Process for the preparation of oxymethylene polymers
CA 1113641 A · Owner: Hoechst Aktiengesellschaft · Inventors: Schlaf, Helmut; Burg, Karlheinz
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Oxymethylene polymers are prepared by polymerization of trioxane, optionally in the presence of comonomers, with the acid of a cationically active initiator. Suitable initiators are salt-like compounds, especially onium salts of Lewis acids. The initiator is used in the form of a solution in a cyclic carbonic acid ester present in a liquid phase. The oxymethylene polymers are thermoplastic and may be used as engineering materials.
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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 1, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended December 1, 1998.
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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.