液晶溶媒における結合ポリマーの鎖長に依存したネマティック・オーダーリング
Alexei Tcherniak1, David Solis, Saumyakanti Khatua
1Department of Chemistry, Rice University, Houston, Texas 77005, USA.
Journal of the American Chemical Society
|August 20, 2008
まとめ
液晶中のポリマーの順序パラメータは,分子量の増加とともに減少します. より大きなポリマーチェーンには,より多くの欠陥があり,液晶溶媒内の配列を制限します.
科学分野:
- マテリアルサイエンス 材料科学
- ポリマーサイエンスの科学
- 物理化学 物理化学
背景:
- 液晶は,独特の光学および電気的特性を有するアニゾトロプ的流体である.
- ポリマー溶液は,液体結晶相に影響を与え,並べることができます.
- 溶液と溶媒の相互作用を理解することは,先進的な材料の開発に不可欠です.
研究 の 目的:
- 液体結晶溶媒におけるポリマーの分子量とその順序パラメータとの関係を調査する.
- 4-シアノ-4-n-ペンチルビフェニル (5CB) に含まれるポリ[2-メトキシ-5-(2'-エチルヘキシロキシ) -1,4-フェニレンビニレン] (MEH-PPV) の配列を定量化する.
主な方法:
- アンサンブル吸収極化スペクトロスコーピーを利用しました.
- 単一分子の光極化測定を用いた.
- 5CB.におけるポリマー鎖の長さの関数としてMEH-PPVの順序パラメータを決定した.
主要な成果:
- 溶質の分子量に対する溶質順序パラメータの明確な依存性を示した.
- 5CB液晶の中で,MEH-PPVの大規模なオーダーリングが観察されました.
- アンサンブルおよび単一分子のスペクトロスコピー技術との間で良好な一致性が見つかりました.
結論:
- ポリマーの分子量が増えると,欠陥が多くなる.
- これらの欠陥は,より大きなポリマー溶液の配列の程度を本質的に制限します.
- この発見は,液体結晶媒体におけるポリマーの振る舞いに関する洞察を提供します.
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