熱反応ダイナマー: 熱誘導によるアンフィフィリックポリ (アシルヒドラゾン) の可逆性鎖延長
J Frantz Folmer-Andersen1, Jean-Marie Lehn
1Institut de Science et d'Ingénierie Supramoléculaires, Université de Strasbourg, 8 Allée Gaspard-Monge, BP 70028, 67083 Strasbourg, France.
Journal of the American Chemical Society
|June 7, 2011
まとめ
この研究では,温度とpHによって分子量を変えるナノ構造のポリマーを導入しました. このダイナミックな素材は,アダプティブなアプリケーションのための二重制御を提供します.
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
- 超分子化学 超分子化学
背景:
- アシルヒドラゾンポリマーは,可逆凝縮反応を通じて調節可能な性質を提供します.
- ナノ構造ポリマーは,高度な材料のアプリケーションに興味があります.
- ポリマーの低臨界溶液 (LCS) の行動は温度に依存しています.
研究 の 目的:
- ナノ構造のポリ (アシルヒドラゾン) の熱反応性を研究する.
- ポリマーの分子量と形態学に対するpHの影響を調査する.
- ポリマー・アセンブリのダイナミック・コントロールを特徴付けるために.
主な方法:
- ヘキサグライム基を持つナノ構造のポリ ((アシルヒドラゾン) の合成.
- トルビドメトリーを用いた低臨界解 (LCS) 行動分析.
- サイズ除外クロマトグラフィー多角レーザー光散射 (SEC-MALLS) による分子量決定.
- 伝送電子顕微鏡 (TEM) を使用した形態学的特徴付け.
主要な成果:
- ポリマーは,酸性条件下での温度とともに反転可能な分子量増加を示します.
- ポリマーの成長はLCS温度を下回り,ナノ構造を保ちます.
- LCS温度より上では,マイクロフェーズ分離により,束や繊維に集積する.
- 中性またはアルカリ条件下では,分子量の変動は観察されなかった.
結論:
- 観察されたポリマーの成長は,アシルヒドラゾン結合ではなく,熱反応性ヘキサグライム群に起因する.
- このシステムは,温度とpHによってポリマー状態の二重制御を実証しています.
- これは,適応能力を持つダイナミックな材料のプロトタイプを表しています.
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