Synthesis of Novel Tetrahydrofluorenyl-Containing Group IV Metallocenes for the Ziegler-Natta Type Polymerization of -Olefins

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• 作者：Emma J. Thomas ; Marvin D. Rausch ; and James C. W. Chien
• 刊名：Organometallics
• 出版年：2000
• 出版时间：December 25, 2000
• 年：2000
• 卷：19
• 期：26
• 页码：5744 - 5749
• 全文大小：73K
• 年卷期：v.19,no.26(December 25, 2000)
• ISSN：1520-6041

文摘

Several new, novel bridged and unbridged bis-tetrahydrofluorenyl zirconocenes weresynthesized and evaluated as Ziegler-Natta type catalysts for ethylene and propylenepolymerization. The complexes were found to be highly stable compared to some bis-fluorenylzirconocenes. Polypropylene and polyethylene were produced in good yield usingthe new catalyst precursors with MAO or Trityl/TIBA as cocatalysts. Both the unsubstitutedand substituted bridged bis-tetrahydrofluorenyl zirconocenes were isolated as 50:50 mixturesof rac and meso isomers, which produced mostly atactic polypropylene. Partially crystallinepolypropylene was obtained at low temperatures with bis(3-methyltetrahydrofluorenyl)zirconium dichloride.