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Influence of internal and external electron-donors on the activity and stereospecificity of ziegler-natta catalysts

✍ Scribed by F.M.B. Coutinho; L.C. Santa Maria

Publisher: Elsevier Science
Year: 1991
Tongue: English
Weight: 213 KB
Volume: 27
Category: Article
ISSN: 0014-3057
DOI: 10.1016/0014-3057(91)90046-q

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✦ Synopsis

Studies have been made of the effects of tributyl phosphate, ethyl benzoate (EB) and diisobutyl phthalate (DIBP) as second internal bases on the Ziegler-Natta catalysts prepared by the reduction of TIC14 with AIC1Et2 in the presence of n-butyl ether (DBE) as a first internal base. These catalysts were evaluated in propylene polymerization in the presence or absence of external bases (EB, DIBP and DBE). The effects of internal and external bases on the catalyst activity and stereospeeificity are discussed.

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