化学的に異なったポリマーマトリックスにおけるポリマー移植ナノ粒子の湿潤-湿潤と分散-集積の移行は異なる
Tyler B Martin1,2, Katrina Irene S Mongcopa3, Rana Ashkar4,5
1Department of Chemical and Biomolecular Engineering, University of Delaware , Newark, Delaware 19716, United States.
Journal of the American Chemical Society
|August 4, 2015
まとめ
異なるマトリックスにポリマーで埋め込まれたナノ粒子は,分散状態から集積状態への鋭い相変化を示します. この振る舞いは化学的に同一の複合材料と自由ポリマー混合物とは異なる.
科学分野:
- 材料科学
- ポリマー科学
- ナノテクノロジー
背景:
- ポリマーマトリックスにポリマー・インプラントナノ粒子 (PGN) が組み込まれていることは,先進的な材料にとって極めて重要です.
- これらの複合材料の段階的振る舞いを理解することは,形状と性質を制御する鍵です.
- グラフトとマトリックスポリマーの間の温度依存の相互作用は,ブレンド形態に影響します.
研究 の 目的:
- 化学的に異なったポリマーマトリックスにおけるPGNの相変化の振る舞いを調査する.
- 観察された相変異を湿潤-脱湿変異と区別する.
- 化学的に同一のPGN複合材料と自由ポリマー混合物との比較です.
主な方法:
- 粗い粒子の分子ダイナミクスシミュレーション
- X線散射実験について
- デュテラートポリシュチレン (dPS) 移植シリカとポリウニルメチルエーテル (PVME) マトリックスを用いた中性子散乱実験.
主要な成果:
- 温度上昇に伴い,分散型から集積型への急激な相変化が観察された.
- この移行は,混合物の成分間のますます排斥的な効果的な相互作用によって引き起こされます.
- 観察された移行は,化学的に同一のシステムとは異なり,連続的な湿潤-脱湿移行とは異なります.
結論:
- 化学的に異なるポリマーを持つPGNの相変異は,湿潤現象と根本的に異なる.
- この発見は,これらのトランジションが 移植マトリックス複合体で同義語であるという長年の仮定に異議を唱えています
- この研究は,特定のエンタルピック相互作用を持つPGNシステムにおけるユニークな自己組み立てメカニズムを強調しています.
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