High activity carbenium-activated polymerization catalysts
AssigneeExxonMobil Chemical Patents Inc.
InventorsDonna Jean Crowther, Bernard Jean Folie
Life of this patent
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Abstract
This application discloses triphenyl carbenium NCA's as catalyst activators for a class of asymmetrically bridged hafnocene catalyst precursors. These catalyst precursors are activated into olefin polymerization catalysts and are suitable for gas, solution, and slurry-phase polymerization reactions. The disclosed bridge is methylenyl- or silanylenyl-based and is optionally, alkyl or aryl substituted. The catalytic activity of the disclosed hafnocene catalyst precursors is substantially enhanced over identical catalysts that are activated with other activators.
Claims20
A metallocene catalyst system comprising an ion pair formed by contacting a metallocene and an activator wherein:
- (a) the metallocene is described by the formula
- T(CpRn)(Cp′R′m)HfQ2
- wherein:
- (i) Cp and Cp′ are cyclopentadienyl ligands;
- (ii) Each R and R′ are the same or different bydrocarbyl radicals having 1-20 carbon atoms;
- (iii) T is a bridge between Cp and Cp′, and comprises a subtituted or unsubstituted methylene or silylene radical;
- (iv) each Q is a hydrocarbyl radical having 1-20 carbon atoms or is a halogen;
- (v) n is the number of hydrocarbyl substituents on Cp and n=0-4;
- (vi) in is the number of hydrocarbyl substituents on Cp′ and m=0-4;
- and
- (vii) wherein Cp, Cp′, R, R′, m and n are selected such that CpRn is not equal to Cp′R′m, and wherein Cp′R′m forms a substituted or unsubstituted indenyl or fluorenyl ligand;
- and
- (b) the activator is described by the formula:
- [Ar3C][NCA]
- wherein:
- (i) Ar is an aryl ligand;
- (ii) Ar3C is a triarylcarbenium;
- and
- (iii) NCA is a non-coordinating anion.
A metallocene catalyst system comprising an ion pair formed by contacting a metallocene and an activator wherein:
- (a) the metallocene is described by the formula
- T(CpRn)(CP′R′m)HfQ2
- wherein:
- (i) Cp and Cp′ are cyclopentadienyl ligands;
- (ii) each R and R′ are the same or different hydrocarbyl radicals having 1-20 carbon atoms;
- (iii) T is a bridge between Cp and Cp′, and comprises an aryl substituted methylene or silylene radical;
- (iv) each Q is a hydrocarbyl radical having 1-20 carbon atoms;
- (v) n is the number of hydrocarbyl substituents on Cp and n=0-4;
- (vi) m is the number of hydrocarbyl substituents on Cp′ and m=0-4;
- and
- (vii) wherein Cp, Cp′, R, R′, m and n are selected such that CpRn is not equal to Cp′R′m, and
- (b) the activator is described by the formula:
- [Ar3C][NCA]
- wherein:
- (i) Ar is an aryl ligand;
- (ii) Ar3C is a triarylcarbenium;
- and
- (iii) NCA is a non-coordinating anion.
A metallocene catalyst system comprising an ion pair formed by contacting:
- (1) a metallocene selected from the group consisting of:
- (para-n-butylphenyl)(para-t-butylphenyl)methylene(fluorenyl)(indenyl) hafnium dimethyl,
- (para-n-propylphenyl)(para-methylphenyl)methylene(fluorenyl)(indenyl) hafnium dimethyl,
- di(para-n-butylphenyl)methylene(2,7-di-tertbutyl-fluorenyl) (indenyl) hafnium dimethyl,(para-n-butylphenyl)(para-t-butylphenyl)methylene (2,7-di tertbutyl fluorenyl)(indenyl) hafnium dimethyl,
- (para-n-butylphenyl)(para-t-butylphenyl)methylene (2,7-dimethyl fluorenyl)(indenyl) hafnium dibenzyl
- di(para-n-butylphenyl)methylene(fluorenyl)(indenyl)hafnium dimethyl,
- (para-n-propylphenyl)(para-i-propylphenyl)silyl(fluorenyl)(fluorenyl) hafnium di-t-butyl,
- di(para-n-propylphenyl)methylene(2,7-di-tert-butyl-5-methylfluorenyl) (fluorenyl)hafnium dimethyl.
- (para-n-propylphenyl)(para-i-propylphenyl)methylene(fluorenyl) (cyclopentadienyl)hafnium dimethyl,
- (para-n-butylphenyl)(para-t-butylphenyl)methylene(fluorenyl) (cyclopentadienyl)hafnium dimethyl,
- di(para-n-butylphenyl)methylene(2,7-di tertbutyl fluorenyl) (cyclopentadienyl)hafnium dimethyl,
- (para-n-butylphenyl)(para-t-butylphenyl)methylene(2.7-di tertbutyl fluorenyl) (cyclopentadienyl) hafnium dimethyl,
- di(para-n-butylphenyl)methylene (2,7-dimethyl fluorenyl)(cyclopentadienyl) hafnium dimethyl, and
- di(para-n-butylphenyl)methylene (2,7-dimethyl fluorenyl)(cyclopentadienyl) hafnium dibenzyl;
- and
- (2) an activator selected from the group consisting of:
- tropillium tetrakis(pefluoronapthyl)borate, tetrakis(perfluoro-4-biphenyl) borate, triphenylmethylium tetrakis(perfluoronapthyl) borate,
- tetrakis(perfluoro-4-biphenyl)borate, benzene (diazonium) tetrakis(perfluoronapthyl) borate, tetrakis(perfluoro-4-biphenyl) borate,
- tropillium tetrakis(perfluoronapthyl)borate, tetrakis(perfluoro-4-biphenyl)borate, triphenylmethylium tetrakis(perfluoronapthyl) borate,
- tetrakis(perfluoro-4-biphenyl)borate, benzene (diazonium) tetrakis(perfluoronapthyl) borate, tetrakis(perfluoro-4-biphenyl) borate,
- tropillium tetrakis(perfluoronapthyl) borate, tetrakis(perfluoro-4-biphenyl)borate, triphenylmethylium tetrakis(perfluoronapthyl) borate,
- tetrakis(perfluoro-4-biphenyl)borate, benzene (diazonium) tetrakis(perfluoronapthyl) borate, and tetrakis(perfluoro-4-biphenyl)borate.
Dependencies are inferred from the claim text.