プロピレン酸化物と二酸化炭素の交替共聚化のためのコバルト触媒:高い活性と選択性を組み合わせる
Claire T Cohen1, Tony Chu, Geoffrey W Coates
1Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, NY 14853-1301, USA.
Journal of the American Chemical Society
|August 4, 2005
まとめ
高活性コバルト触媒は,プロピレン酸化物とCO2の効率的で生きた共ポリメリゼーションを可能にし,制御された微細構造を持つポリプロピレン炭酸塩 (PPC) を生成します. これらの触媒は,低CO2圧力下でも,活性と選択性を高めます.
科学分野:
- 有機金属化学 有機金属化学
- ポリマーサイエンスの科学
- カタリシス カタリシス カタリシス
背景:
- CO2利用のための効率的な触媒の開発は,持続可能な化学にとって極めて重要です.
- ポリプロピレン炭酸 (PPC) は,潜在的な応用がある生物分解性ポリマーです.
- リビングコポリメリゼーションは,ポリマーの特性に対する正確な制御を提供します.
研究 の 目的:
- 新しいコバルト-塩素複合体を触媒として合成し,特徴づけること.
- プロピレン酸化物 (PO) とCO2の生きた交互の共ポリメリゼーションを調査する.
- PPC特性に対する触媒構造と共触媒の影響を調査する.
主な方法:
- (塩酸) CoX複合体の合成 (X = ハリドまたはカルボキシラート).
- 様々なコバルト触媒とコカタライスト ([PPN]Cl,[PPN][OBzF(5)) を使った共聚化反応.
- ポリマーの微細構造,分子量分布 (MWD),および触媒活性の分析.
主要な成果:
- コバルト-塩素複合体は,POとCO2の交互の共ポリメリゼーションを交代して,生きているために非常に活発な触媒です.
- PPCが生産した産物は,高い地域規則性 (最大99%の炭酸結合) と狭いMWDを示しています.
- コカタライストは,触媒活性,ステレオ選択性,および地域選択性を著しく高め,高回転周波数 (最大1100h−1) を達成します.
- モノマーと触媒の立体化学は,PPCの微細構造に劇的な影響を及ぼし,地域規則性とシンディオ濃縮の制御を可能にします.
結論:
- 新しいコバルト塩溶液触媒とコカタリストシステムは,PO/CO2共ポリメリゼーションにおいて前例のない効率と制御を提供します.
- この研究は,機能的なポリプロピレン炭酸の合成を,それに合わせた微小構造で進めています.
- この発見は,CO2を価値あるポリマーに変換する有望な経路を提供している.
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