Uhmw polyethylene molding compositions from multistage polymerization
CA 1282518 C · Owner: Sano, Akira · Inventors: Oka, Masataka; Matsuura, Kazuo; Sano, Akira
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A molding composition is disclosed which comprises ultralhigh molecular weight polyethylene having an intrinsic viscosity of 10 - 30 d?/g at 135°C in decalin. Improved injection moldability is provided by the use of such polyethylene obtainable by a multi-stage polymerization reaction including at least the following two stages: (a) a first stage in which ethylene is polymerized using a specified composite catalyst in the absence of hydrogen or its presence at lower concentration to produce 50 - 99.5 weight parts of polyethylene having an intrinsic viscosity of 12 - 32 d?/g at 135°C in decalin; and (b) a second stage in which a fresh feed of ethylene is polymerized in the presence of …
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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 April 2, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended April 2, 2008.
- 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
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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.