Capped polyphenylene ethers
CA 2033847 A1 · Owner: Huls Aktiengesellschaft · Inventors: Kowalczik, Udo; Bartmann, Martin
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Capped polyphenylene ethers or mixtures thereof prepared by reacting polyphenylene ethers composed of the following units, wherein Q1 and Q2 are hydrocarbyl radicals having 1 to 10 carbon atoms, Q3 and Q4 are hydrogen or hydrocarbyl radicals having 1 to 10 carbon atoms with from about 0.5 to about 10% by weight relative to the polyphenylene ethers, of imides of the general formula, , and/or, wherein R1 is aromatic or saturated aliphatic radical having 1 to 20 carbon atoms, R2 and R3 are aromatic or saturated aliphatic radical having 1 to 12 carbon atoms, R4 is (CH2)m where m is from 3 to 11 and n is from 1 to 3. The reaction is carried out at a temperature of from 230° to 330°C, preferably …
Read the whole patent
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 January 9, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended January 9, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 9, 2013.
- 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.