Process and device for the gas-phase polymerisation of alpha-olefins
CA 2037175 A1 · Owner: Bp Chemicals Limited · Inventors: Raufast, Charles; Brule, Daniel; Iffly, Jean-Marie
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention relates to a process and a device for polymerizing alpha-olefins such as ethylene or propylene in a gas phase. The device comprises a gas phase polymerization reactor (5) into which a suspension of prepolymer particles in liquid saturated hydrocarbon(s) is continuously introduced. The prepolymer suspension is prepared in one or more prepolymerization vessels (14) and is continuously passed to a post-treatment unit comprising a degassing means (10) wherein most of the dissolved unreacted olefinic monomer(s) is separated. Preferably the post-treatment, unit may comprise a particle separation means (11) for removing the finest and/or coarsest prepolymer particles from the …
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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 February 27, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended February 27, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 27, 2013.
- 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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Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.