超分子ポリマーポリモルフィズム:水素結合 π-ロゼットの脱位による自発的なヘリックス-ヘリコイド移行
Chie Otsuka1, Sho Takahashi1, Atsushi Isobe1
1Division of Advanced Science and Engineering, Graduate School of Science and Engineering, Chiba University, Chiba 263-8522, Japan.
Journal of the American Chemical Society
|October 5, 2023
まとめ
研究者らは,同一のディスク性モノマーから 2 つの超分子ポリマーポリマーを発見しました. これらのポリモルフは,異なる積み重ねの配置を示し,超分子ポリマーのユニークな螺旋構造と螺旋状の折りたたみにつながります.
科学分野:
- 超分子化学
- ポリマー科学
- 材料科学
背景:
- ポリモルフィズムにより,同一の分子が異なる自己組み立て構造を形成できます.
- 超分子ポリマーは通常,異なる次元を持つポリモルフィズムを示します.
- 一次元の超分子ポリマーの ポリモルフィズムを達成することは 難しいことです
研究 の 目的:
- 超分子ポリマーポリモルフィズムの現象を調査し,一次元集積を維持する.
- ディスコティック・スーパモレキュラー・モノマーから 異なるポリモルフの形成を調査する.
- これらのポリモルフの構造と光学的性質を理解する.
主な方法:
- 拡張されたπ結合コアを持つ大きなディスク性上分子単体 (ローゼット) の合成.
- クロロフォーム/メチルサイクロヘキサン混合物における超分子ポリマーの形成
- 光物理的性質を用いたポリモルフの特徴化.
- ディスクの積み重ねの解析 (対面対オフセット)
主要な成果:
- 同じモノマーから2つの異なる超分子ポリマーポリマーが生成された.
- ポリモルフは異なる対面とオフセットディスクの積み重ねにより生じた.
- 面対面の積み重ねにより,曲がったヘリックスが形成され,オフセットの積み重ねにより,空洞のヘリコイル (ヘリコイド) が形成された.
- ポリモルフは溶媒の組成とロゼットの脱位によって変換され,ヘリコイドの折り畳みを可能にしました.
結論:
- 超分子ポリマーポリモルフィズムが示され,一次元集積を維持しています.
- ヘリコイド構造とヘリコイド折りたたみによる 異なる積み重ねを特定した.
- モノマー解離なしの超分子ポリマーのヘリコイド折り畳みを達成するための新しい方法が提示されました.
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