Patents by Inventor Robert T. Li
Robert T. Li has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 11130828Abstract: Disclosed is a solution polymerization process, or, alternatively, a method of delivering powder catalysts to a solution polymerization reactor, comprising combining a homogeneous single-site catalyst precursor with ?-olefin monomers to form a polyolefin, wherein the homogeneous single-site catalyst precursor is in the form of (i) a dry powder, (ii) suspended in a aliphatic hydrocarbon solvent, or (iii) suspended in an oil or wax, wherein the homogeneous single-site catalyst precursor is at a concentration greater than 0.8 mmole/liter when suspended in the aliphatic hydrocarbon solvent prior to entering the solution polymerization reactor.Type: GrantFiled: September 11, 2019Date of Patent: September 28, 2021Assignee: ExxonMobil Chemical Patents Inc.Inventors: Peijun Jiang, Robert T. Li, Jay L. Reimers
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Patent number: 10544246Abstract: Disclosed is a solution polymerization process, or, alternatively, a method of delivering powder catalysts to a solution polymerization reactor, comprising combining a homogeneous single-site catalyst precursor with ?-olefin monomers to form a polyolefin, wherein the homogeneous single-site catalyst precursor is in the form of (i) a dry powder, (ii) suspended in a aliphatic hydrocarbon solvent, or (iii) suspended in an oil or wax, wherein the homogeneous single-site catalyst precursor is at a concentration greater than 0.8 mmole/liter when suspended in the aliphatic hydrocarbon solvent prior to entering the solution polymerization reactor.Type: GrantFiled: July 10, 2017Date of Patent: January 28, 2020Assignee: ExxonMobil Chemical Patents Inc.Inventors: Peijun Jiang, Robert T. Li, Jay L. Reimers
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Publication number: 20200002451Abstract: Disclosed is a solution polymerization process, or, alternatively, a method of delivering powder catalysts to a solution polymerization reactor, comprising combining a homogeneous single-site catalyst precursor with ?-olefin monomers to form a polyolefin, wherein the homogeneous single-site catalyst precursor is in the form of (i) a dry powder, (ii) suspended in a aliphatic hydrocarbon solvent, or (iii) suspended in an oil or wax, wherein the homogeneous single-site catalyst precursor is at a concentration greater than 0.8 mmole/liter when suspended in the aliphatic hydrocarbon solvent prior to entering the solution polymerization reactor.Type: ApplicationFiled: September 11, 2019Publication date: January 2, 2020Inventors: Peijun Jiang, Robert T. Li, Jay L. Reimers
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Publication number: 20180044453Abstract: Disclosed is a solution polymerization process, or, alternatively, a method of delivering powder catalysts to a solution polymerization reactor, comprising combining a homogeneous single-site catalyst precursor with ?-olefin monomers to form a polyolefin, wherein the homogeneous single-site catalyst precursor is in the form of (i) a dry powder, (ii) suspended in a aliphatic hydrocarbon solvent, or (iii) suspended in an oil or wax, wherein the homogeneous single-site catalyst precursor is at a concentration greater than 0.8 mmole/liter when suspended in the aliphatic hydrocarbon solvent prior to entering the solution polymerization reactor.Type: ApplicationFiled: July 10, 2017Publication date: February 15, 2018Inventors: Peijun Jiang, Robert T. Li, Jay L. Reimers
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Patent number: 7638671Abstract: The present invention provides a method of producing oligomers of olefins, comprising reacting olefins with a catalyst under oligomerization conditions. The catalyst can be the product of the combination of a chromium compound and a heteroaryl-amine compound. In particular embodiments, the catalyst compound can be used to trimerize or tetramerize ethylene to 1-hexene, 1-octene, or mixtures of 1-hexene and 1-octene.Type: GrantFiled: June 27, 2008Date of Patent: December 29, 2009Assignee: ExxonMobil Chemical Patents Inc.Inventors: David H. McConville, Lily Ackerman, Robert T. Li, Xiaohong Bei, Matthew C. Kuchta, Tom Boussie, John F. Walzer, Jr., Gary Diamond, Francis C. Rix, Keith A. Hall, Anne LaPointe, James Longmire, Vince Murphy, Pu Sun, Dawn Verdugo, Susan Schofer, Eric Dias
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Patent number: 7638670Abstract: The present invention provides a method of producing oligomers of olefins, comprising reacting olefins with a catalyst under oligomerization conditions. The catalyst can be the product of the combination of a chromium compound and a pyridyl amine or a heteroaryl-amine compound. In particular embodiments, the catalyst compound can be used to trimerize or tetramerize ethylene to 1-hexene, 1-octene, or mixtures of 1-hexene and 1-octene.Type: GrantFiled: August 8, 2008Date of Patent: December 29, 2009Assignee: ExxonMobil Chemical Patents Inc.Inventors: David H. McConville, Lily Ackerman, Robert T. Li, Xiaohong Bei, Matthew C. Kuchta, Tom Boussie, John F. Walzer, Jr., Gary Diamond, Francis C. Rix, Keith A. Hall, Anne LaPointe, James Longmire, Vince Murphy, Pu Sun, Dawn Verdugo, Susan Schofer, Eric Dias
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Publication number: 20080293899Abstract: The present invention provides a method of producing oligomers of olefins, comprising reacting olefins with a catalyst under oligomerization conditions. The catalyst can be the product of the combination of a chromium compound and a pyridyl amine or a heteroaryl-amine compound. In particular embodiments, the catalyst compound can be used to trimerize or tetramerize ethylene to 1-hexene, 1-octene, or mixtures of 1-hexene and 1-octene.Type: ApplicationFiled: August 8, 2008Publication date: November 27, 2008Inventors: David H. McConville, Lily Ackerman, Robert T. Li, Xiahong Bei, Matthew C. Kuchta, Tom Boussie, John F. Walzer, JR., Gary Diamond, Francis C. Rix, Keith A. Hall, Anne LaPointe, James Longmire, Vince Murphy, Pu Sun, Dawn Verdugo, Susan Schofer, Eric Dias
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Publication number: 20080269443Abstract: The present invention provides a method of producing oligomers of olefins, comprising reacting olefins with a catalyst under oligomerization conditions. The catalyst can be the product of the combination of a chromium compound and a heteroaryl-amine compound. In particular embodiments, the catalyst compound can be used to trimerize or tetramerize ethylene to 1-hexene, 1-octene, or mixtures of 1-hexene and 1-octene.Type: ApplicationFiled: June 27, 2008Publication date: October 30, 2008Inventors: David H. McConville, Lily Ackerman, Robert T. Li, Xiaohong Bei, Mathew C. Kuchta, Tom Boussie, John F. Walzer, Gary Diamond, Francis C. Rix, Keith A. Hall, Anne LaPointe, James Longmire, Vince Murphy, Pu Sun, Dawn Verdugo, Susan Schofer, Eric Dias
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Patent number: 7425661Abstract: The present invention provides a method of producing oligomers of olefins, comprising reacting olefins with a catalyst under oligomerization conditions. The catalyst can be the product of the combination of a chromium compound and a pyridyl amine or a heteroaryl-amine compound. In particular embodiments, the catalyst compound can be used to trimerize or tetramerize ethylene to 1-hexene, 1-octene, or mixtures of 1-hexene and 1-octene.Type: GrantFiled: March 9, 2006Date of Patent: September 16, 2008Assignee: ExxonMobil Chemicals Patents Inc.Inventors: David H. McConville, Lily Ackerman, Robert T. Li, Xiaohong Bei, Matthew C. Kuchta, Tom Boussie, John F. Walzer, Jr., Gary Diamond, Francis C. Rix, Keith A. Hall, Anne LaPointe, James Longmire, Vince Murphy, Pu Sun, Dawn Verdugo, Susan Schofer, Eric Dias
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Patent number: 7414006Abstract: The present invention provides a method of producing oligomers of olefins, comprising reacting olefins with a catalyst under oligomerization conditions. The catalyst can be the product of the combination of a chromium compound and a heteroaryl-amine compound. In particular embodiments, the catalyst compound can be used to trimerize or tetramerize ethylene to 1-hexene, 1-octene, or mixtures of 1-hexene and 1-octene.Type: GrantFiled: March 9, 2006Date of Patent: August 19, 2008Assignee: ExxonMobil Chemical Patents Inc.Inventors: David H. McConville, Lily Ackerman, Robert T. Li, Xiaohong Bei, Matthew C. Kuchta, Tom Boussie, John F. Walzer, Jr., Gary Diamond, Francis C. Rix, Keith A. Hall, Anne LaPointe, James Longmire, Vince Murphy, Pu Sun, Dawn Verdugo, Susan Schofer, Eric Dias
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Patent number: 7297747Abstract: Olefin polymerization processes using catalyst systems based on metallocenes and olefin, in particular, propylene polymers obtainable thereby. The metallocenes may be represented by the formula: wherein M1 preferably is zirconium or hafnium; and R12 is different from hydrogen.Type: GrantFiled: October 27, 2004Date of Patent: November 20, 2007Assignee: ExxonMobil Chemical Patents Inc.Inventors: James R. Hart, William T. Haygood, Terry J. Burkhardt, Robert T. Li
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Patent number: 7122498Abstract: Metallocenes and catalyst systems for olefin polymerization derived therefrom. The metallocenes may be represented by the formula: wherein M1 preferably is zirconium or hafnium; and R12 is different from hydrogen.Type: GrantFiled: June 29, 2001Date of Patent: October 17, 2006Assignee: ExxonMobil Chemical Patents Inc.Inventors: James R. Hart, William T. Haygood, Terry J. Burkhardt, Robert T. Li
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Patent number: 7081543Abstract: The present invention relates to ligands and the synthesis of those ligands for use in metallocene complexes. More particularly, the present invention relates to the synthesis of diarylsilyl bridged biscyclopentadienes using diarylsilyldisulfonates. Even more particularly, the present invention describes Group IV metallocenes containing diarylsilyl bridged bis-cyclopentadienyl ligands prepared from contacting a diarylsilyldisulfonate with an organometallic indenyl reagent.Type: GrantFiled: July 13, 2005Date of Patent: July 25, 2006Assignee: ExxonMobil Chemical Patents Inc.Inventors: Francis C. Rix, Terry J. Burkhardt, Robert T. Li, William T. Haygood, Jr.
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Patent number: 6960676Abstract: The present invention relates to ligands and the synthesis of those ligands for use in metallocene complexes. More particularly, the present invention relates to the synthesis of diarylsilyl bridged biscyclopentadienes using diarylsilyldisulfonates. Even more particularly, the present invention describes Group IV metallocenes containing diarylsilyl bridged bis-cyclopentadienyl ligands prepared from contacting a diarylsilyldisulfonate with an organometallic indenyl reagent.Type: GrantFiled: February 8, 2001Date of Patent: November 1, 2005Assignee: ExxonMobil Chemical Patents Inc.Inventors: Francis C. Rix, Terry J. Burkhardt, Robert T. Li, William T. Haygood, Jr.
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Patent number: 6903229Abstract: This invention relates to metallocene compositions and their use in the preparation of catalyst systems for olefin polymerization, particularly propylene polymerization. The metallocene compositions may be represented by the formula: wherein R3 are identical or different and are each a halogen atom, a C1-C10 alkyl group which may be halogenated, a C6-C10 aryl group which may be halogenated, a C2-C10 alkenyl group, a C7-C40-arylalkyl group, a C7-C40 alkylaryl group, a C8-C40 arylalkenyl group, a —NR?2, —SR?, —OR?, —OSiR?3 or —PR?2 radical, wherein R? is one of a halogen atom, a C1-C10 alkyl group, or a C6-C10 aryl group, and R9 and R11 are identical or different and are a Group 14 radical having from 1 to 20 carbon atoms or are each primary, secondary or tertiary butyl groups, aryl groups, isopropyl groups, fluoroalkyl groups, trialkyl silyl groups, or other groups of similar size.Type: GrantFiled: January 31, 2002Date of Patent: June 7, 2005Assignee: ExxonMobil Chemical Patents Inc.Inventors: Terry J. Burkhardt, Udo M. Stehling, James R. Hart, William T. Haygood, Jr., Robert T. Li, James C. Vizzini, Matthew C. Kuchta
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Patent number: 6894179Abstract: This invention relates to metallocene compositions and their use in the preparation of catalyst systems for olefin polymerization, particularly propylene polymerization.Type: GrantFiled: January 31, 2002Date of Patent: May 17, 2005Assignee: Exxon Mobil Chemical Patents Inc.Inventors: Matthew C. Kuchta, Udo M. Stehling, Robert T. Li, William T. Haygood, Jr., Terry J. Burkhardt
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Patent number: 6888017Abstract: This invention relates to bridged indenyl metallocene compositions and their use in the preparation of catalyst systems for olefin polymerization, particularly propylene polymerization. The bridge may be represented by the formula: wherein: R17 to R24 are identical or different, and are one of a hydrogen atom, a C1-C10 alkyl group, a C1-C10 alkoxy group, a C6-C10 aryl group, a C6-C10 aryloxy group, a C2-C10 alkenyl group, a C7-C40 arylalkyl group, a C7-C40 alkylaryl group, a C8-C40 arylalkenyl group, or a halogen atom, or together are a conjugated diene which is optionally substituted with one or more hydrocarbyl, tri(hydrocarbyl)silyl groups or hydrocarbyl, tri(hydrocarbyl)silylhydrocarbyl groups, said diene having up to 30 atoms not counting hydrogen; or two or more adjacent radicals R17 to R24, including R20 and R21, together with the atoms connecting them form one or more rings; and M2 is carbon, silicon, germanium or tin.Type: GrantFiled: January 31, 2002Date of Patent: May 3, 2005Assignee: ExxonMobil Chemical Patents Inc.Inventors: Matthew C. Kuchta, Udo M. Stehling, Robert T. Li, William T. Haygood, Jr., Terry J. Burkhardt
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Patent number: 6870016Abstract: Olefin polymerization processes using catalyst systems based on metallocenes and olefin, in particular, propylene polymers obtainable thereby. The metallocenes may be represented by the formula: ? wherein M1 preferably is zirconium or hafnium; and R12 is different from hydrogen.Type: GrantFiled: June 29, 2001Date of Patent: March 22, 2005Assignee: ExxonMobil Chemical Patents Inc.Inventors: Terry J. Burkhardt, James R. Hart, William T. Haygood, Robert T. Li
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Patent number: 6809057Abstract: An olefin polymerization catalyst system, comprising a catalyst represented by the general formula CrR4, wherein each R is independently a hydrocarbyl or substituted hydrocarbyl, with the proviso that R may not be a cyclopentadienyl group, an activator represented by the general formula, MQ2, where M is a Group II metal, where each Q is independently an alkyl, or substituted alkyl; and a support. The support may be organic or inorganic. Ethylene and one or more olefins may be polymerized by the catalyst system.Type: GrantFiled: February 10, 2003Date of Patent: October 26, 2004Assignee: ExxonMobil Chemical Patents Inc.Inventors: Zerong Lin, Robert T. Li, Anthony N. Speca, Stanley J. Katzen, David H. McConville
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Publication number: 20040157729Abstract: An olefin polymerization catalyst system, comprising a catalyst represented by the general formula CrR4, wherein each R is independently a hydrocarbyl or substituted hydrocarbyl, with the proviso that R may not be a cyclopentadienyl group, an activator represented by the general formula, MQ2, where M is a Group II metal, where each Q is independently an alkyl, or substituted alkyl; and a support. The support may be organic or inorganic. Ethylene and one or more olefins may be polymerized by the catalyst system.Type: ApplicationFiled: February 10, 2003Publication date: August 12, 2004Inventors: Zerong Lin, Robert T. Li, Anthony N. Speca, Stanley J. Katzen, David H. McConville