Improved cationic polymerization process and catalyst system therefor
CA 2257701 A1 · Owner: Ismeier, Juergen R. · Inventors: Ismeier, Juergen R.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for producing a copolymer of an isoolefin and at least one other comonomer comprising the step of polymerizing a reaction mixture comprising an isoolefin, a catalyst and at least one of a cycloconjugated multiolefin and an unconjugated, cyclic olefin in the presence of an activator comprising a carbo cation producing species, a silica cation producing species and mixtures thereof. The process can be practiced, using a solution polymerization approach or a slurry polymerization approach. One of the, main benefits achieved with the present invention is the conversion of the monomers over, a shorter period of time and higher percent conversion than when the activator is not, …
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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 31, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended December 31, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 31, 2020.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
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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.