温度感受性共ポリマーを用いた非均衡組成の基本原理の調査
Supraja S Chittari1, Allie C Obermeyer2, Abigail S Knight1
1Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States.
Journal of the American Chemical Society
|March 13, 2023
まとめ
合成ポリマーは熱ヒステリシスを示し,組成と加熱/冷却速度に影響される非均衡の振る舞いを示します. この研究は,これらの要因を調整した材料設計に操作することによって,ポリマーの性質を制御する方法を示しています.
科学分野:
- 柔らかい物質の物理学
- ポリマー科学
- 材料化学
背景:
- 複雑なエネルギー環境は,自然材料と合成材料の両方の構造と機能の関係と環境の感受性に不可欠です.
- 非均衡のダイナミクスを理解することは 先進的な材料でこれらの振る舞いを活用するための設計原理の開発の鍵です
研究 の 目的:
- 熱反応性ポリマーの非均衡の熱ヒステリック行動に対する組成と刺激経路の影響を調査する.
- ペンデントサイドチェーンの長さ,水性,および温度ランプの速度がポリエチレングリコール基コポリマーにおけるヒステレスにどのように影響するかを調査する.
主な方法:
- 熱的ヒステリックな振る舞いを観察するために,タービドメトリー分析を使用した.
- ヒステレシスを定量化するために,重複しない熱冷却サイクルを実行した.
- コポリマー組成 (サイドチェーンの長さ,水害性) と温度上昇率を体系的に変化させた.
主要な成果:
- 熱反応性低臨界溶液温度 (LCST) コポリマーでは,有意な熱ヒステレスが発生する.
- ヒステレシスは,コポリマー組成,特に懸垂側鎖の長さおよび水害性に依存していることが実証されています.
- 温度上昇率はヒステリシスに重大な影響を及ぼし,特定のプロトコルの下で不溶性状態の動的トラップを可能にします.
結論:
- 軟合成材料のバランスの外効果を活用するための基本原則を確立した.
- LCSTコポリマーの非均衡熱ヒステレスが組成と熱処理によって調節可能であることを実証した.
- 予測可能な環境への反応性を持つスマート素材を設計するための基礎を提供します.
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