Process for the preparation of siloxane-oxyalkylene copolymers
CA 1290886 C · Owner: Lehew, Richard A. · Inventors: Austin, Paul E.; Reedy, James D.; Farris, David D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An improved process is provided for the preparation of siloxane-oxyalkylene copolymers by a solventless process via hydrosilation of oxyethylene-rich polyethers in the presence of carboxylic acids or carboxylic acid salts as a catalyst modifier. The use of a carboxylic acid or salt prevents acetal formation through the hydroxyl groups of the polyether and/or copolymer. The use of solvent, acetal treatment and solvent stripping steps of the conventional processes are eliminated and accordingly, environmental as well as economic benefits are achieved.
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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
- Granted October 15, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended October 15, 2008.
- 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.