1997 Fiscal Year Final Research Report Summary
Ferroelectric nematic phases formed from polar rod-like polymers
| Project/Area Number |
08455450
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
高分子構造・物性(含繊維)
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| Research Institution | Tokyo Institute of Technology |
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Principal Investigator |
WATANABE Junji Tokyo Institute of Technology, Professor, 工学部, 教授 (90111666)
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| Project Period (FY) |
1996 – 1997
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| Keywords | rod-like polymer / nematic phase / ferroelectric phase / second harmonic generation / non-linear optics / polyester / dipale moment / estor linkage |
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| Research Abstract |
The aromatic polyesters composed of hydroxy benzoic acid and hydroxy naphthoic acid were prepared with different fractions of two components and different degrees of polymerization, and their thermotropic liquid crystalline behavior and structures were examined. The most interesting fact obtained is that the polymers with the degree of polymerization more than 30-40 can form a novel nematic liquid crystals with polar ordering along the nematic director. The second harmoinc generation (SHG) profiles as a function of incident of SH polarizations are well simulated under the model of Cs symmetry with a mirror plane rotationally disordered about the molecular axis. This means that the polar nematic liquid crystal is biaxial in which the polarity exists along the c-director as well as n-director. Cs symmetry can be altered to C v by the introduction of meta-hydroxy benzoic acid. This can be well explained by the occurence of the kink structure which can extinct the polarity perpendicular to the chain axis.
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