液晶型ジャヌス型フルロデンドリマーで,調節可能なスメクティック・コラムナー・メソモルフィズムを示している
Julie Lenoble1, Stéphane Campidelli, Natacha Maringa
1Institut de Chimie, Université de Neuchâtel, Avenue de Bellevaux 51, Case Postale 158, 2009 Neuchâtel, Switzerland.
Journal of the American Chemical Society
|July 31, 2007
まとめ
新しいジャヌス型液晶フルロデンドリマーが合成されました. デンドロンのサイズとタイプを調整することで,スメクティックまたはコラム状の液晶相を制御することができ,C60はメソフェーズタイプに影響を与えない.
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
- 液晶は,液体クリスタルです.
背景:
- デンドリマーとフルレレンは,ユニークな性質を持つ高度な分子構造である.
- 液晶は,固体状態と同位体状態の間の秩序ある相を示す.
- これらの構造を組み合わせることで,調節性特性を有する新しい材料の可能性が生まれます.
研究 の 目的:
- ジャヌス型液晶フルロデンドリマーを合成するために.
- 液体結晶の振る舞いに対するデンドロン構造と大きさの影響を調査する.
- フルレンの核が自己組織化における役割を理解する.
主な方法:
- 合成のための1,3-二極サイクロアディション反応.
- 偏光光学顕微鏡,微分スキャニング熱計,およびX線 difraktion による特徴付け.
- 溶液の性質の測定 (二極のモメント,介電極化,ケル定数).
主要な成果:
- ジャヌス型フルロデンドリマーの合成に成功した.
- デンドリマー生成に基づくスメクティック (SmC, SmA) またはコラムナー (Colr-c2mm, Colr-p2gg) メソモルフィズムを達成した.
- デンドロンサイズ,マイクロセグレゲーション,コア変形,二極相互作用によって影響される超分子組織.
- C60コアは,形成されたメソファースの種類を変えない.
- 溶液中の微分離が観察されました.
結論:
- フラーロデンドリマーの液晶性質は,デンドロンの選択とサイズを通して設計によって正確に制御できます.
- フルレンの分子はメソフェーズ型を決定するものではなく,全体的な構造に寄与する.
- この発見は,複雑な超分子組成の構造-性質関係についての洞察を提供します.
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