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エントロピー駆動型環開きメタテシスによる配列制御ポリマー:理論,分子量制御,およびモノマー設計
Jamie A Nowalk1, Cheng Fang1,2, Amy L Short1
1Department of Chemistry , University of Pittsburgh , Pittsburgh , Pennsylvania 15260 , United States.
Journal of the American Chemical Society
|February 5, 2019
まとめ
配列化されたポリエステルの合成は,選択性強化リング開きメタテシスポリメリゼーション (SEED-ROMP) を使用して,現在スケーラブルで制御可能です. この方法は,分子量とポリマーの性質を正確に制御し,以前の制限を克服します.
科学分野:
- ポリマー化学
- 材料科学
背景:
- モノマー配列はコポリマー特性に重大な影響を及ぼしますが,配列化されたコポリマーの制御された合成は困難です.
- 以前の段階的成長方法では,分子量制御,スケーラビリティ,および収穫の予測性が欠けていました.
研究 の 目的:
- シーケンス化されたポリエステルを合成するための効率的でスケーラブルで制御可能な方法を開発する.
- 新しいポリメリゼーション技術を用いて,モノマー配列のポリマー特性への影響を調査する.
主な方法:
- サイクルマクロモノマーのエントロピー駆動型リング開きメタテシスポリメリゼーション (ED-ROMP) による配列化されたポリエステルの合成.
- ED-ROMPのためのエチレングリコールとメタテシスリンク器の組み込み
- 環閉メタテシスとマクロラクトニゼーションを用いたサイクルマクロモノマーの製造.
- 選択性強化 (SEED-ROMP) のメタテシス活性セグメントにおけるシスオレフィンを使用する.
主要な成果:
- 制御された分子量で配列化されたポリエステルのマルチグラムスケール合成
- SEED-ROMPは第一級の運動性と狭い分散性を示し, 強化された生活特性を示した.
- ブロックコポリマーの準備が成功し,ポリメリゼーションの生きた性質をさらに確認しました.
- 計算分析により,シスマクロサイクルのオレフィンは,形状的な好みにより,ポリメリゼーション運動性を高めることが明らかになった.
結論:
- SEED-ROMPは,精密に組み込まれた配列セグメントを持つ分子量制御されたポリマーを生産するための一般的で効果的な戦略を提供します.
- この進歩は,以前の方法の限界を克服し,ポリマー科学におけるより広範な応用を可能にします.
- この発見は制御されたシーケンスを通して 量身の固体特性を有するポリマーを 設計するための道を切り開きます
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