Patents by Inventor Christopher S. Liu

Christopher S. Liu 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).

  • Hydrocarbon compositions containing polyolefin graft polymers
    Patent number: 4764304
    Abstract: Dispersant viscosity index improvers for lubricating oils contain an EPR or EPT polymer onto which has been graft polymerized isocyanatoethyl methacrylate and thereafter reacted with N-methyl piperazine.
    Type: Grant
    Filed: September 25, 1986
    Date of Patent: August 16, 1988
    Assignee: Texaco Inc.
    Inventors: Maria M. Kapuscinski, Christopher S. Liu, William P. Hart
  • Hydrocarbon compositions containing polyolefin graft polymers
    Patent number: 4732942
    Abstract: Lubricating oil compositions of improved dispersancy contain an ethylene-propylene copolymer grafted onto which is acrylic acid dimer, the free carboxyl group of which has thereafter been amidized with diethylene triamine.
    Type: Grant
    Filed: September 2, 1986
    Date of Patent: March 22, 1988
    Assignee: Texaco Inc.
    Inventors: Christopher S. Liu, Benjamin J. Kaufman, Maria M. Kapucinski
  • Oil containing dispersant VII olefin copolymer
    Patent number: 4715975
    Abstract: A VII olefin copolymer, prepared by grafting allyl amine onto EPM or EPT, permits attainment of improved dispersancy and viscosity index in oils.
    Type: Grant
    Filed: August 20, 1984
    Date of Patent: December 29, 1987
    Assignee: Texaco Inc.
    Inventors: Maria M. Kapusciniski, Benjamin J. Kaufman, Christopher S. Liu
  • Lubricating oil containing dispersant VII and pour depressant
    Patent number: 4668412
    Abstract: Lubricating oils of improved properties contain a terpolymer of maleic acid anhydride and lauryl methacrylate and stearyl methacrylate which has been functionalized with dimethylaminopropylamine and a Mannich base of N-aminoethylpiperazine, paraformaldehyde, and 2,6-di-t-butyl phenol.
    Type: Grant
    Filed: June 27, 1985
    Date of Patent: May 26, 1987
    Assignee: Texaco Inc.
    Inventors: William P. Hart, Christopher S. Liu
  • Hydrocarbon compositions containing polyolefin graft polymers
    Patent number: 4640788
    Abstract: Lubricants of improved properties contain ethylene-propylene copolymers bearing graft units derived from, as a functional monomer, the reaction product of (i) an unsaturated aldehyde or ketone and (ii) a primary or secondary amine which contains at least one nitrogen atom in a heterocyclic ring.
    Type: Grant
    Filed: April 29, 1985
    Date of Patent: February 3, 1987
    Assignee: Texaco Inc.
    Inventors: Maria M. Kapuscinski, Christopher S. Liu, William P. Hart, Larry D. Grina
  • Reaction products of glycidyl derivatized polyolefins and 5-aminotetrazoles and lubricating oils containing same
    Patent number: 4500440
    Abstract: Improvements in dispersant viscosity index improvers having antioxidant properties and their use in lubricating oils are disclosed. An ethylene-propylene copolymer rubber has grafted thereon a vinyl monomer having an epoxy group to form a precursor which is condensed with a 5-aminotetrazole by ring opening of the pendent epoxide group.
    Type: Grant
    Filed: July 6, 1984
    Date of Patent: February 19, 1985
    Assignee: Texaco Inc.
    Inventors: Benjamin J. Kaufman, Christopher S. Liu, Rodney L. Sung