Study on Smectic Liquid Crystalline Structure in Main-Chain Polyester

主链聚酯层列液晶结构的研究

• 批准号: 01550688
• 负责人: WATANABE Junji
• 金额: $ 1.09万
• 依托单位: Tokyo Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1989
• 资助国家: 日本
• 起止时间: 1989 至 1990
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-01550688/
• 关键词: Thermotropic lqiuid crystal; Polyester; Layer structure; Conformation; Even-odd oscillation; Smectic liquid crystal; 層構造; 光学活性; 強誘電; らせん構造; 高分子液晶; ビベンゾエイト

The thermotropic liquid crystal nature of mainーchain polyesters that can be constructed by an alternative arrangement of the p,p'ーbibenzoate unit as a mesogenic group and the alkanediol as a flexible spacer. The polyesters are designated BB-n where n is the number of methylene units in the diol. This homolog ous series of BB-n (n = 3-9) invariably form smectic mesophases whose isotropization temperatures and entropies exhibit an evenーodd oscillation with the number of intervening methylene units, n. The evenーodd nature of the methylene unit also reflected the thickness of smectic layers, with a larger layer thickness in the even series. Comparing the observed thickness with the calculated ones based on the rotational isomeric state model, we concluded that the evenーodd nature is strongly related to the polymer chain conformations and that the different types of smectic structures can be formed between the two. In even numbered polyesters there is formed a normal smectic A phase in which both axes of the polymer chain and mesogenic group lie perpendicular to the layers. In oddーnumbered ones, in contrast, the smectic structure was found to be a type of smectic C in which the average chain axis of the polymer is perpendicular to the layer, but the mesogenic groups are tilted with respect to the layer normal. Such structural characteristics are also confirmed from the xーray and optical microscopic studies for the oriented smectic phases.

主链聚植物的热液晶性质可以通过P，P'-Bibenzoate单元作为中源组和烷烃作为柔性垫片的替代排列来构建。聚酯被指定为bb-n，其中n是二醇中甲基单元的数量。这一系列的BB-N（n = 3-9）总是形成近晶中介液，其各向同性温度和熵表现出均匀的ODD振荡，中间的甲基单元数量，n。亚甲基单元的均匀性质也反映了近晶层的厚度，均匀层的层厚度较大。将观察到的厚度与基于旋转异构体模型计算的厚度进行比较，我们得出结论，均匀的性质与聚合物链构象密切相关，并且可以在两者之间形成不同类型的近晶结构。在什至编号的聚酯群体中，形成了正常的近晶型一个相，其中聚合物链的两个轴和中源性组都垂直于层。相比之下，在奇数的结构中，发现近晶结构是一种近晶型C，其中聚合物的平均链轴垂直于该层，但是间质基团相对于层正常。从定向的近晶相位的X射线和光学显微镜研究中也证实了这种结构特征。

项目成果

JUNJI WATANABE and MANABU HAYASHI: "Thermotropic Lequid Crystals of Polyesters Having a Mesogenic Bibenzoate Unit. 1." Macromolecules. 21. 278--280 (1988)

JUNJI WATANABE 和 MANABU HAYASHI：“具有介晶联苯甲酸酯单元的聚酯热致液晶。1。”

"Thermotropic Liquid Crystals of Polyestors Having a Mesogenic p'p'- Bibenzoate Unit.2." Macromolecules. 22. 4083-4088 (1989)

“具有介晶 pp-联苯甲酸酯单元的聚酯的热致液晶。2。”

渡辺 順次: "液晶ー多彩な分子設計と新規機能開発" 高分子. 39. 369-369 (1990)

Junji Watanabe：“液晶 - 多样化分子设计和新功能开发”聚合物 39. 369-369 (1990)

JUNJI WATANABE and MANABU HAYASHI: "Thermotropic liquid crystals of polyesters having a mesogenic Bibenzoate unit. 2." Macromolecules. 22. 4083--4088 (1989)

JUNJI WATANABE 和 MANABU HAYASHI：“具有介晶联苯甲酸酯单元的聚酯热致液晶。2。”

Junji Watanabe Manabu Hayashi: "Thermotropic liquid Crystals of Polyesters Having a Mesogenic PーP´ーBibenzoate Unit.1." Macromolecules. 21. 278-280 (1988)

Junji Watanabe Manabu Hayashi：“具有介晶 P-P´-联苯甲酸酯单元的聚酯的热致液晶。1。” 21. 278-280 (1988)。