オリゴ3-ヘキシルチオフェン (3HT) の熱および構造特性n,n = 4-36
Felix Peter Vinzenz Koch1, Martin Heeney, Paul Smith
1Department of Materials, Eidgenössische Technische Hochschule (ETH) Zürich , Wolfgang-Pauli-Strasse 10, 8093 Zurich, Switzerland.
Journal of the American Chemical Society
|August 21, 2013
まとめ
オリゴ ((3-ヘキシルチオフェン) は,異なる熱特性を持つ2つの固体構造を示しています. 処理条件は,これらのポリモルフの間の変換を制御し,材料の動作に影響を与えることができます.
科学分野:
- マテリアルサイエンス 材料科学
- ポリマー化学のポリマー化学について
- 固体物理 固体物理学
背景:
- レジオレギュラーオリゴ3-ヘキシルチオフェン (3HT) は,ポリ3-ヘキシルチオフェン (P3HT) を研究するためのモデル化合物である.
- 固体構造と熱的性質を理解することは,有機電子材料の開発に不可欠です.
研究 の 目的:
- 異なる鎖長 (n=4-36) を有するオリゴ−ヘキシルチオフェンの熱および構造特性を調査する.
- 異なる固体ポリモルフとその熱力学および運動的性質を識別する.
- これらのポリモルフの間の相互変換と,P3HTとの関連性を調査する.
主な方法:
- モノディスパース,レジオレギュラーオリゴ (((3-ヘキシルチオフェン) s.の合成
- 熱分析 (融解温度,融解エンタルピー) のための差分スキャニングカロメトリー (DSC).
- 固体構造を特徴付けるためのX線 difraktion (XRD) または類似の技術.
- ポリモルフの相互変換を誘導するための制御された処理処理.
主要な成果:
- 2つの固体ポリモルフ (Form IとForm II) が特定され,ヘキシルサイドチェーンのインターディジテーションが異なる.
- 形状IIは,形状I (~298 °C) に比べて,かなり低い融解温度 (~116 °C) と,より高い融解エンタルピーを示しています.
- 熱力学的に好ましい形IIから運動的に好ましい形Iへのクロスオーバーは,n=12で発生する.
- 10 ≤ n ≤ 21 の範囲のオリゴ ((3-ヘキシルチオフェン) は,加工によってポリモルフの間で逆転的に変換することができます.
結論:
- この研究は,オリゴ3-ヘキシルチオフェンのポリモルフィズムに関する重要な洞察を明らかにし,鎖の長さと加工の影響を強調しています.
- この発見は,P3HTに関連する構造-財産関係の基本的な理解を提供します.
- 処理によるポリモルフィズム制御は,有機半導体デバイスの性能を調整する可能性を秘めています.
関連する概念動画
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Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
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