設計,合成,および,調整された移植配分を持つポリマーの自己組み立て
Alice B Chang1, Tzu-Pin Lin1, Niklas B Thompson1
1Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena, California 91125, United States.
Journal of the American Chemical Society
|November 9, 2017
まとめ
この研究では,リング開きメタテシスのポリメリゼーションを用いて制御された構造を持つポリマーを合成するための新しい方法を示しています. この多面的な戦略により,高度な材料の設計のために,移植分布とポリマーの性質を正確に制御できます.
科学分野:
- ポリマー化学
- 材料科学
- 有機合成
背景:
- ポリマーの接ぎ木密度と分布を正確に制御することは,材料の特性を調整するために不可欠ですが,合成の課題です.
- 現存する方法は,多くの場合,移植ポリマーの特定の建築制御を達成するための多用途性を持っていません.
研究 の 目的:
- 精密に制御されたアーキテクチャを持つ移植ポリマーを合成するための多用途戦略を開発する.
- 予測可能な配列制御のための共ポリメリゼーションを制御する運動学とメカニズムを調査する.
主な方法:
- マクロモノマーと稀解剤の単一ポット共ポリメリゼーションによる接入式環開封メタテシスポリメリゼーション (ROMP) を採用した.
- 構造-反応性の関係を理解するために,様々な稀剤の同ポリメリゼーション運動を研究した.
- 交叉伝播速度の定数と反応率を決定するためにマヨ・ルイス末端モデルを適用した.
- 小角X線散射 (SAXS) を使用して,自己組み立て構造を分析し,移植分布と相関する.
主要な成果:
- 調節可能なホモポリメリゼーション率 (0.3682 M-1 s-1) を稀釋剤改変により実証した.
- ブロック,グラデント,またはランダムなバックボーン配列を可能にする,広範囲のマクロノモナー/稀釋剤反応率 (0.0820) を達成した.
- 制御された分子形状 (角形,均一,逆角形) を有する合成されたAB移植二ブロックポリマー.
- SAXSによる自己組み立て構造に対する グラフの分布の影響を示した.
結論:
- 開発されたROMP戦略は,任意のアーキテクチャを持つ移植ポリマーの設計と合成のための一般的なアプローチを提供します.
- ROMPの動力学とモノメアの設計に関する洞察は,分子と材料の設計の可能性を広げます.
- 制御されたコポリメリゼーションは,正確な建築制御を通じてポリマーの特性を調整するための強力なツールを提供します.
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