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RESEARCH PRODUCT

Tritylpyridinium tetrakis(pentafluorophenyl)borate as an efficient activator for “constrained-geometry” catalysts in ethylene polymerization

Kittichote MusikabhummaThomas P. SpaniolJun Okuda

subject

EthyleneChemistryProcess Chemistry and TechnologyInorganic chemistryCationic polymerizationchemistry.chemical_elementHomogeneous catalysisPolyethyleneMedicinal chemistryCatalysisCatalysisHexanechemistry.chemical_compoundProton NMRPhysical and Theoretical ChemistryBoron

description

Abstract Ethylene polymerization with linked amido-cyclopentadienyl or “constrained-geometry” titanium catalysts, Ti(η 5 :η 1 -C 5 Me 4 SiMe 2 N t Bu)X 2 (X=Me, Bz, Cl), activated by tritylpyridinium tetrakis(entafluorophenyl)borate, [Ph 3 C(NC 5 H 5 )] [B(C 6 F 5 ) 4 ], and silica-supported tritylpyridinium tetrakis(entafluorophenyl)borate (PySTB) was found to proceed with high activity. 1 H NMR spectra in CD 2 Cl 2 suggest that ([Ti(η 5 :η 1 -C 5 Me 4 ,SiMe 2 N t Bu)Me (NC 5 H 5 )] + is formed as the main cationic species. Using the heterogeneous cocatalyst PySTB in hexane, unexpectedly high ethylene polymerization activity was achieved, giving high molecular weight polyethylenes with excellent morphology and high bulk density (up to 0.46 g/cm 3 ).

yearjournalcountryeditionlanguage
2004-02-01Journal of Molecular Catalysis A: Chemical
https://doi.org/10.1016/j.molcata.2003.07.007