CO2とエポキシドの金属無交代共聚化: "グリーン"合成と活性を実現する
Dongyue Zhang1, Senthil K Boopathi1, Nikos Hadjichristidis1
1Physical Sciences and Engineering Division and ‡KAUST Catalysis Center, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955, Saudi Arabia.
Journal of the American Chemical Society
|August 17, 2016
まとめ
メタルフリーアニオンコポリメリゼーションにより,エポキシドとCO2からポリカーボネートを成功裏に合成した. この新しい方法は,過渡金属や合成後の浄化なしで明確に定義されたポリマーを生成します.
科学分野:
- ポリマー化学
- 器官触媒
- 持続可能な素材
背景:
- 伝統的なポリカーボネート合成には,しばしば過渡金属が含まれており,色彩のある製品を生み出し,浄化が必要です.
- CO2でエポキシドを共聚する以前の方法は,通常,複雑な触媒システムを必要とします.
研究 の 目的:
- アニオンコポリメリゼーションによるポリカーボネート合成のための新しい,金属のない方法を開発する.
- プロピレン酸化物 (PO) やサイクロヘクセン酸化物 (CHO) といったエポキシドで二酸化炭素 (CO2) を効率的に共聚させる.
主な方法:
- エポキシドを活性化するためにルイス酸 (トリエチルボラン) を使用した金属のない条件下でアニオンコポリマー化.
- オニウム塩 (アンモニア,フォスフォニウム,フォスファゼニウム) を利用してCO2を活性化し,ポリメリゼーションを開始します.
- CO2のPOとCHOとの共ポリマー化について調べています.
主要な成果:
- CO2とPOとCHOを交互に合成した
- 高炭酸含量 (ポリプロピレン炭酸の92-99%) と高回転量 (POの約500トン,CHOの約4000トン) を達成した.
- 合成後の浄化なしで無色なポリマーを生成する金属のないプロセスが実証されました.
結論:
- この金属のないアプローチは,CO2とエポキシドからポリカーボネートへの簡素で効率的な経路を提供します.
- この方法は移行金属を避け,合成と精製を簡素化し,高品質の無色ポリマーを生成します.
- 高いTON値は,ポリマー合成におけるCO2利用のための無金属システムの触媒効率を示しています.
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