アンフィフィリック半月状の微粒子は,コロイドの選択的吸収によって形成されます
Shin-Hyun Kim1, Alireza Abbaspourrad, David A Weitz
1School of Engineering and Applied Sciences and Department of Physics, Harvard University, Cambridge, Massachusetts, USA.
Journal of the American Chemical Society
|March 23, 2011
まとめ
研究者らは,マイクロフリウジックを用いて,半月形のアンフィフィリック粒子を作り出した. これらの粒子は,防水層を形成することで,油と水のエムルションを安定させ,ドロップレット凝結を防止します.
科学分野:
- 材料科学 材料科学とは
- コロイドと表面の化学
- マイクロフリウジック
背景:
- エムルションの安定化は,様々な産業において極めて重要です.
- 伝統的なエムルション安定剤には限界があります.
- 新しいアンフィフィリック粒子を開発することで,新しい安定化戦略が生まれます.
研究 の 目的:
- モノディスパース,半月状の形状のアンフィフィリック粒子を生成するためのマイクロフリウイド法を開発する.
- これらの粒子の使用を,オイル・イン・ウォーターエムルションの安定化に研究する.
- これらの新しいマイクロ粒子による安定化のメカニズムを理解するために.
主な方法:
- theta (θ) 形の毛細血管微流体装置を使用して,制御された油相注入を行いました.
- フォトキュアブルモノマーとフッ素炭素油をシリカコロイドと混合して使用した.
- 紫外線で誘発されたポリメリゼーションと選択的コロイド吸収による誘発粒子形成.
- 水-エタノール混合物におけるエムルションの安定性を評価した.
主要な成果:
- 単分散型,半月形状の微粒子を成功裏に準備しました.
- シリカコロイドが選択的に油と水のインターフェイスに吸収することを実証しました.
- 油滴を安定させるこれらのアンフィフィリック粒子の能力を確認しました.
- 高表面密度で粒子の不動化が観察され,滴の集積を防ぐ.
結論:
- マイクロフリウジックは,アニゾトロプ的アンフィフィリック粒子を合成するための効果的な経路を提供します.
- 半月の形状の粒子は,オイル・イン・ウォーターエムルションの堅固な安定性を提供します.
- 十分な表面密度での粒子の固定化は,凝結を防ぐための鍵です.
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