液晶のオクトープス・デンドリマー:異様なメソフェーズ形態を持つブロック分子

Lionel Gehringer¹, Cyril Bourgogne, Daniel Guillon

¹Institut de Physique et Chimie des Matériaux de Strasbourg - IPCMS, Groupe des Matériaux Organiques - GMO, UMR 7504 - CNRS/Université Louis Pasteur, 23, rue du Loess, BP 43, F-67034 Strasbourg Cedex 2, France.

Journal of the American Chemical Society

|March 25, 2004

まとめ

独特の分岐構造を持つ新しいオクトープス・デンドリマーは,新しい液晶相を示しています. 彼らのメソフェーズの行動は分子構造に依存し,高度な材料の構造-特性関係に関する洞察を提供します.

科学分野:

材料科学材料科学とは
有機化学オーガニック・ケミストリー
ポリマーサイエンスの科学

背景:

古典的な液晶型デンドリマーは,通常,エンド機能化されています.
以前の研究は,同一の構成要素を持つホモリシック・デンドリット系に焦点を当てていた.

研究の目的:

新型主鎖液晶型デンドリマー (オクトパス型デンドリマー) を合成し,特徴づけること.
これらの新しいデンドリート系,特にヘテロリート系におけるメソモルフィック性質を調査する.

主な方法:

dendritic 枝と dendrimers のモジュール合成.
ポラライズされた光学顕微鏡.
X線 difrraction研究 (小さなブラッグ角を含む).
分子モデライゼーション.

主要な成果:

独特の樹木形成を持つ新種のヘテロリシックオクトープス・デンドリマーの合成が成功しました.
新しい形状を持つスメクティック状および柱状の液晶相の観察.
メソフェーズの種類と安定性は,端末鎖とメソゲンセグメントの数と配置に依存しています.

結論:

オクトパス・デンドリマーは,古典的なシステムと比較して,異なったメソモルフィックな性質を示しています.
メソゲンセグメントの性質と空間的位置を含む分子構造は,メソフェーズ行動に決定的な影響を及ぼします.
スメクティック・フェーズとコラムナー・フェーズにおける分子組織のモデルを提案した.

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