Patents by Inventor Daniel R. Chisholm

Daniel R. Chisholm 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).

  • Method for preparing mercaptopropionic acid esters
    Patent number: 5157147
    Abstract: A process is provided for the preparation of mercaptopropionic acid esters by reaction of an acrylic acid ester with hydrogen sulfide in the presence of a weakly basic amine as a catalyst, a polyether as a co-catalyst, a polythiodipropionic acid ester as a reactive solvent, and added elemental sulfur.
    Type: Grant
    Filed: November 5, 1990
    Date of Patent: October 20, 1992
    Assignee: Witco Corporation
    Inventors: Daniel R. Chisholm, George A. Seubert, Jr.
  • 3-alkylthiopropionic acids and derivatives
    Patent number: 5057622
    Abstract: 3-alkylthiopropionic acids are provided which are a direct addition reaction product of an alkylmercaptan and acrylic acid of an alkali metal salt thereof, the reaction being carried out by heating the reactants in the presence of an aqueous alkaline solution having a pH of at least about 11. The acids can be esterified with pentaerythritol in order to form tetraesters which are especially useful as stabilizers for polymer resins and polymers.
    Type: Grant
    Filed: December 10, 1990
    Date of Patent: October 15, 1991
    Assignee: Witco Corporation
    Inventors: Daniel R. Chisholm, Michael H. Fisch, Mark E. Flanagan, Richard D. Peveler