Epoxy-catalyst additive system to produce higher i.v. polybutylene terephthalate from low i.v. polymer
CA 1083295 A · Owner: Celanese Corporation · Inventors: Thomas, Norman W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention provides a process for preparing branched chain, thermoplastic polymers having improved melt strength and die swell properties. This process comprises reacting at least one thermoplastic polymer capable of reaction with an epoxy functionality with at least one epoxy, branching agent containing at least two epoxy groups per molecule of epoxy branching agent in the molten state in the presence, of a catalytic amount of at least one catalyst. The catalyst may be selected from the group consisting of alkyl triphenyl phosphonium halide and alkenyl triphenyl phosponium halide wherein the alkyl groups contain from one to ten carbon atoms the alkenyl groups contain from two to …
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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 August 5, 1980. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended August 5, 1997.
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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.