Patents by Inventor Gary A. Hida

Gary A. Hida 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).

  • Polymerization of tetrahydrofuran using trifluoromethane sulfonic acid monohydrate as catalyst
    Patent number: 5155283
    Abstract: A process for forming polytetramethylene ether glycol having a number average molecular weight of 600 to 2,200 by contacting tetrahydrofuran with 5 to 50 wt %, based on tetrahydrofuran, trifluoromethane sulfonic acid monohydrate and water at 20.degree. to 75.degree. C. is disclosed.
    Type: Grant
    Filed: July 19, 1991
    Date of Patent: October 13, 1992
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Suriyanarayan Dorai, Gary A. Hida
  • Polymerization of tetrahydrofuran using a fluorinated acidic catalyst and maleic acid/maleic anhydride mixture as molecular weight control agent
    Patent number: 5130470
    Abstract: A process for polymerizing tetrahydrofuran using a fluorinated resin containing sulfonic acid groups a trifluoromethane sulfonic acid as catalyst and a mixture of maleic acid and maleic anhydride as weight control agent. The product has the formula ##STR1## which can be hydrogenated to produce polytetramethylene ether glycol. The preferred molecular weight range of the polytetramethylene ether glycol is 600 to 4,000.
    Type: Grant
    Filed: March 27, 1991
    Date of Patent: July 14, 1992
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Suriyanarayan Dorai, Willard L. Quon, Kirk M. Schall, Gary A. Hida