原子移転基質ポリメリゼーションの均衡定数の決定
Wei Tang1, Nicolay V Tsarevsky, Krzysztof Matyjaszewski
1Center for Macromolecular Engineering, Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, USA.
Journal of the American Chemical Society
|February 2, 2006
まとめ
修正されたフィッシャー
科学分野:
- ポリマー化学のポリマー化学について
- 物理化学 物理化学
- 有機化学 オーガニック・ケミストリー
背景:
- 原子移転ラジカルポリメリゼーション (ATRP) は,活性種と休眠種間の均衡に依存しています.
- ATRP均衡定数 (K ((ATRP)) の正確な決定は,ポリメリゼーションの制御に不可欠です.
- フィッシャー方程式を使用する既存の方法は,低変換とK ((ATRP)) 値に限定されています.
研究 の 目的:
- より高い変換で K ((ATRP) を決定するための修正されたフィッシャー方程式を開発し,検証する.
- 様々な触媒およびアルキルハリドのK (ATRP) を正確に測定するために.
- ATRPにおける構造-反応性の関係を調査する.
主な方法:
- 修正されたフィッシャー方程式で,触媒とイニシアター濃度の変化を考慮した.
- 新しい方程式を検証するための運動シミュレーション.
- 銅種 (X-Cu(II)).をモニターするためのUV-visスペクトロメトリ.
- ガスクロマトグラフィー (GC) は,イニシアター濃度を追跡する.
主要な成果:
- 修正された方程式は,変換>10%でK(ATRP) と>10(-7でK(ATRP) を正確に決定します.
- 複数の触媒/アルキルハリド系におけるK (((ATRP)) 値の決定に成功しました.
- ATRPコンポーネントの反応性に対する構造的変動の影響を実証した.
結論:
- 修正されたフィッシャー方程式は,ATRPにおける均衡定数の決定の適用性を拡張します.
- 正確な K (((ATRP) 値は,ポリメリゼーションプロセスを正確に制御するために不可欠です.
- 構造と反応性の関係を理解することは,効率的なATRPシステムを設計するのに役立ちます.
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