Process for the preparation of polymeric foam materials
CA 1103850 A · Owner: Rohm G.M.B.H. · Inventors: Schroder, Gunter
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention relates to the preparation of foamable polymer materials which may be converted into polacrylimide and polymethacrylimido foam materials upon heating; The foamable polymer materials are prepared by a process which comprises radically polymerising a monomer composition comprising: A) acrylonitrile and/or methacrylonitrile and acrylic acid and/or methacrylic acid, the said nitrile(s) and acid(s) being employed in a molar ratio in the range 2:3 to 3:2; and if desired, B) up to, 20% (based on the weight of A) of at least one further radically polymerisable comonomer; the said monomer composition further containing as a propellant 1 to 15% (based on the weight of A) 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
- Granted June 23, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended June 23, 1998.
- 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.