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US5116540A
Expired / Lapsed
US
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Free-radical modified carbon black filled polypropylenes
Assignee: Vibrantz Corp
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Filing: 1989-03-03
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Granted: 1992-05-26
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Expires: 2009-03-03
Abstract
Abstract Peroxide-provided free-radical molecular weight distribution narrowing of polypropylenes in the compounding stage of making conductive polypropylenes yields carbon black filled polypropylenes with improved rheological properties, surface conductivity, appearance, and surface characteristics with mechanical and physical properties similar to prior conductive polypropylenes.
Inventors
- 👤 Deenadayalu Chundury
- 👤 Daniel L. Davidson
- 👤 Berdine L. Leonard
- 👤 Anthony S. Scheibelhoffer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 13:46
CPC Classifications
H; H01; H01B; H01B1/00; H01B1/20; H01B1/24; C; C08; C08K; C08K3/00; C08K3/02; C08K3/04; C08K5/00; C08K5/04; C08K5/14
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
84 words
A conductive polypropylene, comprising: from about 50 to about 90 percent by weight of polypropylene and from about 10 to about 50 percent of conductive carbon which may be in the form of one or more of fibers and spheres, said polypropylene and said carbon being in situ melt processed in the presence of an effective amount of a peroxide to provide a narrowed molecular weight distribution of said polypropylene, said effective amount being more than 0 up to about 5 percent by weight.
Claim 2
Dependent Claim
84 words
A conductive polypropylene, comprising: from about 50 to about 90 percent by weight of polypropylene and from about 10 to about 50 percent of conductive carbon which may be in the form of one or more of fibers and spheres, said polypropylene and said carbon being in situ melt processed in the presence of an effective amount of a peroxide to provide a narrowed molecular weight distribution of said polypropylene, said effective amount being more than 0 up to about 5 percent by weight.
Claim 3
Dependent Claim
17 words
The polypropylene of claim 1 comprising about 70% free-radical generator treated polypropylene and about 30% conductive carbon.
Claim 4
Dependent Claim
19 words
The polypropylene of claim 1 further comprising an amount of polybutylene or polybutene effective to enhance the resiliency thereof.
Claim 5
Dependent Claim
17 words
The polypropylene of claim 1 wherein the conductive carbon is in the form of spheres or fibers.
Claim 6
Dependent Claim
32 words
The polypropylene of claim 1 wherein the polypropylene is present in an amount of about 75 to 77% and the conductive carbon is present in an amount of about 23 to 25%.
Claim 7
Dependent Claim
9 words
The polypropylene of claim 5 comprising a nucleating agent.
Claim 8
Dependent Claim
38 words
A conductive polypropylene as set forth in claim 1, wherein said melt processing is carried out by forming a mixture of the polypropylene, the free-radical generator, and the carbon black and then introducing the mixture into a compounder.
Claim 9
Dependent Claim
33 words
A conductive polypropylene as set forth in claim 1, wherein said melt processing is carried-out by mixing the polypropylene and the free-radical generator in a compounder until fluxed and thereafter adding carbon black.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-05-26 | 1995-11-25 | 1996-05-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-05-26 | 1999-11-25 | 2000-05-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-05-26 | 2003-11-25 | 2004-05-26 | $7700.00 | Window Closed / Lapsed |