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グラフェンナノリボン合成のための活体無断型π拡張ポリメリゼーション
Yuuta Yano1, Nobuhiko Mitoma1,2, Kaho Matsushima1
1Graduate School of Science, Nagoya University, Nagoya, Japan.
Nature
|June 28, 2019
まとめ
グラフェンナノリボン (GNR) の合成を,幅,エッジ構造,長さを含む,新しい生体アンヌラティブπ拡張 (APEX) ポリメリゼーション技術によって正確に制御することができる. この突破は,モジュール式GNR生産とGNRブロックコポリマーの作成を可能にします.
科学分野:
- 材料科学
- ポリマー化学
- 有機化学
背景:
- 導電性と電荷の移動性などのグラフェンナノリボン (GNR) の性質は,幅,長さ,エッジ構造に大きく依存しています.
- 現在のボトムアップ合成方法は,これらの重要なGNRパラメータ,特にステップ成長ポリメリゼーションの制限による長さを同時に制御するために苦労しています.
研究 の 目的:
- 幅,エッジ構造,長さを同時に制御するGNRを合成するための新しいポリメリゼーション技術を開発する.
- GNRとGNRブロックコポリマーの迅速かつモジュラーな合成を可能にします.
主な方法:
- ベンゾナフトシロールモノマーを用いた活体無断型π拡張 (APEX) ポリメリゼーションが採用された.
- ポリメリゼーションは,オクロラニルの存在でパラジウム/銀塩によって触媒され,フェナントレンまたはディフェニラセチレンによって開始された.
- GNRの長さを制御するには,イニシアターとモノメアの比率を調整した.
主要な成果:
- APEX技術は,制御された寸法とエッジ構造を持つフィヨルド型のGNRを成功裏に合成しました.
- この方法は,イニシアター濃度を変化させることで,GNRの長さを正確に制御することを示した.
- GNRブロックコポリマーの合成が達成され,APEXメソッドのモジュール性を示した.
結論:
- 活体APEXポリメリゼーション技術は,GNR合成の重要な進歩を提供し,構造パラメータに対する前例のない制御を提供します.
- この方法は,ブロックコポリマーを含む複雑なGNRアーキテクチャのモジュール構築を容易にする.
- 直接のC−Hアリレーションと梯子ポリメリゼーションのアプローチは,機能的なGNR材料の設計のための新しい道を開きます.
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