2002 Fiscal Year Final Research Report Summary
Thermal properties of optically isotropic liquid crystals
Project/Area Number |
11304050
|
Research Category |
Grant-in-Aid for Scientific Research (A)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
機能・物性・材料
|
Research Institution | Osaka University |
Principal Investigator |
SORAI Michio Graduate School of Science Professor, 大学院・理学研究科, 教授 (50028172)
|
Co-Investigator(Kenkyū-buntansha) |
MIYAZAKI Yuji Graduate School of Science Research Associate, 大学院・理学研究科, 助手 (70252575)
SAITO Kazuya Graduate School of Science Associate Professor, 大学院・理学研究科, 助教授 (30195979)
|
Project Period (FY) |
1999 – 2002
|
Keywords | Thermotropic liquid crystal / Lyotropic liquid crystal / Cubic liquid crystal / Phase transition / Entropy / Heat capacity / Potically isotropic liquid crystal |
Research Abstract |
1.Heat capacity measurement ofACBC(16) Based on heat capacity rneasurement for a cubic mesogen ACBC(16), we revealed complicoted phasc relationship including newly found crystalline plaases. We also found a glass transition in the new solid phase. The broad heatcapacity anomaly appearing in the isotropic liquid stat was stnpercooed, suggesting that the evct oecurring at the hump be not directly related to the cubictoisotropic liquid phase transition. 2. Quasi-binary picture of thermotroplc Iiquid crystals A quasibinary picture of thermotropic liquid crystals is proposed on the basis of therrnodynantic observations. The conformational entropy of long alkyl chains attached to a (semi)rigid core of mesogenic molecules indicates that the chain is higlaly disordered in liquid crystalline states. These disordered chains seuve as "intramolecular solvenis" or "selfsolvent" judging from a close resemblance between phase diagrams of neat (against chain length) aed binary (against composition) systems. The application of the quasibinary picture to the classic examples of thermotropic cubic mesophases shows that the essential structttral motif is triply periodic minimal surface. This model is not only cousistent witht available experimental restults but also naturally explains smaller heat capacities of cubic mesophases than neighboring liquid crystalline phases.
|
Research Products
(14 results)
-
-
-
-
-
-
-
-
[Publications] K, Saito, T, Shinhara, T, Nakamoto, S, Kutsumizu, S, Yano, M, Sorai: "Degree of disorder in cubic mesophases in thermotropics: Thermodynamic study of a liquid crystal showing two cubic mesophases"Phys. Rev. E. 65. 031719 (2002)
Description
「研究成果報告書概要(欧文)」より
-
-
-
-
-
[Publications] Y, Hayshi, M, Shinyashiki, S, Yagihara, K, Yoshiba, A, Teramoto, N, Nakamura, Y, Miyazaki, M, Sorai, Q, Wang: "Ordering in Aqueous Polysaccharide Solutions: I. Dielectric Relaxation in Aqucous Solutions of a Triple-Helixal Polysaccharide Schizophyllan"Biopolymers. 63. 21-31 (2002)
Description
「研究成果報告書概要(欧文)」より
-
[Publications] K, Yoshiba, T, Ishino, A, Teramoto, N, Nakamura, Y, Miyazaki, M, Sorai, Q, Wang, Y, Hayashi, M, Shinyashiki, S, Yagihara: "Ordering in Aqueous Polysaccharide Solutions: II. Optical Rotation and Heat Capacity of Aqueous-Solutions of a Triple-Helical Polysaccharide Schizophyllan"Biopolymers. 63. 370-381 (2002)
Description
「研究成果報告書概要(欧文)」より