銅超酸化物複合体の形成を通じた酸素強化原子移転基質ポリメリゼーション
Kostas Parkatzidis1, Nghia P Truong1, Richard Whitfield1
1Laboratory of Polymeric Materials, Department of Materials, ETH Zurich, Vladimir-Prelog-Weg 5, Zurich 8093, Switzerland.
Journal of the American Chemical Society
|January 10, 2023
まとめ
酸素は,新しいARGET-ATRPメカニズムを通じて,超酸化物種を形成することによって,制御された根性ポリメリゼーションを意外に加速します. この方法はポリメリゼーション率を高め,不純な触媒でも優れた制御を持つ高分子量ポリマーを可能にします.
科学分野:
- ポリマー化学
- カタリシス
- 材料科学
背景:
- 酸素は通常,制御された根性ポリメリゼーションを阻害し,鎖の終結と触媒の無効化につながります.
- 既存の方法は,酸素の干渉を防ぐために,高度に浄化された触媒と制御された環境を必要とします.
研究 の 目的:
- 原子移転ラジカルポリメリゼーション (ATRP) での酸素の役割を調査する.
- ポリメリゼーションの効率と制御を強化するために酸素を使用する新しいATRPメカニズムを開発する.
主な方法:
- スーパーオキシド媒介型原子移転ラジカルポリメリゼーション (ARGET-ATRP) メカニズムを使用する.
- CuBr/リガンド複合体と様々なモノマーを使用しています.
- 質量スペクトロメトリーとサイズ除外クロマトグラフィを用いてポリマーを特徴づける.
主要な成果:
- 酸素はCuBr/Lから*in situ*の反応性超酸化物種の形成を誘発し,ポリメリゼーションの速度を数倍に加速する.
- 非常に低い銅濃度 (4.5 ppm) で優れた制御 (Đ < 1.20) を有する高分子量ポリマー (DPn = 6400) を達成した.
- ブロックとマルチブロックの共ポリマーの単体合成を可能にし,ほぼ定量的な変換を可能にしました.
結論:
- スーパーオキシドARGET-ATRPメカニズムは,制御された根性ポリメリゼーションのための堅牢で効率的な方法を提供します.
- 方法論は,触媒の不純物に対して耐性があり,厳密な浄化の必要性を減らし,コストを削減します.
- このアプローチは,酸素を有益な成分として利用することによって,制御されたポリメリゼーションの範囲を拡大します.
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