Fujita Masahiro

Lemon myrtle is the richest natural source of citral, which has potential medicinal applications. In this study, citral was extracted from lemon myrtle using cellulose-dissolving ionic liquids (ILs), 1-ethyl-3-methylimidazolium methylphosphonate ([C(2)mim][(MeO)(H)PO2]), N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium chloride ([DEME]Cl), and N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium 2-methoxyacetate ([DEME][MOAc]). The extraction yield of citral obtained using ILs was up to 2.1 times higher than that obtained using ethanol. The ILs could be recycled and reused nine times for the extraction of citral. The present method provides a greener process when compared with conventional approaches and may be applicable for the extraction of other natural products.

Two-dimensional perovskite compounds, ((RNH32PbX4)-Pb-), have attracted much attention as quantum confinement materials. To achieve suitable orientation and exciton properties for optical applications, carboxy groups were introduced into the ammonium cations of two-dimensional perovskite compounds, which formed dimer structures based on the hydrogen bonding by the carboxy moieties. This structural organization allowed control of the layer orientation for favorable solar cells and thermal stability of the perovskites, while maintaining quantum confinement effects.

Geranial [(E)-3,7-dimethyl-2,6-octadienal], neral [(Z)-3,7-dimethyl-2,6-octadienal] and geraniol [(E)-3,7-dimethyl-2,6-octadien-1-ol] are found in lemon grass and are attractive essential oils with potential medicinal applications. In this study, a new method for extracting these natural flavour substances from lemon grass using co-solvent systems consisting of methanol or ethyl acetate and the ionic liquids 1-butyl-3-methylimidazolium chloride ([C4mim]Cl) or 1-ethyl-3-methylimidazolium methylphosphonate ([C2mim][(MeO)(H)PO2]) is described.

Aromatic ionomers with perfluoroalkyl sulfonic acid groups for fuel cell applications have been prepared mostly by the post-functionalization method. Herein, we present a direct polymerization method using a novel monomer with a perfluorosulfonic acid group to control the amount and position of the sulfonic acid groups. A poly(p-phenylene)-based aromatic hydrocarbon ionomer bearing a pendant perfluorosulfonic acid group in a substituent at the 2-position is synthesized by Ni(0)-catalyzed coupling polymerization. The direct polymerization provides Mn values of up to 169 000 with a highly controlled molecular structure and allows the formation of thin membranes. These ionomers were found to combine the positive features of perfluorinated and aromatic hydrocarbon ionomers, and these thin membranes with a relatively high ion exchange capacity showed high proton conductivity and excellent fuel cell performance (907 mW cm-2 even at 80 °C and 30% RH) under low humidity conditions compared with other reported aromatic hydrocarbon ionomers.

Ionic liquids (ILs) containing zwitterions have been studied as electrolytes for lithium-ion batteries (LIBs). The effects of addition of a pyrrolidinium zwitterion in an IL electrolyte on the thermal and electrochemical stability and charge/discharge properties of Li/LiCoO2 and graphite/Li cells were investigated. The thermal decomposition temperature of the IL electrolyte composed of N-methyl-N-propylpyrrolidinium bis(fluorosulfonyl)amide ([P13][FSA])/lithium bis(trifluoromethylsulfonyl)amide (LiTFSA) with 3-(1-butylpyrrolidinium)propane-1-sulfonate (Bpyps) as the zwitterionic additive, the thermal decomposition temperature was about 300 degrees C. The electrochemical window of [P13][FSA]/LiTFSA/Bpyps was 0 -+5.4 V vs. Li/Li+, which was almost identical to that of [P13][FSA]/LiTFSA. Li vertical bar electrolyte vertical bar LiCoO2 cells containing the IL/Bpyps electrolyte system exhibited high capacities in the cut-off voltage range of 3.0 -4.6 V, even after 50 cycles. The increase in the interfacial resistance between the electrolyte and cathode with cycling was suppressed. In the cyclic voltammograms of cells employing a graphite electrode, the intercalation/deintercalation of lithium ions were observed in the range of 0 and + 0.4 V vs. Li/Li+. Further, graphite vertical bar electrolyte vertical bar Li cells containing [P13][FSA]/LiTFSA/Bpyps exhibited stable charge/discharge cycle behaviour over 50 cycles. (C) 2016 Elsevier B.V. All rights reserved.

The ionic liquid (IL) N-Methyl-N-methoxymethylpyrrolidinium bis(fluorosulfonyl)amide ([Pyr(1,101)][FSA]) was synthesized, and its physicochemical and electrochemical properties were investigated with respect to its application as an electrolyte in lithium-ion secondary batteries operating over a wide temperature range. [Pyr(1,101)][FSA]/Li salt (0.34 mol kg) composites were prepared by adding lithium bis(tri-fluoromethylsulfonyl)amide (LiTFSA) into the IL. [Pyr(1,101)][FSA] and [Pyr(1,101)][FSA]/LiTFSA exhibited melting temperatures (T-m) below 30 degrees C. [Pyr(1,101)][FSA] exhibited a higher ionic conductivity value as compared with that of the corresponding IL with only alkyl substituents. The electrochemical window for both [Pyr(1,101)][FSA] and [Pyr(1,101)][FSA]/LiTFSA was 5.1 V. Stable lithium deposition and dissolution occurred on a Ni electrode at 25 degrees C. (C) 2016 Elsevier B.V. All rights reserved.

Zwitterions with a cyano group on the side chain (CZ) were synthesized. Although the addition of CZ caused a slightly negative effect on viscosity, ionic conductivity, limiting current density, and lithium transference number, the oxidation limit of PEGDME/lithium bis(trifluoromethylsulfonyl) amide (LiTFSA) composites was improved to over 5 V. For charge/discharge testing using Li vertical bar electrolyte vertical bar LiCoO2 cells, the cycle stability of PEGDME/LiTFSA with CZ in the voltage range of 3.0-4.6 V was much higher than that of PEGDME/LiTFSA. Incorporating a small mole fraction of CZ into PEGDME-based electrolytes prevented an increase in the interface resistance between the electrolyte and cathode with increasing numbers of the cycle. (C) 2015 Elsevier Ltd. All rights reserved.

A protocol for extracting the terpene trilactone bilobalide from Ginkgo biloba leaves using the cellulose-dissolving ionic liquid 1-butyl-3-methylimidazolium chloride ([C(4)mim]Cl) was developed. Extraction with [C(4)mim]Cl/MeOH (1:1 w/w) at 80 degrees C afforded bilobalide with a yield of 0.14% w/w, which was 1.4 times higher than that achieved using conventional MeOH at 80 degrees C (0.098% w/w).

Solid polymer electrolytes show great potential in electrochemical devices. Poly(ethylene oxide) (PEO) has been studied as a matrix for solid polymer electrolytes because it has relatively high ionic conductivity. In order to investigate the effect of zwitterions on the electrochemical properties of poly (ethylene glycol) dimethyl ether (G5)/lithium bis(fluorosulfonyl) amide (LiFSA) electrolytes, a liquid zwitterion (ImZ2) was added to the G5-based electrolytes. In this study, G5, which is a small oligomer, was used as a model compound for PEO matrices. The thermal properties, ionic conductivity, and electrochemical stability of the electrolytes with ImZ2 were evaluated. The thermal stabilities of all the G5-based electrolytes with ImZ2 were above 150 degrees C, and the ionic conductivity values were in the range of 0.8-3.0 mS cm(-1) at room temperature. When the electrolytes contained less than 5.5 wt% ImZ2, the ionic conductivity values were almost the same as that of the electrolyte without ImZ2. The electrochemical properties were improved with the incorporation of ImZ2. The anodic limit of the electrolyte with 5.5 wt% ImZ2 was 5.3 V vs. Li/Li+, which was over 1 V higher than that of G5/LiFSA. (C) 2014 Elsevier Ltd. All rights reserved.

Poly(L-lactic acid-co-glycolic acid)/hydroxyapatite (PLGA/HAp) composites were fabricated by the in situ polymerization of L-lactide and glycolide in porous HAp disks, using lipase MM, derived from Mucor miehei, as a catalyst. Various PLGA/HAp composites were obtained by changing the feed ratio of L-lactide and glycolide. The fourier transform infrared spectroscopy, scanning electron microscopy and porosity measurements showed that the porous HAp was completely filled with PLGA after polymerization at 100 degrees C for 9 days. Lactyl unit fractions (FL) of obtained PLGA calculated from the 1H nuclear magnetic resonance were consistent with the feed fraction of L-lactide (fL). The PGA/HAp, PLGA20/HAp, PLGA50/HAp, PLGA80/HAp and PLLA/HAp composites showed maximum bending strengths of 91.1 MPa, 78.8 MPa, 73.4 MPa, 54.3 MPa and 67.0 MPa, respectively. These values were 4.7-2.8 times greater than that of the untreated porous HAp disks and were suitable for artificial bone materials. The cell adhesion and proliferation properties of these materials with osteoblast-like MC3T3-E1 cells suggest that these PLGA/HAp composites have suitably bioactive surfaces. The PLGA/HAp composites showed higher alkaline phosphatase activity after cultivation of rat bone marrow stromal cells.

In order to investigate the effects of lithium salt species and concentration on the electrochemical properties of a liquid zwitterion (LZw), composites of a LZw with lithium bis(fluorosulfonyl) amide (LiFSA) or lithium bis(trifluoromethylsulfonyl) amide (LiN(Tf)(2)) were prepared at various lithium salt concentrations. The majority of LZw/LiFSA and LZw/LiN(Tf)(2) composites with lithium salt mole fractions in the range of 0.2 to 0.8 were obtained as colorless liquids and exhibited glass transitions only during DSC measurements. The dissociation state of the lithium salts in the composites was discussed by means of FT-IR measurements. The interactions between the imidazolium cation and the amide anions were demonstrated. The LZw/LiFSA composite with a LiFSA mole fraction of 0.8 (corresponding to a concentration of 13.7 mol kg(-1)) exhibited the highest ionic conductivity (1.2 x 10(-5) S cm(-1)) as well as the greatest lithium transference number (0.46) at 40 degrees C.

We synthesized new polymer electrolytes containing zwitterions [P(MEO-co-Zw)] by reacting an imidazole derivative with the p-chloromethylstyrene groups in a random methacryloyl oligo(ethylene oxide) (MEO/p-chloromethylstyrene (CMS) copolymer [P(MEO-co-CMS)]. The weight-average molecular weight of P(MEO-co-CMS) was about 200,000 g mol(-1), and P(MEO-co-Zw) formed flexible films. P(MEO-co-Zw)/LiTFSA composites exhibited two glass transition temperatures at around -70 degrees C and -10 degrees C. Contrary to usual polyether electrolytes, the ionic conductivity and lithium ion transference number of P(MEO-co-Zw)/LiTFSA composites remained constant even at high lithium salt concentration, because the high dipole moment of the zwitterions leads to a strong solvation of lithium salt through the electrostatic interaction.

Diblock copolymer ionomers SP1-P2(m-n) with ion exchange capacity (IEC) of 0.96-2.42 meq g(-1) were prepared. The parent diblock copolymers P1-P2(m-n) having various block lengths (m, n) were synthesized via successive catalyst-transfer polymerization of 1,4-dibromo-2,5-di[4-(2,2-dimethylpropoxysulfonyl)phenyl]butoxybenzene (1) and 1,4-dibromo-2,5-hexyloxybenzene (2). The molecular weights were successfully controlled by the feed ratio of the monomer and catalyst, and the molecular weight distribution values were less than 1.32, irrespective of the polymerization degree or polymerization order. Preliminary morphological studies showed that the diblock copolymer ionomers SP1-P2(m-n) had a clear phase separation that could be controlled by the ratios and lengths of the hydrophilic and hydrophobic units. The ionomers showed high proton conductivities with a small humidity dependence, indicating that the clear phase separation formed by the precisely controlled molecular weight and polydispersity index (PDI) of the diblock copolymers enhanced the ionic connectivity and proton conductivity.

A novel organic ionic plastic crystal, N-ethyl-N-methyl-pyrrolidinium bis(fluorosulfonyl)amide ([C2mpyr][FSA]), was synthesized, and its thermal properties and conductivity were investigated. [C2mpyr][FSA] showed a high melting point at 205°C and exhibited plastic crystalline behavior over a wide temperature range from -22°C to melting, which was also in a desirable temperature range for electrochemical devices. The ionic conductivity of [C2mpyr][FSA] was 1.23 × 10-6 S cm-1 at 25°C.

We synthesized sulfonated poly[(4-phenoxybenzoyl)-1,4-phenylene-co-anthraquinone] copolymers (S-P(PBP-co-ANQ)s) in order to investigate the effect of polycyclic units on the water uptake, dimensional stability, and proton conductivity. The effect of the binding positions of anthraquinone (ANQ) was also investigated by preparing S-P(PBP-co-1,4ANQ) and S-P(PBP-co-1,5ANQ), each with 5 mol% ANQ. Number-average molecular weights and thermal decomposition temperatures of S-P(PBP-co-ANQ)s were about 50-70 kgmol(-1) and 220 degrees C, which were sufficient for polymer electrolyte fuel cell (PEFC) applications. S-P(PBP-co-1,5ANQ) membranes showed higher dimensional stability and proton conductivity than S-P(PBP-co-1,4ANQ) and S-PPBP membranes. The maximum current densities and power densities of S-P(PBP-co-1,5ANQ) fuel cells were 2200mA cm(-1) and 800 mW cm(-2) at 80 degrees C and 100% relative humidity. These results suggest that the improvement of dimensional stability and electrochemical properties is due to strong aggregation of the copolymer chains induced by ANQ at an appropriate coupling position.

Biphasic calcium phosphate (BCP) ceramics with wellcontrolled pores were fabricated by sintering mixtures of synthetic hydroxyapatite (HAp) and deoxyribonucleic acid (DNA). BCP ceramics with macro- and micropores revealed excellent cell proliferation as a result of suitable surface topography and phase composition. © 2013 The Chemical Society of Japan.

Poly(p-phenylene) derivatives with pendant-type side chains of various lengths were synthesized in order to investigate the effect of side chain structure on properties such as sulfonation, thermal stability, mechanical strength, water uptake, dimensional stability, proton conductivity, and polymer electrolyte fuel cell (PEFC) properties. The sulfonation reactions were affected by the electron density of side chains. All sulfonated polymers showed thermal stabilities up to 240 degrees C, which is sufficient for polymer electrolyte membranes used in PEFC. Although the glass transition temperatures were about 200 degrees C regardless of the side chain structure, the mechanical strength was influenced by the side chain length. The number of adsorbed water molecules per sulfonic acid group (X) decreased with increasing side chain length, resulting in a lower swelling ratio. The proton conductivity increased with an increase in ion exchange capacity and lambda, and S-P1(2.79), Which has the shortest side chain, showed the highest proton conductivity. All the sulfonated polymer membranes exhibited sufficient cell performance, but S-P2(2.27) showed the highest performance, revealing a different order of performance among the membranes from that of proton conductivity. It is suggested that the higher water uptake of S-P1 provides not only higher proton conductivity but also lower carrier density, resulting in increased membrane resistance in fuel cell tests.

A new ionic liquid was prepared by introducing a boronic acid group to an imidazolium cation with a hydrophobic anion. The boronic acid-containing ionic liquid showed the best ionic conductivity of 6.5 × 10-4 S cm-1 at 50 °C, with a high lithium ion transference number of over 0.5, owing to the anion-trapping effect of the boronic acid group. © 2013 The Chemical Society of Japan.

Poly(L-lactic acid) was synthesized in ionic liquids by lipase-catalyzed ring-opening polymerizations. A lower molecular weight poly(L-lactic acid) (PLLA) and a higher molecular weight PLLA were obtained in the same batch. When up to 5 wt. % water was added, the ratio of the higher molecular weight PLLA increased with increasing water content. Also, the specific rotation of PLLAs increased, indicating that PLLAs with a high optical purity were obtained by the lipase-catalyzed polymerization of L-lactide in hydrated ILs.

Shikimic acid was first isolated in 1885 by Eijkman from the fruit of the Japanese plant Illicium religiosum. Many natural plants contain shikimic acid for biosynthesis as an important intermediate. Roche pharmaceutical uses shikimic acid from star anise as a starting material for production of Tamiflu. However, isolation of star anise from natural resources has been limited. Here we report efficient and new isolation protocol of shikimic acid from Ginkgo biloba leaves utilizing an ionic liquid that dissolves cellulose. Shikimic acid was efficiently extracted and isolated from G. biloba leaves utilizing an ionic liquid 1-butyl-3-methylimidazolium chloride ([bmim]Cl), which is able to dissolve cellulose. Using the ionic liquid at 150 ℃ gave an extraction yield of 2.3% w/w for shikimic acid, which was 2.5 times higher than that for methanol at 80 ℃ (0.93% w/w). Meanwhile, an isolation protocol for obtaining shikimic acid in good yield from the IL phase using an anion-exchange resin Amberlite IRA-400 Cl form was established. The SEM micrograph of the leaves after extraction showed a significantly different morphology, with the larger features completely broken down into much smaller structures, indicating that the G. biloba leaves were much more highly dissolved in [bmim]Cl compared to in methanol The present procedure could lead to a convenient supply of shikimic acid, thus enabling production of greater amounts of the antiviral agent Tamiflu. The protocols are also likely to be applicable to other plant leaves, allowing for isolation of greater quantities of other natural products as well as unknown natural compounds.

Hydrophilichydrophobic block copolymer ionomers based on polyphenylenes with controlled the block lengths were synthesized for the first time by a catalyst-transfer polycondensation of a dibromo phenylene derivative having a neopentyl ester protected sulfonic acid group, followed by the polycondensation of hydrophobic dibromo hexyloxybenzene. The diblock copolymer ionomers were obtained by the removal of neopentyl groups, resulting in clear phase separation dependent on the block lengths. The well-developed microphase separation provided controlled water uptake and sufficiently high proton conductivity, especially at low relative humidity conditions. The fine block copolymerization by using catalyst transfer polycondensation is a promising strategy for the development of hydrocarbon ionomers having well-defined ordered structures with reasonable proton conductivity for fuel cell applications.

Oligothiophene derivatives, 4,4′-bis-(2-aminoethylthienyl)-3,4- ethylenedioxythiophene dihydrohalide (AET-EDOT·HX: X = I, Br), were synthesized by Grignard coupling reactions. The hybrid films of oligothiophene and lead halide were fabricated by casting and spin-coating methods. The effect of halogen species on the optical properties of the perovskites was investigated. The X-ray diffraction profiles of (AET-EDOT)PbX 4 cast films indicated that the layered structures were formed by the self-organization. After hybridization of AET-EDOT·HX with PbX 2, new absorption peaks due to the confined excitons were observed at 400 nm for (AET-EDOT)PbBr 4 film, and at 395 nm for (AET-EDOT)PbI 4 film. These results indicated that the diamino-type oligothiophenes were successfully incorporated into the organic-inorganic layered perovskites. AFM images of (AET-EDOT)PbX 4 cast films showed polycrystalline grains, indicating that the polycrystalline structures covered on the substrate surface. © (2012) Trans Tech Publications, Switzerland.

A chiral polyfluorenethiophene derivative incorporating two different chiral side chains was synthesized via the Suzuki coupling reaction. Upon photoexcitation, thin films of the polymer exhibited efficient circularly polarized luminescence in the visible range, even without thermal annealing. The dissymmetry factor, g lum, of films with thicknesses less than 100nm reached 0.2 at 505 nm. © 2012 The Chemical Society of Japan.

Lithium was electrochemically inserted from a Li(+) ion containing ionic liquid into graphite or tin to observe lithium isotope effects that accompanied the insertion. While no preferential uptake of the lithium isotopes was detected with graphite, the lighter isotope, (6)Li, was preferentially fractionated into tin with the single-stage lithium isotope separation factors, S, ranging from 1.004 to 1.008 at 25 degrees C. It was speculated that a Li(+) ion was inserted into graphite together with an anionic component of the ionic liquid and, upon the reduction of the Li(+) ion to a lithium atom, the anion was released from graphite, while a Li(+) ion alone was inserted into tin. Molecular orbital calculations supported this speculation in a qualitative fashion. (C) 2011 Elsevier Ltd. All rights reserved.

An imidazolium-based zwitterion containing two oxyethylene units was obtained as a colorless liquid at room temperature. The equimolar mixture of the liquid zwitterion and lithium bis(trifluoromethylsulfonyl) amide showed an ionic conductivity of over 10(-4) S cm(-1) at 80 degrees C, which was higher than those of mixtures composed of analogous solid zwitterions.

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 degrees C, and its thermal stability was higher than 400 degrees 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 x 10(-3) S cm(-1) at 25 degrees 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 H-1 NMR, the self-diffusion coefficient of the H-1 of the hydroxyl group and the acid was larger than those of other H-1 nuclei. This difference suggests that a fast intermolecular proton transfer exists between the hydroxyl group and the acid.

Shikimic acid, the starting material in the commercial synthesis of oseltamivir phosphate (Tamiflu (R)), was efficiently extracted and isolated from Ginkgo biloba leaves utilizing the ionic liquid 1-butyl-3-methylimidazolium chloride ([bmim]Cl), which dissolves cellulose.

We describe zwitterion, 3-(1-buty1-1H-imidazol-3-ium-3-y1)propane-1-sulfonate (Bimps), mixtures with 1,1,1trifluoro-N-(trifluoromethylsulfonyl)methanesulfoneamide (HN(Tf)(2)) as new proton transport electrolytes. We report proton transport mechanisms in the mixtures based on results from several methods including thermal analyses, the complex-impedance method, and the pulsed field gradient spin echo NMR (pfg-NMR) method. The glass transition temperature (Tg) of the mixtures decreased with increasing HN(Tf)(2) concentration up to 50 mol %. The Tg remained constant at - 55 degrees C with further acid doping. The ionic conductivity of HN(11)2 mixtures increased with the HN(Tf)(2) content up to 50 mol To. Beyond that ratio, the mixtures showed no increase in ionic conductivity (10(-4) S cm(-1) at room temperature). This tendency agrees well with that of Tg. However, the self-diffusion coefficients obtained from the pfg-NMR method increased with HN(Tf)(2) content even above 50 mol % for all component ions. At HN(Tf)(2) 50 mol %, the proton diffusion of HN(Tf)(2) was the fastest in the mixture. These results suggest that Bimps cannot dissociate excess HN(Tf)(2), that is, the excess HN(Tf)(2) exists as molecular HN(Tf)(2) in the mixtures. The zwitterion, Bimps, forms a 1:1 complex with HN(Tf)(2) and the proton transport property in this mixture is superior to those of other mixing ratios. Furthermore, CH3SO3H and CF3SO3H were mixed with Bimps for comparison. Both systems showed a similar tendency, which differed from that of the HN(Tf)(2) system. The Tg decreased linearly with increasing acid content for every mixing ratio, while the ionic conductivity increased linearly. Proton transport properties in zwitterion/acid mixtures were strongly affected by the acid species added.

Multilayer-type polymer electrolyte membranes composed of a sulfonated poly(4-phenoxybenzoyl-1,4-phenylene) (S-PPBP) layer and a mono[ poly(propylene oxide)methacrylate] phosphate ester (PPHP) layer were fabricated by solution-casting procedure (Method 1) and hot-pressing procedure (Method 2) in order to suppress methanol permeability of electrolyte membranes. No delamination was observed by SEM measurements of S-PPBP/PPHP interfaces, indicating that PPHP had good adhesive properties to S-PPBP surfaces. The methanol permeability of S-PPBP/PPHP membranes was lower than that of S-PPBP membranes and decreased with increasing the thickness of PPHP layers. The bilayer membrane with 12 mu m PPHP and 40 mu m S-PPBP layers showed a methanol permeability of 2.97 x 10(-7) cm(2) s(-1) in 1 mol dm(-3) methanol aqueous solution at 25 degrees C, which was 13% less than that ofthe S-PPBP membranes. The conductivity of this membrane reached its optimum with values as high as 1.57 x 10(-1) S cm(-1) at 80 degrees C and 90%RH. (C) 2009 Elsevier Ltd. All rights reserved.