The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 14, 2003
Filed:
Nov. 29, 1999
Vidar Almquist, Stathelle, NO;
Paul Allemeersch, Stathelle, NO;
Roger Goris, Stathelle, NO;
Ann Kristin Lindahl, Stathelle, NO;
Borealis Technology Oy, , FI;
Abstract
Ths invention provides a process for the preparation of a polyethylene, in particular an HDPE suitable for blow moulding of HIC, which comprises polymerizing ethylene and, optionally an ethylenically unsaturated comonomer copolymerizable therewith, in the presence of a catalyst comprising a first silica-supported chromium catalyst having a pore volume of at least 2 mL/g, a surface area of at least 350 m /g and a chromium content of 0.1 to 1.0% by weight and a second silica-supported chromium catalyst having a pore volume of at least 2 mL/g, a surface area of at least 450 m /g and a chromium content of 0.1 to 1.0% by weight, wherein the silica support of said first catalyst also comprises alumina and the silica support of said second catalyst also comprises titanium, and preferably a co-catalyst.