クイラルネマティック液晶におけるヘリカルポリアセチレンの合成,クイラルドーパントとしてクラウンエーサー型ビナフチル誘導体を使用
Kazuo Akagi1, Shouxue Guo, Taizou Mori
1Institute of Materials Science, University of Tsukuba, Ibaraki 305-8573, Japan. akagi@ims.tsukuba.ac.jp
Journal of the American Chemical Society
|October 20, 2005
まとめ
クラウンエーテルビナフチル誘導物 (CEBD) は,キラルネマティック液晶 (N*-LCs) を効果的に誘導した. 螺旋状の構造は螺旋状のポリアセチレン形態に影響を与え,繊維の間隔はN*-LCピッチに匹敵しました.
科学分野:
- マテリアルサイエンス 材料科学
- 有機化学 オーガニック・ケミストリー
- ポリマーサイエンスの科学
背景:
- チラルネマティック液晶 (N*-LCs) は,高度な光学材料にとって極めて重要です.
- チラルのドーパントは,N*-LCsで望ましい螺旋構造を誘導するために不可欠です.
- ドーパント構造とN*-LC特性の関係を理解することが鍵となる.
研究 の 目的:
- 新規のクラウンエーテル型ビナフチル誘導体 (CEBD) をキラルドーパントとして合成する.
- フェニルサイクロヘキサン (PCH) によるネマティック液晶に対するCEBDの回転力を調査する.
- CEBD誘発のN*-LCs内の螺旋型ポリアセチレンの合成とその構造的相関を調査する.
主な方法:
- クラウンエーテル型ビナフチル誘導体 (CEBDs) の一連の合成.
- フェニルサイクロヘキサン (PCH) 導出ネマティック液晶に対するCEBDの回転力の評価.
- 誘導されたN*-LCs内の螺旋型ポリアセチレンの合成と形態学的分析.
主要な成果:
- CEBDは,キラルネマティック (N*) 液晶を成功裏に誘導しました.
- CEBDの回転力は,クラウンエーテルリングのサイズが小さくなるにつれて増加した.
- ヘリカルポリアセチレンの形態はN*-LCのヘリカル構造と相関していた:繊維束の間の距離はヘリカルピッチの半分に等しく,スクルーの方向は反対だった.
結論:
- クラウンエーテル・ビナフチル誘導体は,液晶に対する効果的なキラルドーパントである.
- CEBDsによって制御されるN*-LCsの螺旋構造は,合成された螺旋型ポリアセチレンの形態を決定する.
- この研究は,液晶の螺旋構造とポリマー形態学の間の直接的なリンクを確立しています.
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