Patents by Inventor John M. Donshak

John M. Donshak 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).

  • Reduction of acidity of polyesters by melt reaction endcapping with an alkylacetylacetonate
    Patent number: 5242993
    Abstract: A method for the melt reaction of polyesters, particularly polyethylene terephthalate, with an alkylacetylacetonate endcapping agent which reacts with terminal carboxyl groups of the polyester to produce polyesters having reduced acidity and PET products produced by the method having reduced acid content.
    Type: Grant
    Filed: February 4, 1991
    Date of Patent: September 7, 1993
    Assignee: Bridgestone/Firestone, Inc.
    Inventors: William L. Hergenrother, John M. Donshak