2003 Fiscal Year Final Research Report Summary
Surface Relief Grating Formation Using Photochromic Amorphous Molecular Materials
Project/Area Number |
14540532
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
機能・物性・材料
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Research Institution | Osaka University |
Principal Investigator |
NAKANO Hideyuki Osaka University Graduate School of Engineering, Associate Professor, 大学院・工学研究科, 講師 (00222167)
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Co-Investigator(Kenkyū-buntansha) |
KAGEYAMA Hiroshi Osaka University Graduate School of Engineering, Research Associate, 大学院・工学研究科, 助手 (50294038)
SHIROTA Yasuhiko Osaka University Graduate School of Engineering, Professor, 大学院・工学研究科, 教授 (90029091)
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Project Period (FY) |
2002 – 2003
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Keywords | Amorphous Molecular Material / Photochromic Amorphous Molecular Material / Photochromism / Azobenzene / Surface Relief Grating Formation / Hologram / Diffraction Efficiency / Glass Transition Temperature |
Research Abstract |
Recently, formation of surface relief grating (SRG) by irradiation of amorphous films of azobenzene-functionalized polymers with two coherent laser beams has received a great deal of attention. SRG formation takes place by the mass transport induced by the photoisomerization of the azobenzene chromophore. Although a few models for SRG formation have been proposed, detailed mechanism has not yet been elucidated. As a part of our studies on amorphous molecular materials, we have proposed a new concept, "photochromic amorphous molecular materials" and have created two families of photochromic amorphous molecular materials based on azobenzene and dithienylethene. Photochromic amorphous molecular materials constitute a new class of photochromic materials that form uniform amorphous films by themselves without polymer binders. They have an advantage that there is no dilution of photochromic chromophores relative to photochromic polymers and composite polymer systems, where low molecular-weight photochromic compounds may crystallize at high concentrations. In the present study, we have designed and synthesized several novel photochromic amorphous molecular materials and elucidated their photochromic properties as amorphous films as well as in solution. In addition, SRG formation using azobenzene-based photochromic amorphous molecular materials has been investigated, showing that they also constitute a new class of SRG-forming materials. The diffraction efficiency and the modulation depth of SRG formed on amorphous films of photochromic amorphous molecular materials were found to increase with increasing the glass-transition temperatures. Comparative study of SRG formation between a photochromic amorphous molecular material and the corresponding vinyl polymer with the same pendant group showed that SRG is formed more rapidly for the amorphous molecular material than for the vinyl polymer.
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Research Products
(12 results)