Patent US4750431A successfully refreshed from Google Patents.
Patent EP0171199A2 successfully refreshed from Google Patents.
EP0171199A2
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Crystalline polypropylene sheet
Assignee: Sumitomo Chemical Co Ltd
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Filing: 1985-07-09
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Granted: —
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Expires: 2005-07-09
Abstract
Abstract A crystalline polypropylene sheet contains a polymer of a vinylcycloalkane having at lesst 6 carbon atoms in an amount of 0.05 wt ppm to 1 wt% (calculated as a vinylcycloalkane unit). This sheet is excellent in stiffness and transparency and is suitable for use in the production of articles such as containers and tray.The cycloalkane is produced by polymerization in the presence of a Ziegler-Natta catalyst and is mixed with propylene homopolymer or with a propylene/a-olefin copolymer, and optionally with another polymer; pellets of the mixture are extruded.
Inventors
- 👤 Masahiro Kakugo
- 👤 Yoshiharu Fukui
- 👤 Kizuku Wakatsuki
- 👤 Hideaki Nishio
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 20:13
CPC Classifications
C; C08; C08L; C08L23/00; C08L23/02; C08L23/10; C08L23/12; C08L23/14; C08L23/142; C08F; C08F210/00; C08F210/04; C08F210/06; C08L23/18; C08L23/20; C08L2314/00; C08L2314/02
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
31 words
A crystalline polypropylene sheet containing a polymer of a vinylcycloalkane having at least 6 carbon atoms in an amount of 0.05 wt ppm to 1 wt% calculated as a vinylcycloalkane unit.
Claim 2
Dependent Claim
31 words
A crystalline polypropylene sheet containing a polymer of a vinylcycloalkane having at least 6 carbon atoms in an amount of 0.05 wt ppm to 1 wt% calculated as a vinylcycloalkane unit.
Claim 3
Dependent Claim
29 words
A crystalline polypropylene sheet as claimed in Claim 1, wherein the amount of the polymer of the vinylcycloalkane is 0.5 to 5,000 wt ppm calculated as a vinylcycloalkane unit.
Claim 4
Dependent Claim
22 words
A crystalline polypropylene sheet as claimed in Claim 1 or 2,wherein the vinylcycloalkane is vinylcyclobutane-, vinylcyclopentane, vinyl-3-methylcyclopentane, vinylcyclohexane, vinyl-2-methylcyclohexane, vinyl-3-methylcyclohexane or vinylnorbornane.
References Cited (Backward Citations)
No citation records indexed.
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