小角X線散射と原子力顕微鏡を用いたAOT+フェノルオルガンゲルの微細構造の決定
B A Simmons1, C E Taylor, F A Landis
1Contribution from the Department of Chemical Engineering, Department of Chemistry, Tulane University, New Orleans, Louisiana 70118, USA.
Journal of the American Chemical Society
|July 18, 2001
まとめ
アニオン性表面活性物質ビス・(2-エチルヘキシル) サルフォスカルシネート (AOT) は,非極性溶媒中のp-クロロフェノールでオルガンゲルを形成する. これらのゲルは,AFMとSAXSによって可視化されるユニークな繊維束構造を示しています.
科学分野:
- 超分子化学 超分子化学
- マテリアルサイエンス 材料科学
- 物理化学 物理化学
背景:
- オルガノゲルは,固体ネットワーク内で液体をカプセル化できる材料です.
- 表面活性物質は,溶液中の様々な構造に自己組み立てることができる分子です.
- 表面活性物質の自己組成を理解することは,新しい材料の設計に不可欠です.
研究 の 目的:
- bis(2-エチルヘキシル) 硫黄糖酸塩 (AOT) とp-クロロフェノールによって形成されたオルガノゲルの形成と微細構造を調査する.
- 自己組み立てプロセスにおける非極性溶媒の役割を明らかにする.
- 結果となるオルガンゲルの分子構造を特徴付けるため.
主な方法:
- 様々な非極性溶媒にAOTとp-クロロフェノールを使用したオルガンゲル形成.
- 構造分析のための小角X線散射 (SAXS).
- 直接視覚化のためのタッピングモード原子力顕微鏡 (AFM).
主要な成果:
- オルガノゲルは,ベンゼン,トルーエン,アルケーンなどの溶媒の中で,AOT:フェノルの1:1のモラ比で自発的に形成されます.
- SAXSのデータは,繊維に自己組み立てられるAOT/フェノール鎖の溶媒依存の特徴的な長さのスケールを明らかにしています.
- AFM画像は,オルガンゲル構造が集積された繊維束で構成されていることを確認しています.
結論:
- オーガノゲルの構造は,水素結合のAOT/フェノール鎖を基にして,繊維を形成し,その繊維は束にまとまります.
- 3つの異なる長さのスケール (糸,繊維,束) を有する階層的な分子構造が提案されています.
- 溶媒の化学的性質は,自己組み立てと,その結果ゲルの性質に大きな影響を与えます.
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