Process for preparation of polyarylene thioethers having high melt crystallization temperature
CA 1261537 A · Owner: Kureha Kagaku Kogyo Kabushiki Kaisha · Inventors: Kouyama, Toshitaka; Iwasaki, Takao; Iizuka, Yo
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Polyarylene thioethors having increased melt crystallization temperature are produced by subjecting a polyarylene thioether recovered from a conventional polycondensation of dichlorobenzene with sodium sulfide to a treatment with solution of a salt of a strong acid such as HCl H2SO4, or H3PO4 with a weak base such as ammonia. By the post-polycondensation treatment, the melt crystallization temperature can be increased. The polyarylene thioethers are used among, others, in injection molding.
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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 September 26, 1989. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended September 26, 2006.
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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.