ボロンエステル基のヴィトリマーは,内部ボロン-窒素調整による安定性を高めています
Xiaoting Zhang1, Shujuan Wang1, Zikang Jiang1
1School of Chemistry, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, P. R. China.
Journal of the American Chemical Society
|December 17, 2020
まとめ
新しい窒素調整サイクルボロンダイエスター (NCB) 結合は,ポリマーの水と熱に対する耐性を改善します. これらの新しい結合により 持続可能で自己回復性があり 再処理可能な ガラスの構造が作れます
科学分野:
- ポリマー化学
- 材料科学
- 有機化学
背景:
- ボロンを含むポリマーは,高度なアプリケーションにユニークな特性を提供します.
- 逆転性B-O結合を持つオルガノボロン種は,自己治癒性および再処理性ポリマーに使用されます.
- 従来のボロンエステルとボロキシンには水分解の不安定性があり,その使用が制限されています.
研究 の 目的:
- 窒素調整サイクルボロンダイエスター (NCB) 結合の水分解安定性と動的共性化学を調査する.
- 安定性と再処理性を強化したNCBリンクを基に新しい種類のガラスを開発する.
- 次世代の持続可能な材料を設計するためのNCBの連携の可能性を調査する.
主な方法:
- 活性水素とイソシアネートの反応によるNCB結合を組み込んだ新しいガラスの合成.
- NCBのリンクの安定性と交換反応を評価するための熱力学と運動学的研究.
- モデル化合物 (NCBC-X1,NCBC-X2) と,その結果生じるポリウレタン/ポリウレタン) ヴィトリマーの特性
主要な成果:
- NCBリンクは,従来のボロンエステルと比較して,水と熱に対する耐性が向上しています.
- NCBリンクを基にしたガラスは,優れた溶媒耐性と機械的性質を示している.
- 加熱後のNCB結合のトランスエステル化により,材料の修復,再処理,再利用が可能になります.
- NCBのリンクにおける内部N → Bの調整は,水解と熱の安定性を高めるのに寄与する.
結論:
- NCBリンクは,安定的かつダイナミックな共性ポリマーを作るための従来のボロンエステルの有望な代替品です.
- 開発されたNCBベースのグラミーは,調節可能な特性と延長されたライフサイクルを持つ材料を設計するための持続可能な経路を提供します.
- この研究は,水解と熱の安定性を向上させることで,持続可能なポリマーの分野を前進させるための新しい戦略を提供します.
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