Patents by Inventor Wen-Shien Yang

Wen-Shien Yang 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).

  • Process for selective hydrogenation of conjugated diene polymer
    Patent number: 5705571
    Abstract: The present invention provides a process for selective hydrogenation of a conjugated diene polymer. The process includes bringing the conjugated diene polymer in an inert organic solvent into contact with hydrogen in the presence of a specific hydrogenation catalyst combination including (A) a substituted or unsubstituted bis(cyclopentadienyl) Group VIII transition metal compound and (B) an organic lithium compound. The hydrogenation can be carried out in the presence of a small amount of the hydrogenation catalyst combination under mild conditions, and both the hydrogenation conversion and selectivity to conjugated diene units are high.
    Type: Grant
    Filed: June 25, 1996
    Date of Patent: January 6, 1998
    Assignee: Taiwan Synthetic Rubber Corporation
    Inventors: Raymond Chien-Chao Tsiang, Henry Chi-Chen Hsieh, Wen-Shien Yang