二極結合による二極聚合によるビス・メロシアニン染料の超分子ポリメリゼーションとゲル形成
Sheng Yao1, Uwe Beginn, Tobias Gress
1Institut für Organische Chemie, Universität Würzburg, Am Hubland, D-97070 Würzburg, Germany.
Journal of the American Chemical Society
|July 1, 2004
まとめ
2つのメロシアニン染料は,結合によって上分子ポリマーを形成します. これらのポリマーは溶媒に依存する振る舞いを示し,凝結につながり,材料科学における潜在的な応用を持つ硬い棒状の組成を形成します.
科学分野:
- 超分子化学 超分子化学
- マテリアルサイエンス 材料科学
- ポリマー化学のポリマー化学について
背景:
- メロシアニン染料は,自己組織化の可能性のある高二極性分子です.
- 固いリンクは,制御された超分子ポリメリゼーションのために分子を事前に組織することができます.
- 集積の振る舞いを理解することは,新しい材料を設計する鍵です.
研究 の 目的:
- 縛られたメロシアニン染料の超分子ポリメリゼーションを調査する.
- 形成された様々なタイプの染料集積物を特徴付けるために.
- 結果となる超分子組成物の構造的およびレオ学的性質を明らかにする.
主な方法:
- 染料の集積と溶媒効果をモニターするためのUV/visスペクトロスコーピー.
- 溶液の性質と凝固を研究するために,粘度計とリオロジーを用いる.
- 構造分析のための原子力顕微鏡 (AFM) と冷凍伝送電子顕微鏡 (cryo-TEM).
- 固体構造を調査するためのX線 difraktion.
主要な成果:
- モノメア染料とD型およびH型集積物の溶媒依存の均衡が観察されました.
- H-アグレガートは高固有の粘度を示し,マクロ分子行動を示す.
- 凝縮は,アルキル鎖の絡み合いのため,より高い濃度で発生します.
- AFM,冷凍TEM,X線 difraktionでは,柱状メソモルフィズムを持つ長い,硬い,棒状の超分子組成を明らかにしています.
- 構造モデルは,管状の染料集積で5nm直径の棒を形成する6つの交絡した糸を提案しています.
結論:
- 縛られたメロシアニン染料は,分子間集積を通じて超分子ポリメリゼーションを受けることができます.
- D-およびH-アグレガートの形成は溶媒に依存し,異なる組立型の形成につながります.
- 超分子ポリマーは,凝固に起因する絡み合ったネットワークを形成し,液体結晶の性質を示します.
- 詳細な構造モデルは,異地化されたエキストン状態を持つ硬い棒状の集合体の形成を説明しています.
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