多面体オリゴメリックシルセスキオキオキサン:空気/水界面のアンフィフィルの新しいクラス
Jianjun Deng1, Joseph T Polidan, John R Hottle
1Department of Chemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA.
Journal of the American Chemical Society
|December 19, 2002
まとめ
トリシラノリソブチル-POSSは,非アンフィフィリックなオクタイソブチル-POSSとは異なり,空気/水のインターフェイスで均一なモノレイヤを形成します. この研究は,材料科学の応用のための不溶性フィルムにおけるPOSS分子の振る舞いを調査しています.
科学分野:
- マテリアルサイエンス 材料科学
- 表面化学について
- ナノテクノロジー ナノテクノロジー
背景:
- 多面体オリゴメリックシルスキオキサン (POSS) は,ユニークなケージ構造を持つナノスケールの分子です.
- POSSデリバティブのインタフェースの振る舞いを理解することは,高度な材料の開発に不可欠です.
研究 の 目的:
- 空気/水界面でのトリシラノリソブチル-POSSとオクタイソブチル-POSSの表面活性と自己組み立てを調査する.
- 部分的に凝縮されたPOSS分子と完全に凝縮されたPOSS分子との接面特性を区別する.
主な方法:
- 分子毎の表面圧力面積のイソテルム (Pi-A) 測定.
- ブルースター角顕微鏡 (BAM) でフィルム形成をリアルタイムで可視化.
主要な成果:
- Trisilanolisobutyl-POSSは,部分的なケージ分子であり,表面活性を示しています.
- この分子は,空気/水界面で圧縮されたときに,均一なモノレイヤーに自己組み立てます.
- 完全に凝縮されたケージ分子であるオクタイソブチル-POSSは,非アンフィフィリックであることが判明しました.
結論:
- 部分ケージのPOSS分子は,オーダーされた単層を形成することができ,表面ベースのアプリケーションの可能性を示しています.
- 完全に凝縮されたPOSS分子には,安定したインターフェイスフィルムに必要なアンフィフィリシティが欠けている.
- POSSケージの構造は,そのインターフェイスの動作と自己組み立て特性に大きな影響を与える.
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