Isospecific Pseudo-Helical Zirconocenium Catalysts
作者： John A. Ewen , Michael J. Elder
DOI: 10.1007/978-3-642-79136-9_6
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摘要: High molecular weight, isotactic polypropylene is obtained with MAO and Me2Si[l-Cp-3-t-Bu-l’-Flu]ZrCl2 (1-MAO) Me2C[1-Cp-3-t-Bu-1 ‘-Flu]ZrCl2 (2-MAO) catalysts (MAO = methylaluminoxane; Flu fluorenyl; Cp cyclopentadienyl.) Atactic polymers are not produced since meso isomers of the pseudo-helicenes impossible. The… mmmrrmmm… polymer microstructure that for enantiomorphic site-control stereoregulation model. 1 more stereospecific than 2. The relative stereospecificities 2 conform to trend other pairs specific analogs Me2C Me2Si bridged.
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