of lithium
ions in the spatial range from 10−7 to 10−5 m. Based on the Nernst-Einstein equation, the ionic conductivities are calculated and compared with the experimental conductivities
measured by the impedance method. These values coincide for high contents of solvent; for low ethylene carbonate concentrations,
the calculated conductivities much exceed the experimental values. 相似文献
19.
Rahman MT Fukuyama T Kamata N Sato M Ryu I 《Chemical communications (Cambridge, England)》2006,(21):2236-2238
A low pressure microflow system was developed for palladium-catalyzed multiphase carbonylation reactions in an ionic liquid. The microflow system resulted in superior selectivity and higher yields in carbonylative Sonogashira coupling and amidation reactions of aryl iodides compared to the conventional batch system. 相似文献
20.
The relationships between the ionic mobility, the viscosity, and the atomic-scale structure are investigated in computer simulations of mixtures of LiF and the network glass-forming material BeF(2). The simulations span a wide range of compositions, across which the fluidity of the system changes greatly due to the break-up of the Be-F network by the addition of the LiF. The relationship between the conductivity and viscosity passes from that expected for independently diffusing ions in the dilute mixtures to strongly decoupled Li+ migration through a viscous network at higher concentrations. The transition between these régimes is linked to the changing local and intermediate-scale structure in the melts. The decoupling phenomenon is associated with the appearance of migration channels in the network which leads to cooperative effects in the Li+ migration. 相似文献