Process for alpha-olefin gas-phase polymerization controlled by the simultaneous addition of an activator and an activity retarder to the polymerization medium
CA 2006083 C · Owner: Bp Chemicals Limited · Inventors: Bernard, Jean-Claude; Berruyer, Claudine; Havas, Laszlo
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for controlling the continuous gas-phase polymerisation of one or more alpha-olefins in a fluidized and/or mechanically stirred bed reactor using a high activity catalyst based on a transition metal of groups IV V or VI of the Periodic, Table comprises introducing into the reactor continuously and, simultaneously, an activity retarder and an activator in very small, amounts, in a molar ratio and at flow rates which are varied with time in order to maintain substantially constant either the polymerization rata or the transition metal content of the polymer produced.
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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 December 20, 1989 and granted September 28, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 20, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 20, 2011.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.