2004 Fiscal Year Final Research Report Summary
Study on dynamic interaction of nematogen and polymer by means of hererodyne light scattering method
| Project/Area Number |
15540390
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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 |
Biophysics/Chemical physics
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| Research Institution | Nagoya University |
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Principal Investigator |
MASTOKA Tatsuro Nagoya University, Graduate School of Engineering, Associate Professor, 大学院・工学研究科, 助教授 (60252269)
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| Co-Investigator(Kenkyū-buntansha) |
KODA Shinobu Nagoya University, Graduate School of Engineering, Professor, 大学院・工学研究科, 教授 (10126857)
YAMAGICHI Tsuyoshi Nagoya University, Graduate School of Engineering, Research Associate, 大学院・工学研究科, 助手 (80345917)
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| Project Period (FY) |
2003 – 2004
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| Keywords | heterodyne light scattering method / liquid crystal-polymer mixture / 5CB / polystyrene / reorientational relaxation time / translational-reorientational / intrinsic viscosity / miscibility |
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| Research Abstract |
In recent years, extensive studies on the phase transition behaviors of mixtures of liquid crystals and polymers have been carried out. Little studies, however, have been performed on the dynamics. Since the dimension of the polymer molecules are much larger than that of liquids crystal molecules, it is very interesting how the addition of polymer affects the reorientational and translational behavior of liquid crystal in the polymer and liquid crystal mixtures.
In this study, the power spectra of the polarized and depolarized light scattering were obtained by means of the light scattering method based on an optical heterodyne technique. The reorientational relaxation time and the constant attributed to the coupling between reorientational and translational modes of molecular motions in anisotropic molecules, R, were obtained from the polarized and depolarized spectra in the mixture of polystyrene(PS) and 4-cyano-4'-pentyl biphenyl (5CB) in the isotropic phase. We also measured the intrinsic viscosity to study the miscibility of PS in the mixtures
Large influence was observed when the molecular weight of PS is small and the value of R largely decreases with increasing PS concentration when the temperature is near the phase transition point. The intrinsic viscosity for the mixtures for small molecular weight PS increases when temperature decreases to the near the phase transition points. This indicate that miscibility increases when temperature decreases to the near the phase transition points. The good miscibility leads to the large influence on the reorientational relaxation time and R.Little influence was observed on the reorientational relaxation time and R when the molecular weight of PS is large. The intrinsic viscosity of the mixtures for large molecular weight indicates that the 5CB is a poor solvent for PS. This leads to the little influence when the molecular weight of PS is large.
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