Faculty Profiles - TAKEOKA, Yukikazu

Papers - TAKEOKA, Yukikazu

Division display 201 - 220 of about 251 ／ All the affair displays >>

高分子科学最近の進歩構造色ゲル

竹岡敬和

高分子 Vol. 54 ( 4 ) page： 258-263 - 263 2005

Surface activity and redox behavior of a non-ionic surfactant containing a phenothiazine group Reviewed

MABH Susan, A Ishibashi, Y Takeoka, M Watanabe

COLLOIDS AND SURFACES B-BIOINTERFACES Vol. 38 ( 3-4 ) page： 167 - 173 2004.11

Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER SCIENCE BV

A novel non-ionic surfactant, alpha-(phenothiazinylhexyl)-omega-hydroxy-oligo(ethylene oxide) (PCPEG) containing phenothiazine as an electroactive group has been synthesized. Fundamental interfacial behavior of the surfactant at the air/water interface has been investigated by means of surface tensiometry to provide an insight into the relationship between the structure of the hydrophobic moiety and the surfactant properties. A comparison of diffusivity of PCPEG in the aqueous phase with that in the acetonitrile solution at high PCPEG concentrations shows that micellization has a pronounced effect on the redox behavior of PCPEG. The electrochemical responses for PCPEG aqueous solutions at the interface of a glassy carbon electrode are fairly dependent on the concentration of PCPEG. Above CMC, PCPEG molecules self-associate to form micellar aggregates and the formation and disruption of micelles can be reversibly controlled by change in the redox state of the phenothiazine group. The cyclic voltammetric responses for PCPEG aqueous solutions have been correlated with the dissolved states to explain the distinctive feature of the surfactant. (C) 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.colsurfb.2004.01.016

Web of Science

PubMed

Structural Colored Gel

TAKEOKA Yukikazu, WATANABE Masayoshi

NIPPON GOMU KYOKAISHI Vol. 77 ( 5 ) page： 155-158 - 158 2004.5

Language：English Publishing type：Research paper (scientific journal) Publisher：THE SOCIRETY OF RUBBER SCIENCE AND TECHNOLOGYY, JAPAN

A periodically ordered interconnecting porous structure could be imprinted in hydrogels by using closest packing silica colloidal crystals as mesoscopically sized templates. The interconnecting porous structure provides fast response to an infinitesimal change of environment for reversible swelling and shrinking of the hydrogels, while the periodically ordered mesoscopical structure endows a structural color in the gel. The structural color with different optical behaviors can be tuned by simply changing the amount of the cross-linker in the pre-gel solutions. The structural color imprinted in the gel is quickly synchronized with the change in the volume of the gels. The newly invented porous hydrogels possess optical properties as environmentally sensitive smart gels.

DOI： 10.2324/gomu.77.155

CiNii Books

CiNii Research

Surface activity and redox behavior of a non-ionic surfactant containing a phenothiazine group Reviewed

Susan, M.A.B.H., Ishibashi, A., Takeoka, Y. and Watanabe, M.

Colloids and Surfaces B-Biointerfaces Vol. 38 page： 167-173 2004

Controlled multistructural color of a gel membrane Reviewed

Y Takeoka, M Watanabe

LANGMUIR Vol. 19 ( 23 ) page： 9554 - 9557 2003.11

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC

A "smart" soft membrane exhibiting controlled multistructural color has been synthesized by the mechanical immobilization of a single side of a polymerized nonclosest packing colloidal crystal. A tapered gel with one fixed surface on a gel-bond film reveals monostructural color. After a partial hydrolysis of the gel to change its volume from the original size, the structural color varies depending on the thickness of the membrane. The tone can be tuned by simply changing the composition of the mixed solvent.

DOI： 10.1021/la0344175

Web of Science

Self-sustaining peristaltic motion on the surface of a porous gel Reviewed

Y Takeoka, M Watanabe, R Yoshida

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY Vol. 125 ( 44 ) page： 13320 - 13321 2003.11

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC

Many materials in living organisms exhibit self-sustaining 
oscillations of chemical and/or physical organization, 
for example,the peristaltic motion of the intestinal tract. 
Some artificial materials have similar properties and thus the 
potential for mimicking biological functions.Now researchers in 
Japan have developed a polymer-gel system that undergoes 
colour changes such that the oscillations can be observed on the 
surface of the gel for the first time (Takeoka,Y.,Watanabe,M.& 
Yoshida,R.Journal of the American Chemical Society 125, 
13320.V13321; 2003).The gel consists of two monomers, 
N-isopopylacrylamide,which controls the swelling and collapse 
of the gel in response to temperature,and a Ru-complex. 
Under certain chemical conditions,the Ru-complex ion 
catalyses a specific reaction (BZ) in which the ion is alternately 
oxidized and reduced as the reaction propagates,resulting in 
colour changes.When the gel is simultaneously subjected to 
changes in temperature,the swelling response of the gel 
occurs in parallel with the BZ reaction,resulting in waves of colour 
changes concomitant with the peristaltic motion.The colour 
tunability of these gels have the potential for use in devices

DOI： 10.1021/ja036904c

Web of Science

PubMed

Tuning structural color changes of porous thermosensitive gels through quantitative adjustment of the cross-linker in pre-gel solutions Reviewed

Y Takeoka, M Watanabe

LANGMUIR Vol. 19 ( 22 ) page： 9104 - 9106 2003.10

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC

"Smart" porous gels with different optical behaviors were synthesized by quantitative adjustment of the cross-linker in pre-gel solutions. A periodically ordered interconnecting porous structure could be created in the gels by using a closest-packing silica colloidal crystal as a template. The interconnecting porosity provides fast response to changes in temperature through the reversible swelling and shrinking of the gels, while the periodically ordered mesoscopic structure endows the porous gels with structural color, which can be tuned by simply changing the amount of the cross-linker in the pre-gel solutions.

DOI： 10.1021/la035142w

Web of Science

Template synthesis and optical properties of chameleonic poly(N-isopropylacrylamide) gels using closest-packed self-assembled colloidal silica crystals Reviewed

Y Takeoka, M Watanabe

ADVANCED MATERIALS Vol. 15 ( 3 ) page： 199 - + 2003.2

Language：English Publishing type：Research paper (scientific journal) Publisher：WILEY-V C H VERLAG GMBH

Smart macroporous hydrogels with a range of optical behavior have been prepared using colloidal crystals as templates. The structural color imprinted in the gel (see Figure and cover) varies with a change in the volume of the gel. It is now possible to build a soft material that displays the various structural colors available to living things.

Web of Science

Template synthesis of poly(N-isopropylacrylamide) minigels using interconnecting macroporous polystyrene Reviewed

M Kumoda, Y Takeoka, M Watanabe

LANGMUIR Vol. 19 ( 3 ) page： 525 - 528 2003.2

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC

Thermosensitive uniform-sized poly(N-isopropylacrylamide) minigels with diameters of several micrometers were synthesized by a double template method using silica particles as original molds. The first template composed of the silica particles produced a macroporous polystyrene as the second template to decide the shape and the size of the minigels. The resultant minigels in the second template covalently interconnect with each other. After the minigels were collapsed in each compartment of the macroporous polystyrene, the separated minigel particles were obtained.

DOI： 10.1021/la020758r

Web of Science

Polymer Gels that Memorize Structures of Mesoscopically Sized Templates Reviewed

Takeoka, Y, Watanabe, M

Langmuir Vol. 18 page： 5977-5980 2003

Simple and precision design of porous gel as a visible indicator for ionic species and concentration Reviewed

H Saito, Y Takeoka, M Watanabe

CHEMICAL COMMUNICATIONS ( 17 ) page： 2126 - 2127 2003

Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY

Here we report the design and synthesis of a novel porous gel for an ionic visible indicator. The rapid-responsive porous gel which reveals color changes depending on a potassium ion concentration was prepared using a templating technique.

DOI： 10.1039/b304306a

Web of Science

Self-Sustaining Peristaltic Motion on the Surface of a Porous Gel Reviewed

Takeoka, Y., Watanabe, M., and Yoshida, R.

J. Am. Chem. Soc Vol. 125 page： 13320 2003

Authorship：Lead author Language：English Publishing type：Research paper (scientific journal)

Many materials in living organisms exhibit self-sustaining
oscillations of chemical and/or physical organization,
for example,the peristaltic motion of the intestinal tract.
Some artificial materials have similar properties and thus the
potential for mimicking biological functions.Now researchers in
Japan have developed a polymer-gel system that undergoes
colour changes such that the oscillations can be observed on the
surface of the gel for the first time (Takeoka,Y.,Watanabe,M.&
Yoshida,R.Journal of the American Chemical Society 125,
13320.V13321; 2003).The gel consists of two monomers,
N-isopopylacrylamide,which controls the swelling and collapse
of the gel in response to temperature,and a Ru-complex.
Under certain chemical conditions,the Ru-complex ion
catalyses a specific reaction (BZ) in which the ion is alternately
oxidized and reduced as the reaction propagates,resulting in
colour changes.When the gel is simultaneously subjected to
changes in temperature,the swelling response of the gel
occurs in parallel with the BZ reaction,resulting in waves of colour
changes concomitant with the peristaltic motion.The colour
tunability of these gels have the potential for use in devices used
for determining oscillations in nonlinear chemical reactions.

Controlled Multi-Structural-Color of a Gel Membrane Reviewed

Takeoka, Y. and Watanabe, M.

Langmuir Vol. 19 page： 9554-9557 2003

Simple and precision design of porous gel as a visible indicator for ionic species and concentration Reviewed

Saito, H., Takeoka, Y. and Watanabe, M.

Chem. Commun. page： 2126-2127 2003

Polymer Gels that Memorize Structures of Mesoscopically Sized Templates Reviewed

Takeoka, Y. and Watanabe, M.

Langmuir Vol. 18 page： 5977-5980 2003

Template synthesis of poly(N-isopropylacrylamide) minigels using interconnecting macroporous polystyrene Reviewed

Kumoda, M., Takeoka, Y. and Watanabe, M.

Langmuir Vol. 19 page： 525-528 2003

Template synthesis and optical properties of chameleonic poly(N-isopropylacrylamide)gels using closest-packed self-assembled colloidal silica crystals Reviewed

Takeoka, Y. and Watanabe, M.

Adv. Mater, Vol. 15 page： 199-201 2003

Simple and Precision Preparation of Porous Gel for Colorimetric Chemical Sensor by Templating Technique Reviewed

Nakayama, D., Takeoka, Y., Watanabe, M., Kataoka, K.

Angew. Chem. Int. Ed. Vol. 42 page： 4197-4200 2003

Tuning Structural Color Changes of Porous Thermo-sensitive Gels Through Quantitative Adjustment of The Cross-linker in Pre-gel Solutions Reviewed

Takeoka, Y. and Watanabe, M.

Langmuir Vol. 19 page： 9104-9106 2003

Simple and precise preparation of a porous gel for a colorimetric glucose sensor by a templating technique Reviewed

D Nakayama, Y Takeoka, M Watanabe, K Kataoka

ANGEWANDTE CHEMIE-INTERNATIONAL EDITION Vol. 42 ( 35 ) page： 4197 - 4200 2003

　 PREV - NEXT 　

<TAKEOKA, Yukikazu>

Papers - TAKEOKA, Yukikazu