Process for producing cyclic olefin based polymers, cyclic olefin copolymers, compositions and molded articles comprising the copolymers
CA 2070654 C · Owner: Maezawa, Hiroshi · Inventors: Okamoto, Takuji; Maezawa, Hiroshi; Watanabe, Masami
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for effectively producing a cyclic olefin polymer and a cyclic olefin/alpha-olefin copolymer without opening the cyclic olefin, is disclosed. Further a novel cyclic, olefin/alpha-olefin copolymer prepared by the above-mentioned process, compositions and molded articles comprising the novel copolymer, are also disclosed. In the process for producing a cylcic olefin based polymer according to the present invention homopolymerization of a cyclic olefin or copolymerization of a cyclic olefin and an alpha-olefin is effected in the presence of a catalyst comprising, as main ingredients the following, Compounds (A) and (B), and optionally Compound (C): (A) a transition metal compound;, …
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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 October 3, 1991 and granted June 3, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 3, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 3, 2013.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.