Process for grafting vinyl monomers on particulate olefin polymers
CA 2071650 C · Owner: Himont Incorporated · Inventors: Smith, Jeanine A.; Galli, Paolo; Guhaniyogi, Suhas C.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention provides a uniformly grafted particulate polyolefin material formed by the free radical-initiated grafting of at least one non-homopolymerizing vinyl monomer at free radical sites on a particulate olefin polymer material having (a) a pore volume fraction of at least about 0.07 wherein more than 40% of the pores have a diameter larger than 1 micron; and (b) a weight average diameter in the range of about 0.9 to 7 mm. The amount of vinyl monomer grafted to the as-polymerized particulate olefin polymer material is about 0.1 to 10%, preferably about 0.3 to 5.0% of the total weight of the grafted olefin polymer product and the, grafted vinyl monomer is uniformly distributed …
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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 June 19, 1992 and granted April 29, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 19, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 19, 2014.
- 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.