デンドリマー型ポリエチレン酸化物のpH反応性
Xiaoshuang Feng1, Daniel Taton, Redouane Borsali
1Laboratoire de Chimie des Polymères Organiques, Ecole Nationale Supérieure de Chimie et Physique de Bordeaux-Université Bordeaux-1-CNRS 16, Avenue Pey Berland, 33607 Pessac Cedex, France.
Journal of the American Chemical Society
|August 31, 2006
まとめ
研究者らは,内部のポリアクリル酸鎖を備えたデンドリマーのようなポリエチレン酸化物 (PEO) スキャフォールドを使用して,pHに対応する単分子システムを作成しました. これらの構造は,pHの変化に伴い,反転的に縮小し,膨張し,分子内複雑化による結合を避けます.
科学分野:
- ポリマー化学のポリマー化学について
- 超分子化学 超分子化学
- マテリアルサイエンス 材料科学
背景:
- ポリエチレン酸化物 (PEO) とポリエチレン酸 (PAA) は,非共性相互作用によるpH感度アグレグレーションで知られている.
- ポリマーのアーキテクチャを制御することは,反応性のある材料を設計し,マクロスコープの集積を避けるための鍵です.
研究 の 目的:
- PEOとPAAを特定のデンドリマーのような構造に組み立てることで,pH反応性のある単分子システムを合成する.
- pH誘発の可逆的なサイズ変化のためのPAAとPEOユニット間の分子内複合性を利用する.
- 分子間複合やマクロスケープの集積を避けるために.
主な方法:
- アニオン環開きポリメリゼーション (AROP) と新しいAB(2) C分岐剤を用いた第5世代デンドリマー型のPEO構造物の合成.
- 原子移転ラジカルポリメリゼーション (ATRP) 開始部位経由で,PEO・エスカフォードの内部ビニル基をポリアクリル酸 (PAA) 鎖に機能化する.
- 動的光散乱 (DLS) を用いて,PHに依存したサイズ変動を評価するために,PAAを運ぶデンドリマー型PEOsの特徴化.
主要な成果:
- 21の内部,接合部に付着したPAAブロックを備えた水性,デンドリマー状のPEOsを成功裏に合成しました.
- 単分子系が水中で逆転的に縮小・膨張するpH反応性行動を示した.
- 特定のアーキテクチャが分子間複合を防止し,分子内相互作用を好むことが確認されました.
結論:
- 設計されたデンドリマー型のPEOアーキテクチャは,PEOとPAAチェーンの自己組み立てを効果的に制御します.
- これらの単分子系は,分子内PAA-EO複合化により,調節可能,可逆のpH反応的行動を示す.
- このアプローチは,高度な反応性ポリマー材料を作成するための新しい戦略を提供します.
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