Two-step thermal process for the preparation of alkenyl succinic anhydride
CA 2119011 A1 · Owner: Harrison, James J. · Inventors: Harrison, James J.; Ruhe, William R. Jr.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for the preparation of an alkenyl-substituted succinic anhydride wherein the alkenyl substituent has a number average molecular weight of from about 500 to 5000 and the average number of succinic groups per alkenyl group is greater than 1.2 which comprises: (a) reacting a polyolefin having an alkylvinylidene isomer content of less than about 10 percent and a number average molecular weight of about 500 to 5000 with maleic anhydride at a temperature in the range of about 200 ·C to 250 ·C to provide a mixture of alkenyl succinic anhydride having an average of about 1.0 succinic group per alkenyl group and unreacted polyolefin and (b), reacting the mixture of alkenyl succinic …
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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 July 23, 1993. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended July 23, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 23, 2015.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.