Patents by Inventor Dorothy C. Prem

Dorothy C. Prem 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: 4504605
    Abstract: A stable aqueous latex of a copolymer containing at least about 40 percent by weight of a polymerized olefinic unsaturated nitrile is described. The copolymer comprises a main polymer core of from about 40 to 100 percent by weight of the polymerized nitrile and from about 0 to about 60 percent by weight of at least one other polymerized olefin monomer, said main polymer core being overpolymerized with a copolymer comprising a major proportion of a polymerized acrylate and from about one to 40 percent by weight of a polymerized olefinic unsaturated nitrile. A two-step method for preparing such a latex also is described. The latices of the invention are useful in forming films at low temperatures, and the minimum film forming temperature can be regulated by the selection of the particular components and the relative amounts of the components used to form the latices.
    Type: Grant
    Filed: December 20, 1982
    Date of Patent: March 12, 1985
    Assignee: The Standard Oil Company
    Inventors: June T. Duke, Herbert F. Mazeke, Dorothy C. Prem
  • Patent number: 4450254
    Abstract: The impact resistance of high nitrile thermoplastic resins is greatly improved by including metal carboxylate compounds therein. Examples of metal carboxylate compounds useful herein include calcium stearate, calcium pelargonate, calcium laurate, zinc laurate, zinc stearate, aluminum distearate, aluminum laurate and aluminum pelargonate.
    Type: Grant
    Filed: June 25, 1982
    Date of Patent: May 22, 1984
    Assignee: Standard Oil Company
    Inventors: Ralph E. Isley, Dorothy C. Prem, June T. Duke
  • Patent number: 4351756
    Abstract: The inclusion of a small amount of an ester-type plasticizer in the rubber polymerization recipe in the production of rubber-modified high nitrile copolymer resins produces resins having markedly improved impact resistance at both low and high temperatures.
    Type: Grant
    Filed: June 2, 1980
    Date of Patent: September 28, 1982
    Assignee: SOHIO
    Inventors: Dorothy C. Prem, June T. Duke, Ralph E. Isley
  • Patent number: 4244852
    Abstract: The inclusion of a small amount of an ester-type plasticizer in the rubber polymerization recipe in the production of rubber-modified high nitrile copolymer resins produces resins having markedly improved impact resistance at both low and high temperatures.
    Type: Grant
    Filed: November 16, 1978
    Date of Patent: January 13, 1981
    Assignee: The Standard Oil Company
    Inventors: Dorothy C. Prem, June T. Duke, Ralph E. Isley
  • Patent number: 4163766
    Abstract: Impact-resistant polymers having low permeability to gases and vapors and excellent thermal color stability are prepared by polymerizing an olefinic nitrile, such as acrylonitrile, optionally with an olefinic ester, such as methyl acrylate, in an aqueous medium in the presence of an elastomer which is a copolymer of an ester of an olefinically unsaturated monocarboxylic acid, such as ethyl acrylate.
    Type: Grant
    Filed: June 19, 1978
    Date of Patent: August 7, 1979
    Assignee: The Standard Oil Company
    Inventors: June T. Duke, Dorothy C. Prem
  • Patent number: 4127614
    Abstract: Impact-resistant polymers having low permeability to gases and vapors and excellent thermal color stability are prepared by polymerizing an olefinic nitrile, such as acrylonitrile, optionally with an olefinic ester, such as methyl acrylate, in an aqueous medium in the presence of an elastomer which is a copolymer of an ester of an olefinically unsaturated monocarboxylic acid, such as ethyl acrylate.
    Type: Grant
    Filed: July 28, 1976
    Date of Patent: November 28, 1978
    Assignee: The Standard Oil Company
    Inventors: June T. Duke, Dorothy C. Prem
  • Patent number: 4079101
    Abstract: A polymerization process is described in which conjugated diolefin polymers are prepared by free-radical polymerization at improved rates by conducting the polymerization in a batch charge of all ingredients in aqueous emulsion in the presence of some preformed seed polymer having small particle size.
    Type: Grant
    Filed: September 2, 1975
    Date of Patent: March 14, 1978
    Assignee: The Standard Oil Company
    Inventors: June T. Duke, Dorothy C. Prem