Zirconium-chelate and mono-η- cyclopentadienyl zirconium-chelate/ methylalumoxane systems as soluble Ziegler–Natta olefin polymerization catalysts

✍ Scribed by Christoph Janiak; Katharina C. H. Lange; Tobias G. Scharmann

• Publisher: John Wiley and Sons
• Year: 2000
• Tongue: English
• Weight: 90 KB
• Volume: 14
• Category: Article
• ISSN: 0268-2605
• DOI: 10.1002/(sici)1099-0739(200006)14:6<316::aid-aoc990>3.0.co;2-u

✦ Synopsis

Zirconium-chelate and mono-h-cyclopentadienyl zirconium-chelate complexes were tested as ethene and propene polymerization catalysts in combination with methylalumoxane (MAO) as a co-catalyst: in particular (acac) n ZrCl 4Àn (1a-c) (acac = acetylacetonato), (dbm 5) and (h-C 5 H 5 )[(Me 3 SiN) 2 CPh]ZrCl 2 (6). Polymerization productivities comparable with the (h-C 5 H 5 ) 2 ZrCl 2 reference system were observed towards ethene for all of the above complexes. In addition, compound 6 showed some minor polymerization activity towards propene. Ethylalumoxane or isobutylalumoxane did not exhibit a co-catalytic activity for these chelate complexes; in combination with MAO these higher alumoxanes were even found to be deactivating 91 Zr NMR data are reported for 1b, 1c, 4 and 5.