ポリマー対ポリマー表面の粘着と摩擦メカニズム
Nobuo Maeda1, Nianhuan Chen, Matthew Tirrell
1Department of Chemical Engineering, College of Engineering, University of California, Santa Barbara, CA 93106, USA.
Science (New York, N.Y.)
|July 20, 2002
まとめ
ポリマー表面の摩擦と粘着は,チェーンダイナミクスに依存しています. クロスリンクされたポリマーは,クロスリンクされていないものよりも低い摩擦を示し,表面鎖の修正後に摩擦と粘着が増加することが観察されています.
科学分野:
- マテリアルサイエンス 材料科学
- ポリマーサイエンスの科学
- トリボロジ トリボロジ トリボロジ
背景:
- ポリマーの表面特性を理解することは,アプリケーションにとって極めて重要です.
- 粘着と摩擦は,ポリマー表面相互作用の重要なパラメータです.
研究 の 目的:
- 聚合物鎖のダイナミクスが粘着と摩擦に及ぼす影響を調査する.
- 表面鎖の構造が tribological 行動にどのように影響するかを調査する.
主な方法:
- 表面力装置を使って,ガラス化温度より低いポリマー表面を研究した.
- クロスリンクされたおよびクロスリンクされていないポリマーサンプルの両方を検査しました.
- 鎖分裂を誘導した後の粘着と摩擦の変化を調査した.
主要な成果:
- 摩擦力は,クロスリンクされたポリマーの場合,クロスリンクされていないものと比較して大幅に低かった.
- 粘着ヒステレスと摩擦は,表面層の鎖分裂後に大幅に増加した.
- 交絡型から長鎖型,準自由型の端面への移行は,粘着と摩擦の増大と相関しています.
結論:
- ポリマー-ポリマー粘着ヒステレスと摩擦は,表面ポリマーセグメントのダイナミックな再配置によって制御されます.
- 表面連鎖の状態は,トライボロジカルな性質に重大な影響を及ぼします.
- 発見は,表面チェーンダイナミクスを制御することによって,ポリマーの表面粘着と摩擦を調節する方法を示唆しています.
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