Preparation of bead polymers from water-soluble, ethylenically unsaturated monomers
CA 1296475 C · Owner: Heide, Wilfried · Inventors: Niessner, Manfred; Peters, Karl-Clemens; Hartmann, Heinrich
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Polymers in bead form are prepared from water-soluble ethylenically unsaturated monomers by a reverse suspension polymerization of an aqueous solution of the monomers in an inert hydrophobic liquid in the presence of polymerization initiators and protective colloids obtainable by grafting polymers A) containing, a) from 40 to 100% by weight of an aromatic monovinyl monomer, b) from 0 to 60% by weight of a monoethylenically unsaturated carboxylic acid of 3 to 6 carbon atoms and/or maleic anhydride and, c) from 0 to 20% by weight of other monoethylenically unsaturated monomers, as copolymerized units with the proviso that the sum of the weight percentages (a) to (c) is always 100 and 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
- Granted February 25, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 25, 2009.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.