Patents by Inventor Eva F. Tai

Eva F. Tai 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 making aggregates or clusters of water-swellable polymers having increased hydration rate over unassociated water-swellable polymers
    Patent number: 5374684
    Abstract: Clusters of water-swellable polymer particles, having high rates of absorbency without gel-blocking are prepared by suspending water-swellable polymer particles in an inert hydrophobic liquid, such as hydrocarbon, and slowly adding to the particles a suspension of an aqueous solution optionally containing an .alpha.,.beta.-ethylenically unsaturated monomer in an inert hydrophobic liquid.
    Type: Grant
    Filed: September 1, 1993
    Date of Patent: December 20, 1994
    Assignee: The Dow Chemical Company
    Inventor: Eva F. Tai
  • Regeneration and extension of lifetime of dehydrogenation catalysts used in the preparation of 2-alkylpyrimidines
    Patent number: 5180700
    Abstract: The useful life of the palladium dehydrogenation catalyst used in the preparation of 2-alkylpyrimidines from 1,3-diaminopropane and an appropriate alkanecarboxylic acid in a continuous vapor phase process is substantially increased by employing a stoichiometric excess of the carboxylic acid and by using catalyst pellets of less than 3-4 mm diameters. Additionally, the dehydrogenation catalyst can be regenerated in situ by controlled air oxidation below 350.degree. C.
    Type: Grant
    Filed: May 13, 1991
    Date of Patent: January 19, 1993
    Assignee: DowElanco
    Inventors: Eva F. Tai, John W. Hull, Jr., Kenneth E. First