小林 範久

Lyotropic liquid crystalline cell composed of polypeptide having carbazolyl groups (poly(γ-[2-(9-carbazolyl)ethyl]-L-glutamate) (PCLG) was studied to analyze the novel electro-optical effect, in which the transparent cell became scattering under applying d.c. bias voltage. The absorption at 350-600nm was increased under d.c. bias application, leading to the scattering behavior. Effect of hole transport properties of PCLG on the scattering behavior was discussed. Direct observation was also examined to clarify this scattering behavior.

Lyotropic liquid crystalline cell composed of polypeptide having carbazolyl groups (poly(γ-[2-(9-carbazolyl)ethyl]-L-glutamate) (PCLG) was studied to analyze the novel electro-optical effect, in which the transparent cell became scattering under applying d.c. bias voltage. The absorption at 350-600nm was increased under d.c. bias application, leading to the scattering behavior. Effect of hole transport properties of PCLG on the scattering behavior was discussed. Direct observation was also examined to clarify this scattering behavior.

We have already prepared PAn/DNA complex via photopolymerzation and have demonstrated EL device with PAn/DNA complex. However, emission and charge transport mechanism in this device are still not clear. It is necessary to clarify charge transport mechanism of PAn/DNA complex in order to prepare high-efficiency EL device. In this research, we measured charge carrier mobility of some complexes by means of Time of Flight technique and studied charge transport properties.

Fossil fuels must be more efficient and their environmental impact from power plants be reduced. Mitsubishi Heavy Industries, Ltd., has applied proprietary deNOx effluent technology to a variety of boiler. To improve higher deNOx efficiency, advanced measurement is necessary to control deNOx effectively. This study introduces a simultaneous NOx/NH3sensor based on an NGK Insulators, Ltd., NOx sensor. The NOx/NH3sensor provides simultaneous, continuous measurement and high response.

A selective catalytic reduction (SCR) of nitrogen oxide catalysts for low sulphur dioxide oxidation activity was developed. Surface treated improved de-NOxcatalysts were installed in high sulfur heavy oil fired thermal power plants. Numerous flue gas dentrification techniques were researched and developed of systems based on the SCR method using NH3as reducing agent. The technologies were widely used in various flue gas treating facilities including refuse incinerators, electric furnaces and sintering ovens.

Photopolymerization of an aniline dimer, i.e., N-phenyl-p-phenplenediamine (PPD), by photoinduced electron transfer between tris(2,2 ' -bipyridyl)ruthenium complex (Ru(bpy)(3)(2+)) and PPD was studied in aerated acidic aqueous solution in the presence of an anionic micelle, i.e., sodium dodecyl sulfate (SDS), leading to polyaniline (PAn) / micelle complex formation. The structure of the complex and its mechanism were considerably affected by concentration of SDS.

The photopolymerization of aniline derivatives was investigated in solid state with Flemion film containing Ru(bpy)(3)(2+) and PPD (N-phenyl-p-phenylenediamine) in order to form well-defined photo-image. Absorption spectrum indicated that the photopolymerization was succeeded even in a solid state. TG-DTA analysis showed that trace amounts of water (less than or equal to 1wt.%) remained in the film, suggesting that the trace amounts of water is of important for the photopolymerization in solid state. Consequently, well-defined sub-micropattern was successfully formed by the photopolymerization of aniline derivatives in solid state.

The axial velocity, radial velocity and concentration of a high Schmidt number matter were measured simultaneously in an axisymmetric turbulent jet. The diffusing fluid is a water solution of the commercial dye (Schmidt number Sc≃3 800), and an issuing Reynolds number is 6 400. A combined probe of a fiber optic concentration sensor and a X-type hot film was used to measure the axial velocity, radial velocity and concentration simultaneously. Joint pdfs of concentration and radial velocity have symmetries in whole scales on the jet centerline. Correlation vanishing scales of the concentration and radial velocity are smaller than those of the concentration and axial velocity at the region off the jet centerline.

Sulfonated polyaniline (SPAn) was employed to incorporate photocatalytic molecules directly into a polyaniline (PAn) matrix. Photoinduced electron transfer between SPAn and the tris(2,2′-bipyridyl)ruthenium complex (Ru(bpy)3/2+) was studied for a Ru(bpy)3/2+-incorporated SPAn film in solutions containing viologens. The change in the spectrum of the film was observed by the illumination to the electrochemically reduced film under open circuit conditions in an aqueous solution at pH 2.5 containing methylviologen (MV2+). This is due to a photoelectrochromism, caused by the photooxidation of SPAn by the photoexcited Ru(bpy)3/2+. The film was hydrolyzed in the aqueous solution once the potential was swept above +1.2 V. Ru(bpy)3/2+ molecules were revealed to accelerate the hydrolysis of the SPAn backbone. Although the illumination to the electrochemically reduced film under open circuit did not seem to induce the hydrolysis under the present conditions, the fully oxidized film was photohydrolyzed by the illumination, leading to a decrease in the absorption corresponding to SPAn at the illuminated part. The photoelectrochromism and photohydrolysis of the film were discussed from a viewpoint of negative and positive image formation, respectively. © 2001 Elsevier Science B.V.

The axial velocity, radial velocity and concentration of a high Schmidt number matter were measured simultaneously in an axisymmetric turbulent jet. The diffusing fluid is a water solution of the commercial dye (Schmidt number Sc≃3 800), and an issuing Reynolds number is 6 400. A combined probe of a fiber optic concentration sensor and a X-type hot film was used to measure the axial velocity, radial velocity and concentration simultaneously. The normalized axial and radial mass flux show similar profiles. Eddy diffusivities are the function of onlyr/Lu(the radial distance normalized by the half width of axial mean velocity). The effect of the axial concentration gradient is dominant for the axial mass flux near the jet centerline, and also the effect of the radial concentration gradient becomes significant far from the jet centerline.

Copper catalysts supported on MFI-type metallosilicate were prepared and their activities for selective oxidation of NH3 were examined. Among the catalysts tested in this study, copper catalysts supported on MFI-type metallosilicate showed the highest activity. This catalyst selectively converted NH3 to N-2 at 250-400 degreesC in the presence of excess oxygen. The characterization of acidity and the effect of copper content revealed that active site of the catalyst in selective oxidation of NH3 was the copper supported on the strong acidic site of metallosilicate. From NH3-TPD, NH3-O-2 pulse reaction and FT-IR measurements, amino groups formed on the catalyst surface were found to be intermediates of the NH3 selective oxidation. The following mechanism for,the selective oxidation of NH3 was suggested; NH3 is first adsorbed on the Bronsted acid site of metallosilicate and then converted to NH4+. Secondly, dinitrogen group intermediate is formed by the oxidative dehydration of NH4+. Finally, dinitrogen group intermediate is dehydrated oxidatively to N-2.

Iridium catalyst supported on MFI-type metallosilicate with activation treatment in 10% H2O-N-2 at 700 degreesC was prepared and its catalytic activity for the selective reduction of NOx with hydrocarbons under oxgen rich conditions was investigated. The primary objective is the development of a catalyst system which reduce NOx and the emission of hydrocarbons at a wide temperature range. The two stage catalysts with activated iridium catalyst and Pt-Rh/Al2O3 (Three-way catalyst), were prepared and showed NOx reduction activity at a wide temperature range of 250-500 degreesC. Hydrocarbons were completely removed at higher temperatures than 300 degreesC. This system revealed high NOx reduction activity both a lean and stoichiometry atmosphere, and showed superior transient NOx reduction activity from lean to a stoichiometry atmosphere. The activated iridium catalyst showed a maximum NOx conversion of 70% at 400 degreesC in the actual exhaust gas of a lean burn gasoline engine. It is inferred that the activated iridium catalyst had sufficient NOx reduction activity and durability after aging treatment of a lean atmosphere at 660 degreesC and a rich atmosphere at 800 degreesC for a lean burn gasoline engine.

A DNA-polyaniline complex has been successfully prepared by the photopolymerization of dimeric aniline via photocatalytic reaction with Ru(bpy)(3)(2+) complex in the presence of DNA , a reaction which occurs, even in solution at pH 3.0-6.0, due to the specific local "lower-pH" environment provided by DNA.

Conductive polyaniline was successfully generated when Flemion film containing tris(2,2-bipyridyl)ruthenium complex (Ru(bpy)(3)(2+)) and methylviologen (MV2+) was illuminated in an acidic aqueous solution containing N-phenyl-p-phenylenediamine (PPD) and aniline or acetone. Aniline or acetone was employed to prepare PPD-incorporating particles in an acidic aqueous solution, which was important for the photopolymerization. The photopolymerization proceeded in the solution rather than on the film when aniline was employed at higher concentration. This is due to the release of Ru(bpy)(3)(2+) from the film by the ion-exchange reaction between Ru(bpy)(3)(2+) and protonated aniline. On the other hand, acetone molecules did not take part in the photopolymerization. Acetone enables PPD to be supplied near Ru(bpy)(3)(2+) in the film without the release of Ru(bpy)(3)(2+). Addition of acetone was revealed to be effective for the photopolymerization of aniline derivatives for the film from the viewpoint of image formation.

A Ru(bpy)(3)(2+)-based red-emitting diode with a fast turn-on response was fabricated by employing a novel, processable and water-soluble DNA-photopolymerized PAn complex containing Ru(bpy)(3)(2+).

Among the noble metal catalysts tested in the present study, iridium catalyst supported on MFI-type metallosilicate, which had been activated in 10% H2O-N2at 700 °C, showed the highest catalytic activity for the selective reduction of NOxwith hydrocarbon under oxygen rich condition. The conversion of NO into N2on the activated iridium catalysts was not affected by the presence of water vapor. The characterization by XRD, XPS and TEM revealed that the agglomerated Ir metal was formed in the iridium catalysts showing the high NOxreduction activity. From FT-IR and TPD measurements, -NO2or -ONO, and -CO formed on catalyst surface in NO + C3H6+ O2reaction were found to be intermediates of the selective reduction of NOx. On the basis of these results, it is inferred that the high NOxreduction activity of the activated iridium catalyst resulted from the presence of the active oxygen species on activated iridium catalyst which might react with NO and hydrocarbons to form reactive oxygenated intermediates.

The structurally ordered polymer. triphenylamine-pendant polypeptide (PATPA: poly[gamma-4-(N,N-diphenylamino-phenyl)-L-glutamine]) was prepared in order to obtain high hole mobility and high thermal stability. The hole mobility obtained for PATPA ica. 10(-5) cm(2)/Vsec) at room temperature is higher than that for poly/N-vinylcarbazole) (PVK) (ca. 10(-7) cm(2)/Vsec) or that of carbazole-pendant polypeptide (PCLG) (ca. 10(-8) cm(2)/Vsec). These results are supported by thermally stimulated current (TSC) measurements because the TSC can be correlated with the mobility. The glass-transition temperature (T-g) of PATPA was estimated to be about 130 degrees by differential scanning calorimetry (DSC). From these results, PATPA is an alternative candidate as a photoconductive polymer with high thermal stability and high hole mobility. The ordered structure along the main chain is thought to facilitate hole transport. (C) 2000 John Wiley & Sons, Inc.

The axial velocity and concentration of a high Schmidt number matter were measured simultaneously in an axisymmetric turbulent jet. The diffusing fluid is a water solution of the commercial dye (Schmidt number Sc 3800), and an issuing Reynolds number is 6300. A combined probe of a fiber optic concentration sensor and a sigle hot film was used to measure the axial velocity and the concentration simultaneously. The axial velocity and concentration power spectra show the lognormality in the scale region smaller than the integral scale of velocity. The decreases of the correlations of the axial velocity and the concentration are observed in the same region as the power region of the velocity spectra. And they have almost no correlation in the scale region smaller than that region.

Iridium catalysts supported on MFI-type metallosilicates with activation treatment in 10%H2O-N2 at 700 °C showed very high NOX reduction activity at 300-500 °C under oxygen rich condition. The activated catalyst showed stable NOX reduction activity in lean burn atmosphere with steam gas and rich atmosphere gas treatment and was durable to SO2-poisoning. This catalyst had stable NOX reduction activity in continuous treatment at 450 °C of lean burn gas atmosphere, but showed catalytic deactivation in continuous treatment over 500 °C of lean burn gas atmosphere. However , the activity of deactivated catalyst is easily regenerated by the lean/stoichiometry alternate gas treatment. Moreover, this catalyst showed stable NOX reduction activity of lean/stoichiometry alternate atmosphere gas treatment for 450 h. The characterization by XRD and XPS revealed that the reason of catalytic deactivation in continuous treatment of lean burn gas atmosphere was in the form of Ir oxide around the Ir-metal surface. Ir oxide around the Ir-metal surface is easily removed by the hydrocarbon treatment in the stoichiometry gas atmosphere.

Photorewritable conducting polyaniline (PAn) image was successfully obtained by the photopolyrmerization of aniline derivatives with Flemion polyelectrolyte composite film containing Ru(bpy)(3)(2+) and TiO2. The image can be erased and regenerated by consecutive photoreduction and photooxidation via photoinduced electron transfer for TiO2 and Ru(bpy)(3)(2+) in the polyelectrolyte composite film, respectively. These photoinduced reactions were considerably affected by the deaeration condition for the reaction solution. When the photooxidation and photoreduction were carried out in the reaction solution deaerated with O-2 and N-2, respectively, good reversibility was obtained on the present system. However, the decomposition of the PAn was observed by excessive photooxidation in the acidic aqueous solution due to the hydrolysis of the PAn. In order to prevent the PAn decomposition, photoredox reaction of the PAn polyelectrolyte composite film was investigated in dichloroethane containing CF3COOH and MeOH. Consequently, improvement of photoreduction efficiency, as well as inhibition for the decomposition reaction of the PAn polyelectrolyte composite film was obtained. (C) 2000 Elsevier Science Ltd. All rights reserved.

Photopolymerization of aniline and an aniline dimer was studied by illuminating a bilayer film composed of ruthenium bipyridyl complex (Ru(bpy)32+). Ruthenium trisbipyridyl complex was intercalated and aniline dimer was protonated in a hectorite clay in acidic aqueous solutions. Fluorescence photospectrometer was used to analyze the emission spectra of Ru(bpy)32+. Emission decay was calculated by single-photon counting method using the excitation wavelength of the isosbestic point. The complex showed a single exponential luminescence decay with lifetime characteristic of excited Ru(bpy)32+in aerated aqueous solution.

優れた光電特性を有する高分子材料を調製するため, カルバゾリル基を側鎖に導入したポリペプチド (ポリ {γ-[β-(N-カルバゾリル)-エチル]-Lグルタメート}) (PCLG) を合成した。α-ヘリックス構造を有する剛直な高分子であるポリペプチドは主鎖方向に大きな双極子モーメントを有するため, 成膜時に電場を印加することで主鎖を配向させることが可能である。この配向状態を誘電率より算出した配向係数を用いて評価し, 光電特性との相関について検討した。分子量の低いPCLGほど電場配向の影響を受けやすく, また配向性の増加に伴い高い光電流/暗電流比が得られた。このことは分子の規則的な配列が光電特性向上に有効であることを示唆している。PCLG電場配向膜は剛直な主鎖が電場配向されているため, 熱的な配向性の変化が起こりにくいと考えられる。100℃で2時間熱処理を行ったPCLGポーリング膜は処理前と同様な電気特性を示し, 良好な熱安定性を示すことが明らかとなった。

Iridium catalysts supported on MFI-type metallosilicates were prepared and their catalytic activity for the selective reduction of NOxwith hydrocarbons under oxygen rich condition was investigated. The as-prepared catalyst hardly reduces NOxto N2though it showed very high activity for the hydrocarbon conversion with oxygen. After subjecting the activation treatment in 10%H20-N2at 700 °C, on the other hand, the activated catalyst showed very high NOxreduction activity. The activated catalyst selectively and efficiently reduced NOxto N2with olefinic and aromatic hydrocarbons at 300-500 °C in the stoichiometric to lean conditions. The characterization by XRD and EXAFS revealed that the Ir species existed in the form of oxide (IrO2) and metal in the as-prepared and activated catalysts, respectively. In addition, H2-TPR measurement showed that the activated catalyst had active oxygen species on the Ir metal surface which was more reactive (reducible) than oxygen species on IrO2and bulky Ir metal. It was inferred that the high NOxreduction activity of the activated catalyst resulted from the presence of the active oxygen species which might react with hydrocarbons to form reactive oxygenated intermediates.

Photopolymerization of aniline derivatives was revealed to be induced by photoinduced electron transfer (PIET) between tris(2,2'-bipyridyl)ruthenium complex (Ru(bpy)32+) and electroactive molecule. Characterization of the polyaniline prepared should be necessary to compare its potential with chemically or electrochemically polymerized polyaniline. From the results of cyclic voltammetry (CV), IR and1H-NMR analysis, the polymer was identified as polyaniline. GPC analysis of photopolymerized polyaniline indicated that the polyaniline has molar mass of about several thousands. Further, an application of the present photopolymerized polyaniline system was also proposed. © 1999 Elsevier Science S.A. All rights reserved.

In this report, we present the new results of simultaneous measurements of the velocity and scalar quantity in an axisymmetric turbulent jet of the water solution of high Schmidt number matter. The diffusing fluid is a water solution of commercial dye (S(C) κ 3800), and an issuing Reynolds number is 6300. The new combined probe of a reflection type of fiber optic concentration sensor and an I-type hot film has been developed for the simultaneous measurement of the concentration and axial velocity. At first, we examined the interference effects between the fiber sensor and the hot film, and confirmed that the reliable data can be obtained when two probes are set at a distance of 0.3 mm which is smaller than the Taylor microscale of the velocity field(x/D ≥ 30). Then, we measured the concentration and axial velocity simultaneously. It is found that the correlation between the concentration and axial velocity has a positive value in a fully developed turbulent jet and that the turbulent axial mass flux on the jet centerline is in inverse proportion to the square of the downstream distance. The similarly of the radial profiles of the axial mass flux is also observed.

Carbazolyl groups pendant poly(glutamate) (PCLG) was prepared to analyze its charge-transport properties by employing mobility measurements and thermally-stimulated current (TSC) measurements. The mobility induced TSC (MITSC) model proposed by I.Chen was employed to evaluate the experimental TSC spectra with mobility results. Simulated MITSC spectra showed good agreement in its peak temperature with experimental TSC spectra for PCLG. This suggests that the carrier transport followed the trap-limited mechanism estimated by the mobility results. Further, the peaks in experimental TSC spectra appeared over the same temperature range as that in thermally-stimulated polarization current (TSPC) spectra. Since the TSPC spectra were found to be correlated with the dielectric tan delta spectra for PCLG, the peaks in TSPC spectra are attributed to the side-chain relaxation for PCLG. Therefore, the similarity between TSPC and TSC spectra indicates that the charge-transport mechanism for PCLG was considerably affected by side-chain relaxation for PCLG;, which would vary the energy state of trap sites and effectively reduces the energy for the release of the carriers trapped on the illuminated surface. (C) 1999 John Wiley & Sons, Inc.

Photorewritable conducting polyaniline image was successfully obtained by the photopolymerization of aniline derivatives for Flemion composite film containing Ru(bpy)3 2+ and TiO2. The image can be erased and regenerated by consecutive photoreduction and photooxidation via photoinduced electron transfer with TiO2 and Ru(bpy)3 2+ in the composite film. These photoinduced reactions were considerably affected by the deaeration condition for the reaction solution. When photooxidation and photoreduction were carried out in the reaction solution deaerated O2 or N2 respectively, good reversibility for photoredox reaction was obtained on the present system.

Hole transport molecules pendant polypeptide was synthesized in order to investigate the photoconductive property in the lyotoropic liquid crystalline polypeptide. By the application of an electric field to the liquid crystalline cell, the schlieren structure indicating the nematic structure was observed in the cell by using a polarized optical micrograph. Relatively high drift mobility of ca. 10-3 (cm2/V·s) and photoconductivity were obtained in the nematic liquid crystalline cell. Consequently, we conclude that highly ordered intra and interchain structure is effective for the photoconductive and charge carrier transport properties.

Photopolymerization of aniline derivatives was revealed to be induced by photoinduced electron transfer (PIET) between the tris(2,2′-bipyridyl)ruthenium complex [Ru(bpy)32+] and electroactive molecules. Since the initial photopolymerization reaction depended on PIET between Ru(bpy)32+ and N-phenyl-p-phenylenediamine (PPD), the effect of pH of the polymerization solution on the PIET was investigated to improve the efficiency of the photopolymerization reaction. At lower pH, the quenching reaction of [Ru(bpy)32+]* by PPD proceeded with low efficiency due to electrostatic repulsion between molecules concerning the PIET. This was clarified by comparison with the results concerning the photochemistry in a higher pH solution. On the other hand, a lower pH should be required to induce the propagation because a lower pH inhibited the deprotonation of both aniline derivative and growing poly(aniline) chain. From the detailed analyses for both initial and propagation reactions, the increase in ionic strength was revealed to be a solution to improve the photopolymerization efficiency even in low pH.

Polypeptide having carbazolyl groups (poly-gamma-[2-(9-carbazolyl) ethyl]-L-glutamate) (PCLG) was synthesized in order to prepare a lyotropic liquid crystalline cell with higher mobility. Typical Time-Of-Flight (TOF) method was employed to analyze its charge transport property. Transient photocurrent for the liquid crystalline cell showed nondispersive transport property. Relatively high drift mobility of ca.10(-3) (cm(2)/V.s) was obtained in the cell composed of PCLG with both intra and interchain ordered structure.

Conducting polymers are promising materials which show attractive electric and optical properties with potential importance in advanced technologies. Electrochromism is one of the noteworthy characteristics of conducting polymers and is effective in forming conducting polymer images and patterns on an electrode. Space selective image formation is also possible without an electrode by means of the combination of photoinduced electron transfer reaction with electrochromism. This has potential as a novel method of surface modification for any geometry in any place and for micropatterning. In this article, some recent aspects of (1) the electrochromism of conducting polymers and (2) the polymerization and electrochromism of conducting polymers induced by photoillumination leading to image formation are considered from the materials viewpoint. Further, possible future applications for these materials and systems are commented upon.

Photo-oxidation (photoelectrochromism) of poly(aniline) was performed using photoinduced electron transfer between Ru complex (Ru(bpy)(3)(2+)) and methylviologen molecules. Especially, effect of electrode structure on the photoelectrochromism was at first analysed in solution system. The electrode structure to increase the probability that poly(aniline) and Ru(bpy)(3)(2+) came into contact or very nearly so was effective to proceed the photoelectrochromism. Further, employment of poly(ethylene glycol) (PEG, Mw = 400) as additive into Flemion matrix revealed to enable the present photoelectrochromism even in all solid state. Effect of PEG addition was also discussed. (C) 1998 Published by Elsevier Science Ltd. All rights reserved.

A solid state photoelectrochemical bilayer cell was fabricated with Ru(bpy)(3)(2+) + PEG + Nafion layer and MV2+ pendant polysiloxane (PSiO-MV2+) layer. The effect of PEG addition on the photoelectric properties was discussed especially with charge transport in the Nafion layer. Increase in photoelectric properties produced by PEG addition to the Nafion layer was found for the solid state cells. Solid state voltammetry indicated that this increase was attributed to the increase in D-app for Ru(bpy)(3)(2+) in the Nafion layer. From emission lifetime of Ru(bpy)(3)(2+) in the Nafion film, spatial distribution and local motion of the Ru(bpy)(3)(2+) molecules in the Nafion film were estimated to analyse charge transport process, physical diffusion and/or electron hopping, in detail. As a result, PEG addition would affect the electron hopping reaction between Ru(bpy)(3)(2+) and Ru(bpy)(3)(3+) molecules in the Nafion film, resulting in the increase in photoelectric properties for the cell containing PEG. (C) 1998 Published by Elsevier Science Ltd. All rights reserved.

Electropolymerization of aniline was carried out in a non-aqueous solution of 1,2-dichloroethane (DCE) without protic acid at temperatures ranging from 248 to 298K. The resulting poly(aniline) deposit on the electrode showed higher conductivity with decreasing electropolymerization temperature. The polymer prepared at higher temperatures had higher molar mass, which was expected to be effective for intrachain conductivity. However, this was not the case with the branched structure and/or discontinuity of the π-conjugated system found by FT-IR and NIR measurements. On the contrary, a morphological difference in the deposit was clearly found on varying the electropolymerization temperature. This difference resulted from the initial stage of the polymer deposition on the electrode, concerned with nucleation. The difference in conductivity for the poly(aniline) deposit with varying electropolymerization temperature is discussed in terms of the polymer chain structure and the morphology of the deposit. © 1997 Elsevier Science S.A.

The preparation of two copolymers of vinylferrocene and 4-(vinylpyridine) containing a few per cent of ferrocene groups and having molar masses of 2.3 × 105 and 2.4 × 104 g mol-1 is described. The copolymers were dissolved in aqueous hydrochloric acid, where their electro-oxidation was examined by voltammetry at rotating disk electrodes. Severe adsorption on the electrode surface of the higher molar mass copolymer interfered with the evaluation of its diffusion coefficient, but values were obtained for the lower molar mass copolymer. The effects of pH, ionic strength and electrostatic binding of multiply charged counterions on the diffusion of both copolymers were examined. The uncertainties inherent in the use of electrochemical methods to evaluate apparent diffusion coefficients of polymers in mixtures with varying molar masses are pointed out.

Aniline is photopolymerized by illuminating a bilayer electrode composed of tris(2,2′-bipyridyl)ruthenium complex [Ru(bpy)32+] incorporated Nafion film and methylviologen pendant poly(siloxane) (PSiO-MV2+) film in aniline solution in the presence of N-phenyl-p-phenylenediamine (PPD); the role of PPD on photopolymerization of aniline is also discussed.

カルバゾリル基を側鎖に約50%導入したポリペプチド (ポリ {γ-[β-(N-カルバゾリル) エチル]-L-グルタメート/メチル-L-グルタメート} コポリペプチド) (PC50LG) を合成した。このポリペプチドにシアニン色素を分散させることによりα-ヘリックスに相当するモル楕円率の増加が認められた。側鎖カルバゾリル基のカルバゾール環のπ電子とシアニン色素の共役π電子との相互作用による主鎖構造または側鎖配向性の変化に基づくものと考えられる。シアニン色素の吸収領域においても誘起円偏光二色性 (ICD) が認められ, しかもこのICDの形状, 大きさはシアニン色素のメチン鎖長に大きく依存した。これらの結果とシアニン色素分子長ならびにPC50LGの推定分子構造から, シアニン色素はポリペプチドのα-ヘリックス上でカルバゾリル基と相互作用し, シアニン色素の鎖長に依存したコンフォメーションをとっていることが考えられる。さらに, シアニン色素分散PC50LGの光導電性について検討を行った結果, シアニン色素のICDが大きく, 相互作用の強いNK-76・PC50LG系で, PC50LG単独系に比べ約10倍大きな光電流感度が得られた。この光電流の増加についてシアニン色素・PC50LG複合体の構造を含めて議論した。

The initial formation of poly(aniline) and its derivatives was investigated for the electropolymerization of anilines in several non-aqueous solutions without proton donor to prepare the films effectively. In this study, 1,2-dichloroethane, acetonitrile, propylene carbonate and tetrahydrofuran were employed as solvent. The donor number of the solvent affects the deprotonation of the cation radical of the monomer formed, and the dimer and products, and the dielectric constant of the solvent affects chain propagation during the electropolymerization of anilines respectively. 1,2-Dichloroethane is revealed to be a more effective solvent than the others used in this study to prepare electroactive and soluble poly(aniline)s with head-to-tail structure.

This paper concerns photoinduced ionic conductivity response in the polymer electrolyte, which is synchronized with reversible photochromic chelation of spiropyran and a di-valent cation. The polymer having (methoxy)spiropyran groups, which is expected to show photochromic chelation with di-valent cations in the solid state upon uv irradiation, was synthesized and complexed with ZnCl2. Reversible photoinduced ionic conductivity response was found in the resulting polymer electrolyte and was synchronized with reversible photochromic chelation. The photochromic chelation was revealed to decrease the carrier number in the polymer electrolyte and consequently to decrease the ionic conductivity. Further, the present photochromic chelation was easily suppressed by vis. illumination, resulting in the ionic conductivity being restored to the initial value. © 1995.

A photoelectrochemical response was found for a methyl viologen pendant polysiloxane film coated on an indium tin oxide (ITO) electrode dipped in an aqueous electrolyte solution containing O2. Both the current direction (cathodic or anodic) and the extent of the photoresponse depended on the substitutional ratio of methyl viologen on the polymer chain. This behavior was not explained by simple photoinduced electron transfer from the excited cation radical of the methyl viologen to O2. The mechanism is discussed for steady state 02 and cation radical concentrations and with respect to O2 permeability in the polysiloxane film.

A solid-state photoelectrochemical device was fabricated with a poly-siloxane pendant tris(2,2ʹ -bipyridyl) ruthenium complex (Formula Presented) as a photosensitizer layer and a polysiloxane pendant methylviologen [PSiO–MV2+] as an electron acceptor layer. In the dark, the (Formula Presented)Ag solid-state cell showed rectification characteristics. Photocurrent was obtained in the bilayer solid-state cell upon illumination of visible light, which was caused by the photoexcitation of the (Formula Presented) and successive electron transfer to the MV2+. The short-circuit photocurrent of 0.485 μA·cm–2 was obtained with the intensity of illumination of 34 mW·cm–2. © 1994 Japanese Journal of Applied Physics. All rights reserved.

ポリアニリン膜 [PAn] とトリス (2, 2'-ビピリジル) ルテニウム錯体 [Ru (bpy) <SUB>3</SUB><SUP>2+</SUP>] を静電的に取り込んだナフィオン膜を組み合わせることによって, ITO/PAn/Nafion+Ru (bpy) <SUB>3</SUB><SUP>2+</SUP>二層膜電極を作製し, メチルビオロゲン [MV<SUP>2+</SUP>] を含んだ酸性水溶液中においてその光電気化学的な特性を検討した。ITO/PAn/Nafion+Ru (bpy) <SUB>3</SUB><SUP>2+</SUP>二層膜電極への光照射により, 閉回路時には還元電流の増加, 開回路時にはPAnのバイポーラロン状態の形成にもとつく吸収スペクトル変化が認められた。これらの結果は, 励起状態のRu (bpy) <SUB>3</SUB><SUP>2+*</SUP>からMV<SUP>2+</SUP>への光誘起電子移動を利用することによってPAnの光酸化およびエレクトロクロミズムを発現できることを示している。さらに, この系は, 光酸化と電解還元を可逆的に行うことができるため, 書換型の光画像記録素子への応用が期待できることを示した。

Photoresponse in ionic conductivity has been realized in the solid polymer electrolytes, consisting of poly[(ω‐hydroxy) oligo(oxyethylene) methacrylate] [P(MEO)OH] or poly[(MEO)OH‐co‐butyl methacrylate] (PBMA), spiropyran derivative (SP) and LiClO4. SP showed reversible isomerization upon photoirradiation in these films. The ionic conductivity in these films decreased upon ultraviolet light (UV) irradiation and subsequently increased upon visible light (Vis) irradiation. The interaction between photoisomerized merocyanine form (PMC form) and the hydroxyl group on the polymer side chain was confirmed by an IR shift assignable to OH stretching vibration. From DSC thermograms, the change of ionic conductivity was revealed to be considerably affected by this interaction and attributed to reversible photoisomerization of SP. Reversibility of ionic conductivity was improved in copolymer P[(MEO)OH‐co‐BMA] in comparison with that in P(MEO)OH. Copyright © 1993 John Wiley & Sons, Ltd.

The copolymer composed of (ω-methoxy) oligo (oxyethylene) methacrylate and spiropyran methacrylate has been prepared. Spiropyran group showed reversible isomerization in this polymer film upon photoirradiation. The ionic conductivity in this film doped with LiClO<SUB>4</SUB> gradually decreased upon UV irradiation and subsequently increased upon Vis irradiation. Reversible change of ionic conductivity by photoirradiation is in good correlation with the change in absorbance assignable to photomerocyanine-form (PMC-form). This change is revealed to be attributed to the aggregation between dyes (PMC-form and/or spiro-form). The glass transition temperature (<I>T<SUB>g</SUB></I>) for this film increased by UV irradiation. This behavior indicates that the aggregation between dyes acts as quasi-crosslinking point in solid matrix. The progress of this aggregation brought about the change in ionic mobility. Thus, the ionic conductivity can becontrolled by photoirradiation in the solid polymer electrolyte.