ネマティック相における円盤形および棒形メソゲンの完全な混合性
Paul H J Kouwer1, Georg H Mehl
1Department of Chemistry, University of Hull, Cottingham Road, Hull, HU6 7RX, UK.
Journal of the American Chemical Society
|October 14, 2005
まとめ
混合棒-円盤の形を持つメソゲンは,ネマティック液晶相を示し,他のタイプとよく混合します. 特定の比率で新しいネマティック・フェーズが出現し,バイアキシアル・ネマティック行動の予測と一致する.
科学分野:
- マテリアルサイエンス 材料科学
- 物理化学 物理化学
- 液晶物理学 液晶物理学について
背景:
- 液晶 (LC) は,固体と同流体液体の間の相を示す.
- 棒状と円盤状の分子は,異なるメソフェーズを形成する.
- 分子の形状はLC相の行動と混合性を影響する.
研究 の 目的:
- 棒と円盤状の構造単位を組み合わせた分子における液晶の性質を調査する.
- これらのハイブリッドメソゲンの混合性を,従来の棒形および円盤形メソゲンと探求する.
- 段階的振る舞いを特徴づけ,新しいネマティック・フェーズを特定する.
主な方法:
- ハイブリッド・ロッド・ディスク・メソゲンの合成.
- 段階移行分析のための微分スキャニング熱計 (DSC).
- ポーラライズされた光学顕微鏡 (POM) による相識別.
- バイナリ混合物のフェーズ図構造.
主要な成果:
- ハイブリッド・ロッド・ディスク・メソゲンはネマティック・フェーズ行動を示す.
- ハイブリッドメソゲンと棒状および円盤状メソゲンの間では,ネマティック・フェーズで完全な混合性が観察されました.
- 段階図では,ほぼ同極の円盤・棒の比率で,追加のネマティック・フェーズが特定されました.
結論:
- 混合棒-円盤部分を持つ分子は,ネマティック相における従来のメソゲンと互換性がある.
- 混合性は,複雑な液晶システムの形成をサポートします.
- 特定の組成物における追加のネマティック相の発見は,予測されたネマティック双軸相の実験的証拠を提供します.
関連する概念動画
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