Updated on 2022/05/26

写真a

 
SUGA, Takeo
 
Affiliation
Faculty of Science and Engineering, School of Advanced Science and Engineering
Job title
Associate Professor

Concurrent Post

  • Faculty of Science and Engineering   Graduate School of Advanced Science and Engineering

Research Institute

  • 2021
    -
    2022

    リサーチイノベ オープンイノベーション推進セクション   兼任センター員

  • 2020
    -
    2022

    理工学術院総合研究所   兼任研究員

Education

  • 2004.04
    -
    2007.03

    Waseda University   Graduate School, Division of Science and Engineering   Applied Chemistry  

  • 2004.04
    -
    2007.03

    Waseda University   Graduate School, Division of Science and Engineering   Department of Applied Chemistry  

  • 2003.04
    -
    2004.03

    Waseda University   Graduate School, Division of Science and Engineering   Applied Chemistry  

  • 2003.04
    -
    2004.03

    Waseda University   Graduate School, Division of Science and Engineering   M. Eng., Department of Applied Chemistry  

  • 1999.04
    -
    2003.03

    Waseda Univeristy   Faculty of Science and Engineering   Applied Chemistry  

Degree

  • 2007.03   Waseda University   Doctor of Engineering

Research Experience

  • 2021.04
    -
    Now

    Waseda University   Department of Applied Chemistry, School of Advanced Science and Engineering   Associate Professor

  • 2016.04
    -
    2021.03

    Waseda University   Department of Applied Chemistry   Assistant Professor, tenured

  • 2012.04
    -
    2016.03

    Waseda University   Waseda Institute for Advanced Study   Assistant Professor

  • 2010.04
    -
    2012.03

    Waseda University   Research Institute for Science and Engineering   Research Assistant Professor

  • 2009.09
    -
    2010.03

    Waseda University   Graduate School of Advanced Science and Engineering   Junior Researcher

  • 2008.09
    -
    2009.08

    Waseda University   Graduate School of Advanced Science and Engineering   Research Associate

  • 2007.04
    -
    2008.08

    Virginia Tech   Department of Chemistry   Post-doctoral fellow

  • 2005.04
    -
    2007.03

    Waseda University   Department of Applied Chemistry   Research Associate

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Professional Memberships

  •  
     
     

    Research Group on Inorganic Polymers, SPSJ

  •  
     
     

    Research Group on Supramolecular Polymers, SPSJ

  •  
     
     

    RadTech Japan

  •  
     
     

    ACS, PMSE Division

  •  
     
     

    ACS, POLY Division

  •  
     
     

    American Chemical Society

  •  
     
     

    The Electrochemical Society of Japan

  •  
     
     

    The Chemical Society of Japan

  •  
     
     

    The Society of Polymer Science of Japan

▼display all

 

Research Areas

  • Polymer chemistry   Controlled polymerization, Microphase-separation, In-situ reaction

  • Organic functional materials   Solar cells, Conjugated polymers, Charge-transport materials

  • Polymer materials   Polymer coating, polymer network, UV curing

Research Interests

  • Polymer Synthesis, Functional Polymers, Organic Electronic Device

  • Polymer Synthesis, Functional Polymers, Organic Electronic Device, Energy-Conversion and -Storage

Papers

  • Optimizing the Interdomain Spacing in Alicyclic Polythiourea toward High-Energy-Storable Dielectric Material

    Yang Feng, Liuqing Yang, Guanghao Qu, Takeo Suga, Hiroyuki Nishide, George Chen, Shengtao Li

    MACROMOLECULAR RAPID COMMUNICATIONS   41 ( 13 )  2020.07  [Refereed]

     View Summary

    Organic dielectric materials have been widely developed and investigated for energy storage capacitors. However, challenges remain in terms of the relatively low dielectric constant and energy density. Enhancing the dipolar polarization to increase the dielectric constant is considered to be an effective way to improve the energy density of polymer dielectrics. Herein, enlightened by the chain-packing structure that affects the dipolar relaxation behavior, a simple and low-cost approach is proposed to tailor the interdomain spacing in an alicyclic polythiourea (PTU) by changing quenching temperatures and further facilitate the dipolar polarization. It is found that the large interdomain spacing is beneficial to promote the localized motion of segmental chains in amorphous regions, but at the same time inevitably reduces the dipole density. Therefore, in order to achieve the highest dielectric constant in the PTU, there is an optimal value for the interdomain spacing. It is worth noting that the dielectric constant of PTU increases from 5.7 to 10, and thus the energy density increases by 53% to 16.3 J cm(-3). It proposes a simple and feasible strategy to further improve the energy density through optimizing the interdomain spacing toward high-energy-storable dielectric material.

    DOI PubMed

  • Phenolic antioxidant-incorporated durable perovskite layers and their application for a solar cell

    Koki Suwa, Takeo Suga, Kenichi Oyaizu, Hiroshi Segawa, Hiroyuki Nishide

    MRS COMMUNICATIONS   10 ( 2 ) 312 - 316  2020.06  [Refereed]

     View Summary

    The incorporation of small amounts of phenolic antioxidants, such as 2,6-di-tert-butyl-4-cresol and pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], into photovoltaic organo-lead halide perovskite layers significantly suppressed the degradation of the perovskite compounds via light irradiation in the presence of ambient oxygen. While the facile incorporation of the antioxidants did not decrease both the quality of the formed perovskite crystal grains and the photovoltaic conversion performance of the cells, it enhanced the antioxidizing property and water repellency of the perovskite layer owing to the elimination of superoxide anion radical and hydrophobic molecular structure and improved the durability of the cells.

    DOI

  • Facile Synthesis of Isotactic Polyacrylonitrile via Template Polymerization in Interlayer Space for Dielectric Energy Storage

    Yu Wang, Ryota Nakamura, Takeo Suga, Shengtao Li, Yoshimichi Ohki, Hiroyuki Nishide, Kenichi Oyaizu

    ACS APPLIED POLYMER MATERIALS   2 ( 2 ) 775 - 781  2020.02  [Refereed]

    Authorship:Corresponding author

     View Summary

    Isotactic polyacrylonitrile (iso-PAN) is synthesized via template polymerization using the two-dimensional layered space of a CoCl2 crystal as a template. Isotacticity of polyacrylonitrile reaches a meso/meso triad = 93% (mm = 0.93), which indicates a superior packing of polymer chains, leading to a high breakdown strength. Tacticity enhancement is correlated with the interatomic (metal-metal) distance of template -layered crystals. Due to a large dipole moment (4.3 D) of nitrile group and a high stereoregularity, iso-PAN demonstrates a high discharge energy density of 6.7 J/cm(3) at 660 MV/m, nearly six times that of atactic polyacrylonitrile (ata-PAN) and biaxially oriented polypropylene (BOPP), a commercially available dielectric polymer film. Moreover, it exhibits a charge-discharge efficiency of ca. 90% in a wide applied electric field range, which is higher than the efficiencies of ata-PAN and BOPP. These results suggest that iso-PAN, exhibiting a large dipole moment and high stereoregularity, is a promising candidate for high energy density and low loss capacitor dielectrics.

    DOI

  • Tuning Conformational H-Bonding Arrays in Aromatic/Alicyclic Polythiourea toward High Energy-Storable Dielectric Material

    Yang Feng, Yui Hasegawa, Takeo Suga, Hiroyuki Nishide, Liuqing Yang, George Chen, Shengtao Li

    MACROMOLECULES   52 ( 22 ) 8781 - 8787  2019.11  [Refereed]

    Authorship:Corresponding author

     View Summary

    Polythioureas (PTUs) have been investigated as a dielectric material for an energy-storable capacitor in both experimental and computational approaches. However, the effect of dipolar polarization, closely associated with conformational H-bonding arrays, on dielectric properties under the operating frequency has never been studied in PTUs. Here, a series of PTUs with different spacers and additional dipoles are synthesized to explore the influence of conformations in thiourea units on their dielectric properties. The additional dipolar substituent (-COOH) contributes to a high dielectric constant, while accompanying a remarkable dielectric loss. Alternatively, a random copolymer is prepared to adjust the -COOH content, which displays a high dielectric constant and a suppressed dielectric loss. However, it requires strict control of the segmental ratio to meet the energy-storage demand. A neat alicyclic PTU with a flexible cyclohexyl spacer also exhibited a high dielectric constant and a low dielectric loss because of its rich trans/trans conformation, which brings about an increasing effective dipole moment per unit volume. Meanwhile, it retains high breakdown strength, thus leading to high electric energy density (U-e approximate to 10 J/cm(3)). These results suggest that tuning conformational H-bonding arrays based on molecular design is a more effective way to improve the dielectric properties of PTUs toward a very high energy storable material.

    DOI

  • Perovskite/TiO2 Interface Passivation Using Poly(vinylcarbazole) and Fullerene for the Photovoltaic Conversion Efficiency of 21%

    Wataru Okada, Takeo Suga, Kenichi Oyaizu, Hiroshi Segawa, Hiroyuki Nishide

    ACS APPLIED ENERGY MATERIALS   2 ( 4 ) 2848 - 2853  2019.04  [Refereed]

     View Summary

    Poly(vinylcarbazole) (PVCz) dispersed the typical fullerene derivative, PCBM, well in its solution, which was then coated onto a mesoporous titanium oxide (TiO2) layer. PVCz served as a scaffold to fix PCBM homogeneously and to prevent its elution out upon the following perovskite layer formation. A series of perovskite cells were fabricated upon the PVCz/PCBM-modified TiO2 layer. Many of the cells were characterized by a photovoltaic conversion efficiency of >20%, and the top cells had an efficiency of 21.1% (with an average of 21.0%). Fluorescence decay from the perovskite layer of the cell was unchanged with the PVCz/PCBM modification, suggesting an efficient charge transport to the electron-transporting layers. On the other hand, the PVCz/PCBM modification or passivation significantly reduced electroluminescence intensity under an inverse bias application, supporting an efficient suppression of carrier recombination at the TiO2 and perovskite interface.

    DOI

  • Poly(1,4-di(2-thienyl))benzene Facilitating Complete Light-Driven Water Splitting under Visible Light at High pH

    Kouki Oka, Kanako Noguchi, Takeo Suga, Hiroyuki Nishide, Bjorn Winther-Jensen

    ADVANCED ENERGY MATERIALS   9 ( 6 )  2019.02  [Refereed]

     View Summary

    The recent discovery that metal-free polyterthiophene (PTTh) prepared by iodine-vapor-assisted polymerization (IVP) can catalyze the hydrogen evolution reaction (HER) when illuminated, and this light-enhanced electrolysis expresses a non-Nernstian relation with pH, provides the foundation for further improvement of the photovoltage of the reaction by engineering the band structure of the light-absorbing polymer. Deviating from an all-thiophene backbone, using poly(1,4-di(2-thienyl))benzene (PDTB) lowers the highest occupied molecular orbital level by approximate to 0.3 eV compared with polythiophene, and PDTB simultaneously maintains the photoelectrocatalytic properties without an all-thiophene backbone, resulting in very high conversion rate of 600 mmol(H-2) h(-1) g(-1) at 0 V versus the reversible hydrogen electrode (RHE) at pH 11. PDTB shows the same non-Nernstian behavior as PTTh with increasing onset potential (versus RHE) at higher pH, and the open circuit potential on PDTB under visible light reaches 1.4 V versus RHE at pH 12. The PDTB photocathode thus produces a photovoltage above the theoretical potential for the complete water-splitting (1.229 V) and is indeed able to produce hydrogen in a one-photon-per-electron light-driven water splitting setup with MnOx as the anode at a rate of 6.4 mmol h(-1) g(PDTB)(-1).

    DOI

  • How to Install TEMPO in Dielectric Polymers-Their Rational Design toward Energy-Storable Materials

    Yang Feng, Takeo Suga, Hiroyuki Nishide, Yoshimichi Ohki, George Chen, Shengtao Li

    MACROMOLECULAR RAPID COMMUNICATIONS   40 ( 4 ) 1800734(1) - 1800734(6)  2019.02  [Refereed]

     View Summary

    Polar groups and the charge-transport capability play significant roles in the dielectric properties of organic polymers, and thus influence the electric energy density upon application as a capacitor material. Here, the dielectric properties and electric conductivity of a series of polymers containing 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) radicals are investigated. The neat radical polymer poly(TEMPO methacrylate) (PTMA) has a high dielectric constant but poor breakdown strength. Poly(methyl methacrylate) (PMMA) is introduced as an insulating polymer with high resistivity on breakdown, along with molecular design of PTMA. Copolymers of TEMPO methacrylate and methyl methacrylate, P(TMA-r-MMA), exhibit high breakdown strengths but low dielectric constants. PMMA blended with TEMPO exhibits the highest electric energy density of 7.4 J cm(-3) (that of PTMA is 0.48 J cm(-3) as a control), with both a high dielectric constant (approximate to 6.8) and a high breakdown strength (approximate to 500 MV m(-1)). It benefits from long-range but not bulk charge transport in the blends, which is different from the bulk charge transport in PTMA and the short-range charge transport in P(TMA-r-MMA). These results indicate that the TEMPO moiety located in the high breakdown matrix leads to a high energy-storage density in the capacitor.

    DOI PubMed

  • Light-assisted electrochemical water-splitting at very low bias voltage using metal-free polythiophene as photocathode at high pH in a full-cell setup

    Kouki Oka, Orie Tsujimura, Takeo Suga, Hiroyuki Nishide, Bjorn Winther-Jensen

    ENERGY & ENVIRONMENTAL SCIENCE   11 ( 5 ) 1335 - 1342  2018.05  [Refereed]

     View Summary

    We report the use of polyterthiophenes (PTTh) as a rare, combined light-harvester and catalyst for the hydrogen evolution reaction at high pH. Illuminated PTTh in combination with a MnOx anode in a two-electrode setup exhibited stable water-splitting at a bias-potential of only 0.3 V at pH 12. This confirms that PTTh used as photocathode can produce photovoltages of at least 900 mV for the hydrogen evolution reaction at high pH and is therefore a suitable match for traditional water-oxidation catalysts such as MnOx, CoOx, and RuOx. Films of PTTh were fabricated using a novel, metal-free method where iodine vapor is used as oxidant; thus, previously observed interference from metal residuals was omitted and thereby a gravimetric photo electrocatalytic conversion rate of 330 mmol(H-2) h(-1) g(-1) was achieved in phosphate buffer (pH 7) at 0 V vs. RHE. A striking property of this new strand of polythiophene was an "inverse" correlation (compared to that predicted using the Nernstian relationship) between the onset potential for the light-assisted water reduction reaction and pH: the potential (vs. RHE) required for a given current was more positive at higher pH, which is not observed for other (photo-) electrocatalytic materials, and indicates that the charge neutralization of PTTh (rather than the pH) guides the onset potential.

    DOI

  • Ambient-Light-Promoted Three-Component Annulation: Synthesis of Perfluoroalkylated Pyrimidines

    Rui Wang, Wei Guan, Zheng-Bo Han, Fushun Liang, Takeo Suga, Xihe Bi, Hiroyuki Nishide

    ORGANIC LETTERS   19 ( 9 ) 2358 - 2361  2017.05  [Refereed]

     View Summary

    An ambient-light-promoted and,metal-free three-component reaction of active methylene compounds perfluoroalkyl iodides, and guanidines/amidines is reported: This constitutes a powerful method to prepare prfluoroalky-lated pyrinudines with mild reaction Conditions, broad substrate scope, excellent functional group tolerance, and simple operation. A radical/polar mechanism involving the formation of a halogen-bond adduct and radical cross-coupling is proposed.

    DOI PubMed

  • Quantifying TEMPO Redox Polymer Charge Transport toward the Organic Radical Battery

    Christoffer Karlsson, Takeo Suga, Hiroyuki Nishide

    ACS APPLIED MATERIALS & INTERFACES   9 ( 12 ) 10692 - 10698  2017.03  [Refereed]

     View Summary

    To, design new and better organic active battery materials in a rational fashion, fundamental parameters of the charge transport must be studied. Herein we report on the electronic conductivity by electron diffusion in a TEMPO-containing redox polymer, and the reorganization energy of the TEMPO self exchange in an organic solvent is determined for the first time. The electronic conductivity was 8.5 mu S/cm at E-0 and corresponded to a redox hopping mechanism. The apparent electron diffusion coefficient was 1.9 x 10(-9) cm(2)/s at room temperature, and at short times the ion diffusion was limiting with a diffusion coefficient of 6.5 x 10(-10) cm(2)/s. The reorganization energy was determined to be 1.01 eV, indicating a rather polar chemical environment for the TEMPO groups. The implications for the usage of this type of materials in organic energy storage are discussed. As conductivity through 10 gm was demonstrated, we show that, if sufficient swellability can be ensured) charge can be transported through several micrometer thick layers in a battery electrode without any conducting additive.

    DOI PubMed

  • Simultaneous visualization of oxygen partial pressure, current density, and water droplets in serpentine fuel cell during power generation for understanding reaction distributions

    Kazuhiro Takanohashi, Takeo Suga, Makoto Uchida, Toshihide Ueda, Yuzo Nagumo, Junji Inukai, Hiroyuki Nishide, Masahiro Watanabe

    JOURNAL OF POWER SOURCES   343   135 - 141  2017.03  [Refereed]

     View Summary

    Understanding the reaction distributions inside a polymer electrolyte fuel cell (PEFC) is essential for the higher performance and durability. We have developed a new see-through cell and visualized the distributions of oxygen partial pressure and current density inside a running PEFC at the temperature of 40 and 80 degrees C and the relative humidity of 53%. The oxygen utilization was changed from 0% to 80% by changing the current density. At higher oxygen utilizations, the current density was higher and therefore the water generation. Generated water droplets in the flow channel were also visualized, allowing for the simultaneous visualization of the distribution of the oxygen partial pressure, current density, and water droplets. By combining the observations of all three parameters, the reactions inside a membrane electrode assembly were discussed. (C) 2017 Elsevier B.V. All rights reserved.

    DOI

  • Unique gradient nanostructure formation in photo-cured coatings via photo-driven controlled radical polymerization

    Takeo Suga, Kenta Minamibayashi, Hiroyuki Nishide

    ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY   251  2016.03

  • Visualization of Oxygen Partial Pressure at Gas Diffusion Layer inside Polymer Electrolyte Fuel Cell during Cold Startup

    Nagase Katsuya, Uchida Makoto, Nagumo Yuzo, Suga Takeo, Inukai Junji, Nishide Hiroyuki, Watanabe Masahiro

    Abstract of annual meeting of the Surface Science of Japan   36 ( 0 )  2016

    CiNii

  • Unraveling Inter- and Intrachain Electronics in Polythiophene Assemblies Mediated by Coordination Nanospaces

    Michael W. A. MacLean, Takashi Kitao, Takeo Suga, Motohiro Mizuno, Shu Seki, Takashi Uemura, Susumu Kitagawa

    ANGEWANDTE CHEMIE-INTERNATIONAL EDITION   55 ( 2 ) 708 - 713  2016.01  [Refereed]

     View Summary

    Strong interchain interactions render unsubstituted polythiophene un-fusible, non-melting, and insoluble. Therefore, control of the packing structure, which has a profound effect on the optical and electronic properties of the polymer, has never been achieved. Unsubstituted polythiophene was prepared in the one-dimensional channels of [La(1,3,5-benzenetrisbenzoate)](n), where polymer chains form unprecedented assembly structures mediated by the host framework. It is noteworthy that the emission and carrier transport properties were drastically changed by varying the number of chains within a particular assembly. The response of the composite to additional guests is also examined as a method to use the composites as low-concentration sensors. Our findings show that the encapsulation of polymer chains in host materials is a facile method for understanding the intrinsic properties of conjugated polymers, along with controlling and enhancing their functions.

    DOI

  • "Click" Incorporation of Radical/Ionic Sites into a Reactive Block Copolymer: A Facile and On-Demand Domain Functionalization Approach toward Organic Resistive Memory

    Takeo Suga, Kohei Aoki, Toshiaki Yashiro, Hiroyuki Nishide

    MACROMOLECULAR RAPID COMMUNICATIONS   37 ( 1 ) 53 - 59  2016.01  [Refereed]

     View Summary

    Reversible addition-fragmentation chain transfer polymerization yields reactive block copolymers bearing the pentafluorophenyl ester (PFPA) group, and subsequent Click amidation using 2,2,6,6-tetramethylpiperidine-N-oxyl- and imidazolium-functionalized primary amines produces the corresponding functional block copolymers, leading to installation of statistical radical-and ionic sites into the PFPA segment. The monolayered thin film devices fabricated using the obtained block copolymers exhibit repeatable switching of electric conductivity (on/off ratio > 10(3)) under a bias voltage, which reveals that the coexistence of radicals and ions in the same spherical domain of the copolymer layer is a prerequisite for repeatable switching memory.

    DOI

  • Visualization of Oxygen Partial Pressure and Numerical Simulation of a Running Polymer Electrolyte Fuel Cell with Straight Flow Channels to Elucidate Reaction Distributions

    Katsuya Nagase, Haruki Motegi, Masakazu Yoneda, Yuzo Nagumo, Takeo Suga, Makoto Uchida, Junji Inukai, Hiroyuki Nishide, Masahiro Watanabe

    CHEMELECTROCHEM   2 ( 10 ) 1495 - 1501  2015.10  [Refereed]

     View Summary

    Visualization of the oxygen partial pressure (p(O(2))) was performed at the surface of a gas diffusion layer (GDL) and the upper part of the gas-flow channel of the cathode of an operating polymer electrolyte fuel cell (PEFC) with straight flow channels by using an oxygen-sensitive luminescent dye film. The gradient of p(O(2)) inside a channel was clearly observed, even on the GDL surface across the channel. A numerical simulation was performed to understand the reaction distributions inside the PEFC. By visualization and numerical simulation, the distributions of p(O(2)), the current density, water concentration, and temperature in the operating PEFC were obtained, and the relationships between the parameters were studied. Supersaturated water inside the cell was found both experimentally and computationally. p(O(2)) and the water concentration were concluded to be the two most important factors in determining the distribution of power generation.

    DOI

  • Visualization of Oxygen Partial Pressure and Numerical Simulation of a Running Polymer Electrolyte Fuel Cell with Straight Flow Channels to Elucidate Reaction Distributions

    Katsuya Nagase, Haruki Motegi, Masakazu Yoneda, Yuzo Nagumo, Takeo Suga, Makoto Uchida, Junji Inukai, Hiroyuki Nishide, Masahiro Watanabe

    CHEMELECTROCHEM   2 ( 10 ) 1495 - 1501  2015.10  [Refereed]

     View Summary

    Visualization of the oxygen partial pressure (p(O(2))) was performed at the surface of a gas diffusion layer (GDL) and the upper part of the gas-flow channel of the cathode of an operating polymer electrolyte fuel cell (PEFC) with straight flow channels by using an oxygen-sensitive luminescent dye film. The gradient of p(O(2)) inside a channel was clearly observed, even on the GDL surface across the channel. A numerical simulation was performed to understand the reaction distributions inside the PEFC. By visualization and numerical simulation, the distributions of p(O(2)), the current density, water concentration, and temperature in the operating PEFC were obtained, and the relationships between the parameters were studied. Supersaturated water inside the cell was found both experimentally and computationally. p(O(2)) and the water concentration were concluded to be the two most important factors in determining the distribution of power generation.

    DOI

  • Ionic Liquid-Triggered Redox Molecule Placement in Block Copolymer Nanotemplates toward an Organic Resistive Memory

    Takeo Suga, Kohei Aoki, Hiroyuki Nishide

    ACS MACRO LETTERS   4 ( 9 ) 892 - 896  2015.09  [Refereed]

     View Summary

    The integration of functional components such as metal nanoparticles, metal salts, or ionic liquids with well-defined block copolymer (BCP) nanotemplates via non-covalent bond interactions has afforded hybrid functional materials. Here, we designed an ionic liquid (IL)-functionalized redox-active TEMPO (2,2,6,6-tetramethylpiperidine-N-oxy) radical (guest), investigated phase-selective incorporation/placement into host BCP nanostructured matrices, and established a rational approach to functionalize BCP templates. On-demand domain functionalization of poly(styrene-b-ethyl-ene oxide) (PS-b-PEO) was triggered by ion-ionophore interaction, as verified by the suppression of PEO melting transition in DSC, and the swelling behavior of the PEO spherical domain in AFM, TEM, and X-ray scattering characterizations. The obtained BCP layer containing the redox-active TEMPO and IL was utilized as an active layer in the diode-structured memory device, which exhibited on/off resistive switching (on/off ratio >10(3)). Systematic placement of TEMPO and IL in the BCP spherical domain allowed for tuning of the switching characteristics and revealed that the formation of a discontinuous redox-active domain was critical for rewritable resistive switching.

    DOI

  • Ionic Liquid-Triggered Redox Molecule Placement in Block Copolymer Nanotemplates toward an Organic Resistive Memory

    Takeo Suga, Kohei Aoki, Hiroyuki Nishide

    ACS MACRO LETTERS   4 ( 9 ) 892 - 896  2015.09  [Refereed]

     View Summary

    The integration of functional components such as metal nanoparticles, metal salts, or ionic liquids with well-defined block copolymer (BCP) nanotemplates via non-covalent bond interactions has afforded hybrid functional materials. Here, we designed an ionic liquid (IL)-functionalized redox-active TEMPO (2,2,6,6-tetramethylpiperidine-N-oxy) radical (guest), investigated phase-selective incorporation/placement into host BCP nanostructured matrices, and established a rational approach to functionalize BCP templates. On-demand domain functionalization of poly(styrene-b-ethyl-ene oxide) (PS-b-PEO) was triggered by ion-ionophore interaction, as verified by the suppression of PEO melting transition in DSC, and the swelling behavior of the PEO spherical domain in AFM, TEM, and X-ray scattering characterizations. The obtained BCP layer containing the redox-active TEMPO and IL was utilized as an active layer in the diode-structured memory device, which exhibited on/off resistive switching (on/off ratio >10(3)). Systematic placement of TEMPO and IL in the BCP spherical domain allowed for tuning of the switching characteristics and revealed that the formation of a discontinuous redox-active domain was critical for rewritable resistive switching.

    DOI

  • Topochemical conversion of a dense metal-organic framework from a crystalline insulator to an amorphous semiconductor

    S. Tominaka, H. Hamoudi, T. Suga, T. D. Bennett, A. B. Cairns, A. K. Cheetham

    Chemical Science   6 ( 2 ) 1465 - 1473  2015.02  [Refereed]

     View Summary

    © The Royal Society of Chemistry 2015. The topochemical conversion of a dense, insulating metal-organic framework (MOF) into a semiconducting amorphous MOF is described. Treatment of single crystals of copper(i) chloride trithiocyanurate, CuICl(ttcH3) (ttcH3 = trithiocyanuric acid), 1, in aqueous ammonia solution yields monoliths of amorphous CuI1.8(ttc)0.6(ttcH3)0.4, 3. The treatment changes the transparent orange crystals of 1 into shiny black monoliths of 3 with retention of morphology, and moreover increases the electrical conductivity from insulating to semiconducting (conductivity of 3 ranges from 4.2 × 10-11 S cm-1 at 20 °C to 7.6 × 10-9 S cm-1 at 140°C; activation energy = 0.59 eV; optical band gap = 0.6 eV). The structure and properties of the amorphous conductor are fully characterized by AC impedance spectroscopy, X-ray photoelectron spectroscopy, X-ray pair distribution function analysis, infrared spectroscopy, diffuse reflectance spectroscopy, electron spin resonance spectroscopy, elemental analysis, thermogravimetric analysis, and theoretical calculations.

    DOI

  • Real-time visualization of oxygen partial pressures in straight channels of running polymer electrolyte fuel cell with water plugging

    Katsuya Nagase, Takeo Suga, Yuzo Nagumo, Makoto Uchida, Junji Inukai, Hiroyuki Nishide, Masahiro Watanabe

    JOURNAL OF POWER SOURCES   273   873 - 877  2015.01  [Refereed]

     View Summary

    Visualization inside polymer electrolyte fuel cells (PEFCs) for elucidating the reaction distributions is expected to improve the performance, durability, and stability. An oxygen-sensitive film of a luminescent porphyrin was used to visualize the oxygen partial pressures in five straight gas-flow channels of a running PEFC with liquid-water blockages formed at the end of the channels. The blockage greatly lowered and unstabilized the cell voltage. The oxygen partial pressure decreased nearly to 0 kPa in the blocked channel. With a water blockage in a channel, the oxygen partial pressures in the adjacent channels were lowered due to an extra demand of oxygen consumption. When the number of the blocked channels increased, the oxygen partial pressure in the unblocked channels became much lowered. When the water blockages disappeared, the oxygen partial pressures quickly returned to the values before plugging. The influence of the cross flows of air through the gas diffusion layers in straight channels was much smaller than that in serpentine flow channels. (C) 2014 Elsevier B.V. All rights reserved.

    DOI

  • Phenothiazine-functionalized redox polymers for a new cathode-active material

    Ali A. Golriz, Takeo Suga, Hiroyuki Nishide, Ruediger Berger, Jochen S. Gutmann

    RSC ADVANCES   5 ( 29 ) 22947 - 22950  2015  [Refereed]

     View Summary

    Redox-active, phenothiazine-functionalized polymers were synthesized and employed as a promising cathode-active material (similar to 3.7 V vs. Li, 77 Ah kg(-1)) in a rechargeable battery. The longer spacer between phenothiazine and the polymer backbone contributed to the stability of the formed radical cations, resulting in decelerated self-discharge and improved cycle performance.

    DOI

  • Oxygen partial pressures on gas-diffusion layer surface and gas-flow channel wall in polymer electrolyte fuel cell during power generation studied by visualization technique combined with numerical simulation

    Yuta Ishigami, Wihatmoko Waskitoaji, Masakazu Yoneda, Kenji Takada, Tsuyoshi Hyakutake, Takeo Suga, Makoto Uchida, Yuzo Nagumo, Junji Inukai, Hiroyuki Nishide, Masahiro Watanabe

    JOURNAL OF POWER SOURCES   269   556 - 564  2014.12  [Refereed]

     View Summary

    Visualization of the oxygen partial pressures was carried out at the surface of a gas diffusion layer (GDL) for the first time together with the upper part of the gas-flow channel of the cathode of a running polymer electrolyte fuel cell (PEFC) using two different oxygen-sensitive luminescent dye films. The visualized distributions of the oxygen partial pressures at the GDL and the upper gas-flow channel during the PEFC operation were very different in a conventional test cell. The change in the distribution of the oxygen partial pressures was observed by changing the oxygen utilization, which should be connected with the reactive locations in the membrane-electrode assembly (MEA). A numerical calculation was carried out to understand the distributions of water and current density inside the MEA. The water distribution inside the MEA was confirmed to strongly affect the distributions of the current density and the oxygen /partial pressure. (C) 2014 Elsevier B.V. All rights reserved.

    DOI

  • Synthesis of Pendant Radical- and Ion-Containing Block Copolymers via Ring-Opening Metathesis Polymerization for Organic Resistive Memory

    Takeo Suga, Miki Sakata, Kohei Aoki, Hiroyuki Nishide

    ACS MACRO LETTERS   3 ( 8 ) 703 - 707  2014.08  [Refereed]

     View Summary

    Ring-opening metathesis polymerization (ROMP) using Grubbs third-generation catalyst directly yielded a norbornene-based polymer bearing robust redox-active radicals without any protection. Successive addition of imidazolium-containing norbomene in a one-pot reaction during ROMP produced pendant radical- and ion-containing block copolymers. The diode-structured thin-film devices fabricated with the obtained block polymers that had morphologies of spheres, lamellae, and inverse spheres exhibited conductive switching (write-once read-many-times, WORM) under a bias voltage, which revealed the dominant effect of the location of radicals and ions in the microphase-segregated domains on memory characteristics.

    DOI

  • Photoactive Polyesters Containing o-Nitro Benzyl Ester Functionality for Photodeactivatable Adhesion

    Stephen M. June, Takeo Suga, William H. Heath, Qin Lin, Rama Puligadda, Lei Yan, David Dillard, Timothy E. Long

    JOURNAL OF ADHESION   89 ( 7 ) 548 - 558  2013.07  [Refereed]

     View Summary

    The fabrication of modern microelectronic silicon devices mechanically challenges these thin silicon substrates during manufacturing operations. Melt and solution polyesterification enabled the synthesis of polyesters containing photoreactive o-nitro benzyl ester units for use as a potential photocleavable adhesive. Melt transesterification provided a solvent-free method for synthesis of 2-nitro-p-xylylene glycol (NXG)-containing polyesters of controlled molecular weights. 1H NMR spectroscopy confirmed the chemical composition of the photoactive polyesters. Size exclusion chromatography (SEC) determined the number-average molecular weights (Mn) of the polyesters synthesized in the range of 6000 to 12000g/mol. 1H NMR spectroscopy confirmed increasing levels of photocleavage of the o-nitro benzyl ester functionality with increasing exposure to broad wavelength UV irradiation, and exposure levels ranged from 0187J/cm2 UVA. Photocleaveage of approximately 90% of the o-nitro benzyl ester (ONB) units within the backbone of the polymer occurred at maximum dosage. Wedge fracture testing revealed approximately a two-fold decrease in fracture energy upon UV irradiation, suggesting that these structural adhesives offer potential for commercial flip bonding applications.

    DOI

  • Electrospinning of radical polymers: redox-active fibrous membrane formation

    Takeo Suga, Matthew T. Hunley, Timothy E. Long, Hiroyuki Nishide

    POLYMER JOURNAL   44 ( 3 ) 264 - 268  2012.03  [Refereed]

     View Summary

    Redox-active but highly durable nitroxide radicals, that is, 2,2,6,6-tetramethylpiperidinyl-4-oxy (TEMPO), enabled direct electrospinning of radical-containing polymers without additional processing aids (such as polymer blends, post-doping, or protection/deprotection) and produced redox-active fibrous membranes with high surface area. The solution rheological behavior of the TEMPO-substituted polymethacrylate was similar to the neutral conventional polymers, and electrospinning of the radical polymers yielded submicrometer-scaled fibrous membranes without any defects on the radical moiety. The obtained membrane exhibited stable redox response, leading to redox catalysts or electrode-active materials toward organic-based flexible rechargeable battery. Polymer Journal (2012) 44, 264-268; doi:10.1038/pj.2011.120; published online 7 December 2011

    DOI

  • Redox-active radical polymers for a totally organic rechargeable battery

    Takeo Suga, Hiroyuki Nishide

    ACS Symposium Series   1096   45 - 53  2012

     View Summary

    "Radical polymers" bearing a high density of unpaired electrons in a pendant, non-conjugated fashion on each repeating unit were utilized as cathode- and anode-active materials in a totally organic-based rechargeable battery. Careful molecular design of radical polymers such as nitroxide and galvinoxyl derivatives produced remarkably stable p- and n-type redox couples, which provided three different battery configurations. The power-rate performance of these cells was excellent (360 C rate, 10 sec charge/discharge), as a result of the rapid redox process of the organic radical moieties in the amorphous polymer layer. Organic polymer-based electrodes also allowed their utilization to a flexible, paper-like, and transparent rechargeable energy-storage device. © 2012 American Chemical Society.

    DOI

  • Real-Time Visualization of CO2 Generated by Corrosion of the Carbon Support in a PEFC Cathode

    Yuta Ishigami, Itsumi Maeda, Kenji Takada, Tsuyoshi Hyakutake, Takeo Suga, Junji Inukai, Makoto Uchida, Yuzo Nagumo, Hiroyuki Nishide, Masahiro Watanabe

    ELECTROCHEMICAL AND SOLID STATE LETTERS   15 ( 4 ) B51 - B53  2012  [Refereed]

     View Summary

    Start-up and shut-down cycling in PECFs causes severe degradation, because the carbon supports at the cathode catalyst layers are corroded due to the instantaneous reaction with H2O. We developed a new CO2 visualization system using a CO2-sensitive dye for detecting the generation of CO2 during the corrosion processes in real time and with spatial resolution. The corrosion occurring during the shut-down process continued longer near the inlet and produced a more serious effect than during the start-up process, near the outlet. This new CO2 visualization technique should help to minimize the corrosion of carbon supports in all types of PEFCs. (C) 2012 The Electrochemical Society. [DOI:10.1149/2.018204esl] All rights reserved.

    DOI

  • Morphology-Driven Modulation of Charge Transport in Radical/Ion-Containing, Self-Assembled Block Copolymer Platform

    Takeo Suga, Shunya Takeuchi, Hiroyuki Nishide

    ADVANCED MATERIALS   23 ( 46 ) 5545 - +  2011.12  [Refereed]

     View Summary

    A TEMPO-substituted ionic liquid was selectively incorporated into well-defined, self-assembled block copolymer templates, which served as an active layer for organic nonvolatile memory. Phase structures (sphere, cylinder, and lamellae) and their orientation modulated the resistive switching behavior, which demonstrated the unprecedented, morphology-driven charge transport in the organic electronic devices.

    DOI PubMed

  • Redox-active radical polymers for rapid charge-storage and -transport

    Takeo Suga, Hiroyuki Nishide

    ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY   241  2011.03

     View Summary

    Radical polymers bearing a high density of unpaired electrons in a pendant, non-conjugated fashion on each repeating unit provided a rapid, reversible, and quantitative redox behavior in an electrode form. Careful selection of radicals (TEMPO, galvinoxyl, and nitronylnitroxide, etc.) produced remarkably stable p- and n-type redox couples, which lead to the totally organic-based rechargeable batteries. The power-rate performance of these cells was excellent (360 C rate, 10 sec charge/discharge), as a result of the simple, rapid redox process of the organic radical moieties with no associated structural change in the amorphous polymer layer. Organic polymer-based electrodes are amenable to roll-to-roll or inkjet processing, which allowed the fabrication of a flexible, paper-like, and transparent rechargeable energy-storage device, which could be embedded in radio-frequency identification tags, smart cards and electronic paper.

  • p- and n-Type Bipolar Redox-Active Radical Polymer: Toward Totally Organic Polymer-Based Rechargeable Devices with Variable Configuration

    Takeo Suga, Shuhei Sugita, Hiroki Ohshiro, Kenichi Oyaizu, Hiroyuki Nishide

    ADVANCED MATERIALS   23 ( 6 ) 751 - +  2011.02  [Refereed]

     View Summary

    The p- and n-type bipolar redox-active radical polymer with a nitronylnitroxyl group, poly(nitronylnitroxylstyrene), expands its utilization as a cathode-or anode-active material in organic polymer-based rechargeable devices with two unprecedented configurations: a poleless battery and a "rocking-chair type" battery. These batteries exhibit a remarkably high power rate capability (chargeable within 20 s) and high cycle performance.[GRAPHICS].

    DOI PubMed

  • Synthesis and Charge Transport Properties of Redox-Active Nitroxide Polyethers with Large Site Density

    Kenichi Oyaizu, Takeshi Kawamoto, Takeo Suga, Hiroyuki Nishide

    MACROMOLECULES   43 ( 24 ) 10382 - 10389  2010.12  [Refereed]

     View Summary

    To maximize the theoretical redox capacity of polymers containing cyclic nitroxides as redox active pendant groups for high density charge storage application, a compact five membered ring with the smallest equivalent weight among the robust cyclic nitroxides was directly bound to a poly(ethylene oxide) chain 2,2,5,5 Tetramethyl 3 oxiranyl-3-pyrrolin 1 oxyl was synthesized and polymerized via anionic coordinated ring-opening polymerization utilizing diethyl zinc/H2O as an initiator The unpaired electron in the monomer survived during the polymerization giving rise to a high density redox polymer with a weight-specific theoretical capacity of 147 mA h/g Cyclic voltammetry of the polymer layer confined at the surface of an electrode revealed a large redox capacity comparable to the theoretical capacity which was ascribed to the efficient swelling and yet insoluble properties of the polyether in electrolyte solutions by virtue of the high molecular weight of >10(5) and adhesive properties allowing immobilization of the layer on the electrode surface The redox capacity also indicated that the ionophoric polyether matrix accommodated electrolyte anions through the polymer/electrolyte interface to neutralize positive charges produced by the oxidation of the neutral radicals at the polymer/electrode interface The diffusion coefficient for the redox gradient driven charge hopping process corresponded to a large second order rate constant in the order of 10(7) M-1 s(-1), which suggested an efficient electron self-exchange reaction throughout the polymer layer due to the large redox site population and hence to the small intersite distance Test cells fabricated with a polymer/carbon fiber composite layer on an aluminum current collector as the cathode and a Li anode sandwiching an electrolyte layer were capable of charging and discharging as a secondary battery with an output voltage near 3 7 V and were durable for more than 10(3) charging discharging cycles without substantial degradation

    DOI

  • Rechargeable Batteries Using Robust but Redox Active Organic Radicals

    Takeo Suga, Hiroyuki Nishide

    Stable Radicals: Fundamentals and Applied Aspects of Odd-Electron Compounds     507 - 519  2010.07

    DOI

  • Photo-Reactive Polyimides and Poly(siloxane imide)s as Reversible Polymeric Interfaces

    Stephen M. June, Takeo Suga, William H. Heath, Timothy E. Long, Qin Lin, Rama Puligadda

    JOURNAL OF ADHESION   86 ( 10 ) 1012 - 1028  2010  [Refereed]

     View Summary

    Polyimides and poly(siloxane imide)s containing photo-active cyclobutane diimide units were developed as reversible adhesives for temporary bonding in micro-fabrication processes. Poly(amic acid) formation in dipolar aprotic solvents and subsequent chemical or thermal solution imidization yielded the corresponding organic soluble polyimides. Incorporation of nonplanar (alicyclic or bicyclic) structures and poly(dimethyl siloxane) blocks into the main chain improved the solubility. The synthesized poly(siloxane imide)s afforded tough and ductile films, which exhibited a rubbery plateau in the storage modulus, as observed using dynamic mechanical analysis. This plateau was attributed to the microphase-separation of the poly(dimethyl siloxane) segments and the polyimide segments. Spin-coated thin films on silicon substrates were photo-degraded with ultraviolet-C (UVC) light (254nm). Nuclear magnetic resonance (NMR) spectroscopy demonstrated a growth in the proton resonance corresponding to the formation of maleimide functionality upon photo-cleavage. This observed photo-cleavage suggests possible applications as temporary structural adhesives.

    DOI

  • Synthesis of Poly(oxoammonium salt)s and Their Electrical Properties in the Organic Thin Film Device

    Takeo Suga, Shunya Takeuchi, Takanori Ozaki, Miki Sakata, Kenichi Oyaizu, Hiroyuki Nishide

    CHEMISTRY LETTERS   38 ( 12 ) 1160 - 1161  2009.12  [Refereed]

     View Summary

    Two redox-active poly(oxoammonium salt)s were synthesized via chemical oxidation of a TEMPO-substituted polymer, or conventional radical polymerization of the oxoammonium monomer, respectively. The diode-structured thin film device composed of poly(oxoammonium salt) with radical conc. of 6-43% exhibited a resistive switching behavior (ON-OFF ratio > 10(3)), in contrast to the radical-free poly(oxoammonium salt), which revealed that the coexistence of radical/oxoammonium salts contributed to a significant change in I-V characteristics.

    DOI

  • 有機ラジカル電池: フレキシブル全有機蓄電デバイスへ向けて

    須賀健雄, 西出宏之

    月刊 機能材料   29 ( 10 ) 36 - 42  2009.10

  • POLY 516-Photoactive poly(siloxane imides) as high performance structural adhesives with tailorable interfacial strength

    Stephen M. June, Takeo Suga, William H. Heath, Qin Lin, Rama Puligadda, Timothy E. Long

    ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY   238  2009.08

  • Photoactive poly(siloxane imides) as high performance structural adhesives with tailorable interfacial strength. June, Stephen M.; Suga, Takeo; Heath, William H.; Lin, Qin; Puligadda, Rama; Long, Timothy E.

    S. M. June, T. Suga, W. H. Heath, Q. Lin, R. Puligadda, T. E. Long

    Polymer Preprints    2009.08

  • POLY 124-2-Nitro-p-xylene glycol as a functional monomer for photoreleasable adhesion

    Stephen M. June, Takeo Suga, William H. Heath, Qin Lin, Rama Puligadda, Timothy E. Long

    ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY   238  2009.08  [Refereed]

  • Emerging N-Type Redox-Active Radical Polymer for a Totally Organic Polymer-Based Rechargeable Battery

    Takeo Suga, Hiroki Ohshiro, Shuhei Sugita, Kenichi Oyaizu, Hiroyuki Nishide

    ADVANCED MATERIALS   21 ( 16 ) 1627 - +  2009.04

     View Summary

    A n-type and redox-active radical polymer bearing galvinoxyl radicals, poly (galvinoxylstyrene), is utilized as an anode-active material, which enabled, for the first time, the fabrication of a totally organic polymer-based rechargeable battery in conjunction with p-type redox-active radical polymer. This battery was characterized by its remarkably high power rate capability.

    DOI

  • Synthesis of Diazocine-Containing Poly(arylene ether sulfone)s for Tailored Mechanical and Electrochemical Performance

    Takeo Suga, Sungsool Wi, Timothy E. Long

    MACROMOLECULES   42 ( 5 ) 1526 - 1532  2009.03

     View Summary

    A series of poly(arylene ether sulfone) copolymers containing the diazocine unit (0, 20, 50, 80, 100 mol %) were synthesized via step-growth polymerization. Copolymer compositions exhibited number-average molecular weights exceeding 30 000 g/mol, and mechanically ductile films were obtained for all compositions. The random copolymers exhibited enhanced thermal stability (T-d10% = 500-550 degrees C) and mechanical properties (tensile stress = 45-65 MPa), and the thermomechanical performance was predictable based on copolymer composition. A secondary transition in the dynamic mechanical analysis appeared at 28 degrees C, which was attributed to segmental motion of the bulky diazocine and biphenyl units. X-ray single crystallography and H-1 NMR spectroscopy as a function of temperature revealed that the diazocine ring existed in the boat-shaped conformation. The effective dipolar couplings of site-specific H-1-C-13 dipolar couplings in the aromatic rings were measured using DIPSHIFT solid state NMR spectroscopy at various temperatures. The experimental data indicated that the bulkier diazocine group experienced slower ring-flip motion than the smaller phenylene group. Cyclic voltammograms of diazocine-containing poly(arylene ether sulfone)s exhibited two reversible reduction peaks at -0.68 and -1.21 V under inert and basic conditions. UV spectra of the diazocine group in the reduced state indicated an extended pi-electron structure, which supported the boat- to planar-conformational change (molecular actuation) via redox reactions.

    DOI

  • Characterizing temporary bonding adhesives using a wedge test

    L. Yan, T. Suga, S. M. June, T. E. Long, D. A. Dillard

    12th International Conference on Fracture 2009, ICF-12   8   6347 - 6355  2009

     View Summary

    Reversible adhesion has long been of significant practical interest for a range of applications including controllable adhesion, photolithography, temporary bonding required for wound dressings and certain manufacturing processes, and disassembly for repairing and recycling. UV degradable materials find applications in medical and microelectronic fields due to their dramatic property changes after UV irradiation, allow for easy removal of the adhesive. A series of UV cleavable adhesives has been synthesized to investigate their ability to debond more readily as a function of UV radiation dosage. In this paper a wedge test, from elevated temperature exposure or photo-degradation, is used to measure the reduction in resistance to debonding. By using fracture mechanics principles and recording the growing debond length as a function of exposure, the fracture energy can be determined. Tests are conducted to measure how fracture energy decreases after varying amounts of thermal exposure or UV irradiation. The debond surfaces and locus of failure are also investigated in this study.

  • Redox-Active Nitroxide Radical Polymers: From Green Catalysts to Energy Storage Devices

    Wihatmoko Waskitoaji, Takeo Suga, Hiroyuki Nishide

    INTERNATIONAL WORKSHOP ON ADVANCED MATERIAL FOR NEW AND RENEWABLE ENERGY   1169   13 - 18  2009  [Refereed]

     View Summary

    Robust but redox-active radical polymers bearing 2,2,6,6-tetramethylpiperidin-N-oxy (TEMPO) were investigated as a metal-free, green mediator/catalyst for the oxidation of alcohol derivatives, and as a new electrode-active and charge-storage material. The TEMPO-mediated oxidation of the primary alcohol group of the natural cellulose improved the water-dispersivity of cellulose, and the polymer-supported catalysts or redox resins allow facile removal of catalysts from products by simple filtration. Other radical molecule (e.g. galvinoxyl) was also used as a mediator, which is coupled with the molecular oxygen. A reversible one-electron redox reaction of TEMPO allowed its application as an electrode-active material featuring high cyclability (> 500 cycles), relatively high battery electrode capacity (100-135 mAh/g), and fast electrode kinetics, leading to the high power rate capability of the battery. The radical polymer-based electrodes also provided good processability and shape flexibility, which promised the paper-like and wearable energy-storage devices.

    DOI

  • Synthesis and characterization of radical-bearing polyethers as an electrode-active material for organic secondary batteries

    Kenichi Oyaizu, Takeo Suga, Kentaro Yoshimura, Hiroyuki Nishide

    MACROMOLECULES   41 ( 18 ) 6646 - 6652  2008.09

     View Summary

    In search of polymer backbones to bind organic radical pendant groups as redox centers for high-density charge storage application, polyether was employed as a flexible chain with a low glass transition temperature and affinity to electrolyte solutions. Cyclic ethers bearing nitroxide radicals were synthesized and polymerized via ring-opening polymerization utilizing various initiators. Polyethers bearing robust radical substituents such as 2,2,6,6-tetramethylpiperidin-l-oxyl-4-yl and 2,2,5,5-tetramethyl-2,5-dihydro-1H-pyrrol-l-oxyl-3-yl groups with high density, i.e., per repeating unit with small equivalent weights, were prepared by the anionic polymerization of the corresponding epoxides. Cyclic voltammetry of the radical polyethers, obtained for polymer/carbon composites confined at an aluminum current collector, revealed large redox capacities comparable to the formula weight-based theoretical values, which was ascribed to the efficient swelling and yet insoluble properties of the polyethers in electrolyte solutions by virtue of their high molecular weights and adhesive properties to be held on electrode surfaces. The redox capacity also indicated that the ionophoric polyether matrix accommodated electrolyte anions to compensate positive charges produced by the oxidation of the neutral radicals at the polymer/electrode interface, allowing charge propagation deep into the polymer layer by a site-hopping mechanism. Test cells fabricated with the polymer/carbon composite as the cathode and a Li anode, sandwiching an electrolyte layer, performed as a secondary battery at output voltages near 3.6 V without substantial degradation even after 100 charging-discharging cycles.

    DOI

  • POLY 279-Synthesis of diazocine-containing polysulfones and their mechanical and electrochemical properties

    Takeo Suga, Timothy E. Long

    ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY   235  2008.04

  • POLY 159-Synthesis of photosensitive poly(arylene imide sulfone)s

    Takeo Suga, Timothy E. Long

    ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY   235 ( 1 ) 622 - 623  2008.04

  • POLY 499-Block copolymers containing stabile free radicals: Synthesis and magnetic force microscopic morphological investigations

    Takeo Suga, Brian D. Mather, Hiroyuki Nishide, Timothy E. Long

    ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY   235 ( 1 ) 304 - 305  2008.04  [Refereed]

  • Block copolymers containing stable free radicals: Synthesis and magnetic force microscopic morphological investigations

    Takeo Suga, Brian D. Mather, Hiroyuki Nishide, Timothy E. Long

    American Chemical Society, Polymer Preprints, Division of Polymer Chemistry   49 ( 1 ) 304 - 305  2008

  • Synthesis of photosensitive poly(arylene imide sulfone)s

    Takeo Suga, Timothy E. Long

    American Chemical Society, Polymer Preprints, Division of Polymer Chemistry   49 ( 1 ) 622 - 623  2008

  • Synthesis of diazocine-containing polysulfones and their mechanical and electrochemical properties

    Takeo Suga, Timothy E. Long

    American Chemical Society, Polymer Preprints, Division of Polymer Chemistry   49 ( 1 ) 388 - 389  2008

  • Cathode- and anode-active poly(nitroxylstyrene)s for rechargeable batteries: p- and n-type redox switching via substituent effects

    Takeo Suga, Yong-Jin Pu, Shinji Kasatori, Hiroyuki Nishide

    MACROMOLECULES   40 ( 9 ) 3167 - 3173  2007.05  [Refereed]

     View Summary

    Three polystyrenes bearing redox-active nitroxide radical(s) in each repeating unit, poly[4-(N-tert-butyl-N-oxylamino)styrene] (1), poly[3,5-di(N-tert-butyl-N-oxylamino)styrene] (2), and poly[4-(N-tert-butyl-N-oxylamino)-3-trifluoromethylstyrene] (3), were synthesized via free radical polymerization of protected precursor styrenic derivatives and subsequent chemical oxidation. The radicals in these polymers were robust at ambient conditions, and the polymers possessed radical densities of 2.97 x 10(21), 4.27 x 10(21), and 1.82 x 10(21) unpaired electrons/g for 1-3, respectively, resulting in an electrode-active material with a high charge/discharge capacity. Particularly, the dinitroxide functional polymer 2 possessed the highest radical density. Cyclic voltammetry of the poly(nitroxylstyrene) 1 revealed a reversible redox at 0.74 V vs Ag/AgCl, which was assigned to the oxidation of the nitroxide radical to form the oxoammonium cation (p-type doped state). On the other hand, the poly(nitroxylstyrene) ortho-substituted with the electron-withdrawing trifluoromethyl group 3 showed a reversible redox at -0.76 V, ascribed to the n-type redox pair between the nitroxide radical and the aminoxy anion. Thus, the nitroxide radical polymer could be switched from p-type material suitable for a cathode to n-type material (anode-active) via altering the electron-withdrawing character of the substituents on the poly(nitroxylstyrene). This is the first report of an n-type radical polymer and the first report of using substituent effects to switch the redox behavior of the polymer. This versatile switching ability enables these polymers to function as components of metal-free electrodes in rechargeable batteries.

    DOI

  • Photocrosslinked nitroxide polymer cathode-active materials for application in an organic-based paper battery

    Takeo Suga, Hiroaki Konishi, Hiroyuki Nishide

    CHEMICAL COMMUNICATIONS   ( 17 ) 1730 - 1732  2007  [Refereed]

     View Summary

    A nitroxide radical functional polymer was photocrosslinked for the first time without significant side reactions, producing a cathode-active thin film, leading to an organic-based paper battery.

    DOI

  • Ring-opening polymerization of nitroxide-substituted epoxide derivatives and their redox property

    Kentaro Yoshimura, Takeo Suga, Hirovuki Nishide

    Polymer Preprints, Japan   55 ( 1 ) 1391  2006

     View Summary

    A nitroxide radical is electrochemically oxidized to the oxoammonium cation(p-type doping) and reduced to the nitroxide reversively. Based on this redox property, we have reported application of the nitroxide radical polymer to an electrode-active material. Epoxide derivatives bearing 2,2,6,6- tetramethylpipelidine-A/-oxyl were synthesized and polymerized by ring-opening polymerization. In this report, the obtained polymers were characterized by IR, elemental analysis, ESR and SQUID measurement. Redox property of these radical polymers was examined by cyclic voltammetry. The cycle performance during charging and discharging of the fabricated cell displayed a plateau voltage at 3.7 V, and no significant deterioration in the capacity was observed more than 100 cycles.

  • Synthesis of polystyrene bearing galvinoxyl radical and its redox behavior

    Hiroki Ohshiro, Takeo Suga, Hiroyuki Nishide

    Polymer Preprints, Japan   55 ( 1 ) 1390  2006

     View Summary

    Galvinoxyl radical, known as a stable organic radical, was selected as a new candidate for a cathodeand/or anode-active material for a secondary battery. Styrene derivative bearing the galvinoxyl radical was synthesized via four steps, and polymerized to give the precursor polymer (Mn=10 4). Chemical oxidation yielded the corresponding radical polymer. The obtained polymer was characterized by spectroscopic measurements. Electrochemical measurements revealed its stable redox behavior. The cell performance will also be reported.

  • Synthesis of radical polymers and their application to an organic radical battery

    Takeo Suga, Kentaro Yoshimura, Hiroki Ohshiro, Hiroaki Konishi, Hiroyuki Nishide

    Polymer Preprints, Japan   55 ( 2 ) 4659 - 4660  2006

     View Summary

    Based on the redox couples of a nitroxide radical, organic radical polymers have been utilized as the electrode-active or charge-storage component for a secondary battery, so-called "organic radical battery". Organic radical battery has several advantages: high capacity, high power-rate performance, long cycle ability, and environmentally-benign features. We report here the synthesis of a series of radical polymers and their redox properties. TEMPO-substituted polyether displayed its improved compatibility with the electrolyte solution. Photo-crosslinking of TEMPO-substituted polynorbornene was investigated as a facile and useful method leading to a slim and flexible battery. Poly (galvinoxystyrene) displayed a stable n-type redox behavior at 3.2 V vs. Li/Li+, which also holds considerable potential as an anode-active material, leading to purely organic-derived batteries. The cell performance will be also reported.

  • Synthesis of diphenylnitroxide-substituted polystyrenes and their p- and n-type redox property

    Masashi Fujinaga, Takeo Suga, Hiroyuki Nishide

    Polymer Preprints, Japan   55 ( 2 ) 3981  2006

     View Summary

    Diphenylnitroxide derivatives are known to their high radical stability and stable redox properties suitable as an electrode-active material of the next generation secondary battery. A series of p, p'-disubstituted diphenylnitroxide derivatives were synthesized, and p-substituent effect on their redox properties were investigated by electrochemical measurements. Styrene derivative bearing the diphenylnitroxide radical was synthesized via 4 steps, and polymerized to give the precursor polymer (Mn =3.2 × 103). Chemical oxidation of this polymer yielded the corresponding radical polymer. Its redox behavior will be also reported.

  • Redox property of photo-crosslinked poly(TEMPO-substituted norbornene)s

    Hiroaki Konishi, Takeo Suga, Hiroyuki Nishide

    Polymer Preprints, Japan   55 ( 2 ) 3980  2006

     View Summary

    Poly(TEMPO-substituted norbornene) was synthesized by ring-opening metathesis polymerization by using Grubbs catalyst. The polymer was photo-crosslinked by bisazide or oxetane derivatives, and applied to an electrode-active material. The obtained radical thin film displayed a stable redox behavior at 3.6V vs. Li/Li+.The test cell was fabricated with the polymer cathode and lithium anode.No deterioration of the capacity was observed after 500 cycles.

  • 「有機ラジカル電池: 主鎖分子設計と電荷輸送」

    須賀 健雄, 西出 宏之

    超分子研究会アニュアルレビュー   27   12 - 13  2006

  • Nitroxide-substituted polyether as a new material for batteries

    Takeo Suga, Kentaro Yoshimura, Hiroyuki Nishide

    Macromolecular Symposia   245-246   416 - 422  2006  [Refereed]

     View Summary

    Nitroxide-substituted polyether was synthesized as a cathode-active material for a secondary battery. Anionic ring-opening polymerization of a TEMPO-bearing glycidyl ether was carried out under bulk conditions to yield the corresponding polymer with the molecular weight of >104. The obtained polymer was insoluble, but slightly swollen in the electrolyte solution (ethylene carbonate/propylene carbonate). The test cell fabricated with a carbon composite cathode of this radical polymer displayed a plateau voltage at 3.5 V vs. Li/Li+. The cell performance was maintained even with a higher amount of the radical polymer loaded in the composite electrode, which could be ascribed to the flexible and rubbery polyether backbone and its higher compatibility with the electrolyte solution. Copyright © 2006 WILEY-VCH Verlag GmbH & Co. KGaA.

    DOI

  • Organic badical battery

    Hiruyuki Hishide, Takeo Suga

    Electrochemical Society Interface   14 ( 4 ) 32 - 36  2005.12

     View Summary

    The charging and discharging mechanism of a prototype organic radical-based lithium-ion battery, where the p-type nitroxide radical polymer forms a cathode operated in conjunction with a carbon anode, are discussed. During the charging process, the p-type radical polymer in the cathode is oxidized to the oxoammonium form. During the discharging process, the nitroxide radical is regenerated by reduction of the oxoammonium. The organic radical polymer has solvent solubility and processability, which facilitates battery manufacture through a wet, printable, and rollable process.

  • Synthesis of nitroxide radical polymers and their application to an electrode-active material

    Takeo Suga, Shinji Kasatori, Kentaro Yoshimura, Hiroyuki Nishide

    Polymer Preprints, Japan   54 ( 2 ) 4567 - 4568  2005

     View Summary

    A nitroxide radical is able to be electrochemically oxidized to the corresponding oxoammonium cation (p-type doping) and reduced to the aminoxyl anion (n-type doping). These redox properties are suitable as an electrode-active material of a next generation secondary battery. We have reported an application of TEMPO-substituted polymethacrylate to an cathode material. We report here synthesis of two nitroxide-substituted polystyrene derivatives and their electrochemical properties. Cyclic voltammogramsoftheradicalpolymersshowedthep- or n-type reversible waves which are tunable by molecular designing. TEMPO-substituted polynorbomene was synthesized by ring-opening metathesis polymerization. The solubility and processability of the radical polymer was tuned by cross-linking. The electron transfer process in the polymer composite electrode was examined by CV, normal pulse voltammmetry, and impedance measurement. The cell performance was also investigated.

  • Ring-opening polymerization of proxyl-substituted epoxide derivatives and their redox property

    Kentaro Yoshimura, Takeo Suga, Hiroyuki Nishide

    Polymer Preprints, Japan   54 ( 2 ) 4111  2005

     View Summary

    Nitroxide radical electrochemically can be oxidized to oxoammonium cation(p-type doping) and reduced reversively. Based on these redox properties, we have reported the application of nitroxide radical to an electrode-active material. In this report, we synthesized polyethyleneoxide derivatives bearing 2,2,5,5-tetramethylpirrolidine-N-oxyl(proxyl radical) and studied their redox properties. 2,2,5-trimethyl-5-oxiranylmethylpyrrolidin-1-yloxy was synthesized from 2-nitropropane via four step reactions. The obtained proxyl-substituted epoxide was polymerized by ring-opening polymerization. Poly(proxyl radical)s were identified by IR, ESR, SQUID measurement, and elemental analysis. Redox properties of these polyradicals were examined by cyclic voltammetry. The formal potential was 0.75V.

  • Polymerization of acetylenes bearing proxyl radical and their redox property

    Shinji Kasatori, Takeo Suga, Hiroyuki Nishide

    Polymer Preprints, Japan   54 ( 1 ) 1695  2005

     View Summary

    A nitroxide radical is stable at ambient conditions and has two redox couples; nitroxide radical is oxidized to oxoammonium cation (p-type doping) and reduced to aminoxyl anion (n-type doping). Based on these electrochemical properties, the nitroxide radical is expected as an electrode active material of secondary battery. In this report, we synthesized new polyacetylene derivatives bearing 2,2,5,5-tetramethylpyrrolidine-N-oxyl(proxyl radical) and studied their electrochemical properties. Two monomers were synthesized by Grignard reaction (from nitrone). The obtained acetylene monomer was polymerized by coordination polymerization and oxidized to its radical derivative. Poly(proxyl radical)s were identified by IR, ESR, SQUID measurement, and elemental analysis. Redox property of these poly(proxyl radical)s was examined by cyclic voltammetry.

  • Synthesis of nitroxide-substituted polystyrene and its n-type redox property

    Shinji Kasatori, Takeo Suga, Hiroyuki Nishide

    Polymer Preprints, Japan   54 ( 2 ) 4109  2005

     View Summary

    The nitroxide radical is expected as an electrode active material of secondary battery. We synthesized polystyrene derivatives bearing nitroxide radical and investigated their electrochemical properties. Styrene monomer was synthesized from 5-bromo-2-aminobenzotrifluoride via four step reactions. The obtained styrene monomer was polymerized by radical polymerization and oxidized to its radical derivative. Electrochemical property of the radical polymer was examined by cyclic voltammetry. The formal potential was -0.76 V.

  • Organic radical battery: Nitroxide polymers as a cathode-active material

    Hiroyuki Nishide, Shigeyuki Iwasa, Yong Jin Pu, Takeo Suga, Kentaro Nakahara, Masaharu Satoh

    Electrochimica Acta   50 ( 2-3 SPEC. ISS. ) 827 - 831  2004.11  [Refereed]

     View Summary

    Purely organic-derived nitroxide radicals, including their polymer derivative, poly(2,2,6,6-tetramethylpiperidinyloxy methacrylate) (PTMA), were characterized as a new class of cathode-active materials for lithium batteries. PTMA was stable at ambient conditions, had a tunable solubility and processability, and could undergo thermal runaway without any odor and ash. The nitroxide radicals displayed a reversible and very rapid redox to form their oxoammonium salts, which enabled a high power-rate performance during the charge and discharge process of the battery. © 2004 Elsevier Ltd. All rights reserved.

    DOI

  • Electron-transfer kinetics of nitroxide radicals as an electrode-active material

    Takeo Suga, Yong Jin Pu, Kenichi Oyaizu, Hiroyuki Nishide

    Bulletin of the Chemical Society of Japan   77 ( 12 ) 2203 - 2204  2004  [Refereed]

     View Summary

    The electron-transfer rate constants of nitroxide derivatives, 4-(N-t-butyl-N-oxylamino)-t-butylbenzene, 4-(N-t-butyl-N-oxylamino) methoxybenzene, and 2,2,6,6-tetramethylpiperidinyl-N-oxyl, were investigated by electrochemical methods, which demonstrated that these radicals can potentially be used as a high power-rate electrode-active material due to their fast electron-transfer process.

    DOI

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Books and Other Publications

  • UV硬化樹脂の開発動向と応用展開

    須賀健雄( Part: Contributor, 第3章3節 精密UV硬化技術の開発動向と応用展開)

    サイエンス&テクノロジー  2021.06 ISBN: 9784864282635

  • 撥水・撥油・親水性材料の開発動向

    穂積, 篤( Part: Contributor, 第3章8節 水中CO2捕捉に基づく親水性スマートコーティングへの展開 pp189-195)

    シーエムシー出版  2021.03 ISBN: 9784781315966

  • The latest development trends in UV/EB curing technology

    ( Part: Contributor)

    2021.03 ISBN: 9784781315959

  • Superhydrophilic, Self-cleaning Coatings Based on Zwitterion Polymers

    ( Part: Contributor, pp.601-607)

    2019.06 ISBN: 9784861047510

  • リビングラジカル重合を用いたUV硬化と傾斜ナノ構造の形成, リビングラジカル重合 - 機能性高分子の合成と応用展開, pp311-317

    須賀健雄

    シーエムシー出版  2018.08 ISBN: 9784781313368

  • "両性イオンポリマーの表面偏析に基づく機械強度に優れた超親水コーティング剤の開発", 超親水・親油性表面の技術,pp58-66

    須賀健雄

    サイエンス&テクノロジー  2018.03 ISBN: 9784864281713

  • "気相重合による元素ブロック共役高分子のその場形成と電子・光物性", 元素ブロック高分子 – 有機-無機ハイブリッド材料の新概念, pp132-138

    須賀健雄

    シーエムシー出版  2015.12 ISBN: 9784781311364

  • "PEDOTの気相重合", PEDOTの材料物性とデバイス応用, pp58-64.

    須賀健雄, 西出宏之

    シーエムシー出版  2011.12 ISBN: 9784781304786

  • “ラジカルポリマー電池”, 全固体電池開発の最前線, pp144-152.

    須賀健雄, 西出宏之

    John Wiley and Sons, Inc  2011 ISBN: 0471440264

  • "Rechargeable Batteries Using Robust But Redox-Active Organic Radicals" in Stable Radicals: Fundamental and Applied Aspects of Odd-electron Compounds

    T. Suga, H. Nishide

    NTS  2006.02 ISBN: 9784860431020

  • ”有機ラジカル電池 -基礎と応用-”, 電池革新が拓く次世代電源

    須賀健雄, 西出宏之

  • "ラジカルポリマー電池”, 高分子ナノテクノロジーハンドブック, pp881-885.

    須賀健雄, 西出宏之

    エヌ・ティー・エス  2014.03 ISBN: 9784860434106

  • ”Magnetic polymer" in Encyclopedia of Polymer Science and Technology

    H. Nishide, T. Suga

    Wiley VCH  2010.07 ISBN: 9780470770832

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Misc

  • Innovation needs scientists' network like polymers

    Takeo Suga

    Kobunshi   62 ( 3 ) 141  2013.03

    Book review, literature introduction, etc.  

     View Summary

    This essay includes some of my research topics on functional polymers, and episodes of my research life. I appreciate my former and current colleagues and advisors, who helped me to link to this academic world. And I believe to link scientists like polymer synthesis will lead to innovation in the future. Copyright ©2013 The Society of Polymer Science, Japan.

  • Redox-active radical polymer/vapor-phase polymerized polythiophene composite electrodes for a totally organic rechargeable battery

    Takeo Suga, Bjorn Winther-Jensen, Hiroyuki Nishide

    ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY   242  2011.08

    Research paper, summary (international conference)  

  • Redox-active radical polymers for organic-based energy-storage devices

    Hiroyuki Nishide, Takeo Suga

    ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY   242  2011.08

    Research paper, summary (international conference)  

     View Summary

    Emerging technologies with plastic-based flexible electronic devices have evoked keen interest in exploring next-generation flexible and printable power sources. We focused on durable, but highly redox-active property of organic radical molecules, and have developed a new class of redox polymers for electrode-active, charge-storage materials in a rechargeable battery. Radical polymers bearing a high density of unpaired electrons in a pendant, non-conjugated fashion on each repeating unit provided a rapid, reversible, and quantitative redox behavior in an electrode form. Careful selection of radicals (TEMPO, galvinoxyl, and nitronylnitroxide, etc.) produced remarkably reversible p- and n-type redox couples, which lead to the totally organic-based rechargeable batteries. The power-rate performance of these cells was excellent (a few seconds full charging/discharging), and organic polymer-based electrodes also allowed the fabrication of a flexible, paper-like, and transparent rechargeable energy-storage device. Microphase-separated radical-containing block copolymers and electrospun radical fibers toward new electronics applications will be also discussed.

  • Radical battery: A paper-like polymer-based rechargeable device

    Hiroyuki Nishide, Takeo Suga, Kenichi Oyaizu

    ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY   234  2007.08

    Research paper, summary (international conference)  

     View Summary

    Pendant radical polymers were used as electroactive charge-storage materials for secondary batteries. The radical polymers were designed to be slightly swelled but not to be dissolved in electrolyte solutions. Stable organic radicals such as nitroxides and galvinoxyl were employed as the redox centers, which were characterized by a rapid electron transfer process with current collectors and an efficient charge propagation (i.e. site-hopping) process within the polymer layer. The organic-based approach leads to the fabrication of transparent, light and flexible thin-film rechargeable devices, with rapid charging and high power rate characteristics.

Industrial Property Rights

  • 1液硬化型エポキシ樹脂組成物

    西出 宏之, 須賀 健雄, 小石 怜史

    Patent

  • Imide-Crosslinked Resin, Transparent Protective Films

    特許6707741

    Patent

  • 重合体、硬化性組成物、硬化膜及び重合体の製造方法

    佐藤嘉秀, 岩崎知一, 須賀健雄, 西出宏之

    Patent

  • 多官能化合物及びその製造方法、アミック酸化合物及びその製造方法、並びにイミド化合物の製造方法

    須賀 健雄, 西出 宏之, 小松伸一

    Patent

  • 重合体、樹脂組成物、防汚塗料組成物、重合体の製造方法、塗膜の表面にカルバメートを安定化する構造を生成する方法、塗膜の表面にカルバメートを安定化する構造を再生する

    須賀健雄, 西出宏之, 勝間田匠, 谷口佳奈, 中村淳一, 岩崎知一

    Patent

  • 硬化性組成物及び膜

    須賀 健雄, 西出 宏之

    Patent

  • 重合体、樹脂組成物、防汚塗料組成物、重合体の製造方法、塗膜の表面に両性イオン構造を生成する方法、塗膜の表面に両性イオン構造を再生する方法

    須賀健雄, 西出宏之, 勝間田匠, 谷口佳奈, 中村淳一, 岩崎知一

    Patent

  • Coatings and Fabrication of Hydrophilic Coatings

    Patent

  • Curable materials and coatings

    Patent

  • 有機太陽電池

    西出 宏之, 須賀 健雄, 伊藤 正泰

    Patent

  • ポリラジカル化合物、電極活物質および電池

    5176130

    西出 宏之, 須賀 健雄

    Patent

  • ポリラジカル化合物および電池

    5176129

    西出 宏之, 須賀 健雄

    Patent

  • 二次電池用活物質層及びその形成方法並びに二次電池用活物質層形成用塗布液

    西出 宏之, 須賀 健雄

    Patent

  • ノルボルネン系架橋共重合体及びその製造方法

    4617437

    西出 宏之, 須賀 健雄

    Patent

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Awards

  • 高分子学会広報委員会パブリシティ賞

    2017.05  

  • Lecture Award” in 1st Young Scientists’ Symposium on New Polymeric Materials Based on Element-Blocks

    2013.10  

  • Award for Encouragement of Research in Polymer Science

    2013.05  

  • IUPAC Macro2012 Lecture Award from ACS, PMSE

    2012.06  

  • FAPS 1st Polymer Congress, Young Scientists Poster Award

    2009.10  

  • Gordon Research Seminar (Polymers), One of Top 2 Oral Presentations

    2009.06  

  • JSPS Travel Award for International Symposium

    2009.06  

  • Mizuno Award (Waseda Univ.)

    2007.03  

  • 3rd IUPAC MAM-06 Poster Prize

    2006.06  

  • WISE Fellowship (Waseda Univ.)

    2004.04  

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Research Projects

  • Development of Perovskite BIPV Modules for Integration to Building Windows

    NEDO 

    Project Year :

    2020.07
    -
    2023.03
     

  • Adaptive Material Design for Superhydrophilic Polymer Coatings Based on CO2 Capture

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)

    Project Year :

    2018.04
    -
    2021.03
     

  • CO2自発固定に基づく環境「適応」型・超親水スマートコーティングの創出

    科学研究費補助金

    Project Year :

    2018.04
    -
    2021.03
     

  • 水中CO2自発固定に基づくポリマーコーティングの超親水化技術の開発

    JST  地域産学バリュープログラム

    Project Year :

    2017.10
    -
    2018.09
     

  • ナノ反応場における気相重合と元素ブロック共役高分子の構造・機能制御

    日本学術振興会  科学研究費助成事業 新学術領域研究(研究領域提案型)

    Project Year :

    2015.04
    -
    2017.03
     

    須賀 健雄

     View Summary

    共役高分子を簡便かつ各種基材にその場(in-situ)形成できる「気相酸化重合」に着目し、特にヨウ素などの気相酸化剤を用いることで各種元素ブロック(Si, Seなど)含有π共役モノマーへと対象を広げ、低バンドギャップ・移動度高い高分子半導体の新しい形成法として提示してきた。本年度は、昨年度合成に成功した剛直多分岐構造を持つアモルファス性の共役高分子を逆型ペロブスカイト型太陽電池の電荷輸送層として検討した。また、ブロック共重合体のミクロ相分離ドメインやMOFをテンプレートとしたナノ反応場での気相重合も検討した。
    1.多分岐連結した元素ブロック共役高分子の逆型ペロブスカイト太陽電池への適用
    昨年度報告したトリス(ターチエニル)ベンゼンに加え、コア部位をトリフェニルアミンとしてチエニルまたはEDOTを三置換したモノマーをそれぞれ合成、気相重合した。チタニアフリーの逆型ペロブスカイト太陽電池のホール輸送層としての適用では、変換効率は7-8%に留まったものの歩留まりは向上し、従来の直鎖型に比べ欠陥なくアモルファスな層が形成できたためと考えられる。またEDOTを連結部位とすることで、上層のペロブスカイト層との界面濡れ性も改善した。
    2. ナノ反応場での元素ブロック共役高分子のその場形成
    汎用ブロック共重合体(例えばPS-PEO)のミクロ相分離を鋳型として、芳香族相互作用によりポリスチレン相へ共役モノマーを選択的に自己集積後、ヨウ素で重合・脱ドープし共役高分子ドメインをその場構築した。ナノ反応場での重合では、ドメイン内のヨウ素(気体)の拡散性なども鍵となる。また、京大・植村准教授との班内共同研究で、多孔性金属錯体(MOF)の一次元細孔中でもロッド状無置換ポリチオフェン(軸長~10μm)の形成に成功し、異方導電性はじめ高次構造-電子物性の相関をconductive AFMなどにより評価した。

  • Functional Photo-cured Polymer Coatings via Photo-driven Controlled Radical Polymerization

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Challenging Exploratory Research

    Project Year :

    2014.04
    -
    2016.03
     

    Suga Takeo

     View Summary

    Photo-induced controlled radical polymerization has attracted recent attention for on-demand on/off control of polymerization. Organo-catalyzed iodine-transfer controlled radical polymerization is a promising approach to obtain colorless polymers with low polydispersity. The polymeric dormant containing stable C-I endgroup was prepared and utilized for chain extension/crosslinking reaction under UV irradiation. Polymerization-induced microphase-separation from miscible mixture of polymeric dormant and mono- and bi-functional acrylate monomers yielded bicontinuous morphology. Cross-sectional AFM and TEM tomography revealed evolution of unique gradient nanostructure in thickness via controlled photo-curing. The obtained nanostructured coatings are promising materials for optical coatings or porous separators.

  • In-situ Formation of Radical/p-Conjugated Polymer Blends for Rapid Charge-Storage

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Challenging Exploratory Research

    Project Year :

    2013.04
    -
    2015.03
     

    NISHIDE Hiroyuki, SUGA Takeo

     View Summary

    We proposed the combination of "charge-storage" based on redox reaction of durable organic radicals (SOMO) and "charge-conduction" through π-conjugation (HOMO-LUMO) to yield new energy-storage materials. Especially, we focused on vapor-phase oxidative polymerization (VPP) as a facile method for in-situ preparation of π-conjugated polymers. Prior to VPP process, chemical oxidants such as Fe(OTs)3 were mixed with nitroxide radical polymers to convert the corresponding oxoammonium salts, to suppress the radical inhibition of oxidative polymerization of EDOT. The obtained p- and n-type radical polymers/PEDOT blend was utilized as cathode- and anode-active materials, respectively, leading to the metal-free, wearable rechargeable battery. In-situ VPP method using oxidant vapors such as iodine also produced organic donor layer toward organic solar cells.

  • 気相重合による元素ブロック共役高分子のドメイン形成と機能展開

    日本学術振興会  科学研究費助成事業 新学術領域研究(研究領域提案型)

    Project Year :

    2013.04
    -
    2015.03
     

    須賀 健雄

     View Summary

    本課題では、予め化学酸化剤(例えばFe(OTs)3)を塗布し、共役モノマー(例えばEDOTなど)の蒸気を供給することで、導電性高いπ共役高分子を簡便に形成できる「気相酸化重合法」を起点に、従来とは逆の着想で「共役モノマーを予め塗布、揮発性の酸化剤を気相供給する」ことで、従来揮発性や熱安定性に制限されていた多様な共役モノマーの高分子化法として提示することを目的としている。特に各種元素(Se, Bなど)含有共役モノマーへと対象を拡張し、気相重合を「無置換・元素ブロック共役高分子」のその場形成法として展開した。
    (1) 元素ブロック共役高分子の電子・光物性
    昨年度までに気相重合で得たビセレノフェンやBODIPYなどの元素ブロック含有共役高分子を対象に、高分子ドナーとしての電子・光物性を検討した。ベンゾチアジアゾールなど電子求引性のコア部位導入やSe, Teなど重原子効果で長波長域の吸収を向上し、バンドギャップの調節を明らかにした。また、単層素子およびくし形電極を用いてホール移動度の異方性についても2桁程度あることを明らかにした。PCBMをアクセプターとして組み合わせた有機薄膜太陽電池では光電変換効率1%に留まり、界面制御が今後の課題として挙げられる。
    (2) 電解重合との比較
    気相重合及び電解重合で得られたポリチオフェンを例に、UV, AFMにより比較したところ、気相重合では100-200nmの粒状のポリチオフェンが緻密に形成され、より高い移動度を示すことを明らかにした。現在MOFを鋳型とする気相重合ポリチオフェンの異方導電性についても班内連携(A02班 京大植村グループ)と進めている。

  • Mitsubishi Chemical: Surface Design of Functional Polymers

    Project Year :

    2015
    -
     
     

  • Radical/Ion-Containing Block Copolymers: Self-Assembly and Application toward Organic Devices

    Project Year :

    2011.04
    -
    2014.03
     

     View Summary

    A well-defined mesostructure of block copolymer templates was successfully functionalized with redox-active radicals and charge-compensating ionic groups via ionic liquid-assisted self-assembly. The obtained PS-b-PEO layer containing TEMPO-IL 1 exhibited morphology-driven modulation of charge-transport (on/off switching) in an organic thin film device. Location of radical and ionic molecules was correlated with resistive memory characteristics (rewritable/WORM, etc). We applied Kelvin Probe Force Microscopy (KPFM) technique and conductive AFM to visualize local surface potential and local conductivity change of microdomains under the programmed bias. Radical- and ion-functionalized block copolymers were also synthesized via controlled radical polymerization and ring-opening metathesis polymerization, and utilized as the active layer for organic memory

  • 気相重合による元素ブロック共役高分子のドメイン形成と機能展開

    科学研究費助成事業(早稲田大学)  科学研究費助成事業(新学術領域研究(研究領域提案型))

    Project Year :

    2013
    -
    2014
     

     View Summary

    配向性高い共役高分子をその場(in-situ)形成できる「気相酸化重合」に着目し、各種元素(Si, Seなど)を含む低バンドギャップ・移動度高い高分子半導体の新しい形成法としての確立を目的とする。本年度は、従来とは逆の着想で「共役モノマーを予め塗布、揮発性の酸化剤を気相供給する」ことで揮発性や熱安定性に制限されていた多様な共役モノマー、特に各種元素(Se, Siなど)含有共役モノマーへ対象を拡げ、気相重合を適用するとともに、ドナー/アクセプター混合型光電変換層に向けた配向性高い高分子半導体の新しい形成法として提示した。
    (1) 気相酸化剤を用いたオリゴチオフェンの気相酸化重合
    ターチオフェン溶液を基板上に予め成膜後、化学酸化剤としてNOPF6またはI2蒸気雰囲気下で気相重合した。エタノールによる洗浄、ヒドラジンによる脱ドープを経て、無置換ポリチオフェンを各種有機溶媒に不溶な赤色薄膜として得た。I2を酸化剤とした場合、UV-vis-NIRスペクトルでは長波長側に光吸収の肩ピークが現れ、共役長の伸長および高い秩序性が示唆された。XPSスペクトルでは、I由来のピークがエタノール洗浄により消失し、NOPF6より酸化剤の除去が容易であった。
    (2) 元素ブロック共役モノマーの拡張と気相重合
    元素ブロック含有モノマーとして、セレノフェンおよびBODIPY誘導体を選択した。セレノフェンは酸化電位が高いため、ビセレノフェンへと誘導し、BODIPY誘導体では末端にチオフェンを導入して気相酸化重合に供した。気相重合により得られた共役高分子のMALDI-TOF MSより、分子量3000, 重合度10-20のピークを検出し、各モノマーの繰り返しと一致したことから、副反応なく重合体を与えることを明らかにした。また、気相重合により得られた薄膜は溶液重合よりも1桁高いホール移動度を示した。

  • Mizuho Foundation: "Functional Block Copolymers: Synthesis and their Domain/Interface Design toward Enhanced Opto-/Electronic Properties"

    Project Year :

    2013
    -
    2014
     

  • Mitsubishi Chemical: Surface Design of Functional Polymers

    Project Year :

    2013
    -
     
     

  • Radical/Ion-Containing Block Copolymers: Self-Assembly and Application toward Organic Devices

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)

    Project Year :

    2011
    -
    2013
     

    SUGA Takeo

     View Summary

    A well-defined mesostructure of block copolymer templates was successfully functionalized with redox-active radicals and charge-compensating ionic groups via ionic liquid-assisted self-assembly. The obtained PS-b-PEO layer containing TEMPO-IL 1 exhibited morphology-driven modulation of charge-transport (on/off switching) in an organic thin film device. Location of radical and ionic molecules was correlated with resistive memory characteristics (rewritable/WORM, etc). We applied Kelvin Probe Force Microscopy (KPFM) technique and conductive AFM to visualize local surface potential and local conductivity change of microdomains under the programmed bias. Radical- and ion-functionalized block copolymers were also synthesized via controlled radical polymerization and ring-opening metathesis polymerization, and utilized as the active layer for organic memory.

  • TEPCO Memorial Foundation: Electrochemical Studies of Radical Polymer Electrodes for Charge-Storage Materials

    Project Year :

    2011
    -
    2012
     

  • NEDO Project: In-situ Optical Sensor for Fuel Cells (Collaboration with Univ. of Yamanashi)

    Project Year :

    2009
    -
    2011
     

  • SOMO Design of Radical Polymers for Development of Fully Organic Rechargeable Batteries

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (S)

    Project Year :

    2007
    -
    2011
     

    NISHIDE Hiroyuki, OYAIZU Kenichi, SUGA Takeo

     View Summary

    We have been developing "organic radical batteries" by fabricating the prototypes using organic radical polymers as electode-active materials. The radical batteries are characterized by the unprecedented battery performances that accomplish both a high energy density and an excellent power rate capability, taking advantage of the designable polymer chain and the fast electron transpfer kinetics found for the radical pendants. The present research aims at establishing novel organic electrodes by unraveling the the electron-and mass-transfer processes of the radical polymers, in pursuit of basic principles that dominate the organic redox reactions through singly occupied molecular orbitals(SOMO). Rational molecular design and synthesis of radical polymers have been attempted with a view to further improve the energy and power densities to provide next-generation and sustainable organic rechargeable batteirs.

  • SOMO Design of Radical Polymers for Development of Fully Organic Rechargeable Batteries

    Project Year :

    2007
    -
    2011
     

     View Summary

    We have been developing "organic radical batteries" by fabricating the prototypes using organic radical polymers as electode-active materials. The radical batteries are characterized by the unprecedented battery performances that accomplish both a high energy density and an excellent power rate capability, taking advantage of the designable polymer chain and the fast electron transpfer kinetics found for the radical pendants. The present research aims at establishing novel organic electrodes by unraveling the the electron-and mass-transfer processes of the radical polymers, in pursuit of basic principles that dominate the organic redox reactions through singly occupied molecular orbitals(SOMO). Rational molecular design and synthesis of radical polymers have been attempted with a view to further improve the energy and power densities to provide next-generation and sustainable organic rechargeable batteirs.

  • Radical-Containing Block Copolymers: Microphase Separation and Charge Storage/Transport Modulation in the Organic Thin Film Devices

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Young Scientists (B)

    Project Year :

    2009
    -
    2010
     

    SUGA Takeo

     View Summary

    Redox-active radicals and ion pairs for charge compensation were incorporated into the microphase-separated domains, to modulate charge-injection/-transport properties, especially for a new design of organic nonvolatile memory. Radical/ion-containing block copolymers were prepared via stepwise controlled radical polymerization, or selective incorporation of TEMPO-ionic liquids into block copolymers, which construct the well-defined radical- and ionic-domains, and their interface. The correlation between the morphology and memory characteristics was investigated.

  • Radical-Containing Block Copolymers: Microphase Separation and Charge Storage/Transport Modulation in the Organic Thin Film Devices

    Project Year :

    2009
    -
    2010
     

     View Summary

    Redox-active radicals and ion pairs for charge compensation were incorporated into the microphase-separated domains, to modulate charge-injection/-transport properties, especially for a new design of organic nonvolatile memory. Radical/ion-containing block copolymers were prepared via stepwise controlled radical polymerization, or selective incorporation of TEMPO-ionic liquids into block copolymers, which construct the well-defined radical- and ionic-domains, and their interface. The correlation between the morphology and memory characteristics was investigated

  • Radical-Containing Block Copolymers: Microphase Separation and Charge Storage/Transport Modulation in the Organic Thin Film Devices

    Project Year :

    2009
    -
    2010
     

     View Summary

    Redox-active radicals and ion pairs for charge compensation were incorporated into the microphase-separated domains, to modulate charge-injection/-transport properties, especially for a new design of organic nonvolatile memory. Radical/ion-containing block copolymers were prepared via stepwise controlled radical polymerization, or selective incorporation of TEMPO-ionic liquids into block copolymers, which construct the well-defined radical- and ionic-domains, and their interface. The correlation between the morphology and memory characteristics was investigated.

  • NEDO Project: Radical Battery for Ubiquitous Power (Collaboration with NEC, DIC, and Sumitomo Seika)

    Project Year :

    2006
    -
    2007
     

  • Synthesis of Radical Polymers and their Application as an Organic Radical Battery

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)

    Project Year :

    2005
    -
    2006
     

    NISHIDE Hiroyuki, SUGA Takeo

     View Summary

    (1) Main chain structure and its redox-activity A polyether derivative bearing the redox-active 2,2,6,6-tetramethylpiperidinyl-N-oxy (TEMPO) moiety was insoluble, but slightly swollen in the electrolyte solution. The glass transition temperature (T_g) was below room temperature, and more flexible than the polymethacrylate derivatives. The cell performance fabricated with this polymer was maintained even with a higher radical polymer loading in the composite electrode, which revealed the flexible polyether backbone could contribute to its higher compatibility with the electrolyte solution and the current collector, and could also serve as a matrix for rapid electron transfer.
    Photocrosslinking was chosen as a method for providing tunable solubility of the radical polymer, increasing mechanical toughness of the film, improving design flexibility and enabling patterning of the device. A photocrosslinked TEMPO-substituted polynorbomene was obtained using a bis(azide) crosslinker, which was carefully designed to eliminate side reactions on the nitroxide moiety. The obtained radical thin film exhibited a rapid and reversible redox at 3.58 V vs. Li/Li^+ and served as a cathode-active material even without any current collector. This approach facilitated battery manufacture via a wet, printable, and rollable process, leading to an organic-based, flexible paper battery.
    (2) Electron transfer process of the radical polymer film and fabrication of the composite electrode A radical film obtained by photocrosslinking of the poly(TEMPO-substituted norbomene) displayed the redox behavior with a narrow peak-to-peak separation, resulting from the surface-confined redox species, which supported the rapid and quantitative electron transfer within 250 nm thickness. A SEM image of the radical polymer/carbon composite electrode also showed the carbon nanofiber was fully covered with the polymer (ca. 100 nm thickness) and suggested the electron can be transferred by the electron-hopping mechanism within the polymer layer.
    (3) N-type radical polymers and their application as a totally organic-derived secondary battery Cyclic voltammetry, in-situ electrolytic ESR and UV/vis spectroscopy revealed that the reversible p-type redox of poly[4-(N-t-butyl-N-oxylamino)styrene], attributed to the oxoammonium cation formation and n-type redox of poly(nitroxylstyrene) o-substituted with trifluoromethyl group corresponding to the aminoxy anion formation, was tuned by the electronic effects of substituent groups. P-and n-type redox switching with chemical modification also promises a potential application of these polymers as cathode-and anode-active materials in all-organic batteries. Poly(galvinoxylstyrene) exhibited a reversible redox at 3.15 V vs. Li/Li+ under basic conditions, attributed to the n-type redox reaction between the galvinoxyl radical and galvinoxylate anion. A test cell fabricated with this polymer anode and poly(TEMPO-substituted norbornene) cathode, displayed stable charge-discharge curves at a plateau voltage of 0.66 V, which agreed well with the difference of the formal redox potentials for both radical polymers.
    Through this study, the redox activity of the radical polymers has been correlated with their chemical structures and an all-organic-based battery was constructed, for the first time, with both radical polymers.

  • Synthesis of Radical Polymers and their Application as an Organic Radical Battery

    Project Year :

    2005
    -
    2006
     

     View Summary

    (1) Main chain structure and its redox-activity A polyether derivative bearing the redox-active 2,2,6,6-tetramethylpiperidinyl-N-oxy (TEMPO) moiety was insoluble, but slightly swollen in the electrolyte solution. The glass transition temperature (T_g) was below room temperature, and more flexible than the polymethacrylate derivatives. The cell performance fabricated with this polymer was maintained even with a higher radical polymer loading in the composite electrode, which revealed the flexible polyether backbone could contribute to its higher compatibility with the electrolyte solution and the current collector, and could also serve as a matrix for rapid electron transfer.
    Photocrosslinking was chosen as a method for providing tunable solubility of the radical polymer, increasing mechanical toughness of the film, improving design flexibility and enabling patterning of the device. A photocrosslinked TEMPO-substituted polynorbomene was obtained using a bis(azide) crosslinker, which was carefully designed to eliminate side reactions on the nitroxide moiety. The obtained radical thin film exhibited a rapid and reversible redox at 3.58 V vs. Li/Li^+ and served as a cathode-active material even without any current collector. This approach facilitated battery manufacture via a wet, printable, and rollable process, leading to an organic-based, flexible paper battery.
    (2) Electron transfer process of the radical polymer film and fabrication of the composite electrode A radical film obtained by photocrosslinking of the poly(TEMPO-substituted norbomene) displayed the redox behavior with a narrow peak-to-peak separation, resulting from the surface-confined redox species, which supported the rapid and quantitative electron transfer within 250 nm thickness. A SEM image of the radical polymer/carbon composite electrode also showed the carbon nanofiber was fully covered with the polymer (ca. 100 nm thickness) and suggested the electron can be transferred by the electron-hopping mechanism within the polymer layer.
    (3) N-type radical polymers and their application as a totally organic-derived secondary battery Cyclic voltammetry, in-situ electrolytic ESR and UV/vis spectroscopy revealed that the reversible p-type redox of poly[4-(N-t-butyl-N-oxylamino)styrene], attributed to the oxoammonium cation formation and n-type redox of poly(nitroxylstyrene) o-substituted with trifluoromethyl group corresponding to the aminoxy anion formation, was tuned by the electronic effects of substituent groups. P-and n-type redox switching with chemical modification also promises a potential application of these polymers as cathode-and anode-active materials in all-organic batteries. Poly(galvinoxylstyrene) exhibited a reversible redox at 3.15 V vs. Li/Li+ under basic conditions, attributed to the n-type redox reaction between the galvinoxyl radical and galvinoxylate anion. A test cell fabricated with this polymer anode and poly(TEMPO-substituted norbornene) cathode, displayed stable charge-discharge curves at a plateau voltage of 0.66 V, which agreed well with the difference of the formal redox potentials for both radical polymers.
    Through this study, the redox activity of the radical polymers has been correlated with their chemical structures and an all-organic-based battery was constructed, for the first time, with both radical polymers.

  • Organic Radical Polymer Battery (Collaboration with Toyo Gosei)

    Project Year :

    2005
    -
    2006
     

▼display all

Presentations

  • Wettability Switching of Diamine Polymer Coatings by CO2 Capture 招待有

    Takeo Suga, Yusuke Sahashi, Hiroyuki Nishide  [Invited]

    First International Conference on 4D Materials and Systems (4DMS)  (Yonezawa)  Electrochemical Society (ECS)

    Presentation date: 2808

  • Crosslinking of Cyclic Olefin Polymer via Thermal Imidization for Transparent Film Formation

    Takeo Suga

    Polycondensation 2018  (Alexandria)  ACS Polymer Division

    Presentation date: 2018.10

  • Telechelic Polymeric Dormant: Precise Synthesis via Iodine-Transfer Controlled Radical Polymerization

    Takeo Suga, Hiroyo Sumida, Kaname Takata, Hiroyuki Nishide

    67th Symposium on Macromolecules  (Sapporo)  The Society of Polymer Science, Japan (SPSJ)

    Presentation date: 2018.09

  • Controlled Photo-curing: Temporal/Spatial Control of Nanostructure Formation

    Takeo Suga

    8th Jilin-Korea-Waseda Alliance Annual Symposium  (Waseda) 

    Presentation date: 2018.08

  • Adaptive Material Design for Smart Marine Coatings 招待有

    Takeo Suga  [Invited]

    The 8th International Symposium of Polymer Chemistry (PC2018)  (Changchun)  CIAC

    Presentation date: 2018.06

  • Controlled Radical Polymerization in Photo-curing toward Unique Graded Nanostructures 招待有

    Takeo Suga  [Invited]

    The 35th International Conference of Photopolymer Science and Technology  (Makuhari)  The Society of Photopolymer Science and Technology (SPST)

    Presentation date: 2018.06

  • 有機蓄電デバイスに向けた材料設計 招待有

    須賀健雄  [Invited]

    有機エレクトロニクス研究会 第229回研究会  (新宿)  有機エレクトロニクス研究会

    Presentation date: 2018.06

  • Photo-driven Controlled Radical Polymerization for Gradient Nanodomain Formation 招待有

    Takeo Suga  [Invited]

    International Conference of Polymer Chemistry, PC2016  (Changchun) 

    Presentation date: 2018.05

  • Bicontinuous Hard-Soft Nanodomain Formation via Controlled Photo-curing

    Takeo Suga, Kaname Takata, Hiroyo Sumida, Hiroyuki Nishide  [Invited]

    67th SPSJ Annual Meeting  (Nagoya)  The Society of Polymer Science, Japan (SPSJ)

    Presentation date: 2018.05

  • Controlled Radical Polymerization in Photo-curing toward Unique Graded Nanostructures 招待有

    Takeo Suga, Eigo Ando, Hiroyuki Nishide  [Invited]

    Emerging Polymer Technology Summit 17 (EPTS17)  (Melbourne) 

    Presentation date: 2017.11

  • 両性イオンポリマーの表面偏析・形成による超親水性コート剤の開発 招待有

    須賀健雄  [Invited]

    高分子同友会  (東京)  高分子学会

    Presentation date: 2017.11

  • Bicontinuous, Graded Nanodomain Formation: Precise Photo-Curing and Post-functionalization

    Takeo SUGA, Eigo ANDO, Yusuke SAHASHI, Hiroyuki NISHIDE

    66th Symposium on Macromolecules  (Matsuyama) 

    Presentation date: 2017.09

  • Controlled Radical Polymerization in Photo-curing toward Unique Graded Nanostructures 招待有

    Takeo Suga  [Invited]

    Japan-Taiwan Bilateral Polymer Symposium (JTBPS2017)  (Yonezawa) 

    Presentation date: 2017.09

  • Controlled Radical Polymerization in Photo-curing toward Unique Graded Nanostructures

    Takeo Suga, Eigo Ando, Kaname Takata, Hiroyuki Nishide

    IUPAC 17th International Symposium on MacroMolecular Complexes (MMC-17)  (Tokyo) 

    Presentation date: 2017.08

  • 気相重合を用いた共役高分子のその場形成と電荷貯蔵・輸送材料への展開 招待有

     [Invited]

    (Tokyo)  The Society of Polymer Science, Japan (SPSJ)

    Presentation date: 2017.06

  • 両性イオンポリマーの表面偏析に基づく超親水性コート剤の開発

    須賀健雄

    JST 早稲田大学 新技術説明会  (東京)  JST

    Presentation date: 2017.05

  • Superhydrophilic Zwitterion Formation in the Diamine Polymer Coatings via CO2 Capture under Water

    Takeo SUGA, Matsutaro KOBAYASHI, Yusuke SAHASHI, Hiroyuki NISHIDE

    66th SPSJ Annual Meeting  The Society of Polymer Science, Japan (SPSJ)

    Presentation date: 2017.05

  • Controlled Radical Polymerization in Photo-curing toward Unique Graded Nanostructures 招待有

    Takeo Suga  [Invited]

    日本化学会第97春季年会 アジア国際シンポジウム高分子ディビジョン  (Yokohama)  CSJ

    Presentation date: 2017.03

  • Nanodomain Control in Photo-cured Coatings via Precise Polymerization Techniques 招待有

    T. Suga, K. Katayama, E. Ando, H. Nishide  [Invited]

    RadTech Asia 2016  (Tokyo) 

    Presentation date: 2016.12

  • Gradient Nanodomain Formation in Controlled Photo-curing toward Hybrid Materials 招待有

    T. Suga, K. Minamibayashi, H. Nishide  [Invited]

    14th Pacific Polymer Conference (PPC2015)  (Kauai) 

    Presentation date: 2015.12

  • 気相重合による元素ブロック高分子の創製と機能展開 招待有

    須賀健雄  [Invited]

    第64回高分子学会年次大会  (札幌)  高分子学会

    Presentation date: 2015.05

  • Design of Fluorescent Coatings for High-Sensitive Optical CO2 Detection 招待有

    Suga, T, Nagayama, A, Inukai, J, Watanabe, M, Nishide, H

    The 15th IUMRS-International Conference in Asia (IUMRS-ICA 2014)  (Fukuoka) 

    Presentation date: 2014.08

  • Polymer/Polythiophene Composite Materials via Vapor-phase Polymerization toward a Totally Organic Rechargeable Battery 招待有

    Presentation date: 2011.05

  • “Redox-Active Radical Polymers for Rapid Charge-Storage and -Transport” (invited talk)

    241st ACS National Meeting & Exposition, Anaheim, CA, United States 

    Presentation date: 2011.03

  • 「有機ポリマー電池」

    早稲田大学ナノテクノロジーフォーラムジョイントフェア2010 

    Presentation date: 2010.11

  • Redox-Active Radical Polymers for Charge-Storage/Transport Materials: Organic Rechargeable Battery and Memory Applications

    THE 4th INTERNATIONAL SYMPOSIUM ON POLYMER MATERIALS SCIENCE (Gaithersburg, USA) 

    Presentation date: 2010.10

  • Redox-Active Radicals in Self-Assembled Block Copolymer “Playground”: New Approaches toward Organic Nonvolatile Memory

    THE 4th INTERNATIONAL SYMPOSIUM ON POLYMER MATERIALS SCIENCE (Gaithersburg, USA) 

    Presentation date: 2010.10

  • Self-Assembled Radical/Ionic-Domain Formation toward Organic Thin Film Device

    Presentation date: 2010.09

  • Functional Materials in Self-Assembled Block Copolymer “Playground”: New Approaches toward Organic Nonvolatile Memory and Optical Sensor

    IUPAC Macro Congress 2010 

    Presentation date: 2010.07

  • Self-Assembled, Radical/Ion-Containing Block Copolymers for Electronics Applications

    International Symposium of Polymer Chemistry 2010 (PC2010) (Suzhou, China) 

    Presentation date: 2010.06

  • ラジカル/イオン含有相分離膜の構築と電荷蓄積・輸送

    10−1超分子研究会「電荷分離・輸送材料を指向した超分子デザイン」依頼講演 

    Presentation date: 2010.05

  • 精密ラジカル重合によるラジカル/イオン含有ブロック共重合体の合成と相分離構造

    第59回高分子学会年次大会(横浜) 

    Presentation date: 2010.05

  • ラジカル/イオン含有ミクロ相分離膜の有機メモリ素子への応用

    日本化学会第90回春季年会 ATPプログラム 

    Presentation date: 2010.03

  • Radical-Containing Block Polyelectrolytes: Synthesis, Morphology, and Charge Storage/Transport Modulation in the Organic Thin Film Devices

    FAPS (The Federations of Asian Polymer Societies) 1st Polymer Congress, selected as Young Scientist Poster Award 

    Presentation date: 2009.10

  • ラジカル/イオン含有ブロック共重合体のミクロ相分離構造と有機薄膜素子における電荷蓄積・輸送

    高分子学会討論会 

    Presentation date: 2009.09

  • Radical Polymers for Organic-Based Rechargeable Device

    The Polymers Gordon Research Conference 

    Presentation date: 2009.06

  • Radical Polymers for Organic-Based Thin Film Devices (selected as one of Top 2 Oral presenation)

    Gordon-Kenan Research Seminar 

    Presentation date: 2009.06

  • Electric and Dielectric Properties of the TEMPO/Oxoammonium Salt-Substituted Polymer Thin Film Devices

    Presentation date: 2009.05

  • Block Copolymers Bearing Stable Radicals and their Microphase Separation

    Presentation date: 2009.05

  • Synthesis and Characterization of Diazocine-Containing Poly(arylene ether sulfone: Correlation of Mechanical Properties with Local Chain Motion

    Polycondensation2008 

    Presentation date: 2008.09

  • Nitroxide-Containing Block Copolymers: Synthesis and Morphological Investigation

    US-Japan Polymat 2008 Summit 

    Presentation date: 2008.08

  • Block Copolymers Containing Stable Free Radicals: Synthesis and Magnetic Force Microscopic Morphological Investigations

    ACS National Spring Meeting 

    Presentation date: 2008.04

  • Synthesis of Diazocine-Containing Polysulfones and their Mechanical and Electrochemical Properties

    ACS National Spring Meeting 

    Presentation date: 2008.04

  • Synthesis of Photosensitive Poly(Arylene Imide Sulfone)s

    ACS National Spring Meeting 

    Presentation date: 2008.04

  • Adaptive Material Design for Smart Marine Coatings

    Takeo Suga

▼display all

Specific Research

  • CO2固定反応に基づく表面超親水化と自己洗浄性塗料への展開

    2019  

     View Summary

    水に浸漬するだけで僅かな水中濃度(300 ppm)のCO2を自発的に取り込み、海洋生物の付着防止に有効な超親水性を発現する高分子コーティングの創出を目的とした。アミン類への可逆なCO2付加に対し、近接アミンを配したジアミン構造のうち、1,2級, 1,3級及び2,3級ジアミンを置換したポリマーにおいて、分子内での両性イオンの形成によるCO2捕捉・保持能の飛躍的な向上と超親水化を明らかにした。海水浸漬試験と合わせ、中性子反射法による固液界面でのCO2取込みによる水和膨潤層の形成過程の描像し、CO2をtriggerとして繰り返し超親水化する環境「適応」型の防汚表面として提示した。

  • 精密重合によるUV硬化の新開拓:ナノ構造の同時形成と機能コーティングへの応用

    2018  

     View Summary

    迅速なUV硬化反応に敢えて「光駆動型」の精密ラジカル重合機構を組み込み、共連続傾斜ミクロドメイン構造を同時形成する手法を、ドメインのサイズ、深さ分布・化学組成の傾斜制御、ナノ粒子の傾斜配置など基盤技術として深化し、機能展開へ繋ぐことを目的とした。具体的には、(1)末端アクリレート1分子停止法の確立により、各種置換基や両末端を規定したテレケリック型高分子ドーマントの合成、(2)ミクロドメインのサイズ制御因子として、架橋剤濃度に加え、第二モノマーの反応性と熱の影響が大きいこと、(3)各種フィラーをドメイン選択的に配置し、表面濡れ性や低反射性を付与、を明らかにした。

  • 自発的CO2固定に基づく環境調和型コーティングの創出

    2016  

     View Summary

    超親水性を示す高分子コーティング材料は、生体適合性や防汚性の機能性コーティングとして広く期待されている。本研究では、内部の疎水性を保ちつつ表面のみ両性イオン化することで、超親水性と機械強度をあわせ持つコーティング材料として提案した。特にジアミン誘導体へのCO2の付加反応に着目し、級数、スペーサー数を最適化することでCO2付加体の安定性を飛躍的に向上した。ジアミンポリマーを添加したエポキシ熱硬化膜では、CO2通気だけでなく、大気開放下、水浸漬するだけでも水中の微量CO2によりコーティング表面を超親水化できることを明らかにした。

  • 反応性ブロック型高分子の合成と機能化

    2013  

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    1. 研究目的 ラジカル・イオンを用いた有機メモリ特性の発現には、モルフォロジーの制御と機能部位の選択的なドメイン配置が鍵となる。本研究課題では、Click反応を用いてラジカル/イオンを任意の割合で導入、共存させたブロック共重合体の合成、AFMによる相分離構造解析およびI-V特性の評価を目的とする。またControl実験としてペンタフルオロフェニルエステルを有する単独重合体にラジカル/イオンを導入したランダム共重合体の合成およびI-V特性も合わせて報告する。2. アミノ基修飾イオン液体の合成とClick反応 1-メチルイミダゾールに2-ブロモエチルアミン臭化水素塩を反応させイミダゾリウム塩へと誘導後、PF6塩にアニオン交換した。中和によりアミノ基を遊離させるとイミダゾリウムからプロトン脱離によるカルベンの副生が示唆されたため、Click反応時にin-situで中和することにした。RAFT重合により得られた活性エステル(PFPA)含有ブロック共重合体(PS-PFPA)のDMF溶液にアミノ-TEMPO(PFPAに対し1当量以下、例えば0.9, 0.6当量)とトリエチルアミンを加え反応させることで、予めPFPAドメインにランダムにTEMPO基を導入した。次にone-potでアミノ基修飾イオン液体を大過剰加え未反応PFPA部位にイオン液体部を導入した。TEMPOラジカル/イオン液体部位の組成比は仕込み比で自在に調整でき、PS-PFPAのセグメント長の制御と合わせ、多様な機能性ブロック共重合体の精密合成に成功した。3. ミクロ相分離挙動とメモリ特性 イオンのみもしくはラジカル/イオン(0.70/0.30)を導入したポリマーでは、10~15nmのスフィア型の相分離構造が得られたが、ラジカルの比率の増加に伴いポリスチレンドメインとの相溶性が向上し、ラジカルのみを導入したポリマーでは明瞭なスフィア構造ではなく、凝集構造が観察された。ITO電極上にスフィア型の機能性ブロック共重合体を成膜し(100 nm)、Alを蒸着した素子では、ラジカル/イオンが共存する場合の電流電圧特性で、-2 V付近を閾値電圧としてON状態へスイッチし、ヒステリシス曲線を描いた(WORM型, ON/OFF比 10^3)。一方、ラジカルのみ、イオンのみの場合はスイッチングを示さなかった。これより、同一ドメイン内にラジカルとイオンが共存している場合のみメモリ特性を示すという従来の知見を支持した。また、ON状態、OFF状態をそれぞれ16時間以上保持した。以上、ラジカル/イオン共存型のミクロ相分離ドメイン構造の形成を目的として、Click反応を組み込んだ機能性ブロック共重合体の精密合成法を確立するとともに、メモリ素子としての特性を明らかにした。

  • イオン液体を用いた機能分子のミクロ相分離構造への選択集積

    2012  

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     汎用ブロック共重合体(例えばPS-b-PEO)が自己組織化して形成する多様なミクロ相分離構造への機能部位の創り込みは、電荷輸送・分離界面を構築する手法として提案できる。これまでにラジカル/イオンを含むミクロドメイン構造の違いにより、例えばスフィア型では繰返し書込み可能なメモリ特性、シリンダー型では1回書込み型のメモリ特性を示し、水平ラメラ型ではメモリ特性が現れない、などメモリ特性の創り分けが可能なことを報告してきた。本研究では、メモリ特性の発現には酸化還元能を有するラジカルと電荷補償イオンとの界面構築が重要な因子と捉え、PS-b-PEOが形成するミクロ相分離構造への機能部位の選択的集積化(配置)を検討した。また、そのときに発現するメモリ特性を相分離構造と相関させて評価した。 機能部位として安定かつ迅速な電荷授受能を有するTEMPOラジカルを選択し、イオン液体部位(IL)を結合した誘導体1とILを持たない誘導体2を合成、マトリクスとしてスフィア型のポリ(スチレン-b-エチレンオキサイド)(PS-b-PEO)へと添加した。このときの相分離構造の変化をDSC, AFM, TEM, SAXS及び固体NMRにより解析した。PS-b-PEOへの1の添加では、PEOセグメントの結晶融解ピークの消失、PEOドメインサイズの増大などから1のPEOドメインへの選択配置を支持した。対称的に、2の添加では結晶融解ピークは消失せず、PEOドメイン間隔の増大などから2のPSドメインへの選択配置を支持し、以上の結果より機能性分子のドメイン選択的な配置が可能であることを明らかにした。また、1のみ10 wt%添加、および2とILを各々10 wt%添加したPS-b-PEOをそれぞれITO基板へ成膜し、アニーリング後、Alを蒸着することで単層有機メモリ素子を作製した。1を添加した素子では繰り返し書き換え可能なメモリ特性が、2とILをそれぞれ10 wt%添加した素子では一回書込み型(WORM)のメモリ特性が得られ、同一ドメイン中におけるTEMPOとイオン液体の共存の有無が発現するメモリ特性に影響することを明らかにした。一部、独・Max Planck研究所との共同研究として走査プローブ顕微鏡を用いた局所(ドメイン)導電性変化についても観測し、メモリ特性の発現機構への足がかりを得た。

  • 気固界面における反応集積化と有機電子材料の創出

    2012  

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     電荷蓄積能を持つp, n型レドックスポリマー存在下で、その場(in-situ)重合により導電性高分子(PEDOT, PEDOP)を形成することで、高容量かつフレキシブルな有機複合電極の創出を目的とする。本研究ではin-situ重合法として気相酸化重合および電解酸化重合を比較しながら、得られた複合層の電荷蓄積・輸送能について考察した。また、その場重合を有機半導体(ドナー材料)の調製法として提案し、アクセプターとの複合化による光電変換層の構築も試みた。1) p, n型ラジカルポリマーとの複合化とフレキシブル全有機二次電池の作製 気相酸化重合はラジカル機構で進行するため、TEMPO存在下では重合阻害される。過剰量の酸化剤p-トルエンスルホン酸鉄(III) (Fe(OTs)3)で予めTEMPOをオキソアンモニウムカチオンへと誘導後、基材(ガラス基板、PET不織布など)に成膜、EDOT雰囲気下で気相重合した(70°C, 60 min.)。電解酸化重合では、TEMPOが酸化される1.5 V vs. Ag/AgClを定電位印加し、その上でEDOTを供給、重合させることで複合膜を得た。得られたPEDOT/PTAm(1/3 w/w)複合膜の放電曲線では、120 C rate(30秒での高速充電に対応)においても理論容量を維持した。PEDOT組成の増加にともない出力特性が向上し、交流インピーダンス測定からも電荷移動抵抗の減少が見られたことから、PEDOTを介した電荷輸送の促進が支持された。 PET不織布上に形成したPEDOT/PTAm, PEDOT/PGSt複合膜をそれぞれ正・負極として、電解液としてイオン液体1-ブチル-3-メチルイミダゾリウムテトラフルオロボラート(BmimBF4)を含むセパレーターを挟み、ラミネートしてフレキシブルな全有機電池を作製した。両レドックスポリマーの酸化還元電位差に相当する0.67 Vにプラトー電位を示し、繰り返し安定な充放電挙動を示す二次電池として作動することを明らかにした。2) 気相重合を用いたドナー層の構築と光電変換素子の作製 ITO基板上にホール輸送層としてPEDOT/PSS水分散液を成膜後、酸化剤溶液(Fe(OTs)3/BuOH(1, 7, 10 wt%))を塗布しターチオフェンを気相重合した。エタノール洗浄、ヒドラジンによる脱ドープを経て、ドナー層として無置換ポリチオフェンを得た。アクセプター層としてPCBM/モノクロロベンゼン溶液を積層後、ホールブロッキング層としてTiOxを形成、Alを真空蒸着して積層型素子を作製した。また、PCBMと酸化剤を塗布し、気相重合させることによってドナー・アクセプター混合(BHJ)型素子も合わせて作製した。各層の膜厚最適化およびアクセプターとして吸光度、溶解性の高いPC71BMを用いることで、積層型素子の1 Sun照射下におけるJ-V測定より変換効率η = 0.63 %を示した。また、無置換ポリチオフェンから低バンドギャップ性のポリベンゾチアジアゾールへの拡張を試み、新たなドナー層構築法としての気相重合の可能性を見出した。 以上の成果を元に、新学術領域研究(元素ブロック)に申請し、無事採択された(2013.4.)。

  • ニトロキシド置換ポリノルボルネンの合成と有機ラジカル薄型電池への応用

    2006  

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    (1) 光架橋ラジカルポリマーの合成と薄型二次電池への応用 電極としての成形性を付与させるため、TEMPO置換ポリノルボルネンを合成、光架橋を適用した。ノルボルネンジカルボン酸無水物を出発物として4-ヒドロキシ-TEMPOを反応させジエステルへ誘導、Grubbs触媒を用いて開環メタセシス重合し、高分子量体(分子量約2万)を得た。得られた高分子はTHF、クロロホルムなど有機溶媒に可溶で、高い成膜性を有した。ポリノルボルネンの主鎖オレフィン部位へ選択的にビスアジド誘導体を光付加させ、ラジカル部位の損傷なく架橋ラジカル薄膜を得た。ラジカル薄膜はアノード側約0.8 V対Ag/AgClにTEMPOのp型酸化還元対に由来する安定な酸化還元波を示し、膜厚250 nmまで導電補助剤なしでも迅速かつ定量的な電子授受が可能であることを明らかにした。光パターニングにより膜厚、形状を制御したラジカル薄膜が得られ、薄型かつ柔軟なペーパー電池につながることを実証した。(2) n型ラジカルポリマーの合成と全有機二次電池への展開  n型の酸化還元能を有するガルビノキシルラジカルに着目し、負極活物質として全有機二次電池へ適用した。シリル保護したブロモフェノール誘導体をリチオ化、4-ブロモ-1-メチルベンゾエートと反応させガルビノキシ骨格を構築した。Stilleカップリングによりスチレンモノマーへと誘導し、二官能性アクリレートとラジカル共重合させることにより架橋、化学酸化を経てポリ(ガルビノキシルスチレン)を得た。塩基性下、0.1 V (対Ag/AgCl)にn型の酸化還元波を示し、TEMPO置換ポリノルボルネン正極と組み合わせ試作した電池では、それぞれの酸化還元電位の差に対応する0.7 Vに電位平坦部が現れ、両極とも有機ラジカルから成る二次電池の動作をはじめて実証できた。

  • ニトロキシドラジカルポリマーの合成と有機ラジカル電池への展開

    2005  

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    1. n型ラジカルポリマーの合成と酸化還元挙動 ニトロキシドのo-位に電子吸引基としてトリフルオロメチル基を置換したスチレン誘導体を合成し、ラジカル重合、脱保護・化学酸化を経てラジカルポリマーへ誘導した。CVよりカソード側-0.76 Vにn型の酸化還元波が現れ、繰り返し掃引しても安定であった。無置換誘導体ではp型レドックスを示すことより、置換基の電子効果によりレドックス対の選択が可能であることを実証した。n型高分子で作製した炭素複合電極は、溶液と異なり不可逆な酸化還元挙動を示した。定電位電解、電解ESR、電解UV測定より安定性を検証中である。2. ラジカル高分子層における電子・物質(対イオン)移動過程の解析  TEMPO置換ポリメタクリレートから成る高分子被覆電極(膜厚2x10-6m)のCVは、ピーク電位幅狭く、電気化学パルス法から高分子膜中における電荷の見かけの拡散係数Dappは10-8 (cm2/s)桁と見積もられ、高分子膜内においても速い電子移動を明らかにした。複合電極の走査電顕像より炭素繊維の周り約100 nm厚みで高分子が覆う形態が観察され、高分子層内をホッピングして電子伝達されていることが示唆された。3. TEMPO置換ポリグリシジルエーテルの合成と電気化学特性 高容量かつ電解質との相容性が期待できるポリエーテルを主鎖に選択、TEMPOを側鎖に置換したラジカルポリマーを分子設計、アニオン開環重合により分子量約3万の高分子量体を得た。ラジカルポリマー/炭素複合電極を正極、リチウム負極とした試作セルは、3.7 Vにプラトー電位、100サイクル後も安定した充放電挙動を示し、電極活物質としてきわめて安定であることを明らかにした。 今後は、選ばれたラジカルポリマーの電極・セル評価を進めるとともに、n型レドックス能を有するラジカルポリマーを分子設計・精密合成し、全有機から成る薄型フレキシブルな電池実現を目指し展開予定である。

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Syllabus

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Teaching Experience

  • Advanced Physical Chemistry of Polymeric Materials

    Waseda University, School of Advanced Science and Engineering  

    2021.04
    -
    Now
     

  • Functional Polymer Chemistry

    Waseda University, School of Advanced Science and Engineering  

    2021.04
    -
    Now
     

  • Industrial Chemistry

    Waseda University, School of Advanced Science and Engineering  

    2019.04
    -
    Now
     

  • Advanced Physical Chemistry B

    Waseda University, School of Advanced Science and Engineering  

    2016.04
    -
    Now
     

  • Fundamentals of Materials Chemistry

    Waseda University, School of Advanced Science and Engineering  

    2016.04
    -
    Now
     

  • Polymer Chemistry

    School of Advanced Science and Engineering  

    2016.04
    -
    Now
     

  • Practice in Applied Chemistry A

    School of Advanced Science and Engineering  

    2012.04
    -
    Now
     

  • Organic Chemistry A

    School of Advanced Science and Engineering  

    2012.04
    -
    Now
     

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Committee Memberships

  • 2021.01
    -
    Now

    Kanto Branch, The Chemical Society of Japan  Secretary

  • 2020.06
    -
    Now

    The Society of Polymer Science, Japan  Event committee

  • 2019.06
    -
    2021.05

    The Society of Polymer Science, Japan  Editorial board

  • 2013.03
    -
    2019.03

    関東高分子若手研究会  世話人

  • 2017.05
    -
     

    高分子学会  代議員

  • 2017.01
    -
     

    ラドテック研究会  幹事(理事)

  • 2016.11
    -
     

    高分子学会  関東支部23区地区幹事

  • 2006.03
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    関東高分子若手研究会  世話人

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Media Coverage

  • New Development of UV-curing Technology in View of Morphological Control

    Newspaper, magazine

    Author: Myself  

    Japan Chemical Daily Co.   Japan Chemical Daily  

    p7 (Special Issue on UV/EB technology)  

    2020.09

  • Fostering Future Memory Technology through Collaborative Platform

    Other

    Author: Other  

    Asahi Shimbun  

    p35-36  

    2020.03

  • Practical Development of Self-Cleaning Coatings for Aircraft Carriers

    Newspaper, magazine

    Author: Other  

    Japan Chemical Daily Co.   Japan Chemical Daily  

    2019.08