Process for preparing polyolefins having a bimodal molecular weight distribution
CA 2078777 C · Owner: Stricklen, Phil Marvin · Inventors: Stricklen, Phil Marvin
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A two-step polymerization process for producing a polyolefin having a bimodal molecular weight distribution is provided. In step one, under polymerization conditions at, least two different alpha olefins are contacted with a catalyst system which comprises a aluminoxane and a metallocene, selected from the group consisting of mono di, and tri-cyclopentadienyls and substituted cyclopentadienyls of a metal selected from titanium, vanadium chromium, zirconium, niobium, molybdenum hafnium, tantalum, and, tungsten, provided however if said metal is titanium then a metallocene of at least one other of said metals is present such that a first polymerization mixture is formed which comprises a low …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed March 3, 1992 and granted September 29, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 3, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 3, 2014.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.