ハフニウム・ピリジル・アミド触媒による1オクテンのポリメリゼーションとクエンチ・ラベリング法による連鎖移転のメカニズム研究
Eric S Cueny1, Heather C Johnson1, Bernie J Anding1
1Department of Chemistry, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 53706, United States.
Journal of the American Chemical Society
|August 2, 2017
まとめ
染色体消火標識は,1オクテンのポリメリゼーションにおける活性ハフニウム触媒を定量化する. この方法は,ポリマーの分子量分布を明らかにし,触媒の最適化とメカニズムの研究に役立ちます.
科学分野:
- ポリマー化学
- 有機金属化学
背景:
- 活性触媒の定量化は,ポリメリゼーション運動を理解するために不可欠です.
- 低濃度で高効率の 商用催化剤に 苦戦しています
研究 の 目的:
- 活性ハフニウム触媒の定量化のための染色体消火ラベルを開発し,適用する.
- ハフニウム触媒を用いて1オクテンのポリマー化機構を調査する.
- ハフニウム結合ポリマーの分子量分布と散発ポリマーを比較する.
主な方法:
- ハフニウム結合ポリマーの染色体消火ラベル
- UVと屈折指数 (RI) の検出器による二重検出ゲル浸透染色学 (GPC)
- モノメア消費と活性触媒濃度の時間経過に関する運動分析
主要な成果:
- 活性ハフニウム触媒の濃度が測定されました
- Hf結合型および散発型ポリマーの分別分布が観察された.
- ハフニウム前触媒の最適活性化条件を決定した.
- 亜鉛ポリマーの存在でハフニウム結合ポリマーの選択的なラベル付けが実証されています.
- 亜鉛ダイエチル (ZnEt2) はHfの伝播速度に影響を及ぼさないが,迅速で不可逆的な連鎖移転を経験していることが確認された.
結論:
- 染色体消火ラベルは,1オクテンのポリメリゼーションにおける活性ハフニウム触媒の研究に有効である.
- このテクニックは,触媒の行動とチェーン転送プロセスに関する貴重な機械的洞察を提供します.
- この方法は,専門機器を必要としない商用ポリメリゼーション触媒に適用できます.
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