Cycloolefin (co)polymers with a narrow molecular weight distribution and a process for the preparation thereof
CA 2061869 A1 · Owner: Hoechst Aktiengesellschaft · Inventors: Osan, Frank; Brekner, Michael-Joachim
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract of the disclosure Cycloolefin (co)polymers with a narrow molecular weight distribution and a process for the preparation thereof Polymers of polycyclic olefins such as for example, norbornene or tetracyclododecene or copolymers of, polycyclic olefins with cycloolefins and/or 1-olefins with a very narrow molecular weight distribution are obtained without ring opening by a polymerization in which a catalyst which is composed of an aluminoxane and of a stereorigid, chiral metallocene compound of an element of groups IVb to VIb is used, and in which the reaction is stopped at a time when the molecular weight distribution Mw/Mn of the polymer formed is < 2.
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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 26, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended February 26, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 26, 2014.
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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.