Preparation of polyphenylene ethers
CA 1204248 A · Owner: Basf Aktiengesellschaft · Inventors: Rieber, Norbert; Naarmann, Herbert; Hambrecht, Juergen
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 high molecular weight polyphenylene ethers from monohydric phenols which have alkyl substituents in both ortho-positions and may additionally have an alkyl substituent in one meta-position but not in the para-position by an oxidative coupling reaction, employing oxygen at, from 10 to 25°C, in the presence of a catalyst complex comprising a copper salt and an N-substituted imidazole in the presence of an aromatic C8-C10-hydrocarbon solvent. N-Methylimidazole, N-ethylimidazole N-isopropyl-, imidazole, N-n-butylimidazole N-cyclohexylimidazole, N-octylimidazole and N-phenylimidazole are preferably used as the imidazole, advantageously in amounts of from 0.5 to 5 …
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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
- Granted May 6, 1986. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended May 6, 2003.
- 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
Timeline From CIPO dates
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.