Maleimide copolymers and method for inhibiting hydrate formation
CA 2178364 C · Owner: Talley, Larry D. · Inventors: Oelfke, Russell H.; Berluche, Enock; Costello, Christine A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Novel maleimide copolymers have at least two monomeric units a maleimide unit and a, vinyl unit having a pendant group the pendant group having two to twenty-one carbon atoms at least one nitrogen atom and at least one oxygen atom. The copolymer has an average molecular weight between about 1,000 and about 6,000,000. Preferred maleimide copolymers include acrylamide/maleimide copolymers N-vinyl amide/maleimide copolymers, vinyl lactam/maleimide copolymers, alkenyl cyclic imino ether/maleimide copolymers and, acryloylamide/maleimide copolymers. The substantially water soluble maleimide copolymers are useful for inhibiting the formation of clathrate hydrates in a fluid having hydrate-forming …
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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 June 6, 1996 and granted September 26, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 6, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 6, 2018.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.