Patents by Inventor Rita S. McMinn

Rita S. McMinn 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: 5464904
    Abstract: Copolymers of tetrafluoroethylene (TFE) and hexafluoropropylene (HFP) having high HFP content and end-of-melting temperature, T.sub.m (end), as low as 200.degree. C. are disclosed. Exceptional performance as a processing aid in polyolefins results from having T.sub.m (end) of the TFE/HFP copolymer close to the processing temperature of the polyolefin. These TFE/HFP copolymers are soluble in fluorinated cyclic solvents. Copolymer/solvent systems copolymer at significant concentrations in selected solvents are fluid and stable at room temperature.
    Type: Grant
    Filed: November 16, 1994
    Date of Patent: November 7, 1995
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: George R. Chapman, Jr., Lewis E. Crenshaw, Rita S. McMinn, Richard A. Morgan, Donnan E. Priester, Charles W. Stewart, Robert E. Tarney
  • Patent number: 5266639
    Abstract: Copolymers of tetrafluoroethylene (TFE) and hexafluoropropylene (HFP) having high HFP content and end-of-melting temperature, T.sub.m (end), as low as 200.degree. C. are disclosed. Exceptional performance as a processing aid in polyolefins results from having T.sub.m (end) of the TFE/HFP copolymer close to the processing temperature of the polyolefin. These TFE/HFP copolymers are soluble in fluorinated cyclic solvents. Copolymer/solvent systems copolymer at significant concentrations in selected solvents are fluid and stable at room temperature.
    Type: Grant
    Filed: August 28, 1992
    Date of Patent: November 30, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: George R. Chapman, Jr., Lewis E. Crenshaw, Rita S. McMinn, Richard A. Morgan, Donnan E. Priester, Charles W. Stewart, William H. Tuminello, Robert E. Tarney, John G. Van Alsten, Mark E. Wagman
  • Patent number: 5089200
    Abstract: Process of melt extruding through an extrusion die whose surface is coated with one or more metal oxides, M.sub.x O.sub.y, wherein M is a metal selected from the group consisting of Ti, Zr, Cr, Fe, Ni, Pd, Pt, Cu, Ag, Au, Al and Si, and x and y are selected to satisfy the valencies of M, a difficultly-melt-processible polymer containing 0.002-2 parts by weight, based on the weight of the polymer, of at least one melt-processible fluorocarbon polymer processing aid having a fluorine to carbon ratio of at least 1:2 and having metal oxide-reactive sites capable of reacting with or physically associating with the metal oxide of the die surface.
    Type: Grant
    Filed: September 20, 1990
    Date of Patent: February 18, 1992
    Assignee: E. I. DuPont de Nemours and Company
    Inventors: George R. Chapman, Jr., Rita S. McMinn, Donnan E. Priester, William L. Phillips