Polymerization process for olefin copolymers using bridged hafnocene compounds
CA 2318246 A1 · Owner: Exxonmobil Chemical Patents Inc. · Inventors: Schiffino, Rinaldo S.; Walzer, John F. Jr.; Folie, Bernard J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention is a polymerization process for ethylene copolymers having a density less than 0.915 comprising contacting ethylene one or more .alpha.-, olefin monomer, and optionally one or more diene monomer with a catalyst , composition comprising the reaction product of at least one organometallic Group 4 metallocene compound derived from a bridged fused-ring ligand , containing biscyclopentadienyl hafnocene said bridge being a substituted or , unsubstituted carbon or silicon atom connecting the biscyclopentadienyl ligands, and a salt of a Group 13 element anionic complex having halogenated aromatic ligands in an essentially tetrahedral structure wherein the aromatic groups 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 March 4, 1999. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended March 4, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 4, 2021.
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Timeline
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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.