フォトクロミック・ヒドラゾンを用いて液晶相転換を駆動する
Mark J Moran1, Mitchell Magrini2, David M Walba2
1Department of Chemistry , Dartmouth College , Hanover , New Hampshire 03755 , United States.
Journal of the American Chemical Society
|October 9, 2018
まとめ
研究者は,液晶 (LC) のための新しいキラルドーパントを開発しました. このドーパントは,光制御された自己組み立てを可能にし,調節可能な光学特性と新しい光ゲートされた光学ウィンドウをもたらします.
科学分野:
- 柔らかい物質の物理
- 材料科学
- 有機化学
背景:
- 柔軟な物質の性質のダイナミックな操作は 適応性のある機能材料の鍵です
- 液晶 (LC) は,自己組み立てによって調節可能な光物理的性質を示す.
- 外部刺激でLCの自己組み立てを制御することは,高度なアプリケーションに不可欠です.
研究 の 目的:
- ネマティック液体結晶のための新型のキラルドーパントを設計し合成する.
- LCの自己組み立てと光物理学的性質に対する光誘発制御を調査する.
- LCの光誘発相変数に基づく光ゲートされた光学窓を実証する.
主な方法:
- イソソルビド・スキャフォルドとビスタブルなヒドラゾンベースのライトスイッチを備えた新しいキラルドーパントの合成.
- ドーピング ネマティック液晶 (5CB) と合成キラルドーパント.
- 特定の光の波長 (例えば,青い光) を使用してドーパントの光異性化.
- 光学顕微鏡検査や光譜検査などの技術を用いたLC相行動と光物理学的性質の特徴化.
主要な成果:
- キラルドーパントはネマティックLCの自己組織化と光物理的性質を成功裏に制御した.
- ライトスイッチのバイスタビリティは,異なる波長を反射する様々な螺旋組の運動トラップを可能にしました.
- 青い光で照射すると,ドーピングされた5CBで,コレステリックからスメクティックA*相への同熱相移行が誘発される.
- この相変化により,LC膜の透明性が調節され,光ゲートされた光学窓が形成された.
結論:
- ライトスイッチ可能なユニットに基づいた新しいキラルドーパントは,LCの自己組み立てと光学特性を正確に制御します.
- 証明された同熱相移行は,光に反応する材料のための新しいメカニズムを提供します.
- 開発された光ゲート光学ウィンドウは,アダプティブディスプレイとスマートウィンドウで潜在的なアプリケーションを持っています.
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