Ethylene polymerization initiated by anchored CpIndZrCl2 on silica with hexamethyltrisiloxane and pentamethylene spacers

✍ Scribed by Dong-Ho Lee; Hun-Bong Lee; Seok Kyun Noh; Byung Kyu Song; Sah Mun Hong

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 247 KB
• Volume: 71
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/(sici)1097-4628(19990214)71:7<1071::aid-app5>3.0.co;2-c

✦ Synopsis

For ethylene polymerization, the supported metallocene catalyst was prepared by anchoring CpIndZrCl 2 on silica with an appropriate spacer. The three procedures were applied for CpIndZrCl 2 anchoring on silica with a hexamethyltrisiloxane or pentamethylene spacer. The anchoring procedures exerted a strong influence on the catalyst activity since the different anchoring methods gave the formation of different structures of active sites. With the new anchoring route, it was possible to prepare the "heterogeneous single-site" catalyst which was found to have only one catalyst structure on silica and exhibited a higher catalyst activity than that of the other supported catalysts. At a polymerization temperature of 70°C, the activity of the heterogeneous single-site catalyst was comparable to that of the unsupported homogeneous zirconocene.