Solid state devolatilization of syndiotactic vinyl aromatic polymers with catalyst deactivation
CA 2284803 A1 · Owner: The Dow Chemical Company · Inventors: Billovits, Gerald F.; Tipler, Scott A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention is an improved solid state polymer devolatilization process which comprises heating a wet feed mixture comprising polymer residual monomer(s), process solvents and active catalyst residues in the presence of an inert gas, wherein the improvement comprises replacing the inert gas with a catalyst desactivating gas.
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 30, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended January 30, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 30, 2020.
- 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.