Slurry-phase ethylene polymerization using pentafluorophenyl- and pentafluorophenoxy-modified solid polymethylaluminoxanes

Journal article

Postsynthesis modification of solid polymethylaluminoxane (sMAO) with tris(pentafluorophenyl)borane or pentafluorophenol produces highly active metallocene supports "sMMAOs" for use in slurry-phase ethylene polymerization. Characterization of the sMMAOs using elemental analysis, BET isotherm, SEM-EDX, diffuse FT-IR, and solid-state NMR spectroscopy reveals that the surface methyl groups are exchanged for C 6 F 5 and C 6 F 5 O moieties respectively, giving a material with reduced aluminum content and a lower specific surface area than sMAO. rac-Ethylenebis(1-indenyl) zirconium dichloride, {(EBI)ZrCl 2 } immobilized on B(C 6 F 5 ) 3 - and C 6 F 5 OH-modified sMAO displayed activity increases of 66% and 71% respectively for ethylene polymerization compared to the same zirconocene catalyst precursor on unmodified sMAO. In the case of B(C 6 F 5 ) 3 -modified sMAO, this enhanced polymerization activity is accompanied by excellent control of polymer particle size and morphology, and a small decrease in polymer molecular weight and polydispersities.

Authors: Kilpatrick, A; Rees, N; Sripothongnak, S; Buffet, J; O'Hare, D

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: American Chemical Society
• Journal: Organometallics
• Volume: 37
• Issue: 1
• Pages: 156-164
• Publication date: 2017-12-27
• Acceptance date: 2017-12-14
• DOI: 10.1021/acs.organomet.7b00846
• EISSN: 1520-6041
• ISSN: 0276-7333