Details

Autor(en) / Beteiligte

• dos Santos, João Henrique Zimnoch
• Greco, Paula Palmeira
• Stedile, Fernanda Chiarello
• Dupont, Jairton

Titel

Organosilicon-modified silicas as support for zirconocene catalyst

Ist Teil von

• Journal of molecular catalysis. A, Chemical, 2000-03, Vol.154 (1), p.103-113

Ort / Verlag

Amsterdam: Elsevier B.V

Erscheinungsjahr

2000

Quelle

Elsevier Journal Backfiles on ScienceDirect (DFG Nationallizenzen)

Beschreibungen/Notizen

• The metallocene ( nBuCp) 2ZrCl 2 was grafted on partially dehydroxilated commercial silica (Grace 948) whose surface had been chemically modified by wet impregnation of an organosilane (Ph 3SiCl, Me 3SiCl, or Me 2SiHCl) aiming at supported catalyst systems with well spaced α-olefin polymerization active centers. Final Zr loadings were determined by Rutherford Backscattering Spectrometry (RBS), and modifications at the silica surface after each preparation step were monitored by in situ FT-IR spectroscopy. These catalyst systems produced polyethylenes with narrow molecular weight distribution when methylaluminoxane was used as cocatalyst, with twice the activity of ( nBuCp) 2ZrCl 2 supported on bare SiO 2. Effects of support structure and chemical modification on catalyst performance are presented and discussed.