Patents by Inventor Timothy Walter Wiwchar

Timothy Walter Wiwchar 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).

  • Polymer control through co-catalyst
    Patent number: 6825293
    Abstract: Some properties such as dart impact strength, hexane extractables and resin stickiness of a polyethylene copolymer produced in a gas phase polymerization using a Ziegler-Natta catalyst are better controlled by regulating the ratio of aluminum from the co-catalyst to the polymer production rate. This enables one to improve properties such as dart impact strength and reduce hexane extractables by changing the amount of co-catalyst fed into the reactor.
    Type: Grant
    Filed: August 20, 2001
    Date of Patent: November 30, 2004
    Assignee: Nova Chemicals (International) S.A.
    Inventors: Shivendra Kumar Goyal, Timothy Walter Wiwchar, Victoria Ker, Mark Kelly