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Conductive polymer composition

Assignee: Tyco International Ltd Bermuda
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Filing: 1992-06-05
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Granted: 1995-01-03
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Expires: 2012-06-05
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Abstract

Abstract A conductive polymer composition which has low resistivity and good electrical stability. In one aspect the composition comprises a nonconductive filler which is a dehydrated metal oxide. In another aspect the composition comprises a conductive filler which is metal particles in which the bulk density is less than 0.15 times the true density. Compositions of the invention are particularly useful for circuit protection devices.

Inventors

  • 👤 Daniel Chandler
  • 👤 Nelson H. Thein
  • 👤 Edward F. Chu

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 12:17
CPC Classifications
H; H01; H01C; H01C7/00; H01C7/02; H01C7/027; C; C08; C08K; C08K7/00; C08K7/02; C08K7/04; C08K7/06; H01B; H01B1/00; H01B1/20; H01B1/22

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 135 words
A conductive polymer composition which comprises (1) 40 to 70% by volume crystalline organic polymer which comprises a polyolefin, a copolymer of at least one olefin and at least one monomer copolymerisable therewith, or a fluoropolymer; (2) 25 to 40% by volume conductive particulate filler which is dispersed in the organic polymer and which comprises particles which (a) comprise nickel, (b) have a shape such that particles having the same shape and consisting of the same metal have a bulk density DB as measured by ASTM B329 which is (i) less than 1.3 g/cm 3 and (ii) q times the true density DT of the metal, where q is less than 0.15, (c) have a filamentary structure; and (3) a nonconductive filler which is obtained substantially complete dehydration of a hydrate of a metal oxide.
Claim 2
Dependent Claim 135 words
A conductive polymer composition which comprises (1) 40 to 70% by volume crystalline organic polymer which comprises a polyolefin, a copolymer of at least one olefin and at least one monomer copolymerisable therewith, or a fluoropolymer; (2) 25 to 40% by volume conductive particulate filler which is dispersed in the organic polymer and which comprises particles which (a) comprise nickel, (b) have a shape such that particles having the same shape and consisting of the same metal have a bulk density DB as measured by ASTM B329 which is (i) less than 1.3 g/cm 3 and (ii) q times the true density DT of the metal, where q is less than 0.15, (c) have a filamentary structure; and (3) a nonconductive filler which is obtained substantially complete dehydration of a hydrate of a metal oxide.
Claim 3
Dependent Claim 18 words
A composition according to claim 1 wherein the nonconductive filler is present at up to 20% by volume.
Claim 4
Dependent Claim 13 words
A composition according to claim 2 wherein the nonconductive filler comprises alumina trihydrate.
Claim 5
Dependent Claim 12 words
A composition according to claim 2 wherein the nonconductive filler comprises X-alumina.
Claim 6
Dependent Claim 19 words
A composition according to claim 1 wherein the conductive particles have a particle size of at least 1.0 μgm.
Claim 7
Dependent Claim 21 words
A composition according to claim 1 wherein the conductive particles have a bulk density of less than 1.0 g/cm 3 .
Claim 8
Dependent Claim 13 words
A composition according to claim 1 wherein the crystalline organic polymer comprises polyethylene.
Claim 9
Dependent Claim 20 words
A composition according to claim 1 wherein the conductive particles have an average particle size of 0.5 to 20 microns.
Claim 10
Dependent Claim 17 words
composition according to claim 2 wherein the nonconductive filler is present at 5 to 15% by volume.
Claim 11
Dependent Claim 10 words
A composition according to claim 1 which exhibits PTC behavior.
Claim 12
Dependent Claim 15 words
A composition according to claim 1 which has a resistivity of less than 1 ohm-cm.
Claim 13
Dependent Claim 68 words
A PTC conductive polymer composition which consists essentially of (1) 40 to 75% by volume crystalline organic polymer, which comprises a polyolefin, a copolymer of at least one olefin and at least one monomer copolymerisable therewith, or a fluoropolymer; (2) 25 to 40% by volume nickel particles which have a filamentary structure, (3) 1 to 20% by volume X-alumina, and (4) 0 to 5% by volume coupling agent.
Claim 14
Dependent Claim 68 words
A PTC conductive polymer composition which consists essentially of (1) 40 to 75% by volume crystalline organic polymer, which comprises a polyolefin, a copolymer of at least one olefin and at least one monomer copolymerisable therewith, or a fluoropolymer; (2) 25 to 40% by volume nickel particles which have a filamentary structure, (3) 1 to 20% by volume X-alumina, and (4) 0 to 5% by volume coupling agent.
Claim 15
Dependent Claim 20 words
A composition according to claim 12 wherein the nickel has a bulk density of less than 1.0 g/cm 3 .
Claim 16
Dependent Claim 15 words
A composition according to claim 12 wherein the coupling agent comprises a zirconate coupling agent.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1998-01-02 1998-07-04 1999-01-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-01-02 2002-07-04 2003-01-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-01-02 2006-07-04 2007-01-03 $7700.00 Window Closed / Lapsed

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