二重光電化学触媒を用いた相互変換可能な生根およびカチオンポリメリゼーション
Andrei Nikolaev1, Zhipeng Lu1, Arunavo Chakraborty1
1Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara, California 93106, United States.
Journal of the American Chemical Society
|July 27, 2021
まとめ
この研究は,制御されたポリマー合成のための二重反応触媒を導入し,より広範なモノマー範囲のための生根とカチオン性ポリメリゼーション方法のオンデマンドの切り替えを可能にします.
科学分野:
- ポリマー化学
- 有機合成
- 材料科学
背景:
- 制御されたポリマー合成には,しばしば特定の触媒が必要であり,使用可能なモノメアの範囲を制限する.
- ブロックコポリマーのような多様なポリマーアーキテクチャを達成するには,通常,複数の異なるポリメリゼーション技術が必要です.
研究 の 目的:
- 生きた基とカチオンのポリメリゼーションの両方を媒介できる単一の触媒を開発する.
- 異なる刺激を用いたポリメリゼーション経路に対する正方形の制御を実証する.
- 緩やかな条件下でブロックコポリマーを合成するための基板の範囲を拡大する.
主な方法:
- 二重光と電気反応の触媒 (10-フェニルフェノチアジン) を使った.
- オートゴーナルな光化学的刺激と 電気化学的刺激を用いて 眠っている種を活性化します
- 異なるモノマー型 (アクリラートとビニルエーテル) の連続的な組み込みを制御するための交代刺激.
主要な成果:
- リビング・ラジカルとカチオン・ポリメリゼーションの相互変換が求められる.
- ポリマーのモラー質量とブロックの組成を正確に制御することが示されています.
- 合成されたブロックコポリマーで,異なる根性および離子性ポリマー化セグメントを有する.
- プロセス全体を通して終端グループの忠誠性と低分散性を維持します.
結論:
- 単一の二重反応触媒は,異なるポリメリゼーションメカニズムを効果的に制御できます.
- オートゴーナル刺激により 複雑なポリマー構造の合成が可能になります
- このアプローチは,金属のない条件下でブロックコポリマー合成のためのモノマー基板の範囲を大幅に拡大します.
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