Polymerization of styrene with supported half-sandwich complexes

✍ Scribed by W. Kaminsky; D. Arrowsmith; C. Strübel

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 163 KB
• Volume: 37
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(19990801)37:15<2959::aid-pola29>3.0.co;2-s

✦ Synopsis

Polymerizations of styrene were carried out with half-sandwich complexes supported on silica, CpTiX 3 /MAO/SiO 2 (X ϭ Cl, F). The optimum values for the polymerization time, the amount of cocatalyst and the Al support /Ti ratio were found for the trichlorinated system. The highest activity obtained was 3,100 g sPS/(mol Ti ϫ h ϫ mol/L styrene). The trihalogenated complexes were compared to one another with respect to their polymerization rate. CpTiCl 3 /MAO/SiO 2 and CpTiF 3 /MAO/SiO 2 behave in a similar manner, suggesting that the active species of both half-sandwich complexes on the support are the same. Furthermore, aging experiments were carried out with CpTiCl 3 /MAO/SiO 2 and, surprisingly, deactivation was observed, as opposed to supported zirconocenes which gain stability against deactivation reactions when anchored to a carrier.