Patent EP0231068A2 successfully refreshed from Google Patents.
EP0231068A2
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Conductive polymer composition
Assignee: Raychem Corp
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Filing: 1987-01-12
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Granted: —
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Expires: 2007-01-12
Abstract
Abstract Conductive polymer compositions comprising a matrix polymer and a conductive particulate filler dispersed in the matrix polymer. At least some of the filler particles comprise a polymer and a homogeneous filler, eg. carbon black, dispersed therein. Preferably the filler is highly cross-linked so that it has a hot modulus of at least 250 psi (l7.5 kg/cm²) and is then dispersed in a melt-shapeable polymer. In this way it is possible to make conductive polymer compositions of high resistivity, eg. at least l,000 ohm-cm, with a high degree of reproduceability. Alternatively, the matrix polymer has a hot modulus of at least 250 psi (l7.5 kg/cm²) and is sintered.
Inventors
- 👤 Nachum Rosenzweig
- 👤 Pradeep Barma
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 08:02
CPC Classifications
H; H01; H01B; H01B1/00; H01B1/20; H01B1/24; H01C; H01C7/00; H01C7/02; H01C7/027
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
55 words
A shaped article composed of an electrically conductive composition which comprises (a) a continuous matrix comprising a first organic polymer, and (b) a first particulate conductive filler which is distributed in the matrix and which comprises (i) a second organic polymer, and (ii) a second particulate conductive filler which is distributed in the second polymer;
Claim 2
Dependent Claim
55 words
A shaped article composed of an electrically conductive composition which comprises (a) a continuous matrix comprising a first organic polymer, and (b) a first particulate conductive filler which is distributed in the matrix and which comprises (i) a second organic polymer, and (ii) a second particulate conductive filler which is distributed in the second polymer;
Claim 3
Dependent Claim
44 words
at least one of the matrix and the first filler having a hot modulus of at least 250 psi (l7.5 kg/cm²), and the matrix being a sintered polymer matrix if the first filler has a hot modulus of less than 250 psi (l7.5 kg/cm²).
Claim 4
Dependent Claim
44 words
at least one of the matrix and the first filler having a hot modulus of at least 250 psi (l7.5 kg/cm²), and the matrix being a sintered polymer matrix if the first filler has a hot modulus of less than 250 psi (l7.5 kg/cm²).
Claim 5
Dependent Claim
47 words
An article according to claim l which has been shaped by extrusion, injection molding or blow-molding and in which the first filler has a hot modulus of at least 250 psi (l7.5 kg/cm²), preferably at least 350 psi (24.5 kg/cm²), particularly at least 450 psi (3l.5 kg/cm²).
Claim 6
Dependent Claim
28 words
An article according to claim 2 wherein the first filler has been cross-linked by irradiating to a dose of at least 40 Mrad, preferably at least 60 Mrad.
Claim 7
Dependent Claim
48 words
An article according to any one of the preceding claims wherein the first and second polymers are crystalline thermoplastic polymers which are compatible with each other, and the composition exhibits PTC behavior and has a resistivity at 23°C of at least l,000 ohm-cm, preferably l,000 to l00,000 ohm-cm.
Claim 8
Dependent Claim
28 words
An article according to claim 4 wherein each of the first and second polymers is an olefin polymer, preferably polyethylene, and the second particulate filler is carbon black.
Claim 9
Dependent Claim
25 words
An article according to any one of claims l to 3 wherein at least one of the first and second polymers is a cross-linked elastomer.
Claim 10
Dependent Claim
52 words
An article according to claim l wherein the matrix is composed of particles of ultra high molecular weight polyethylene which have been sintered together so that the particles have coalesced without completely losing their identity, and the first filler is present substantially only at or near the boundaries of the coalesced particles.
Claim 11
Dependent Claim
22 words
An article according to any of the preceding claims wherein the conductive composition comprises a third particulate conductive filler, preferably carbon black.
Claim 12
Dependent Claim
68 words
A process for the preparation of a shaped article as claimed in any of claims l to 8 which comprises (l) mixing together (a) the first organic polymer, and (b) the first particulate conductive filler at least one of the first and second organic polymers having a hot modulus of at least 250 psi (l7.5 kg/cm²) at the time of mixing; and (2) shaping the mixture from step(l).
Claim 13
Dependent Claim
62 words
l0. A process for the preparation of a particulate conductive filler suitable for use in the process of claim 9 which comprises (l) preparing an intimate mixture of (a) an organic polymer and (b) a homogeneous particulate conductive filler; (2) cross-linking the mixture so that it has a hot modulus of at least 250 psi (l7.5 kg/cm²); and (3) comminuting the mixture.
References Cited (Backward Citations)
No citation records indexed.
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