Process for preparing tetrafluoroethylene-ethylene copolymers
CA 2003054 C · Owner: Monti, Claudio · Inventors: Monti, Claudio
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 a process for preparing copolymers of tetrafluoroethylene with ethylene and, optionally, with a third monomer, of vinylic character. The process is characterized in that tetrafluoroethylene is reacted with ethylene and optionally, with a third, vinylic monomer in an aqueous emulsion with the aid of a polymerization initiator of the peroxy type. The reaction is conducted at a temperature in the range of from 30 to 95°C and under a pressure in the range of from 1.5 to 4.0 MPa in the, presence of t-butyl alcohol and of 1,1,2,2-tetrachloro-1,2-difluoro-ethane.
Read the whole patent
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 November 15, 1989 and granted June 8, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 15, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 15, 2011.
- 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.