2024/01/31 更新

写真a

ウベ トオル
宇部 達
Ube Toru
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研究開発機構 機構准教授
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学位

  • 博士(工学) ( 京都大学 )

学歴

  • 2011年3月
     

    京都大学   工学研究科   高分子化学専攻   博士後期   修了

論文

  • Inducing Motions of Polymers in Liquid Nitrogen with Light

    Toru Ube, Ikumi Suka, Shunya Ogikubo, Gaku Hashimoto, Masayuki Suda, Hiroshi M. Yamamoto, Tomiki Ikeda

    Advanced Materials   35 ( 47 )   2306402   2023年10月

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    掲載種別:研究論文(学術雑誌)   出版者・発行元:Wiley  

    Abstract

    Polymer materials that show macroscopic deformation in response to external stimuli are feasible for novel soft actuators including microactuators. Incorporation of photochromic moieties, such as azobenzenes, into polymer networks enables macroscopic deformation under irradiation with light through photoisomerization. Under cryogenic conditions, however, it has been difficult to induce macroscopic deformation as polymers lose their soft nature due to the severe restrictions of molecular motions. Here, activation of molecular motions and macroscopic deformation in liquid nitrogen only with light for polymers containing photochromic moieties is reported. Photoinduced bending of polymer networks with normal azobenzenes in liquid nitrogen is enabled by preliminary UV irradiation at room temperature to produce cis‐isomers. To realize photoinduced deformation directly in liquid nitrogen, polymer networks are functionalized with bridged azobenzenes, which exist as cis‐isomers in thermodynamic equilibrium. The films with bridged azobenzenes exhibit reversible photoisomerization and bending upon irradiation with light in liquid nitrogen without the need of preliminary irradiation, implying that the change in conformation of polymer chains can be isothermally induced even under cryogenic conditions. Achievement of flexible motions under cryogenic conditions through isothermal processes will greatly expand the operating temperature range of soft actuators.

    DOI: 10.1002/adma.202306402

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  • Shape programming and photoactuation of interpenetrating polymer networks containing azobenzene moieties

    Toru Ube, Keigo Naito, Tomiki Ikeda

    JOURNAL OF MATERIALS CHEMISTRY C   11 ( 24 )   8100 - 8106   2022年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ROYAL SOC CHEMISTRY  

    Crosslinked liquid-crystalline polymers (LCPs) with photochromic moieties exhibit macroscopic deformation upon irradiation with light. Controlling the 3D shapes of crosslinked LCPs leads to fabrication of photoactuators with desired structures and functions. Here, we investigate the shape memory effects and photoinduced deformation of interpenetrating polymer network (IPN) films composed of azobenzene LCP (PAzo) and poly(methyl methacrylate) (PMMA). PAzo/PMMA IPN films could be temporarily programmed into desired 3D structures with the aid of glass transition. The IPN films with temporary shapes showed high thermal stability compared to pristine PAzo films, which is ascribed to the gradual glass transition behaviour over a wide temperature range. The shape-programmed IPN samples showed various reversible deformation behaviours depending on the programmed shapes upon irradiation with UV and visible light. Furthermore, the thermal stability of temporary shapes allowed reversible photoactuation of shape-programmed samples at elevated temperatures as high as 100 degrees C. Formation of IPN films is a promising approach to enhance the design and functions of photoactuators consisting of crosslinked LCPs.

    DOI: 10.1039/d2tc04067k

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  • Sunlight-driven smart windows with polymer/liquid crystal composites for autonomous control of optical properties

    Toru Ube, Jumpei Imai, Marie Yoshida, Toru Fujisawa, Hiroshi Hasebe, Haruyoshi Takatsu, Tomiki Ikeda

    JOURNAL OF MATERIALS CHEMISTRY C   10 ( 35 )   12789 - 12794   2022年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ROYAL SOC CHEMISTRY  

    We developed optically switchable smart windows driven by sunlight with polymer/liquid crystal (LC) composites containing azobenzene derivatives, which undergo trans-cis isomerization with high efficiency under sunlight. The composites exhibited high transparency in the initial state owing to homeotropic alignment of LCs, which was stabilized by polymer networks. Optical switching from the tranparent state to a light-scattering state was induced isothermally upon exposure to sunlight due to smectic A (SmA) to chiral nematic (N*) phase transition of LCs, triggered by trans-cis photoisomerization of the azobenzenes. The initial transparent state was restored in the absence of sunlight, resulting from N* to SmA phase transition induced by thermal cis-trans back isomerization of the azobenzenes. These autonomic smart windows utilizing only sunlight can be ubiquitously installed without additional artificial sources of energy.

    DOI: 10.1039/d2tc02754b

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  • Photoinduced Motions of Thermoplastic Polyurethanes Containing Azobenzene Moieties in Main Chains

    Toru Ube, Romu Nakayama, Tomiki Ikeda

    MACROMOLECULES   55 ( 2 )   413 - 420   2022年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER CHEMICAL SOC  

    Thermoplastic polyurethane containing azobenzene moieties in main chains was developed for photomobile materials capable of reversible photoactuation and shape programming, and was characterized for phase transition properties, microstructures, and photoinduced deformation behaviors. Photomobile films with glassy nature could be fabricated using both melt- and solution-processing methods, in contrast with conventional photomobile materials consisting of chemically cross-linked networks. The alignment of azobenzene moieties and macroscopic shapes in the initial states were controlled by external force under heating above glass transition temperature, which were stabilized by the formation of physical cross-links through hydrogen bonding interactions. The films with uniaxial alignment of azobenzene moieties showed reversible bending upon irradiation with UV and visible light, which could be repeated for 100 cycles. Physical cross-links in the present system can be an alternative for covalent cross-links in photomobile polymer materials, expanding the variety of designs with superior processability.

    DOI: 10.1021/acs.macromol.1c01827

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  • Photoalignment in Polysiloxane Liquid-Crystalline Elastomers with Rearrangeable Networks

    Toru Ube, Haruna Tsunoda, Kyohei Kawasaki, Tomiki Ikeda

    ADVANCED OPTICAL MATERIALS   9 ( 9 )   2100053   2021年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:WILEY-V C H VERLAG GMBH  

    Molecular alignment in liquid-crystalline elastomers with polysiloxane backbone is controlled with the aid of photoalignment and exchangeable links to enhance performance as photoactuators. The photoalignment is triggered by trans-cis-trans isomerization of azobenzene moieties, which are introduced at crosslinking points, upon irradiation with linearly polarized UV (LPUV) light under heating. The induced alignment is memorized by rearrangement of network structures through exchange reactions of covalent bonds. When irradiated with LPUV light, freestanding films show bending along with the alignment change in surface regions. Macroscopic shapes are also rememorized by exchange reactions at crosslinks. Combination of photoalignment and network rearrangement allows continuous deformation of freestanding films upon exposure to LPUV light with varying polarization directions. This approach enhances the degree of freedom in alignment control, photoactuation, and reshaping of polysiloxane-based liquid-crystalline elastomers, which are feasible as soft actuators.

    DOI: 10.1002/adom.202100053

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  • Photomobile Polymer Materials with Complex 3D Deformation, Continuous Motions, Self-Regulation, and Enhanced Processability

    Toru Ube, Tomiki Ikeda

    ADVANCED OPTICAL MATERIALS   7 ( 16 )   1900380   2019年8月

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    記述言語:英語   出版者・発行元:WILEY-V C H VERLAG GMBH  

    Liquid-crystalline polymers with photodeformable properties have been extensively studied due to their ability of wireless conversion of light energy into mechanical work. With the development of crosslinked liquid-crystalline polymers, various 3D motions, such as bending, twisting, oscillation, rotation, and translational motion have been successfully induced. Recent trends for developing soft robots and microrobots accelerate the progress of photomobile polymer materials. This review is focused on recent advances in the field of photomobile materials based on liquid-crystalline polymers. The structure-function relationship in photomobile polymer materials is overviewed, and the progress in recent years is detailed in terms of complex 3D deformation, continuous motions, self-regulation, and processability.

    DOI: 10.1002/adom.201900380

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  • Interpenetrating polymer networks of liquid-crystalline azobenzene polymers and poly(dimethylsiloxane) as photomobile materials

    T. Ube, K. Minagawa, T. Ikeda

    SOFT MATTER   13 ( 35 )   5820 - 5823   2017年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ROYAL SOC CHEMISTRY  

    We developed photomobile polymer materials with interpenetrating polymer network (IPN) structures composed of crosslinked liquid-crystalline azobenzene polymer (PAzo) and poly(dimethylsiloxane) (PDMS). By introducing PDMS into a PAzo template network, IPN was formed without disturbing the alignment of mesogens in the PAzo network. The films showed macroscopic bending behavior upon irradiation with UV and visible light. Although the IPN film showed a phase separated structure, the bending speed was significantly enhanced compared with the pristine film of PAzo, thanks to the soft nature of PDMS. The present method of preparing IPNs can be a promising approach to combine PAzo with various polymers and enhance the mechanical and photoresponsive properties.

    DOI: 10.1039/c7sm01412k

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  • A block copolymer of crosslinkable polythiophene and removable poly(ethylene oxide) for preparing heterostructures of organic semiconductors

    T. Ube, T. Kosaka, H. Okazaki, K. Nakae, T. Ikeda

    JOURNAL OF MATERIALS CHEMISTRY C   5 ( 6 )   1414 - 1419   2017年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ROYAL SOC CHEMISTRY  

    We prepared a block copolymer composed of polythiophene (PT) with cinnamate groups and poly(ethylene oxide) (PEO), which are connected through a cleavable acetal bond, aiming at constructing donor/acceptor heterostructures through post deposition of acceptor molecules into donor template networks. The block copolymer films showed phase-separated structures with domain sizes of 10-100 nm. Irradiation with UV light afforded crosslinked films through [2+2] cyclodimerization of cinnamate groups. Then, PEO was removed by acidic cleavage of the acetal bond, yielding PT template networks. Taking advantage of the insoluble networks, a fullerene derivative was deposited into the PT templates through a spin-coating process to form donor/acceptor heterostructures. The introduction of the fullerene derivative was confirmed by UV-Vis absorption and fluorescence spectroscopy. This strategy of depositing acceptor molecules into donor template networks, instead of spin-coating from donor/acceptor blend solutions, could be applied to improve the phase-separated structures and power conversion efficiencies of polymer solar cells.

    DOI: 10.1039/c6tc04409c

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  • Photomobile Liquid-Crystalline Elastomers with Rearrangeable Networks

    Toru Ube, Kyohei Kawasaki, Tomiki Ikeda

    ADVANCED MATERIALS   28 ( 37 )   8212 - 8217   2016年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:WILEY-V C H VERLAG GMBH  

    Incorporation of dynamic covalent bonds into photomobile liquid-crystalline elastomers with a polysiloxane backbone enables the alignment of mesogens and macroscopic shapes to be controlled through the rearrangement of the network topology, even after the formation of chemically crosslinked networks. The reshaped samples show various sophisticated 3D motions upon irradiation with UV and visible light, depending on their initial shapes.

    DOI: 10.1002/adma.201602745

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  • Photomobile materials with interpenetrating polymer networks composed of liquid-crystalline and amorphous polymers

    T. Ube, K. Takado, T. Ikeda

    JOURNAL OF MATERIALS CHEMISTRY C   3 ( 31 )   8006 - 8009   2015年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ROYAL SOC CHEMISTRY  

    We developed interpenetrating polymer networks (IPNs) composed of a crosslinked azobenzene liquid-crystalline polymer (PAzo) and poly(alkyl methacrylate)s (PAMAs). When irradiated with UV and visible light, the IPN films showed reversible bending. The photo-responsive and mechanical properties of PAzo films were significantly enhanced by incorporation of the PAMA components.

    DOI: 10.1039/c5tc01489a

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  • Photomobile Polymer Materials with Crosslinked Liquid-Crystalline Structures: Molecular Design, Fabrication, and Functions

    Toru Ube, Tomiki Ikeda

    ANGEWANDTE CHEMIE-INTERNATIONAL EDITION   53 ( 39 )   10290 - 10299   2014年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:WILEY-V C H VERLAG GMBH  

    Crosslinked liquid-crystalline polymer materials that macroscopically deform when irradiated with light have been extensively studied in the past decade because of their potential in various applications, such as microactuators and microfluidic devices. The basic motions of these materials are contraction-expansion and bending-unbending, which are observed mainly in polysiloxanes and polyacrylates that contain photochromic moieties. Other sophisticated motions such as twisting, oscillation, rotation, and translational motion have also been achieved. In recent years, efforts have been made to improve the photoresponsive and mechanical properties of this novel class of materials through the modification of molecular structures, development of new fabrication methods, and construction of composite structures. Herein, we review structures, functions, and working mechanisms of photomobile materials and recent advances in this field.

    DOI: 10.1002/anie.201400513

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  • Relaxation of Single Polymer Chain in Poly(methyl methacrylate) Films under Uniaxial Extension Observed by Scanning Near-Field Optical Microscopy

    Toru Ube, Hiroyuki Aoki, Shinzaburo Ito, Jun-ichi Horinaka, Toshikazu Takigawa, Toshiro Masuda

    MACROMOLECULES   44 ( 11 )   4445 - 4451   2011年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER CHEMICAL SOC  

    Single chain conformations during the stress relaxation process in uniaxially stretched poly(methyl methacrylate) (PMMA) films were observed in real space by scanning near-field optical microscopy (SNOM). The extension ratio at the molecular level was directly evaluated from the SNOM images and compared with the macroscopic stress relaxation. At the early stage of the relaxation process, the whole single chain retained the stretched conformation in spite of the decrease in, stress. This suggests that the fast relaxation in stress is caused by the local conformational change at the length scale much smaller than the entire chain length. The experimental data were successfully explained by the contraction of the primitive chain contour in the Doi-Edwards model. Furthermore, the distribution function of the chain dimension was found to retain its shape during the relaxation process, indicating that the conformational relaxation of polymer chain is rather homogeneous in the well-entangled system.

    DOI: 10.1021/ma2004986

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  • Affine deformation of single polymer chain in poly(methyl methacrylate) films under uniaxial extension observed by scanning near-field optical microscopy

    Toru Ube, Hiroyuki Aoki, Shinzaburo Ito, Jun-ichi Horinaka, Toshikazu Takigawa, Toshiro Masuda

    POLYMER   50 ( 13 )   3016 - 3021   2009年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCI LTD  

    The conformation of single poly(methyl methacrylate) chain in the uniaxially stretched film was observed by the combination of the fluorescence labeling technique and scanning near-field optical microscopy (SNOM). The dimension of the individual probe chain (M-w = 1.99 x 10(6)) along the extension axis was evaluated from SNOM image. In the high molecular weight matrix (M-w = 1.89 x 10(6)) the average extension ratio at the single chain level coincided with the macroscopic extension ratio. The distribution of the chain conformation was in good agreement with that of the freely jointed chain followed by affine deformation. On the other hand, the probe chain embedded in the low molecular weight matrix (M-w = 1.76 x 10(5)) showed the smaller extension than that expected from the affine deformation. This suggests that the conformation of the probe chain is affected by the relaxation of the short surrounding chains through disentanglement. (C) 2009 Elsevier Ltd. All rights reserved.

    DOI: 10.1016/j.polymer.2009.04.057

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  • Conformation of single PMMA chain in uniaxially stretched film studied by scanning near-field optical microscopy

    Toru Ube, Hiroyuki Aoki, Shinzaburo Ito, Jun-ichi Horinaka, Toshikazu Takigawa

    POLYMER   48 ( 21 )   6221 - 6225   2007年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCI LTD  

    The conformation of the single polymer chain in uniaxially stretched poly(methyl methacrylate) (PMMA) films was studied by scanning near-field optical microscopy (SNOM), which enabled us to observe the elongated conformation of each polymer chain embedded in the film. The conformation of the individual PMMA chains was quantitatively evaluated from the fluorescence intensity distribution. Observation of films with different strains showed that the microscopic strain of the single chain was smaller than the macroscopic strain (6) of the film. Especially at the later stage of the deformation (epsilon > 1.5), the PMMA chain was not stretched with the increase in the macroscopic elongation of the film, suggesting the presence of slipping of polymer chain on the course of stretching. (c) 2007 Elsevier Ltd. All rights reserved.

    DOI: 10.1016/j.polymer.2007.08.039

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  • Development of novel network structures in crosslinked liquid-crystalline polymers

    Toru Ube

    POLYMER JOURNAL   51 ( 10 )   983 - 988   2019年10月

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    記述言語:英語   出版者・発行元:NATURE PUBLISHING GROUP  

    Crosslinked liquid-crystalline polymers (CLCPs) show macroscopic deformation along with a change in molecular order, which is triggered by various stimuli such as heat, electricity, and light. CLCPs containing photochromic moieties are realizable as photoresponsive soft actuators. This review focuses on recent developments in novel network structures of CLCPs: rearrangeable networks and interpenetrating polymer networks (IPNs). CLCPs with dynamic covalent bonds could be reshaped into 3D architectures through the rearrangement of the network topology, in contrast with conventional crosslinked polymers memorizing permanent shapes. The reshaped samples showed various photoinduced motions depending on their initial shapes. Furthermore, amorphous polymers were incorporated into conventional CLCP networks to control mechanical and photoresponsive properties. The sequential formation of CLCP and amorphous polymer networks resulted in IPN films with a homogeneous alignment of mesogens. The elastic moduli of IPN films were controlled through the selection of amorphous components. The incorporation of soft components such as poly(dodecyl methacrylate) and poly(dimethylsiloxane) (PDMS) significantly enhanced the rate of photoinduced bending. These strategies of controlling the network structures of CLCPs could enable the versatile design of photomobile polymer materials as soft actuators with desired architectures and functions.

    DOI: 10.1038/s41428-019-0224-1

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  • Fabrication of photomobile polymer materials with phase-separated structure of crosslinked azobenzene liquid-crystalline polymer and poly(dimethylsiloxane)

    Toru Ube, Takuya Yoda, Tomiki Ikeda

    LIQUID CRYSTALS   45 ( 13-15 )   2269 - 2273   2018年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:TAYLOR & FRANCIS LTD  

    Composite systems of liquid crystals (LCs) and polymers have been extensively studied in various forms such as polymer-dispersed LCs and polymer-stabilised LCs. Blending LCs and polymers is an effective approach to design functional materials with stimuli responsiveness and durability. Here, we show the development of a novel composite material with crosslinked azobenzene LC polymer (PAzo) and poly (dimethylsiloxane) (PDMS) aiming at the improvement of photomobile polymer materials in mechanical properties. The composite films were prepared by photopolymerisation of azobenzene monomers in PDMS elastomers. By forming phase separated structure, in which PAzo chains were dispersed in PDMS matrix, fracture strain of photomobile polymer materials was significantly enhanced. The composite film showed macroscopic bending upon irradiation with UV light. This result implies that PAzo domains in polymer matrix can work as microactuators to afford macroscopic deformation of the whole film. The further improvement of this system in photomechanical properties would be feasible through adequate control of composition and the alignment of mesogens.[GRAPHICS].

    DOI: 10.1080/02678292.2018.1516822

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  • Supramolecular assemblies composed of polymer brushes and conjugated molecules for organic photovoltaics

    Romu Nakayama, Toru Ube, Kenji Katayama, Masa-aki Haga, Tomiki Ikeda

    MOLECULAR CRYSTALS AND LIQUID CRYSTALS   676 ( 1 )   24 - 29   2018年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:TAYLOR & FRANCIS LTD  

    Poly(4-vinylpyridine) (P4VP) brushes were grafted onto a substrate via Cu(0)-mediated atom transfer radical polymerization and 1-pyrenebutyric acid (PBA) was incorporated into the brushes through hydrogen bonding interactions with P4VP by immersing the resulting substrate in PBA solution. Fluorescence measurements performed on the substrate after immersion showed that PBA units formed excimers even after the substrate was rinsed with dichloromethane, which confirms the formation of hydrogen bonds between pyridyl groups in the P4VP brushes and carboxyl groups of PBAs.

    DOI: 10.1080/15421406.2019.1595484

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  • Photoinduced deformation and isomerization of azobenzene liquid-crystalline polymer films at cryogenic temperature

    Shunya Ogikubo, Gaku Hashimoto, Toru Ube, Masayuki Suda, Hiroshi Yamamoto, Tomiki Ikeda

    MOLECULAR CRYSTALS AND LIQUID CRYSTALS   676 ( 1 )   30 - 35   2018年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:TAYLOR & FRANCIS LTD  

    We prepared 2 types of crosslinked liquid-crystalline polymers (CLCPs) (polyacrylates) with the same side-chain length but a different position of an azobenzene moiety in the side chain. We evaluated photoinduced deformation behavior of the CLCP films and photoisomerization behavior of azobenzene in the films at cryogenic temperature. Azobenzene moieties in both CLCP films showed no trans-cis isomerization and neither film exhibited bending behavior upon irradiation with UV light in liquid nitrogen [77 K]. On the other hand, when the film included azobenzene with a long spacer and a short tail, cis-trans isomerization of azobenzene and photoinduced deformation were observed in liquid nitrogen.

    DOI: 10.1080/15421406.2019.1595490

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  • Remolding of Photoresponsive Polymer Materials by Means of Dynamic Covalent Bonds In a Main Chain

    Masaya Matsushita, Kyohei Kawasaki, Toru Ube, Tomiki Ikeda

    MOLECULAR CRYSTALS AND LIQUID CRYSTALS   676 ( 1 )   17 - 23   2018年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:TAYLOR & FRANCIS LTD  

    We prepared crosslinked azobenzene main-chain liquid-crystalline polymers (MCLCPs), in which the exchange of crosslinks can be brought about by transesterification reactions. The exchangeable crosslinks enable reshaping and self-healing of the MCLCPs upon heating. Furthermore, the stress generated by stretching the MCLCP film is completely relaxed at 180 degrees C through rearrangement of networks. The film after hot-drawing shows reversible bending behavior upon irradiation with UV and visible light.

    DOI: 10.1080/15421406.2019.1595482

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  • Liquid-crystalline elastomer photoactuator with photorearrangeable network structures

    Haruna Tsunoda, Kyohei Kawasaki, Toru Ube, Tomiki Ikeda

    MOLECULAR CRYSTALS AND LIQUID CRYSTALS   662 ( 1 )   61 - 67   2018年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:TAYLOR & FRANCIS LTD  

    Crosslinked liquid-crystalline polymers (CLCPs) containing azobenzene moieties show reversible macroscopic deformation upon irradiation with light. The deformation of CLCPs strongly depends on alignment of mesogens. Therefore, it is desirable that the alignment of mesogens in CLCPs can be freely controlled even after crosslinking. We successfully realigned the mesogens in CLCPs with the aid of dynamic covalent bonds to accomplish this challenge. In this study, we prepared CLCP films containing dynamic covalent bonds and photoalignable azobenzene moieties. Photoalignment of the films was performed by irradiation with linearly polarized UV light at 120 degrees C. The films after photoalignment showed bending behavior along the direction in which the mesogens had been realigned by photoalignment when irradiated with unpolarized UV light. This result indicates that alignment of mesogens in the films changes before and after photoalignment even after crosslinking.

    DOI: 10.1080/15421406.2018.1466242

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  • Two-photon actuation of crosslinked liquid-crystalline polymers utilizing energy transfer system

    Shota Sasaki, Toru Ube, Kenji Katayama, Masayasu Muramatsu, Hiroshi Miyasaka, Tomiki Ikeda

    MOLECULAR CRYSTALS AND LIQUID CRYSTALS   662 ( 1 )   53 - 60   2018年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:TAYLOR & FRANCIS LTD  

    We prepared crosslinked azotolane liquid-crystalline polymer (LCP) films doped with a stilbene derivative (two-photon chromophore) utilizing an interpenetrating polymer network (IPN) structure. The IPN films bend toward the light source upon irradiation with femtosecond laser pulses at 600nm, which can excite the stilbene derivative by two-photon absorption. The bending speed of the IPN films increases with the square of the laser pulse intensity, which is compelling evidence for the two-photon processes.

    DOI: 10.1080/15421406.2018.1466241

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  • Formation of ordered nanostructures in liquid-crystalline block copolymers with side-chain semiconductor materials

    Naoto Yanahashi, Toru Ube, Tomiki Ikeda

    MOLECULAR CRYSTALS AND LIQUID CRYSTALS   662 ( 1 )   68 - 74   2018年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:TAYLOR & FRANCIS LTD  

    We developed a novel block copolymer composed of poly(ethylene oxide) (PEO) and polymethacrylate functionalized with liquid-cryst-alline oligothiophene by using the atom transfer radical polymerization (ATRP), aiming at application to organic photovoltaic (OPV) cells. Thermal investigation showed that the resultant polymer exhibits liquid-crystalline phases both on heating and cooling. Morphologies of the thin films of the block copolymer were investigated by atomic force microscopy (AFM). Microphase separation with a small size of almost 10nm (nano-phase-separated structures) was observed upon annealing.

    DOI: 10.1080/15421406.2018.1466243

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  • Nano Structures of Thin Films of Block Copolymers with Oligothiophene Side Chains

    Masahiro Kaneko, Nana Takayanagi, Toru Ube, Masa-Aki Haga, Tomiki Ikeda

    MOLECULAR CRYSTALS AND LIQUID CRYSTALS   617 ( 1 )   58 - 66   2015年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:TAYLOR & FRANCIS LTD  

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  • Synthesis of Polythiophene with a Photo-Crosslinkable Side Chain

    Takahito Kosaka, Toru Ube, Masa-Aki Haga, Tomiki Ikeda

    MOLECULAR CRYSTALS AND LIQUID CRYSTALS   617 ( 1 )   67 - 72   2015年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:TAYLOR & FRANCIS LTD  

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  • Remoldable Crosslinked Liquid-Crystalline Polysiloxane with Side Chain Mesogens Based on Exchangeable Crosslinks

    Kyohei Kawasaki, Toru Ube, Tomiki Ikeda

    MOLECULAR CRYSTALS AND LIQUID CRYSTALS   614 ( 1 )   62 - 66   2015年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:TAYLOR & FRANCIS LTD  

    Crosslinked liquid-crystalline polymers (CLCPs) show unique behavior of deforming macroscopically when stimulated with heat, electricity and light. However, they cannot be remolded and reshaped once prepared. Here, we designed crosslinked polysiloxane with side chain mesogens that contain exchangeable crosslinking points based on transesterification between phenyl benzoates and hydroxy groups. After the formation of a polymer network, a base catalyst was introduced into the CLCP. When heated at 80 degrees C, a piece of the CLCP was reshaped into a film and separate pieces of the CLCP were fused together, indicating that the CLCP is remoldable.

    DOI: 10.1080/15421406.2015.1049910

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  • Photomobile Polymer Materials with Double Network Structures: Crosslinked Azobenzene Liquid-Crystalline Polymer/Methacrylate Composites

    Kiyohide Takado, Toru Ube, Tomiki Ikeda

    MOLECULAR CRYSTALS AND LIQUID CRYSTALS   601 ( 1 )   43 - 48   2014年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:TAYLOR & FRANCIS LTD  

    We prepared photomobile polymer materials composed of crosslinked azobenzene liquid-crystalline polymers (LCPs) and methacrylates with interpenetrating polymer network (IPN) structures, and explored their photoresponsive behavior. The IPN films exhibited reversible bending upon photoirradiation. In addition, the durability of the IPN films was much higher than that of the pristine crosslinked azobenzene LCP films.

    DOI: 10.1080/15421406.2014.940491

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  • MATERIALS SCIENCE A superelastic organic crystal

    Tomiki Ikeda, Toru Ube

    NATURE   511 ( 7509 )   300 - 301   2014年7月

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    記述言語:英語   出版者・発行元:NATURE PUBLISHING GROUP  

    DOI: 10.1038/511300a

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  • Photomobile Properties of Interpenetrating Polymer Network Films Composed of Azobenzene Liquid Crystalline Polymer and Polymethacrylates

    Toru Ube, Kiyohide Takado, Tomiki Ikeda

    MOLECULAR CRYSTALS AND LIQUID CRYSTALS   594 ( 1 )   86 - 91   2014年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:TAYLOR & FRANCIS LTD  

    Various fabrication methods of photomobile polymer materials containing photochromic moieties have been developed to improve their photoresponsive and mechanical properties. Here, we newly prepared photomobile polymer materials with interpenetrating polymer network (IPN) structures. The IPN films, which are composed of azobenzene liquid crystalline polymer (LCP) and polymethacrylates, showed reversible bending behavior upon exposure to UV and visible light. Bending speed of the IPN films became higher with decreasing glass-transition temperature of polymethacrylate components. The IPN film containing poly(dodecyl methacrylate) showed faster bending than the pristine azobenzene LCP film.

    DOI: 10.1080/15421406.2014.917479

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  • Function of liquid crystals 招待 査読

    Junichi Hanna, Tomiki Ikeda, Toru Ube, Masanori Ozaki, Takashi Kato, Masafumi Yoshio, Atsushi Yoshizawa

    The Liquid Crystal Display Story: 50 Years of Liquid Crystal R and D that Lead the Way to the Future   357 - 410   2014年1月

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    記述言語:英語   掲載種別:論文集(書籍)内論文   出版者・発行元:Springer Japan  

    An organic semiconductor is material that is capable of transporting a charge, that is, electrons and holes. By this characteristic, that is, the property to support a current flow, they can be used in various electronic devices. In the early 1970s, organic semiconductors have been put to their first practical use in the photosensitive drum of copy machines. Thereafter, it began to be used as a practical material for organic electroluminescent (EL) elements in the 1990s. In recent years, research and development has been actively aimed to practical use in organic solar cells and organic transistors.

    DOI: 10.1007/978-4-431-54859-1_11

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  • Molecular dynamics in azobenzene liquid crystal polymer films measured by time-resolved techniques

    T. Fujii, S. Kuwahara, K. Katayama, K. Takado, T. Ube, T. Ikeda

    PHYSICAL CHEMISTRY CHEMICAL PHYSICS   16 ( 22 )   10485 - 10490   2014年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ROYAL SOC CHEMISTRY  

    Photo-induced molecular motion in a liquid crystal polymer film including azobenzene was studied by the heterodyne transient grating method. The film was confined in a liquid crystal cell, where it is a photomobile film under free-standing conditions. By observation of the refractive index change induced by a laser pulse, contraction of the film was observed on the order of several hundreds of nanoseconds, and the subsequent reorientation and molecular rotation dynamics were observed from a few microseconds to a hundred milliseconds. Finally, the cis isomer of azobenzene was thermally returned back to the trans isomer in about ten seconds because the film could not be bent in the liquid crystal cell. Since the contraction, reorientation and molecular rotation took place before the cis to trans back-transformation, these processes correspond to the preliminary molecular motion preceding the macroscopic bending of the film.

    DOI: 10.1039/c4cp00457d

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  • Conformation of Single Polymer Chain in Rubbed Thin Film Observed by Fluorescence Imaging

    Toru Ube, Akihiko Shin, Hiroyuki Aoki, Shinzaburo Ito

    LANGMUIR   28 ( 39 )   13871 - 13876   2012年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER CHEMICAL SOC  

    The conformation of poly(methyl methacrylate) (PMMA) chains in a thin film after the rubbing process was investigated through the direct observation of the single chains by scanning near-field optical microscopy (SNOM) and excitation polarization modulation microscopy (EPMM). The rubbing at room temperature hardly changed the dimension on the whole chain scale in spite of the increase in orientational order on the segmental scale. The increase in the chain dimension along the rubbing direction was observed in the film rubbed at the higher temperature, which showed a surface morphology with fine groove. The extension ratio of the whole chain in the rubbed film was much smaller than that in the uniaxially stretched film. This indicates that the rubbing process mainly induces the conformational change on the length scale of the monomer unit rather than for the whole chain.

    DOI: 10.1021/la302513c

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  • Relaxation of single polymer chain in binary molecular weight blends observed by scanning near-field optical microscopy

    Toru Ube, Hiroyuki Aoki, Shinzaburo Ito, Jun-ichi Horinaka, Toshikazu Takigawa

    SOFT MATTER   8 ( 20 )   5603 - 5611   2012年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ROYAL SOC CHEMISTRY  

    The conformational relaxation of single polymer chains in uniaxially elongated poly(methyl methacrylate) (PMMA) films were examined by direct observation using scanning near-field optical microscopy (SNOM) and excitation polarization modulation microscopy (EPMM). The relaxation behavior of the individual PMMA chains was investigated in the binary blend systems consisting of high and low molecular weight components. The whole chain dimension and the segmental orientation were evaluated for high molecular weight long chains from SNOM and EPMM images, respectively. At the early stage of the stress relaxation process, not only the segmental orientation but also the whole chain dimension of the long chain decreased faster in matrices with short chains. This indicates that the relaxation at the whole chain scale is accelerated by disentanglement, which is caused by the motion of the short surrounding chains. The fast relaxation in the whole chain dimension cannot be explained by the constraint release picture in the theoretical models, which assumes that the disentanglement only activates the local motion of the long chain.

    DOI: 10.1039/c2sm25272d

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  • Characterization of surface compositions of phase-separated structures in conjugated poly(phenylene vinylene) blends by scanning near-field optical microscopy

    Li-Ting Lee, Toru Ube, Hiroyuki Aoki, Shinzaburo Ito

    POLYMER   52 ( 25 )   5897 - 5903   2011年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCI LTD  

    The phase-separated structures in a thin-film conjugated polymer blend, poly(2-methoxy-5-(3,7-dimethyloctyloxy)-1,4-phenylenevinylene)/poly(methyl methacrylate) (MDMO-PPV/PMMA) was studied by scanning near-field optical microscopy (SNOM), which can probe both of the surface topography and the chemical composition at high spatial resolution. In thin films of MDMO-PPV/PMMA, the PMMA-rich phase with less fluorescent emission appeared as a raised structure while the MDMO-PPV-rich phase with highly fluorescent emission was present as a collapsed phase with a low height. Such the vertical structure of the phase separation was dependent on the solvent quality for each component. On the other hand, the lateral structure was determined by the surface property of the substrate. As the degree of hydrophobic character of the substrate increased, the PMMA domains tended to form a continuous form to a separated spherical form. This evolution arise from a change in affinity between the substrate surface and PMMA, which the hydrophilic substrate has higher affinity to PMMA for maintaining the continuous structures and the hydrophobic substrate with lower affinity to PMMA can not hold the structures continuously. (C) 2011 Elsevier Ltd. All rights reserved.

    DOI: 10.1016/j.polymer.2011.10.043

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  • Photomobile polymer materials: from nano to macro

    Tomiki Ikeda, Toru Ube

    MATERIALS TODAY   14 ( 10 )   480 - 487   2011年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCI LTD  

    Modern society is based on the production of energy, primarily, from fossil fuels; however, these resources are limited. Therefore we are now confronted with a difficult problem: producing energy without burning fossil fuels. Many countries have utilized nuclear power to generate electricity as an effective source of energy, such as the US, France, and Japan. However, the tragic disaster at the Fukushima nuclear power station has reminded us that nuclear power is a double-edged sword: it may be a useful energy source, but it can bare its fangs when we lose control. We have many natural energy sources that are present in unlimited quantities, and so are unlikely to be exhausted easily: namely, sunlight, water, and wind. It is thus timely to consider further developing these natural resources to replace nuclear power for the production of energy.

    DOI: 10.1016/S1369-7021(11)70212-7

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書籍等出版物

  • スマートウィンドウ(調光窓)の開発動向

    ( 担当: 分担執筆 範囲: 第3章 3 太陽光自律応答型スマートウィンドウ)

    シーエムシー出版  2023年8月  ( ISBN:9784781317465

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    総ページ数:208   担当ページ:pp. 108-113  

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  • Mechanically responsive materials for soft robotics

    ( 担当: 分担執筆 範囲: Cross-Linked Liquid-Crystalline Polymers as Photomobile Materials)

    Wiley-VCH  2020年  ( ISBN:9783527346202

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    総ページ数:xiv, 427 p.   担当ページ:pp. 209-232   記述言語:英語  

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  • Photosynergetic Responses in Molecules and Molecular Aggregates

    ( 担当: 分担執筆 範囲: Photomechanical Effects in Crosslinked Liquid-Crystalline Polymers with Photosynergetic Processes)

    Springer  2020年  ( ISBN:9789811554513

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    担当ページ:pp. 479–492  

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  • 光機能性有機・高分子材料における新たな息吹

    ( 担当: 分担執筆 範囲: 光応答性液晶高分子アクチュエーター)

    シーエムシー出版  2019年4月  ( ISBN:9784781314143

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    総ページ数:ix, 333p   担当ページ:pp. 69-76   記述言語:日本語  

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  • Photomechanical Materials, Composites, and Systems: Wireless Transduction of Light into Work

    ( 担当: 分担執筆 範囲: A Historical Overview of Photomechanical Effects in Materials, Composites, and Systems)

    Wiley  2017年7月  ( ISBN:9781119123309

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    総ページ数:432   担当ページ:pp. 1-35  

    ASIN

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  • 化学便覧 応用化学編 第7版

    ( 担当: 分担執筆 範囲: 高分子液晶)

    丸善出版  2014年1月  ( ISBN:9784621087596

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    総ページ数:2冊   担当ページ:pp. 1244-1245   記述言語:日本語  

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  • 液晶ディスプレイ物語 : 50年の液晶開発と未来に託す夢

    ( 担当: 分担執筆 範囲: 光運動材料:ナノからマクロへ)

    エース出版  2013年3月  ( ISBN:9784901175227

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    総ページ数:xi, 517p   担当ページ:pp. 456-467   記述言語:日本語  

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▼全件表示

MISC

  • 光応答高分子アクチュエータ

    宇部 達, 池田 富樹

    化学工業   69 ( 6 )   397 - 402   2018年6月

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    担当区分:筆頭著者   掲載種別:記事・総説・解説・論説等(商業誌、新聞、ウェブメディア)  

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  • 架橋液晶高分子材料におけるネットワーク構造制御手法の開拓

    宇部 達

    液晶   22 ( 1 )   54 - 59   2018年1月

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    担当区分:筆頭著者   掲載種別:記事・総説・解説・論説等(学術雑誌)  

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  • フォトメカニカル機能を有する架橋液晶高分子の構造制御

    宇部 達

    液晶   21 ( 4 )   355 - 357   2017年10月

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    担当区分:筆頭著者   掲載種別:記事・総説・解説・論説等(学術雑誌)  

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  • 光で動くプラスチック —高分子光運動材料の最前線

    宇部 達, 池田 富樹

    化学   70 ( 3 )   66 - 67   2015年3月

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    担当区分:筆頭著者   掲載種別:記事・総説・解説・論説等(商業誌、新聞、ウェブメディア)  

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  • 高分子光運動材料: ナノからマクロへ

    池田 富樹, 宇部 達

    光学   41 ( 2 )   71 - 77   2012年2月

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    掲載種別:記事・総説・解説・論説等(学術雑誌)  

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講演・口頭発表等

  • Control of Three-Dimensional Motions in Crosslinked Liquid-Crystalline Polymer Materials 招待

    Toru Ube

    1st Glowing Polymer Symposium in KANTO (GPS-K2018)  2018年12月 

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    会議種別:口頭発表(招待・特別)  

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  • 架橋液晶高分子を基盤とした光運動材料の開発 招待

    宇部 達

    日本化学会第98春季年会  2018年3月 

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    会議種別:口頭発表(招待・特別)  

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  • 光応答液晶高分子アクチュエータ 招待

    宇部 達

    日本化学会第98春季年会  2018年3月 

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    会議種別:口頭発表(招待・特別)  

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  • 架橋液晶高分子材料におけるネットワーク構造制御手法の開拓 招待

    宇部 達

    2017年日本液晶学会討論会  2017年9月 

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    会議種別:口頭発表(招待・特別)  

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  • 高分子光運動材料の創製 招待

    宇部 達

    第66回高分子学会年次大会  2017年5月 

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    会議種別:口頭発表(招待・特別)  

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受賞

  • 高分子研究奨励賞

    2018年5月   高分子学会   架橋液晶高分子における新規ネットワーク構造の開拓

    宇部 達

  • 日本液晶学会奨励賞

    2017年9月   日本液晶学会   架橋液晶高分子材料におけるネットワーク構造制御手法の開拓

    宇部 達

  • 日本化学会第96春季年会優秀講演賞(学術)

    2016年5月   日本化学会   動的共有結合をもつ液晶エラストマーの光運動特性制御

    宇部 達

共同研究・競争的資金等の研究課題

  • 高分子光運動材料の液体窒素中における光変形メカニズムの探究

    研究課題/領域番号:21K05171  2021年4月 - 2024年3月

    日本学術振興会  科学研究費助成事業 基盤研究(C)  基盤研究(C)  中央大学

    宇部 達

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    担当区分:研究代表者 

    配分額:4160000円 ( 直接経費:3200000円 、 間接経費:960000円 )

    架橋液晶高分子にアゾベンゼンなどのフォトクロミック色素を導入すると,光照射によるフィルムの変形が可能になる。この高分子光運動材料は,電源や配線が不要なソフトアクチュエーターとしての応用が期待されている。これまでの研究において,光変形が液体窒素中においても誘起されることが明らかになっている。本研究は,フォトクロミック液晶高分子における分子レベルの構造とマクロな光応答性との相関を攻究し,極低温における変形メカニズムを解明することを目的している。
    本年度は,液晶高分子における配向相関制御と光変形の温度依存性について探究した。アゾベンゼン/ビシクロヘキシル系およびアゾベンゼン/フェニルシクロヘキシル系について,重合基およびスペーサー長を様々に変化させてフィルムを作製した。高分子フィルムの液晶性は側鎖スペーサー長に依存し,スペーサーをもたない場合は液晶性を示さなかった。液体窒素中における変形挙動を評価したところ,スペーサーをもたないフィルムはシス-トランス異性化に伴う変形を示したのに対し,スペーサーを有するフィルムでは変形が僅かであった。これは,液晶相よりも等方相の方がアゾベンゼン部位周囲の自由体積が大きいためであると考えている。室温においては,液晶相を示すフィルムの方が光相転移に伴う大きな変形を示すが,液体窒素中においては自由体積が重要な要因であることが示唆された。
    また,アゾベンゼンを主鎖に有する液晶高分子および非晶高分子を新たに合成した。いずれのフィルムも延伸処理によりアゾベンゼンを配向させることが可能であり,室温において紫外光・可視光を照射すると可逆的に屈曲した。これらのフィルムについても屈曲挙動の温度依存性を評価し,フォトクロミック分子導入部位と変形挙動の相関を明らかにする予定である。

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  • 架橋液晶高分子/非晶高分子複合系のミクロ構造の探究と光アクチュエーターへの展開

    研究課題/領域番号:18K14286  2018年4月 - 2021年3月

    日本学術振興会  科学研究費助成事業 若手研究  若手研究  中央大学

    宇部 達

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    担当区分:研究代表者 

    配分額:4030000円 ( 直接経費:3100000円 、 間接経費:930000円 )

    架橋液晶高分子/非晶高分子複合系におけるモルフォロジーとマクロな物性・機能を探究し,ミクロ構造制御による高分子光運動材料の高性能・高機能化を図った。架橋アゾベンゼン液晶高分子と非晶高分子から成る相互侵入高分子網目(IPN)にスメクチック構造を導入することにより,紫外光・可視光照射時の光屈曲特性が向上することが分かった。またIPNにおける非晶高分子を非架橋とすることにより成形加工性が改善され,3次元形状への成形が可能になった。さらに,複合系における相分離構造制御により力学特性に優れた光運動材料を創出した。

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  • 液晶性ポリマーブラシを用いた有機半導体のナノ構造制御

    研究課題/領域番号:15K13712  2015年4月 - 2017年3月

    日本学術振興会  科学研究費助成事業  挑戦的萌芽研究  中央大学

    池田 富樹, 宇部 達

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    配分額:3900000円 ( 直接経費:3000000円 、 間接経費:900000円 )

    有機デバイスにおけるナノ構造制御を目指し,側鎖に液晶性有機半導体を含有するポリマーブラシを作製した。表面開始原子移動ラジカル重合(SI-ATRP)法によりポリマーブラシを作製したところ,メタクリレート部位を有するペリレンジイミド(PDI)モノマーが良好な重合性を示した。PDIポリマーブラシのAFM測定から,PDIが数十ナノメータースケールのドメインを形成することが分かった。さらにPDIポリマーブラシに電子ドナー材料をスピンコートすることにより,PDIポリマーブラシをテンプレートとしてドナーとアクセプターのヘテロ構造を形成できることが明らかになった。

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  • 架橋液晶高分子と非晶高分子の複合化による光エネルギー変換材料の新展開

    研究課題/領域番号:26870592  2014年4月 - 2016年3月

    日本学術振興会  科学研究費助成事業 若手研究(B)  若手研究(B)  中央大学

    宇部 達

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    担当区分:研究代表者 

    配分額:3640000円 ( 直接経費:2800000円 、 間接経費:840000円 )

    架橋フォトクロミック液晶高分子は,光照射によりマクロな変形を引き起こすことができる新規材料として注目されている.本研究では,相互侵入高分子網目(IPN)構造を形成することにより架橋アゾベンゼン液晶高分子と非晶高分子を複合化した.さまざまなガラス転移温度の非晶成分を導入することにより,フィルムの光屈曲特性や力学的強度を向上させることが可能になった.光応答性や力学特性を詳細に評価したところ,IPN化により非晶成分の性質が付与されるのみならず液晶成分の運動性も変化することが明らかになった.

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  • 単一高分子鎖の分子配向・分子鎖形態の近接場顕微分光法による研究

    研究課題/領域番号:10J04121  2010年 - 2011年

    日本学術振興会  科学研究費助成事業 特別研究員奨励費  特別研究員奨励費  京都大学

    宇部 達

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    担当区分:研究代表者 

    配分額:1400000円 ( 直接経費:1400000円 )

    本研究では、高分子材料に外力を与えたときの高分子鎖の配向や緩和挙動を解明することを目的とし、走査型近接場光学顕微鏡(SNOM)を用いて単一高分子鎖の直接観察を行った。蛍光ラベルを施した高分子鎖を微少量含む試料を測定することで、バルクおよび薄膜中の分子鎖形態を評価した。
    1.高分子量成分と低分子量成分の二元ブレンドバルク系について、一軸伸長後の応力緩和過程における単一高分子鎖をSNOMにより直接観察した。低分子量成分を多く含む試料においては、周りの分子鎖との絡み合いの解消が起こることにより、短時間領域で高分子量成分の分子鎖全体としての緩和が速くなることが分かった。従来の理論モデルでは、絡み合いの解消は局所的な緩和のみを促進するとされているが、SNOMによる観察結果は、絡み合いの解消により分子鎖全体としての大規模な運動が促進されることを示唆している。
    2.ガラス転移温度以下における高分子薄膜の表面ラビング処理による、分子鎖の配向・形態の変化について検討した。まず、励起偏光変調顕微鏡により、ラベル鎖中の色素の配向を評価したところ、ラビング後の膜ではモノマー単位スケールでの配向度が増大していることが分かった。一方、SNOMにより分子鎖形態を観察したところ、分子鎖の広がりはラビングによりほとんど変化しなかった。これらのことから、ラビング過程では分子鎖全体としての形態変化は起こりにくく、主にモノマー単位スケールでの局所配向が誘起されることが明らかになった。
    以上のように、これまでは困難であった直接観察を行うことにより、絡み合い系における分子鎖の挙動を単一高分子鎖という基礎から詳細に議論することができた。単一高分子鎖の構造やダイナミクスを原点とした科学は、測定手法の開発により将来的にさらに発達すると予測され、本研究はその基盤となると考えられる。

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担当経験のある科目(授業)

  • 機能性高分子化学特論

    2020年4月 - 現在   機関名:中央大学

  • 高分子化学

    2020年4月 - 現在   機関名:中央大学

  • 化学実験

    2011年4月 - 2020年3月   機関名:中央大学

委員歴

  • 2022年8月 - 現在

    日本液晶学会   代議員  

  • 2022年4月 - 現在

    高分子学会   超分子研究会運営委員  

  • 2018年9月 - 現在

    日本液晶学会   液晶化学・材料研究フォーラム委員