A process for the preparation of copolymers
CA 2246749 A1 · Owner: Shell Internationale Research Maatschappij B.V. · Inventors: Jubb, Jayne; Baardman, Frank
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for the preparation of copolymers of carbon monoxide with an olefinically unsaturated compound comprising copolymerizing the monomers in the presence of a catalyst composition based upon (a) a salt of a Group VIII metal, and (b) a cation which is selected from cationic oxidants and cations of the general formulae RnH4-nN+, RmH3-mC+ and RmH3-mO+ wherein n is 0, 1, 2, 3 or 4, m is 2 or 3 and R represents a hydrocarbyl group and/or two or three of R together with the atom carrying a positive charge represent a ring structure comprising carbon atoms in the ring on the understanding that when , n is 3 at most two of R together with nitrogen represent a heterocyclic ring …
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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, 1997. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended February 27, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 27, 2019.
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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.