Patents by Inventor John D. Hand

John D. Hand 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).

  • Solution process for the preparation of polyimides from diamines and anhydrides
    Patent number: 3996203
    Abstract: Novel polyimide prepolymers with improved mold flow characteristics and enhanced physical properties when thermoset, are provided by heating a difunctional amine and an anhydride of an unsaturated dicarboxylic acid in a solvent at a temperature not in excess of 75.degree. C. until all of the amine groups are reacted, then, without isolating the reaction product, heating it with more difunctional amine in a solvent at a temperature not in excess of 75.degree. C. until formation of a prepolymer is substantially complete.
    Type: Grant
    Filed: July 15, 1974
    Date of Patent: December 7, 1976
    Assignee: General Electric Company
    Inventors: John D. Hand, Wendell G. Whitehouse