Process for making polyolefins
CA 2391327 A1 · Owner: Equistar Chemicals, L.P. · Inventors: Cribbs, Leonard V.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A two-step olefin polymerization process is disclosed. A single-site catalyst precursor reacts with a boron-containing activator and a first olefin substantially in the absence of an alumoxane to produce a stable prepolymer , complex, which is then used to polymerize a second olefin in the presence of a scavenging amount of an alumoxane. The process gives high molecular weight polyolefins with low residual aluminum contents. Boron-containing activators can be used, even at reaction temperatures greater than 100 ~C while , maintaining high catalyst activity.
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 August 10, 2000. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended August 10, 2020.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 10, 2022.
- 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.