A method for making selectively hydrogenated block copolymers of vinyl aromatic hydrocarbons and conjugated dienes
CA 2420357 A1 · Owner: Schisla, David K. · Inventors: Johnson, Kimberly Ann; De Jong, Wouter; Schisla, David K.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
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Disclosed is a method for making selectively hydrogenated block copolymers of vinyl aromatic hydrocarbons and conjugated dienes comprising: a) anionically polymerizing vinyl aromatic hydrocarbons and conjugated dienes to produce block copolymers with living chain ends; b) terminating the living chain ends to produce a terminated block copolymer with a member from the group , consisting of an alcohol hydrogen, and mixtures thereof, to prepare a terminated block copolymer; and c) contacting the terminated block copolymers with hydrogen at a temperature of from 20 to 175~ C in the presence of a catalyst prepared by combining a cobalt carboxylate with an aluminum alkyl wherein: (i) if the …
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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 24, 2001. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended August 24, 2021.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 24, 2023.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.