藤田 正博

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.

A series of alternating copolymers consisting of chiral thiophene and fluorene, poly[9,9-dihexylfluorene-alt-(3-{2-[(S)-(+)-1-methyloctyloxy]ethyl}thiophene)] (P1), and poly[9,9-dihexylfluorene-alt-(3-{2-[(S)-(+)-1-methyloctyloxy]ethyl}-2,2'-bithiophene)] (P2), were synthesized by Suzuki coupling method. P1 and P2 were characterized by (1)H NMR spectra and elemental analyses. Both of the copolymers showed clear solvatochromism and circular dichroism in methanol/chloroform mixed solutions. These two polymers had different spacer lengths between the chiral side chains along the main chain. and accordingly the circular dichroism spectra were apparently different. (C) 2009 Elsevier B.V. All rights reserved.

Poly[9,9-dihexylfluorene-co-(benzothiazol-2-yl)thiophene-co-9,9'-spirobifluorene] (PF(x)B(y)S(z)) were synthesized by palladium-catalyzed Suzuki coupling reaction. PE(x)B(y)S(z) were characterized by FT-IR,elemental analysis, and (1)H NMR. All the copolymers showed decomposition temperatures above 400 degrees C and glass transition points above 180 degrees C. suggesting that these materials had excellent thermal stability. As the benzothiazolylthiophene content in copolymers was increased, the band gaps of copolymers decreased. All the copolymers exhibited fluorescence peaks in the visible region, and the energy transfer from fluorene to benzothiazolylthiophene units were observed. (C) 2009 Elsevier B.V. All rights reserved.

A series of salts, some of which are ionic liquids, are prepared from cations and anions drawn from Active Pharmaceutical Ingredients (APIs) and Generally Recognized As Safe (GRAS) materials. Using the solid-state structures of the crystalline salts as a basis, an anti-crystal engineering approach to the preparation of "Active Ionic Liquids" (AILs) is explored.

This article reports for the first time the rapid one-pot solvent. free synthesis of 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim]BF(4)), a major ionic liquid, in good yields (87%) after 30 min of microwave irradiation with microwaves at a frequency of 5.8 GHz in a batch-mode reactor. By contrast, the yields of [bmim]BF(4) are about 3-to-4-fold smaller when using 2.45-GHz microwave radiation and oil bath heating: 28% and 21%, respectively, under otherwise identical conditions. This further shows the advantage(s) of the 5.8-GHz microwave radiation and the accompanying apparatus as a novel synthetic tool reported in some detail elsewhere {Org. Process Res. Dev.. 2008, 12, 257-263}. The three synthetic methods (viz., 5.8-GHz and 2.45-GHz microwave heating, and oil bath heating) were examined in reactors used in both the batch and reflux modes. In the latter mode, the yields of [bmim]BF(4) were less than 10% even after a 60-min reaction period. The dependence of the synthesis on the frequency of the microwave radiation is discussed in terms of the chemical yields of the product and the dielectric factors of each substrate in the synthesis mixtures composed of 1-methylimidazole, 1-chlorobutane. and sodium tetrafluoroborate.

Lipase-catalyzed polymerizations of L-lactide were carried out in four kinds of ionic liquids (ILs) in order to investigate the effect of ILs on the conversion, molecular weight, and yield of the obtained poly(lactide) (PLLA). PLLA could be synthesized in ILs of 1-butyl-3-methylimidazolium ([C(4)mim]) except in [C(4)mim][N(CN)(2)]. While the number-average molecular weight (M-n) of the PLLA obtained in [C(4)mim][PF6] was below 4000 g mol(-1) and the yield was below 10%, the M-n and yield of the PLLA obtained in [C(4)mim][BF4] reached 55000g mol(-1) and 35%, respectively. The M-n values of PLLAs in the ILs were clearly higher than those of PLLAs obtained in bulk and in toluene (< 44000 g mol(-1)). The polymerization in the ILs proceeds even at lower temperatures as compared with that in bulk. The effect of lipase content on the M-n of PLLA was also investigated. When [C(4)mim][BF4] was used as the solvent, the highest M,, was obtained at a lipase content of 10wt%,. In the case of [C(4)mim] [NTf2], the most suitable lipase content depended on the polymerization temperature. [C(4)mim][BF4] was suitable to obtain higher molecular weight PLLA and higher polymer yield at lower lipase contents. Copyright (C) 2008 John Wiley & Sons, Ltd.

Poly(L-lactide) (PLLA) has been synthesized by ring-opening bulk polymerization Of L-lactide in porous hydroxyapatite (HAp) matrix without any additional catalyst, and this hybridizing process directly provided artificial bone materials. The obtained PLLA/HAp composites had enough mechanical properties with a bending strength of 53.7MPa, which was 2.3 times stronger than porous HAp, and showed excellent biocompatibility for clinical applications.

Choline dihydrogen phosphate ([N-1.1.1.2OH]DHP) and 1-butyl-3-methylimidazolium dihydrogen phosphate ([C(4)mim]DHP) were synthesized as a new class of proton-conducting ionic plastic crystals. Both [N-1.1.1.2OH]DHP and [C(4)mim]DHP showed solid-solid phase transition(s) and showed a final entropy of fusion lower than 20 J K-1 mol(-1) which is consistent with Timmerman's criterion for molecular plastic crystals. The ionic conductivity of [N-1.1.1.2OH]DHP was in the range of 10(-6) S cm(-1) -10(-3) S cm(-1) in the plastic crystalline phase. On the other hand, the ionic conductivity of [C(4)mim]DHP showed about 10(-5) S cm(-1) in the plastic crystalline phase. [N-1.1.1.2OH]DHP showed one order of magnitude higher ionic conductivity than [C(4)mim]DHP in the temperature range where the plastic phase is stable. (c) 2007 Elsevier B.V. All rights reserved.

We have synthesized two kinds of new Lewis-base ionic liquids (ILs); one is based oil the relatively strong Lewis basic acetate anion, and the other is a salt composed of a mono-alkylated diamine such that the Lewis base site is incorporated in the cation. I-Octyl-4-aza-1-azonia-bicyclo[2.2.2]octane bis(trifluoromethinesulfonyl)amide, [C(8)dabco]TFSA, and N-butyl-N-methylpyrrolidinium acetate, [P-1,P-4]OAc, melted into fluid liquids at 26 and 81 degrees C, respectively. The thermal decomposition of [p(1,4)]OAc started at around 150 degrees C, whereas the thermal stability of [Csdabco]TFSA was almost equal to that of typical TFSA-based ILs in spite of the Lewis base site. This suggests that if the Lewis base site is incorporated into the cation the IL call maintain higher thermal stability. In addition, as a further result of the presence of the basic nitrogen, [C8dabco]TFSA can dissolve hydrated Cu(NO3)(2) whereas the other TFSA-based ILs cannot. (c) 2006 Elsevier Ltd. All rights reserved.

A new Lewis-base ionic liquid (IL) based on mono-charged 1,4-diazabicyclo[2.2.2]octane (dabco) was synthesized and its thermal and electrochemical behaviour was characterized. The dabco-based IL with bis(trifluoromethanesulfonyl)amide (TFSA) anion melts at 76 degrees C when the N-substituted alkyl chain length is 2. The dabco-based IL showed a wide electrochemical window of over 4 V ranging from -3.5 to +1.5 V vs. Fc/Fc(+) and was able to deposit and strip lithium from a nickel substrate at reasonable efficiency. (c) 2006 Elsevier B.V. All rights reserved.

Poly(L-lactide) (PLLA), and poly(ε-caprolactone) (PCL) have received much attention in medical applications because of their biocompatibility and biodegradability. Both PLLA and PCL have insufficient mechanical properties for tissue engineering scaffolds. In this study, poly(L-lactide-co-ε- caprolactone) (PLCL) copolymers were synthesized by ring-opening polymerization of L-lactide (LLA) and ε-caprolactone (ε-CL) in the presence of Pseudomonas lipase (lipase PS) as a catalysis. PLCLs with different LLA-ε-CL ratios were synthesized, and the product was characterized by 1H NMR, gel permeation chromatography (GPC), thermal gravimetry (TG), and differential scanning calorimetry (DSC). The number of molecular weight of PLCL increased with increasing reaction time. The molar fraction of L-lactide in PLCL polymerizing for 9days was equals to the feed ratio of L-lactide. In addition, osteoblast-like MC3T3-E1 cells were cultured on PLLA, PCL, and PLCL cast films.

Hydroxyapatite (Ca10(PO4)6(OH) 2 HAp) has been used as a biomaterial due to its similarity to bone mineral in structure, composition, and its good biocompatibility to human tissue. Recently, much attention has been focused on the combination of HAp with biodegradable polymers to improve the mechanical properties of HAp. In this study, we tried to fabricate poly(lactic-co-glycolic acid) (PLGA)/HAp hybrid materials by the in-situ polymerization in porous HAp ceramics with lipase MML as a catalyst. The effect of feed ratio of L(-)-lactide in PLGA on their biocompatibility was examined. The result of cytotoxicity tests showed that both the adherability and the multiplication of osteoblast-like MC3T3-E1 decreased with adding lactic acid or glycolic acid, because the pH was not suitable for the cell. SEM images showed that osteoblast-like MC3T3-E1 cells were cultured on the composites.

Direct methanol fuel cells (DMFCs) are promising candidates for the application of portable power sources due to the advantage of simple system design and operation. Perfluorosulfonic acid membranes such as Nafion® are widely used as polymer electrolyte membranes in DMFCs because of good chemical and mechanical properties as well as their high proton conductivity. However, there is a few drawbacks including high cost and high methanol permeability. In this study, novel sulfonated poly(4-phenoxybenzoyl-1,4-phenylene) (S-PPBP) - poly(arylene ether ketone-6F) (PAEK-6F) block copolymer (S-PPBP-b-PAEK-6F) was synthesized to decrease the methanol permeability, and the properties of the S-PPBP-b-PAEK-6F membrane were investigated. The S-PPBP-b-PAEK-6F membrane had good thermal stability and showed higher mechanical properties than that of the S-PPBP membrane. The proton conductivity of S-PPBP-b-PAEK-6F membrane achieved 1.04 × 10-1 S/cm at 80°C, 90 %RH, which is comparable to that of Nafion®115 membrane. The methanol permeability of S-PPBP-b-PAEK-6F membrane is 1.09 × 10-6 cm2/s, which is about half than that of S-PPBP and Nafion® membranes.

Biocompatible ceramic, hydroxyapatite (Ca10(PO4) 6(OH)2 HAp), was widely used as substitute material of clinical implants, the mechanical properties of pure HAp, however, was different from that of natural bone. Recently, the composites of biocompatible ceramics and biodegradable polymers were expected as biomaterials for medical applications. In this study, HAp was hybridized with poly(L-lactide) (PLLA) in order to achieve materials with good mechanical properties similar to natural bone. PLLA/HAp composites were fabricated by in-situ polymerization of L-lactide in porous HAp ceramics at 130°C for 7 days. The composites showed excellent bending strength and fracture toughness. In addition, osteoblast-like MC3T3-E1 cells were cultured on the composites in order to investigate their biocompatibility. The rate of multiplication of MC3T3-E1 cells on the PLLA/HAp composites was comparable to that on pure HAp. These results suggested that the introduction of PLLA into porous HAp seem to have positive effects on the application for bone tissue engineering.

Hydrocarbon based polymer electrolyte, sulfonated poly(4-phenoxybenzoyl-1, 4-phenylene) (S-PPBP), is one of the most promising materials for an electrolyte of polymer electrolyte fuel cells. S-PPBP shows high proton conductivity and excellent thermal stability, but the low mechanical properties and poor dimentionaol stability at high water uptakes limit their commercial applications. In this study, m-acetylphenylene (MAP) was introduced to the poly(p-phenylene) backbone to improve the mechanical properties of S-PPBP. Poly(4-phenoxybenzoyl-1,4-phenylene-co-m-acetylphenylene) (P(PBP-co-MAP)) was synthesized by Ni(0) catalyzed coupling reaction. Sulfonation of P(PBP-co-MAP) was performed by stirring of P(PBP-co-MAP) in concentrated sulfric acid. The weight-average molecular weight of sulfonated P(PBP-co-MAP) (S-P(PBP-co-MAP)) was 55,000, and the ion exchange capacity of S-P(PBP-co-MAP) was 2.84 meq g -1. Proton conductivity of the S-P(PBP-co-MAP) membrane was 1.1 × 10-1 S cm-1 at 80°C under 90%RH, which is comparable to that of Nafion®15 membrane. Water uptake of the S-P(PBP-co-MAP) membrane was 64% at r.t. under 100%RH that is lower than that of the S-PPBP membrane.

Polythiophene derivatives show interesting optical and electrical properties. Especially, optically active polythiophene derivatives have attracted much attention because of their unique structures and organization properties. These properties are greatly dependent on the degree of regioregularity, which can be defined as the percentage of Head-to-Tail couplings. In this study, optically active regioregular polythiophene, HT-PMOETs (HT-P(S)MOET and HT-P(R)MOET) were synthesized and applied to EL devices. Both HT-PMOETs had about 95 % Head-to-Tail couplings and showed large Cotton effects in a poor solvent. Multi-layer EL devices with the configuration of ITO/PEDOT:PSS/HT-PMOET/Alq3/Al-Li emitted at 750 nm, indicating that HT-PMOETs worked as an emission layer.

Polycarbonate (PC) is one of super engineering plastics with good transparency and impact-resistance. However, the surface hardness of PC is insufficient for optical and practical applications. Poly(benzoyl-1,4-phenylene) (PBP) has good mechanical properties and transparency. In this study, we synthesized a novel copolymer, poly(benzoyl-1,4-phenylene-co-4-fluorobenzoyl-1, 4-phenylene) (PBP-co-PFBP) using Ni(0) catalysts. The blend films comprised of PC and PBP-co-PFBP with various contents were fabricated by a solvent casting method. All PC/PBP-co-PFBP blend films showed good optical transmittance no less than 85 % at 700 nm. Surface hardness of the PC/PBP-co-PFBP blend films was estimated by optical transmittance at 700 nm before and after abrasion by using a coating tester with steel wool. The results of hardness tests showed that surface hardness of the PC/PBP-co-PFBP blend films increased with increasing PBP-co-PFBP ratio.

Electrode electrolyte (binder) materials in polymer electrolyte fuel cells (PEFCs) are usually fluorocarbon polymers. By using the hydrocarbon polymers as the binder, the environmental problems may be solved, and the development of high-temperature PEFCs with low cost may be possible. In this study, sulfonated poly(4-phenoxybenzoyl-l,4-phenylene) (S-PPBP) was synthesized, and S-PPBP was used for the binder. The ion exchange capacities of S-PPBPs were estimated as 2.83 (Mw=85,000) and 2.78 (Mw=168,000) meq/g by titration. The performance of the MEA with the S-PPBP (Mw= 168,000) binder and a Nafion®115 electrolyte membrane was higher than that with the S-PPBP (Mw=85,000) binder. The maximum power density (122 mW/cm2) was observed when the both amounts of Pt and S-PPBP (Mw= 168,000) were 1.0 mg/cm2 (S-PPBP/Pt=1.0). As a result of the PEFC performance and SEM images, the most suitable composition of the electrode was found to be Pt/S-PPBP=1.0.

Polymer electrolyte fuel cell (PEFC) is one of the most promising candidate systems for novel electric generation. Recently, hydrocarbon polymer electrolytes have received much attention due to lower cost, compared with perfluorinated polymer electrolytes such as Nafion®. Polyhedral oligomeric silsesquioxane (POSS) contains an inorganic Si8O12 core surrounded by organic substitutes. It has been reported that aggregation of POSS in various polymer materials improved the mechanical and thermal properties of the polymers. In this study, POSS was introduced into polymer electrolyte materials in order to control the water absorption properties. Phosmer (PHM)-co-POSS and sulfoneted polystyrene-co-POSS were synthesized, and various properties such as X-ray diffraction, proton conductivity, and dimensional change were investigated. The XRD pattrens indicated that POSS in both the copolymers crystallized in hexagonal crystalline as well as POSS macromonomers. P(PHM-co-POSS) and S-P(St-co-POSS) showed the maximum proton conductivity of 3.2 × 10-2 and 4.7 × 10-2 S/cm at 80°C and 90 %R. H., respectively. Dimensional changes were investigated by immersing the sample membranes into water at 80°C. The swelling ratio of S-P(St-co-POSS) membrane was lower than that of sulfonated polystyrene (SPS) membrane.

Sulfonated poly(4-phenoxybenzoyl-1,4-phenylene) (S-PPBP) is an excellent polymer electrolyte having a high proton conductivity. However, S-PPBP has a poor dimentional stability and difficulty in fabricating flexible films due to the rigid main chains. On the other hand, poly(ether sulfone) (PES), which has a flexible structure, shows a good dimension stability. In this study, two kinds of Cl terminated PES oligomers (Cl-PES24, Cl-PES12) were synthesized. The number of repeating unit of Cl-PES24 and Cl-PES12 was calculated by 1H NMR to be 38 and 17, respectively. A novel PPBP-PES block copolymer (PPBP-b-PES) was synthesized via Ni(0) coupling reaction of 2,5-dichloro-4'-phenoxybenzophenone and Cl-PES12. The obtained block copolymers were characterized by FT-IR, 1H, 13C NMR, and elemental analysis. PPBP-b-PES had Mn=38,100, Mw=106,800, and PDI=2.80, as determined by GPC analysis calibrated with polystyrene standards. The same copolymerization with Cl-PES24 could hardly proceed.

Superhydrophobic surfaces with a water contact angle over 150° are expected to be applied on medical and environmental fields. In this study, we fabricated superhydrophobic thin films using poly(tetrafluoroethylene) (PTFE) particles and various F-containing copolymers by a conventional self-assembly method. Contact angles of water on both self-assembled (SA) films increased relative to number of bilayers. However, these SA films didn't show superhydrophobicity as a PTFE/PPHP films.

Hydroxyapatite (Ca10(PO4)6(OH) 2 HAp) has biocompatibility, but its mechanical strength is not enough to apply to organism tissue substitution materials. In this study, HAp was hybridized with PLLA in order to achieve biocompatible materials with high toughness. HAp/PLLA composites were fabricated by polymerizing L-lactide with lipase CA at 130°C for 7 days in porous HAp ceramics. Moreover, it was tried to increase the number of hydroxyl groups on the surface of HAp by the hydrothermal treatment, and the relationship between PLLA contents of composites and their mechanical properties were investigated. As the pH of the hydrothermal treatment increased, the porosity of composites decreased, whereas the mechanical properties of bending strength and fracture toughness increased.

Poly(L-lactide) (PLLA), which is an important material for medical applications, are usually synthesized by metal catalysts. Enzymatic polymerization with lipase receives much attention as an example of a new methodology of polymer syntheses in the context of green chemistry. There are some ambiguous parts in enzymatic polymerization mechanism. In this study, PLLA was synthesized by lipase-catalyzed polymerization with various water contents, or without lipase. The effect of lipase and water content on the conversion, the molecular weight, and the crystallinity of the obtained PLLA were investigated. In the case of lipase-catalyzed polymerization, the conversion of L-lactide were constant independent of the water volume, and the molecular weight of PLLA decreased with the water volume. On the contrary, the conversion of L-lactide decreased with the water volume, and the Mw of PLLA synthesized without lipase were constant independent of the water volume.

Alternating copolymer of chiral thiophene and non-substituted thiophene, poly(3-[2-((S)-(+)-1-methyloctyloxy)ethyl]-2,2'-bithiophene) (P(S)MOET-T), and the regioregular chiral polythiophene, head-to-tail poly(3-[2-((S)-(+)-1- methyloctyloxy)ethyl]thiophene) (HT-P(S)MOET), were synthesized by Rieke method. The molecular weight of P(S)MOET-T and HT-P(S)MOET were MW = 28,000 and 38,000, respectively. The head-to-tail ratios of P(S)MOET-T and HT-P(S)MOET were estimated to be 95 % by 1H NMR. Bandgaps of P(S)MOET-T and HT-P(S)MOET, which were calculated from UV-Vis absorption spectra, were 1.94 eV and 1.83 eV, respectively. Cyclic voltammetry of P(S)MOET-T and HT-P(S)MOET cast films were measured in a 0.1 M Bu4NBF4/acetonitrile solution. Oxidation onset potential of P(S)MOET-T, HT-P(S)MOET were 0.45 V and 0.70 V, respectively.

Hydrocarbon polymer electrolytes based on poly(phenylene), sulfonated poly(4-phenoxybenzoyl-1,4-phenylene) (S-PPBP), shows high proton conductivities and excellent fuel cell performances. However, their mechanical properties at high water uptakes and chemical stability were insufficient. In this study, we tried to synthesize high molecular weight PPBP in order to improve chemical stability and mechanical properties. Various synthesis conditions including catalysts, ligands, solvents, and reaction temperatures were investigated. High molecular weight polymers were only obtained by using NiCl2(PPh 3)2 as a catalyst and PPh3 as a ligand. NMP was the most effective solvent for PPBP synthesis. Under these reaction conditions, reaction temperature was an important factor. At 65°C, the highest molecular weight were obtained.