狭帯間結合ポリマーのルイス酸添加物
Gregory C Welch1, Guillermo C Bazan
1Center for Polymers and Organic Solids, Department of Chemistry and Biochemistry, The University of California, Santa Barbara, California 93106, USA.
Journal of the American Chemical Society
|March 8, 2011
まとめ
ルイス酸は結合コポリマーと相互作用し,改変された受容体単位が結合を強化します. この戦略により,新しい近赤外線を吸収するポリマーが作られ,帯域のギャップを調整することができる.
科学分野:
- マテリアルサイエンス 材料科学
- オーガニック・エレクトロニクス
- フォトケミストリー フォトケミストリー
背景:
- ドナー・ユニットとアクセプター・ユニットを持つ結合コポリマーは,有機エレクトロニクスにとって極めて重要です.
- ルイス酸の相互作用は,これらの材料の電子特性を調節することができます.
- ベンゾ[2,1,3]チアジアゾール (BT) 単位におけるステリック阻害は,ルイス酸の結合に影響する.
研究 の 目的:
- ルイス酸と狭帯のギャップ結合コポリマーとの相互作用を調査する.
- アクセプターユニットの構造的変化がルイス酸の協調にどのように影響するかを理解する.
- ルイス酸結合による新しい近赤外線 (NIR) 吸収ポリマーの作成を調査する.
主な方法:
- モデル化合物とポリマーシステムの合成と特徴付け.
- 紫外線光放出スペクトロスコーピー (UPS) を含むスペクトロスコーピーの研究.
- 電子構造の変化を分析するための密度関数理論 (DFT) 計算.
主要な成果:
- ポリマー1は,小分子と比較して,Bとより弱い結合を示した.これは,BTの窒素部位の周りのステリック障害によるものである.
- ピリダル[2,1,3]チアジアゾール (PT) をより基本的な窒素部位と併用することで,ルイス酸の結合が強化された.
- 新しいNIR吸収ポリマーが生成され,バンドギャップはB (C) (6) F (5)) (3) の結合で1.31から0.89eVまで調節可能となった.
- PTへのボラン調整は,HOMOとLUMOの両方を低下させ,LUMOのより大きな減少により,バンドギャップを狭めました.
結論:
- BT単位におけるステリック阻害は,結合コポリマーにおけるルイス酸調整を低下させる.
- PTのようなより基本的な窒素部位を持つ受容体ユニットを設計すると,ルイス酸の相互作用が強化されます.
- ルイス酸結合は,先進的な電子アプリケーションのための調整可能なバンドギャップを持つNIR吸収ポリマーを設計するための実行可能な経路を提供します.
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