二重ブロックコポリマー溶液の熱処理は,金属工学を模倣する
Kyungtae Kim1, Morgan W Schulze1, Akash Arora1
1Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455-0132, USA.
Science (New York, N.Y.)
|May 6, 2017
まとめ
ポリ (イソプレン) - ポリ (ラクチド) ディブロック共ポリマーの熱的経歴は,それらの最終構造を決定する. 特定の冷却方法は,金属合金ラベス相を含むユニークな結晶または準結晶状態につながる可能性があります.
科学分野:
- ポリマー科学
- 材料科学
- クリスタルグラフィー
背景:
- ポリマーの自己組み立ては 先進的な材料にとって極めて重要です
- ポリマーの形態学への処理の影響を理解することは鍵です.
- 低モラー質量ディブロックコポリマーには調節性がある.
研究 の 目的:
- ポリ・イソプレン・b・ポリ・ラクチド・ディブロック・コポリマー形態に及ぼす熱史の影響を調査する.
- 結晶状態と準結晶状態の形成を研究する
- 構造開発における冷却速度と冷却の役割を明らかにする.
主な方法:
- 小角X線散射 (SAXS) 実験について
- 制御された冷却と消火プロトコル
- 自己一貫した平均場理論 (SCMF) の計算.
主要な成果:
- コポリマー自己組み立てで観測された例外的な熱歴依存性.
- 直接冷却によって 記録された形状が生まれます
- 熱を伴う急速な冷却は,六角形C14と立方形C15のラヴスフェーズを形成する.
- フランク・カスパー・フェーズには アクセシブルで ほぼ変性自由エネルギーがある
結論:
- 処理履歴は,これらのコポリマーにおけるメタステーブル状態の決定的な決定因子です.
- 分散体積と多面形の自己組み立て粒子が形成されます.
- この発見は,熱処理による複雑なポリマー構造の設計に関する洞察を提供します.
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