マルチグラムスケールでトポケミカル [2 + 2] サイクル添加によって合成された二次元ポリマー
Ralph Z Lange1, Gregor Hofer1, Thomas Weber1
1Institute of Polymers and ‡X-ray Platform, Department of Materials, Swiss Federal Institute of Technology, ETH Zürich , Vladimir Prelog-Weg 5, 8093 Zürich, Switzerland.
Journal of the American Chemical Society
|January 14, 2017
まとめ
研究者は,2Dポリマーの最初の単結晶対単結晶 (scsc) 合成を [2+2]-cycloadditionを用いて報告した. この新しい方法は,高度な材料の用途に適した高品質の2Dポリマーシートを生成します.
科学分野:
- 材料科学
- ポリマー化学
- クリスタルグラフィー
背景:
- シングル・クリスタル・トゥ・シングル・クリスタル (scsc) 合成は,材料構造に対する正確な制御を提供します.
- 二次元 (2D) ポリマーは,ユニークな電子および機械的性質を持つ材料のクラスです.
- 光化学的に誘発された [2+2]-サイクル添加は,ポリマー合成のための多用途反応である.
研究 の 目的:
- 光化学的に誘発された [2+2]-cycloadditionによる2Dポリマーの最初のscsc合成を報告する.
- 高品質の2Dポリマー単体結晶の形成を実証する.
- 2Dポリマーの構造と性質を記述する.
主な方法:
- モノマーとポリマーの分析のための単結晶X線 difraktion.
- ポリメリゼーションのための光化学 [2+2]-サイクル添加反応.
- ポリマー結晶の湿った剥離
- 層の高さを決定するための原子力顕微鏡 (AFM).
主要な成果:
- [2+2]-サイクロアディションに基づく最初のscsc二次元ポリメリゼーションを達成した.
- 2Dポリマー単体結晶への定量変換が得られた.
- AFM高さ ~1.2 nmと ~2.2 nmの単層と二層を成功裏に剥がした.
- 高分子量 (360 MDa) と高分子化度 (464,900 per μm2) を決定した.
- 5 × 5 μm2までの2Dポリマーシート.
結論:
- この研究は, [2+2]-サイクロアディションを用いた2Dポリマーの画期的なscsc合成を提示しています.
- この方法により,高品質で広い2Dポリマー材料が得られます.
- 開発された技術は,高度な2Dポリマーベースの材料の設計と製造のための新しい道を開きます.
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