Patents by Inventor Seung T. Cheung

Seung T. Cheung 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).

  • Rubber compositions
    Patent number: 4779657
    Abstract: An improved rubber composition for use in articles requiring reduced permeability to air, comprises:one hundred parts by weight of a terpolymer of isobutylene, isoprene and .alpha.-methylstyrene,from about 30 to about 90 parts by weight of at least one carbon black, anda curing system,wherein the terpolymer comprises from about 0.5 to about 2 mole percent of isoprene, from about 2 to about 7 mole percent of .alpha.-methylstyrene and from about 91 to about 97.5 mole percent of isobutylene.
    Type: Grant
    Filed: December 28, 1987
    Date of Patent: October 25, 1988
    Assignee: Polysar Limited
    Inventors: Seung T. Cheung, Richard S. Steevensz