Patents by Inventor Frederick Y. Lo

Frederick Y. Lo 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).

  • Patent number: 5420220
    Abstract: A film of a linear low density copolymer of ethylene (LLDPE) having excellent processability, optical properties and impact strength, which exhibits a density of at least 0.900.
    Type: Grant
    Filed: March 25, 1993
    Date of Patent: May 30, 1995
    Assignee: Mobil Oil Corporation
    Inventors: Subrahmanyam Cheruvu, Frederick Y. Lo, S. Christine Ong
  • Patent number: 5332706
    Abstract: A support containing methylalumoxane and derivatives thereof is described which is formed by an incipient impregnation technique. The most preferred support is silica. Incipient impregnation in accordance with the invention provides a supported alumoxane, methylalumoxane, which substantially eliminates the problem of fluid bed reactor fouling when methylalumoxane is introduced into the reactor during its operation.In accordance with the invention, the process comprises providing methylalumoxane activated metallocene compound in particulate form as catalysts in fluid bed gas phase.
    Type: Grant
    Filed: December 28, 1992
    Date of Patent: July 26, 1994
    Assignee: Mobil Oil Corporation
    Inventors: Thomas E. Nowlin, Frederick Y. Lo, Ronald S. Shinomoto, Pradeep P. Shirodkar
  • Patent number: 5032562
    Abstract: There is disclosed a supported olefin polymerization catalyst composition comprising a precursor and a catalyst activator. The precursor comprises a magnesium compound, e.g., dibutylmagnesium, a cyclopentadienyl group-containing zirconium compound, and a titanium and/or a vanadium compound, e.g., TiCl.sub.4, and an organic compound, e.g., an alcohol. The catalyst activator is a mixture of a conventional Ziegler/Natta co-catalyst and a zirconium sites activator, e.g., methylaluminumoxane. The catalyst is used in the presence of small amounts of hydrogen to produce polymers having multimodal molecular weight distribution in a single reactor.
    Type: Grant
    Filed: December 27, 1989
    Date of Patent: July 16, 1991
    Assignee: Mobil Oil Corporation
    Inventors: Frederick Y. Lo, Thomas E. Nowlin, Pradeep P. Shirodkar
  • Patent number: 4876321
    Abstract: A catalyst composition for polymerizing alpha-olefins is prepared by treating a carrier containing OH groups with a liquid solution containing an excess of an organomagnesium composition with respect to the OH groups and contacting the thus-formed magnesium-containing carrier with a hydrocarbyl alcohol and at least one transition metal compound. Prior to contacting the magnesium-containing carrier with the alcohol, most of the liquid must be removed therefrom, so that it comprises not more than about 6% of the liquid. The amount of the transition metal compound is such that the molar ratio thereof to magnesium in the reaction mixture is about 0.3 to about 0.9. Also disclosed is a process for polymerizing alpha-olefins in the presence of the catalyst of the invention.
    Type: Grant
    Filed: February 20, 1987
    Date of Patent: October 24, 1989
    Assignee: Mobil Oil Corporation
    Inventors: Frederick Y. Lo, Thomas E. Nowlin, Margaret M. Wu
  • Patent number: 4760121
    Abstract: A catalyst composition for polymerizing alpha-olefins is prepared by treating a carrier containing OH groups with a liquid solution containing an excess of an organomagnesium composition with respect to the OH groups and contacting the thus-formed magnesium-containing carrier with a solution of at least one transition metal compound. Prior to contacting the magnesium-containing carrier with the transition metal compound, most of the liquid must be removed therefrom, so that it comprises not more than about 6% of the liquid. The amount of the transition metal compound is such that the molar ratio of the transition metal to magnesium in the reaction mixture is about 0.3 to about 0.9. Also disclosed is a process for polymerizing alpha-olefins in the presence of the catalyst of the invention.
    Type: Grant
    Filed: February 20, 1987
    Date of Patent: July 26, 1988
    Assignee: Mobil Oil Corporation
    Inventors: Frederick Y. Lo, Thomas E. Nowlin, Margaret M. Wu
  • Patent number: 4677087
    Abstract: A catalyst composition for polymerizing alpha-olefins is prepared by treating a carrier containing OH groups with a liquid solution containing an excess of an organomagnesium composition with respect to the OH groups and contacting the thus-formed magnesium-containing carrier with a solution of at least one transition metal compound. Prior to contacting the magnesium-containing carrier with the transition metal compound, most of the liquid must be removed therefrom, so that it comprises not more than about 6% of the liquid. The amount of the transition metal compound is such that the molar ratio of the transition metal to magnesium in the reaction mixture is about 0.3 to about 0.9. Also disclosed is a process for polymerizing alpha-olefins in the presence of the catalyst of the invention.
    Type: Grant
    Filed: January 3, 1986
    Date of Patent: June 30, 1987
    Assignee: Mobil Oil Corporation
    Inventors: Frederick Y. Lo, Thomas E. Nowlin, Margaret M. Wu
  • Patent number: 4668650
    Abstract: A catalyst composition for polymerizing alpha-olefins is prepared by treating a carrier containing OH groups with a liquid solution containing an excess of an organomagnesium composition with respect to the OH groups and contacting the thus-formed magnesium-containing carrier with a hydrocarbyl alcohol and at least one transition metal compound. Prior to contacting the magnesium-containing carrier with the alcohol, most of the liquid must be removed therefrom, so that it comprises not more than about 6% of the liquid. The amount of the transition metal compound is such that the molar ratio thereof to magnesium in the reaction mixture is about 0.3 to about 0.9. Also disclosed is a process for polymerizing alpha-olefins in the presence of the catalyst of the invention.
    Type: Grant
    Filed: January 3, 1986
    Date of Patent: May 26, 1987
    Assignee: Mobil Oil Corporation
    Inventors: Frederick Y. Lo, Thomas E. Nowlin, Margaret M. Wu