Preparation of a non-linear, elastomeric copolymer
CA 1067643 A · Owner: Shell Canada Limited · Inventors: Vreugdenhil, Arie D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Non-linear solution diene rubbers, e.g. SBR, obtain improved green strength, if less than 30% of the polymer chains is "capped" with a polystyrene block having a mol. weight of e.g. 20,000. They are, obtained by coupling polymer blocks B'-Li and A-B-Li in a molar ratio of at least 2.5 with an at least trifunctional coupling agent wherein, A is a polymer block of a monoalkenyl or monoalkenylidene aromatic hydrocarbon having an average molecular weight between 5,000 and 35,000 B and B' are polymer blocks substantially comprising polymerized conjugated diene molecules. These rubbers exhibit an improved green strength whilst retaining adequate processability and satisfactory properties after …
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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
- Granted December 4, 1979. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended December 4, 1996.
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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.