Patents by Inventor Peter Sefton Williams

Peter Sefton Williams 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 the polymerization of olefins in the gas phase
    Patent number: 6437060
    Abstract: A process for the polymerisation of olefins in the gas phase is carried out in the presence of a supported transition metal catalyst. The process involves a prepolymerisation step which may be performed in-situ and in particular the prepolymer may be prepared in the dry phase. The catalyst may for example comprise a constrained geometry transition metal complex supported on silica and used in the presence of an activator. The prepolymerisation step enables the activity of the catalyst to be improved.
    Type: Grant
    Filed: December 23, 1999
    Date of Patent: August 20, 2002
    Assignee: BP Chemicals Limited
    Inventors: Peter James Maddox, Peter Sefton Williams
  • Gas phase olefin polymerization process
    Patent number: 6437062
    Abstract: A process for the polymerization of olefins in a gas phase reactor operating in a non-condensed mode, in which the process is carried out in the presence of a catalyst system containing (a) a metallocene supported on a solid support and (b) an activator, and adding a lower alkane to the gas phase reactor.
    Type: Grant
    Filed: July 9, 1999
    Date of Patent: August 20, 2002
    Assignee: BP Chemicals Limited
    Inventors: Peter James Maddox, Peter Sefton Williams