三脚のビルディングブロックを使用して巨大なデンドリマーの建設
Jaime Ruiz1, Gustavo Lafuente, Sylvia Marcen
1Laboratoire de Chimie Organique et Organométallique, UMR CNRS No. 5802, Université Bordeaux I, 33405 Talence Cedex, France.
Journal of the American Chemical Society
|June 12, 2003
まとめ
巨大なオルゴン・シリコン・デンドリマーは,新しい異なる方法を使用して,第9世代まで合成されました. これらの高度に枝分かれした構造は,包装の限界を超えており,内部の枝の折り畳みはさらなる成長を制限する可能性があることを示唆しています.
科学分野:
- マテリアルサイエンス 材料科学
- 有機化学 オーガニック・ケミストリー
- ポリマー化学のポリマー化学について
背景:
- デンドリマーは,ユニークな性質を持つ高度に枝分かれしたマクロ分子です.
- オーガノ-シリコンデンドリマーは,高度なアプリケーションのための調整可能な特性を提供します.
- デンドリマー合成における高世代の達成は,大きな課題を提示する.
研究 の 目的:
- 巨大ペンタン溶性オルガノシリコンデンドリマーを合成する.
- 第9世代 (G(9) まで,新しい異なる建設方法を探求する.
- これらの高世代デンドリマーの構造的整合性と性質を特徴付ける.
主な方法:
- 水酸化-核愛性置換配列を用いた分散合成.
- 核磁共振 (NMR) スペクトロスコーピーを用いた反応モニタリング ((1) H, (13) C, (29) Si).
- マトリックス・アシストレーザー・デソルプション/イオニゼーション・タイム・オブ・フライト (MALDI TOF) 質量スペクトロメトリ,サイズ・エクスクルーション・クロマトグラフィ (SEC),高解像度トランスミッション電子顕微鏡 (HRTEM),原子力顕微鏡 (AFM) による特徴付け.
主要な成果:
- オーガノシリコンデンドリマーの合成が成功し,G(9) までのクリーン反応が,NMRで確認されました.
- MALDI TOFとSECは,下位世代 (G(1) -G(5) の単分散性 (1.00-1.02) を確認しました.
- HRTEMとAFMは,高世代の予想されるサイズ進行と球状の形を明らかにし,G(9) は10(5) 端末の枝を上回り,密度の高い包装の限界を超えました.
結論:
- この新しい異なるアプローチにより,非常に大きなオルガノ-シリコン dendrimersの合成が可能になります.
- G(9) のデンドリメアは,理論的な密集の限界を大幅に超えており,内部の枝が折りたたまれていることを示しています.
- イントラデントリト反応は,これらの高密度のデントリト構造のさらなる成長を制限する要因として提案されています.
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