Process for efficient molecular weight control in copolymerization
CA 2022705 C · Owner: Swift, Graham · Inventors: Swift, Graham; Hughes, Kathleen A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention relates to copolymers containing as copolymerized monomer units aliphatic monoethylenically unsaturated dicarboxylic acids such as malefic acid, monoethylenically unsaturated monocarboxylic acids such as acrylic acid and carboxyl-free monoethylenically unsaturated monomers such as alkyl esters of acrylic acid. This inventian particularly relates to the use of low levels of copper ions in an aqueous emulsion polymerization process to promote copolymerization of the above-mentioned monomers at high conversion while maintaining and improving molecular weight control. These copolymers are useful primarily as antiscalants dispersants, hard, surface cleaners, detergent builders and …
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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 3, 1990 and granted May 29, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 3, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 3, 2012.
- 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.