陽性イオン性液体内のカチオン性水泡の自発的な熱可逆的形成
Carlos R López-Barrón1, Dongcui Li, Leo DeRita
1Center for Neutron Science, Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, USA.
Journal of the American Chemical Society
|October 4, 2012
まとめ
研究者らは,プロティックイオン液体 (エチルアモニウム窒素) の内にある純粋なカチオン表面活性物質 (ダイドセイルジルジメチルアモニウムブロミド) の自発的な膀形成を発見した. この発見は,このようなシステムにおけるバランスベジクルとスポンジ相の最初の証拠を提供します.
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
- コロイド科学 コロイド科学
背景:
- 安定したベジキュラー構造は,様々な用途で非常に求められています.
- 表面活性剤系では,真の熱力学均衡下では自発的に膀を形成するものはほとんどありません.
- イオン性液体などの新型溶媒における自己組み立ての理解は極めて重要です.
研究 の 目的:
- 陽性イオン液中の純粋なカチオンの二重尾の表面活性剤から自発的に膀の形成を調査する.
- 先進的な分散と顕微鏡技術を使用して,その結果生じる膀構造と相を特徴づける.
- このシステムにおける均衡ベジクルの存在に対する実験的証拠を提供すること.
主な方法:
- 構造的性質を決定するために,小角と超小角の中性子散射 (SANS/USANS) を行う.
- 溶液の粘度と流動性を評価するためのリオロジー.
- 膀の形状とサイズを直接可視化するための明るいフィールド顕微鏡.
主要な成果:
- エチラモニウム窒素 (EAN) のディドデシルジメチラモニウムブロミド (DDAB) の自発的な膀形成の最初の実験的証拠.
- 2つの共存する膀を含む相の識別:巨大な膀とスポンジ相の低密度,高粘度相,および大きな膀の薄く,高密度相.
- 膀は,異なる熱力学的経路を介して自発的に形成され,一貫したサイズ分布を示し,真の熱力学的均衡をサポートします.
- 陽性イオン液体内のイオン交換とソルボフォビック作用により,平衡ベジクルとL(3) 段階形成の促進.
結論:
- この研究は,陽性イオン性液中の純粋なカチオン性表面活性剤から均衡ベジクルが自発的に形成されることを示しています.
- イオン液体内のイオン交換とソルボフォビック相互作用は,これらの安定した構造の形成の主要な原動力です.
- この研究は,イオン性液体環境における自己組み立てソフト材料の設計に新しい道を開きます.
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