アルカン液滴の移動性を特に改善するための物理的アプローチ
Dalton F Cheng1, Chihiro Urata, Benjamin Masheder
1National Institute of Advanced Industrial Science and Technology, 2266-98, Anagahora, Shimoshidami, Moriyama-ku, Nagoya, Aichi 463-8560, Japan.
Journal of the American Chemical Society
|June 1, 2012
まとめ
研究者は,ポリ・ディメチルシロキサン (PDMS) ブラシフィルムを使用して,表面上の液滴の動きを制御しました. 低ポリマー分子量と探査液の表面張力が抵抗を低下させ,液滴の動きを容易にします.
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
- ポリマーサイエンスの科学
背景:
- 液体と基板の相互作用を制御することは,様々な用途において極めて重要です.
- ポリマーブラシフィルムは,調節可能な表面特性を提供します.
- 液体ドロップの流動性を影響する要因を理解することは,表面設計に不可欠です.
研究 の 目的:
- 表面上の液滴運動抵抗に対するシームレスな制御を実証するために.
- ポリマーの分子量の影響を調査し,液滴の流動性に対する液体の性質を調査する.
- ダイナミック・デウェッティングの接触角度ヒステレシスの計算のためのさまざまな方法を評価する.
主な方法:
- 異なる分子量を持つ溶融線形ポリ・ディメチルシロキサン (PDMS) ブラシフィルムを使用しています.
- 液体の落下運動抵抗を評価するために,接触角度 (CA) ヒステレスと傾斜角度測定を使用しました.
- 水,n-ヘクサデカーン,n-ドデカーン,n-デカーンを含む調査した探査液.
- 標準 (Δθ) とコシン修正 (Δθ(cos)) の両方を用いて計算されたCAヒステレシス.
主要な成果:
- 液滴運動抵抗は,PDMS分子量と探査液表面張力を調節することで,うまく制御できました.
- 低ポリマー分子重量と低探査液表面張力が,液滴の動きに対する抵抗を低下させた.
- ポリマーの分子量が増えると水滴の移動性が低下し,n-デカン滴は最小限の抵抗を示した.
- コシヌス修正CAヒステレス (Δθ(cos)) は,ダイナミック・デウェッティング行動のより有利な見積もりを提供した.
結論:
- PDMSブラッシュフィルムは,極性液体と非極性液体の液滴運動抵抗を調節できる制御を可能にします.
- 分子重量と腫れによって影響されるポリマー鎖の移動性は,液滴の動きを制御する鍵です.
- 接触角度ヒステレシスの計算方法の選択は,ダイナミックな濡れ処理の正確な評価に影響します.
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