格子状のスメクティック液晶相は,メソジェニックペンダント付きの硬棒の螺旋型ポリイソシアン化物である
Takashi Kajitani1, Hisanari Onouchi, Shin-ichiro Sakurai
1Yashima Super-structured Helix Project, Exploratory Research for Advanced Technology (ERATO), Japan Science and Technology Agency (JST), Japan. kajitani@riken.jp
Journal of the American Chemical Society
|June 2, 2011
まとめ
研究者らは,ユニークな液晶特性を持つ新しいマクロモレキュルを発見した. このポリマーは,オーダーされた背骨とサイドグループにより,新しいスメクティック・フェーズを示し,材料科学を前進させる.
科学分野:
- ポリマー化学のポリマー化学について
- マテリアルサイエンス 材料科学
- 液晶は,液体クリスタルです.
背景:
- 螺旋状の背骨とメソゲンサイドグループを持つマクロモリクルは,液晶相を形成することが知られている.
- 分子構造とマクロスコープの相行動の関係を理解することは,高度な材料の設計に不可欠です.
研究 の 目的:
- ポリイソシアン化骨格とメソジェニックキラルペンダントを持つユニークなマクロモレキュルを合成し,特徴づけること.
- このマクロ分子によって表される液晶相,特に新しいスメクティック相を調査する.
- 観測された液晶相の原因となる分子配列を解明する.
主な方法:
- 棒状の螺旋状のポリソシアン化物マクロ分子とメソジェニックのキラルペンダントの合成.
- 濃度依存研究を用いた液晶相の特徴化.
- X線散射と原子力顕微鏡を用いたフィルムの詳細な構造分析.
主要な成果:
- このマクロ分子には,リオトロピックネマティックと,新しい格子状のスメクティック (lat-Sm) 液晶相の両方が表れています.
- 前例のないLat-Sm段階は,ポリマーの骨格と固い棒のサイドグループの両方のスメクティックな順序から生じる.
- X線散射とAFMにより,ポリマーの骨格とメソジェニックペンダントの垂直な配列を持つ傾いたスメクティック層構造が明らかになりました.
結論:
- 新しい液晶相を形成できるユニークなマクロ分子が合成されました.
- 発見されたLat-Sm相は,液晶ポリマーにおける新しいタイプの分子組織を示しています.
- この発見は,高度な材料アプリケーションのための複雑なマクロモレキュルの構造-特性関係に関する洞察を提供します.
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