Acrylic trisequenced copolymers; process for preparing the same and their use for manufacturing elastomeric articles
CA 2063415 C · Owner: Varshney, Sunil K. · Inventors: Hautekeer, Jean-Paul; Varshney, Sunil K.; Teyssie, Philippe
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention involves a trisequenced copolymer A-B-C, which has a MW of from 3,000 to 300,000 and a polydispersity of 1.05 to 2Ø A and C each represent an acrylic vinylaromatic, methacrylic or maleimide sequence; B represents an acrylic vinylaromatic or methacrylic sequence; at least one of A and C is chosen from a different class than that of block B. To prepare this copolymer at least one monomer, A, is anionically polymerized using an initiator consisting of at least one monofunctional initiator (R)p-M (M = alkali metal or alkali earth p = valence of M, and R = C2-6 alkyl or C1-6 alkyl substituted by at least one phenyl group) and at least one ligand (alkali metal salt or alkali earth …
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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 July 5, 1990 and granted January 5, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 5, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 5, 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.