Intervulcanized elastomer blends
CA 2172964 A1 · Owner: Wang, Hsien-Chang · Inventors: Wang, Hsien-Chang
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Intervulcanized compositions having improved curing efficiency are prepared by the free radical curing of a mixture of an ethylenically unsaturated diolefin polymer such as natural or synthetic rubber and a saturated or low unsaturation polymer such as an isobutylene/para-methylstyrene copolymer which contains functional groups pendant to the polymer chain. These functional groups contain an olefinic or vinyl double bond positioned alpha beta to a , substituent group which activates the double bond towards free radical addition reactions with the diolefin polymer. Preferred functionality includes benzylic ester functionality represented by structure (1) wherein R2 and R3 , are …
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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 September 26, 1994. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended September 26, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 26, 2016.
- 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.