Patents by Inventor Jia-Chu X. Liu

Jia-Chu X. Liu 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).

  • Supported olefin polymerization catalysts
    Patent number: 6211311
    Abstract: A supported olefin polymerization catalyst system and a method of making it are disclosed. The catalyst system comprises: (a) a support chemically treated with an organoaluminum, organosilicon, organomagnesium, or organoboron compound; (b) a single-site catalyst that contains a polymerization-stable, heteroatomic ligand; and (c) an activator. Chemical treatment is a key to making supported heterometallocenes that have high activity and long shelf-lives, and can effectively incorporate comonomers.
    Type: Grant
    Filed: May 25, 1999
    Date of Patent: April 3, 2001
    Assignee: Equistar Chemicals, L.P.
    Inventors: Shaotian Wang, Bradley P. Etherton, Karen E. Meyer, Michael W. Lynch, Linda N. Winslow, Leonard V. Cribbs, Jia-Chu X. Liu
  • Single-site catalyst preparation
    Patent number: 6020493
    Abstract: An improved method of making an olefin polymerization catalyst is disclosed. The method reacts essentially equimolar amounts of a Group 4 transition metal tetrahalide and a quinolinol or pyridinol in the presence of a C.sub.5 -C.sub.10 hydrocarbon at a temperature within the range of about 0.degree. C. to about 60.degree. C. The method gives high yields of quinolinoxy or pyridinoxy-substituted Group 4 transition metal trihalides in a single reaction step. Particularly when combined with an activator, the target compounds are excellent olefin polymerization catalysts.
    Type: Grant
    Filed: May 6, 1999
    Date of Patent: February 1, 2000
    Assignee: Equistar Chemicals, LP
    Inventor: Jia-Chu X. Liu