ジェミニ二カルボキシラート表面活性物質からの異常に安定した水性リオトロピクジロイド相
Gregory P Sorenson1, Keiva L Coppage, Mahesh K Mahanthappa
1Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States.
Journal of the American Chemical Society
|September 6, 2011
まとめ
新しいアニオン基の表面活性剤は,予想外にも安定した液晶ガイロイド相を形成する. この発見は,二連続の立方体形態を持つ先進的な材料のための新しい設計戦略を提供します.
科学分野:
- マテリアルサイエンス 材料科学
- 超分子化学 超分子化学
- コロイド科学 コロイド科学
背景:
- 二連続の立方体 (Q相) を有する水性リオトロピク液晶 (LLC) は,分離とイオン輸送に有望である.
- 現在,Q相を形成するアンフィフィルのための普遍的な設計規則は存在しない.
- カチオンのジェミニ表面活性剤は,Q相形成の傾向を示しているが,これは普遍的に確立されていない.
研究 の 目的:
- 安定した双連続立方LLCを形成するアニオンゲミニ表面活性剤の可能性を調査する.
- Q相形成を好む両生類の設計基準を確立する.
- LLC形態学に対する分子構造の影響を調査する.
主な方法:
- アリファートカルボキシル酸から新しいアニオンゲミニ表面活性物質のモジュール合成.
- アルキルスペーサーの長さと表面活性物質の対比値 (Na+,K+, (CH3) 4N+) の体系的な変化.
- 温度と濃度の範囲で形成された液晶相の特徴.
主要な成果:
- アニオニックジェミニ表面活性剤は,ガイロイド LLC フェーズを形成する強い傾向を示した.
- これらのジロイド相は,25°Cから100°Cまでの前例のない安定性を示した.
- 安定したQ相形成は,広いアンフィフィール濃度窓 (重量20%まで) で観察されました.
結論:
- アニオニックジェミニ表面活性剤は,技術的に関連する二連続体立方LLC形態の安定化に有効です.
- 分子設計,特にアルキル間隔長と対対離子選択は,Q相形成に大きく影響する.
- この研究は,安定した二連続体立方液晶相のためのアンフィフィルの設計に関する重要な洞察を提供します.
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