ダイナミックな微溶液における方向性超分子ポリメリゼーション: 線形的に動くポリマーの末端に衝突するモノマー
Shota Matoba1, Chisako Kanzaki1, Kae Yamashita1
1Department of Biomolecular Chemistry, Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Shimogamo, Sakyo-ku, Kyoto 606-8522, Japan.
Journal of the American Chemical Society
|June 1, 2021
まとめ
研究者は,ペリレンビシミド (PBI) モノマーを用いた方向性超分子ポリメリゼーションの方法を開発した. マイクロフローチャネルでの切断力は,成長するポリマーの片端を選択的に活性化し,制御された成長とブロックコポリマー合成を可能にします.
科学分野:
- 超分子化学
- 材料科学
- ポリマー化学
背景:
- 方向性連鎖反応は自然界では一般的ですが 人工自己組織化では難しいものです
- 既存の人工的な一次元自己組み立てシステムには制御された方向性のある成長がない.
研究 の 目的:
- ペリレンビシミド (PBI) デリバティブを用いた方向性高分子ポリメリゼーションのシステムを開発する.
- ポリマーの成長を制御し,ブロックコポリマーの合成を可能にすることにおける切断力の役割を調査する.
主な方法:
- マイクロフローチャネルシステムでモノマーとして利用されたペリレンビシミド (PBI) デリバティブ.
- 変化する流れ率と切断ストレス下で核化と成長のダイナミクスを調査した.
- 立体光スペクトルと線形二重化を用いてポリメリゼーションをモニターする.
- この戦略を二重ブロックコポリマー形成のための二重モノマーシステムに適用した.
主要な成果:
- PBIモノメアの自発的な核形成が誘発され,剪定力によって促進されました.
- シェアストレスは,指向型ポリマーの片端で選択的にポリマーの成長を加速した.
- 自由モノメア核化よりも方向性のある成長が優勢だった.
- 二重ブロック共ポリマーがポリマーの末端で選択反応によって成功して合成され,分子ヘテロジャンクションを形成した.
結論:
- 単一のポリマー端の摩擦誘発による活性化により,方向性のある超分子ポリメリゼーションが可能になる.
- この戦略は,指向的な超分子ブロック共ポリメリゼーションに広く適用できます.
- ポリマーの分子ヘテロ結合の正確な形成を可能にします.
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