Production of granular poly(arylene sulfide) polymers containing reduced amounts of oligomers
CA 2103628 A1 · Owner: Clark, Earl Jr. · Inventors: Scoggins, Lacey E.; Clark, Earl Jr.; Kile, Glenn F.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method for removing oligomers and non-polymeric impurities from poly(arylene sulfide) polymers and producing the polymers in easily recoverable granular form is provided in which a poly(arylene sulfide) polymer associated with oligomers and non-polymeric impurities is contacted with a solvent, water, and optionally a base, at a sufficient, temperature to substantially dissolve the polymer oligomers and, impurities; then the solution is cooled to a temperature at which the poly(arylene sulfide) precipitates while oligomers and impurities remain in solution, then the precipitated polymer is separated from the solution containing the oligomers and impurities. A polymer product produced by …
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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 August 9, 1993. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended August 9, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 9, 2015.
- 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
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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.