Polymer-supported zirconocene catalyst for ethylene polymerization

✍ Scribed by Fenghua Meng; Guangqian Yu; Baotong Huang

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 184 KB
• Volume: 37
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(19990101)37:1<37::aid-pola5>3.0.co;2-o

✦ Synopsis

The use of crosslinked poly(styrene-co-4-vinylpyridine) having functional groups as the support for zirconocene catalysts in ethylene polymerization was studied. Several factors affecting the activity of the catalysts were examined. Conditions like time, temperature, Al/N (molar ratio), Al/Zr (molar ratio), and the mode of feeding were found having no significant influence on the activity of the catalysts, while the state of the supports had a great effect on the catalytic behavior. The activity of the catalysts sharply increased with either the degree of crosslinking or the content of 4-vinylpyridine in the support. Via aluminum compounds, AlR 3 or methylaluminoxane (MAO), zirconocene was attached on the surface of the support. IR spectra showed an intensified and shifted absorption bands of CON in the pyridine ring, and a new absorption band appeared at about 730 cm Ϫ1 indicating a stable bond AlON formed in the polymer-supported catalysts. The formation of cationic active centers was hypothesized and the performance of the polymer-supported zirconocene was discussed as well.