超分子ポリマーにおけるチェーン長さの光動的制御:インターカレーターをチェーンキャッパーに切り替える
Elisabeth Weyandt1,2, Gijs M Ter Huurne1,2, Ghislaine Vantomme1,2
1Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
Journal of the American Chemical Society
|March 14, 2020
まとめ
研究者は,超分子ポリマー長さを制御するために光反応性モノマーを開発しました. これらのモノメアは,インターカレーからキャピングに切り替え,ポリマー鎖を逆転的に短くし,ゲルからソルへの相変化を誘導する.
科学分野:
- 超分子化学
- ポリマー科学
- 材料科学
背景:
- 超分子システムはダイナミックな性質を備えているが,共ポリマー化には正確な制御が必要である.
- ポリマーの長さ,組成,配列,形状を制御することは,高度なアプリケーションに不可欠です.
研究 の 目的:
- 制御された超分子共ポリマー化のための光反応性モノマーを設計する.
- 光刺激を用いてポリマー鎖の長さと形状を動的に制御する.
主な方法:
- 光反応性モノアシルヒドラゾン機能化されたベンゼン-1,3,5-トリカルボキシアミド (m-BTA) モノマーの合成.
- m-BTAとアキラルアルキルBTA (a-BTA) の共同組み立て
- 光学スペクトロスコーピー,光散乱実験,理論モデル.
主要な成果:
- チラルのm-BTAモノメアは,E同位体でヘリックスキラリティを決定し,Z同位体ではチェーンキャッパーとして作用する.
- m-BTAのフォトイソメリゼーションは,高分子積層におけるポリマー鎖の長さを可逆的に減少させる.
- 質量バランスの熱力学モデルは,コポリマーの組成と長さの分布を正確に予測しました.
- ほとんどのオルガンゲルの惰性性にもかかわらず,光による鎖の短縮により,ゲルから溶液への相変換が観察されました.
結論:
- 刺激に反応するコモノーマーは,惰性ポリマーシステムで効果を拡大することができる.
- ポリマーの長さの光制御は,ダイナミックなチェーン短縮で達成できます.
- このアプローチは,超分子材料におけるマクロスコーピック相変換の方法を提供します.
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