| Project/Area Number |
09640477
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
物理学一般
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| Research Institution | Ochanomizu University (1998-1999)
The University of Tokyo (1997) |
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Principal Investigator |
IMAI Masayuki Faculty of Science, Ochanomizu Univ. Associate Professor, 理学部, 助教授 (60251485)
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| Co-Investigator(Kenkyū-buntansha) |
今井 正幸 お茶の水女子大学, 理学部, 助教授 (60251485)
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| Project Period (FY) |
1997 – 1999
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| Project Status |
Completed (Fiscal Year 1999)
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| Budget Amount *help |
¥3,300,000 (Direct Cost: ¥3,300,000)
Fiscal Year 1999: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 1998: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1997: ¥2,200,000 (Direct Cost: ¥2,200,000)
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| Keywords | first order phase transition / incubation time / phase transition dynamics / pretransition phenomena / complex liquids / polymer / surfactant / liquid crystal / 両親媒性分子 / 分子膜 / モルフォロジ-転移 / 小角散乱 / モルフォロジー転移 |
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| Research Abstract |
In the first order phase transitions, we sometimes observe a waiting time prior to the phase transition, so-called induction period (incubation time). According to the classical nucleation theory the induction period is the time needed to form critical nucleus. However systems having multi-order parameters, such as complex liquids will show a variety of incubation time or pretransition behaviors arisen from coupling of the order parameters. The purpose of this study is to reveal the kinetics of the incubation time or pretransition phenomena in the first order phase transition of the complex liquids.
1) Ordering process of polymers during the induction period of crystallization.
We found the ordering process in the induction period of polymer crystallization.When a poly(ethylene terephthalate) glass was annealed just above the glass transitio temperature, a new peak in the small angle x-ray scattering profiles appeared prior to the crystallization. The quantitative analysis of this peak revealed that a spinodal decomposition type of phase transition occurs as a preparatory process of the crystallization. The origin of this phenomenon is explained as the parallel orientational ordering of the rodlike polymer segments.
2) Pretransition phenomena observed in a order-order transition of a surfactant/water system.
We investigated the lamellar structure prior to a lamellar-to-gyroid transition in a nonionic surfactant/water system. In high temperature region (T > 65℃) the lamellae show undulation fluctuations. When the temperature approached to the lamellar-to-gyroid transition temperature, the excess diffuse scattering grew around a first lamellar peak and then transformed to a (211) peak of the gyroid lattice at the transition temperature. This excess diffuse scattering arises from modulation or perforation of the lamellae. This modulated lamellae is the equlibrim pretransition structure and corresponds to the least stable mode of the lamellar structure.
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