水溶性逆性ネオジミウム ((III) コーディネーションポリマーの線形リオロジー
Tina Vermonden1, Mies J van Steenbergen, Nicolaas A M Besseling
1Laboratory of Organic Chemistry, Dutch Polymer Institute/Wageningen University, Dreijenplein 8, 6703 HB Wageningen, The Netherlands.
Journal of the American Chemical Society
|December 2, 2004
まとめ
本研究では,ネオジミウム (III) イオンによって形成された可逆調整ポリマーネットワークを調査しています. これらの粘性弾性材料は,線形均衡ポリマーダイナミクスと熱可逆ゲル行動を示す.
科学分野:
- ポリマー化学のポリマー化学について
- マテリアルサイエンス 材料科学
- 整形外科医 整形外科医 整形外科医
背景:
- コーディネーションポリマーには調節可能な特性があります.
- 彼らのレオ学的行動を理解することは,アプリケーションにとって極めて重要です.
- リバーシブル・ネットワークは,自己治癒性や刺激反応性のある材料にとって興味深いものです.
研究 の 目的:
- 新しい可逆調整ポリマーネットワークのリオロギーを調査する.
- 水溶液中のこれらのネットワークの粘弾性特性を特徴付ける.
- ネットワークダイナミクスに対する濃度と温度の影響を決定する.
主な方法:
- レオロギー的な測定 (粘着弾性,リラックス時間,粘度) が行われました.
- マクスウェルのモデルは,材料の振る舞いを記述するために使用されました.
- 濃度および温度依存性に関する研究が行われました.
主要な成果:
- 高濃度では,ポリマーネットワークは粘性弾性を示した.
- 材料の性質は,線形均衡ポリマーのケイツモデルと一致しています.
- ゲルは,冷却時に即座に回復する特性を有する熱可逆性を示した.
結論:
- 研究されたネットワークは,最小限のクロスリンクを伴う線形均衡ポリマーとして振る舞います.
- 熱可逆性の性質は,高温で液体のような振る舞いを可能にします.
- ポリマーダイナミクスの活性化エネルギーは49 kJ/molであった.
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