研究者詳細 - 竹岡　敬和

Hydrophobic and hydrophilic polyrotaxane based movable cross-linkers for thermo-sensitive poly(N-isopropylacrylamide) gels

Imran Abu Bin, Seki Takahiro, Ito Kohzo, Takeoka Yukikazu

Transactions of the Materials Research Society of Japan 35 巻 ( 2 ) 頁： 291-297 - 297 2010年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：The Materials Research Society of Japan

A novel hydrogel has been fabricated using vinyl modified polyrotaxane as a cross-linker. A sparsely dispersed propylene oxide modified α-cyclodextrins which were threaded into the long polyethylene glycol (Mw = 35000) and were trapped by bulky 1-adamantanamine molecules was used as a hydrophilic polyrotaxane, HPR. HPR was modified by a small amount 2-acryloyloxyethylisocyanate monomer to obtain a water soluble polyrotaxane-based movable cross-linker, MHPR. Polymer gels, prepared by free radical polymerization of thermo-sensitive monomer N-isopropylacrylamide (NIPA) in presence of MHPR cross-linker, gave transparent, soft and flexible, mechanically strong and fast thermo-sensitive gels. The gel changes its volume isotropically and reaches rapidly to the equilibrium shrunken state after a temperature jump. The hydrophilicity of the cross-linker retains the homogeneity in the gel network and restricts the formation of aggregated globules, which permits the poly(NIPA) chains along with macrocycles to move or rotate freely inside the gel networks under deformation. The movability of the cross-links can strongly minimize their localized stress during deformation. The fascinating

DOI： 10.14723/tmrsj.35.291

Facile synthesis of sliding poly(NIPA) gels using a vinyl modified polyrotaxane as a cross-linker

Bin Imran Abu, Seki Takahiro, Ito Kohzo, Takeoka Yukikazu

Transactions of the Materials Research Society of Japan 35 巻 ( 4 ) 頁： 841-844 - 844 2010年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：The Materials Research Society of Japan

A unique hydrogel has been synthesized using supramolecular polyrotaxane as the starting material. Sparsely dispersed α-cyclodextrins threaded into long polyethylene glycol axle (Mw=35000) trapped with a stable capping agent, 1-adamantanamine of polyrotaxane (PR) unit was used for this purpose. The modification of the hydroxyl groups of α-CDs of the PR by a vinyl monomer containing an active isocyanate group at one end resulted in the formation of a stable carbamate bond with hydroxyl groups to give the modified polyrotaxane based cross-linker (MPR). Polymer gels were designed using MPR as a cross-linker and N-isopropylacrylamide, NIPA as a monomer and transparent, very soft, flexible, fast responsive and mechanically improved polymer gels could be obtained. The polymer chains can slide and rotate about the movable cross-linker in the gel network, which potentially improves the properties of the gels over conventional chemically cross-linked polymer gel.

DOI： 10.14723/tmrsj.35.841

Characteristics of disperse poly(N-isopropylacrylamide) brushes on silicon surfaces by Atom transfer radical polymerization

Huda, M.N, Seki, T, Suzuki, H, Kabir, A.N.M.H, Rashid, H.U, Takeoka, Y

Transactions of the Materials Research Society Japan in press. 巻 2010年

Hydrophobic and hydrophilic polyrotaxane based movable cross-linkers for thermo-sensitive poly(N-isopropylacrylamide) gels 査読有り

Imran, A. B, Seki, T, Ito, K, Takeoka, Y

Transactions of the Materials Research Society Japan in press. 巻 2010年

Facile synthesis of sliding poly(NIPA) gels using a vinyl modified polyrotaxane as a Cross-linker 査読有り

Imran, A. B, Seki, T, Ito, K, Takeoka, Y

Transactions of the Materials Research Society Japan in press. 巻 2010年

Confined Stimuli-Responsive Polymer Gel in Inverse Opal Polymer Membrane for Colorimetric Glucose Sensor 査読有り

Honda, M; Kataoka, K; Seki, T; Takeoka, Y

LANGMUIR 25 巻 ( 14 ) 頁： 8349 - 8356 2009年7月

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

Wedeveloped a totally synthetic colorimetric glucose-sensing system that is composed of glucose-responsive hydrogel particles confined in an inverse opal polymer membrane. This system exhibits structural color on the basis of Bragg diffraction arising from the 3-D ordered structure with periodicity on the order of the wavelength of visible light. The volume of the hydrogel particles reversibly changes as the glucose concentration varies in the separated pores of the inverse opal polymer membrane; this system reveals a reversible change in the color appearance and the peak intensity of the reflection spectra with the variation in the glucose concentration. By careful design of the system, we can detect the important range of glucose concentration around the threshold value for diagnosing diabetes mellitus by using the colorimetric glucose-sensing system. © 2009 American Chemical Society.

DOI： 10.1021/la804262b

PubMed

Dual Tuning of the Photonic Band-Gap Structure in Soft Photonic Crystals 査読有り国際誌

Honda, M; Seki, T; Takeoka, Y

ADVANCED MATERIALS 21 巻 ( 18 ) 頁： 1801 - + 2009年5月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Advanced Materials

The dual tuning of the photonic band-gap structure in soft photonic crystals were studied using thermosensitive gel particles confined in a pH sensitive inverse-opal gel. The study demonstrated tunable photonic crystals composed of unconnected colloidal silica particles in a matrix consisting of a crosslinked redox-active polymer. The dually photonic crystal (DTPC) composed of thermosensitive gel particles confined in a pH-sensitive inverse opal gel is found to consist of a regular arrangement of interconnecting spherical voids. The crystals were prepared using a CCC, which was further fabricated on a clean glass slide by a solvent evaporation method. The position of the photonic band-gap is exhibited to be thermally regulated, while the intensity of the photonic band-gap is affected by the pH, and is independent of the extensive switching. The formulated DTPC is resulted to possess potential for use as a display medium, which can be controlled by external stimuli.

DOI： 10.1002/adma.200801258

Structural Colored Liquid Membrane without Angle Dependence 査読有り国際誌

Takeoka, Y; Honda, M; Seki, T; Ishii, M; Nakamura, H

ACS APPLIED MATERIALS & INTERFACES 1 巻 ( 5 ) 頁： 982 - 986 2009年5月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ACS Applied Materials and Interfaces

We have demonstrated for the first time that condensed gel particle suspensions in amorphous-like states display structural color with low angle dependence. This finding is in contrast to the common understanding that a periodic dielectric structure is fundamental to photonic band gap (PBG) production, and it validates the theory that a tight bonding model that is applicable to semiconductor systems can also be applied to photonic systems. More practically, this structural colored suspension represents a promising new material for the manufacture of reflective full-color displays with a wide viewing angle and nonfading color materials. This liquid system shows promise as a display material because electronic equipment used for display systems can easily be filled with the liquid in the same way that liquid crystals are currently used. © 2009 American Chemical Society.

DOI： 10.1021/am900074v

コロイド微粒子が形成する集合状態と構造発色性材料への応用(<特集>複合高分子により形成される疑似結晶構造の最前線)

PubMed

Structural Colored Gels for Tunable Soft Photonic Crystals 招待有り査読有り

Rashid, H.-u., Seki, T., Takeoka, Y.

The Chemical Record 9 巻頁： 87-105 2009年

Structural Colored Gel 招待有り査読有り

Takeoka, Y.

J. Photopolymer Sci. & Tech. 22 巻頁： 123 - 132 2009年

Electrochromism based on structural clour changes in a polyelectrolyte gel 査読有り

Ueno, K., Sakamoto, J., Takeoka, Y. Watanabe, M.

J. Mater. Chem. 1 巻頁： 4778-4783 2009年

Structural Coloured Liquid Membrane without Angle-Dependence 査読有り

Takeoka, Y. Honda, M., Seki, T., Ishii, M., Nakamura, H.

ACS Applied Materials & Interfaces 1 巻頁： 982-986 2009年

Template Synthesis for Stimuli-Responsive Angle Independent Structural ColoredSmart Materials 査読有り

Harun-Ur-Rashid, M., Imran, A. B., Seki, T., Ishii, M., Nakamura, H., Takeoka, Y.

Transactions of the Materials Research Society Japan in press 巻 2009年

Confined Stimuli-Responsive Polymer Gel in Inverse Opal Polymer Membrane for Colorimetric Glucose sensor 査読有り

Honda, M., Kataoka, K., Seki, T., Takeoka, Y.

Langmuir 25 巻頁： 8349-8356 2009年

*Dual Tuning of Photonic Band Gap Structure in Soft Photonic Crystal 査読有り

Honda, M., Seki, T., Takeoka, Y.

Adv. Mater. 21 巻頁： 1801-1804 2009年

竹岡敬和

日本結晶成長学会誌 36 巻 ( 1 ) 頁： 49-54 - 54 2009年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：日本結晶成長学会

本稿では,最近筆者が興味を持っているコロイド粒子集合体とその光学特性について,主に構造発色性材料としての観点から紹介する.特に,最後に説明するコロイド準結晶は,ごく最近,その存在が明らかになったばかりであり,構造発色性材料としての性質を示す系はまだ見つかってはいない.筆者も最近取り組み始めた研究であり,今後の展開が楽しみな対象である.

DOI： 10.19009/jjacg.36.1_49

CiNii Books

Electrochromism based on structural colour changes in a polyelectrolyte gel 査読有り国際誌

Ueno, K; Sakamoto, J; Takeoka, Y; Watanabe, M

JOURNAL OF MATERIALS CHEMISTRY 19 巻 ( 27 ) 頁： 4778 - 4783 2009年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Materials Chemistry

Electrochromism based on structural colours was demonstrated by employing a simple system composed of a two-electrode cell, a salt-free organic solvent, and a nanostructured electroactive soft material. A polyelectrolyte gel, poly(HEMA-co-MAPTA-PF6), with an inverse-opal structure was prepared by using a polystyrene close-packed colloidal crystal as a template. The resulting gel swollen in binary organic solvents exhibited monochromatic structural colours. The structural colour of the gel was altered over the entire visible light region by changing the solvent polarity. Moreover, the structural colour could be tuned by applying a relatively low voltage, where the change in the lattice constant of the inverse-opal along the gel thickness direction, triggered by an electrodragging force on the polyelectrolyte gel under the electric field, was responsible for the colour change. The present system offers a novel concept for full-colour electrochromic materials, and the system can be tuned to exhibit the full range of colours by using single materials. © 2009 The Royal Society of Chemistry.

DOI： 10.1039/b900261h