アニゾトロプ的熱膨張と形状記憶効果が先行する一次元調整ポリマーの可逆熱塩化
Bibhuti Bhusan Rath1, Gianpiero Gallo2,3, Robert E Dinnebier2
1Department of Chemistry, National University of Singapore, Singapore 117543.
Journal of the American Chemical Society
|January 21, 2021
まとめ
この研究は,一次元調整ポリマー (CP) で新しい可逆熱塩素 (TS) 効果を明らかにしています. この材料は独特の熱反応性と形状記憶性を表しており,多循環アクチュエータの有望な候補となっています.
科学分野:
- 材料科学
- クリスタルグラフィー
- 化学について
背景:
- 熱に反応する結晶は,高度なアクチュエーション材料の開発の鍵です.
- 調整ポリマー (CP) で珍しい現象である熱塩素 (TS) 効果は,エネルギー伝導の可能性を提供します.
- CPにおける可逆性TS効果は,特に実用的なアプリケーションにおいて望ましい.
研究 の 目的:
- 1D CPにおける可逆性TS効果の発見と特徴を報告する.
- 逆転性TS効果と関連する熱的行動の根本的なメカニズムを調査する.
- マルチサイクルアクチュエータとしてのこのCPの可能性を評価する.
主な方法:
- 新しい1D協調ポリマーの合成と特徴付け
- 微分スキャニングカロメトリー (DSC) を用いた熱的性質の調査
- 段階移行と熱膨張の分析
主要な成果:
- 1D CPでは,マーテンシット・フェーズ・トランジションに関連した加熱・冷却サイクルにおいて,可逆的な熱塩素 (TS) 効果が観察された.
- 材料はTS効果の前に有意なアニゾトロプ的熱膨張を示した.
- 非分子結晶は反転可能な収縮と回復を示し,複数のサイクルで自己修復形状記憶効果を示しています.
結論:
- 1D CPは,マーテンシト的相変化によって駆動されるユニークな,可逆的なTS効果と形状記憶行動を示します.
- この材料が20回以上の反転式アクチュエーションサイクルを経験する能力は,マルチサイクルアクチュエーターとしての可能性を強調しています.
- この発見は金属-有機物質の 熱反応に関する新しい行動を示しています
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