単一のポリステリンの鎖でπ-πの積み重ねによる力による移行
Wanhao Cai1, Duo Xu2, Lu Qian1
1Key Laboratory of Advanced Technologies of Materials (Ministry of Education), Southwest Jiaotong University , Chengdu 610031 , China.
Journal of the American Chemical Society
|June 11, 2019
まとめ
大分子 π-π 相互作用を定量化することは困難です. この研究では,ポリステリンの
科学分野:
- ポリマー科学
- 超分子化学
- 材料科学
背景:
- π-π相互作用は分子認識と自己組織化において極めて重要です.
- ポリスチレン (PS) のようなマクロ分子内のπ-π相互作用の強さを定量化することは困難です.
- これらの相互作用を理解することは 新しい素材をデザインする上で重要です
研究 の 目的:
- ポリステリンの鎖内π-π相互作用の強さを定量化する.
- 単一ポリステロールチェーンにおける π-π スタッキングの種類と振る舞いを調査する.
- 小分子システムとのPS π-π相互作用を比較する.
主な方法:
- 単分子原子力顕微鏡 (AFM) が使われました.
- 誘導分子動力学 (SMD) のシミュレーションを用いた.
- 実験は高真空状態で行われた.
主要な成果:
- ポリスチレンの鎖内π-π相互作用強度は0. 7 kcal/molと推定された.
- この値は,小分子システム (例えばベンゼンダイマー) で観測された値より著しく低い.
- 単一のPSチェーンで2種類のπ-πスタッキングが識別された:every-other-moiety (E型) と隣接するmoiety (A型).
- フォースストレッチは,E型からA型π-πスタッキングへの移行を誘導した.
結論:
- この研究は,ポリステリンのπ-π相互作用の定量的な測定値を提供します.
- ポリスチレンは,小分子とポリエチレンと比較して異なる π-π スタッキング行動を示す.
- 力による π-π スタッキングの観測された移行は,ポリマーの力学と材料特性に影響を及ぼします.
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