鎖の構造を制御し,ヘテロ原子結合ポリマーの発光を調節するための方法として,プロトネーションおよびその後の分子内水素結合
Andrew P Monkman1, Lars-Olof Pålsson, Roger W T Higgins
1Department of Physics and the Department of Chemistry, University of Durham, South Road, Durham DH1 3LE, United Kingdom. a.p.monkman@durham.ac.uk
Journal of the American Chemical Society
|May 23, 2002
まとめ
機能性ポリマーにおけるピリジル群のプロトネーションは平面性を誘導し,π結合を拡張し,赤色シフトの光学特性を引き出します. この構造変化 (poly-2,5-pyridylene-co-1,4-[2,5-bis-2-ethylhexyloxy) ]phenylene) は,光電子機器のチューニングの鍵となっている.
科学分野:
- 有機化学 オーガニック・ケミストリー
- マテリアルサイエンス 材料科学
- スペクトル顕微鏡検査です.
背景:
- プロトネーションは分子やポリマーの性質に大きく影響する.
- 構造の変化を理解することは,光電子材料のチューニングに不可欠です.
研究 の 目的:
- 特定の有機分子とその対応するポリマーの構造的およびスペクトル学的特性に対するプロトネーションの影響を調査する.
- プロトネーションが分子平面性およびπ結合に影響を与えるメカニズムを解明する.
主な方法:
- 1,4-ジメトキシ-2,5-ビス (((2-ピリジル)) ベンゼンのプロトン化および非プロトン化形態のX線結晶分析.
- 酸性条件下で分子とポリマーポリー ((2,5-ピリジレン-コ-1,4-[2,5-ビス ((2-エチルヘキシロキシ) ]フェニレン) の光譜分析 (光学吸収と放出).
- ポリマーベースのデバイスの電気発光研究.
主要な成果:
- 1,4-ジメトキシ-2,5-ビス (((2-ピリジル)) ベンゼンをテトラフルオロボリック酸でプロトン化すると,重要な分子内水素結合を持つ二酸化塩が生み出され,近平面化を引き起こす.
- 平面化分子と陽子化ポリマーは,光学吸収と放射スペクトルの大きな赤色シフトを示します.
- 溶液および膜中のポリマーのプロトネーションは,同様のスペクトルの赤色シフトを誘導し,プロトネーションされた場所とプロトネーションされていない場所の両方から発生する放射が発生します.
結論:
- プロトネーションは,分子内水素結合と組み合わせて,ポリマーをほぼ平面形状に駆り立て,π結合を拡張します.
- このメカニズムは,結合ポリマーの吸収と放出プロフィールを調整するための新しい経路を提供します.
- プロトネーションによって誘発されるスペクトルの赤色シフトは,ポリマーベースの電光発光装置でも観察されています.
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