CA1176453A - Conductive polymer compositions having improved properties under electrical stress - Google Patents
Conductive polymer compositions having improved properties under electrical stressInfo
- Publication number
- CA1176453A CA1176453A CA000375879A CA375879A CA1176453A CA 1176453 A CA1176453 A CA 1176453A CA 000375879 A CA000375879 A CA 000375879A CA 375879 A CA375879 A CA 375879A CA 1176453 A CA1176453 A CA 1176453A
- Authority
- CA
- Canada
- Prior art keywords
- composition
- volume
- carbon black
- ptc
- polymer component
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
- H01B1/20—Conductive material dispersed in non-conductive organic material
- H01B1/24—Conductive material dispersed in non-conductive organic material the conductive material comprising carbon-silicon compounds, carbon or silicon
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01C—RESISTORS
- H01C7/00—Non-adjustable resistors formed as one or more layers or coatings; Non-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material
- H01C7/02—Non-adjustable resistors formed as one or more layers or coatings; Non-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material having positive temperature coefficient
- H01C7/027—Non-adjustable resistors formed as one or more layers or coatings; Non-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material having positive temperature coefficient consisting of conducting or semi-conducting material dispersed in a non-conductive organic material
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Dispersion Chemistry (AREA)
- Physics & Mathematics (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Ceramic Engineering (AREA)
- Electromagnetism (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Thermistors And Varistors (AREA)
- Conductive Materials (AREA)
Abstract
ABRIDGEMENT
The invention relates to conductive polymer compositions comprising carbon black or graphite dispersed in a polymer. The compositions of the invention further comprise an arc-controlling additive such as alumina trihydrate. Such compositions have improved performance when subjected to electrical stress and are, therefore, particularly useful in circuit protection devices.
The invention relates to conductive polymer compositions comprising carbon black or graphite dispersed in a polymer. The compositions of the invention further comprise an arc-controlling additive such as alumina trihydrate. Such compositions have improved performance when subjected to electrical stress and are, therefore, particularly useful in circuit protection devices.
Description
i3 This invention relates to conductive polymer compositions and devices containing them, especially circuit protection devices.
Conductive and semi-conductive compositions comprising carbon black dispersed in a polymer are known. They may have room temperature resistivities ranging from less than 1 ohm.cm to 108 ohm.cm or more, and may exhibit positive temperature coefficient (PTC) behavior, zero temperature coefficient (ZTC or constant wattage) behavior or negative temperature coefficient (NTC) behavior.
Reference may be made, for example, to United States Patent Nos. 2,978,665, 3,243,753, 3,351,882, 3,823,217, 3,861,029, 3,950,604, 4,017,715, 4,177,376 and 4,246,468, to German OLS Nos. 2,413,475, 2,746,602, 2,755,076 and 2,821,570 to J. Applied Polymer Science 19, 813-815 (1975), Klason and KubatJ and to Polymer Engineering and Science 18 649-653 (1978), Narkis et al. Recent advances in this field are described in German OLS Nos. 2,948,350, 2,948,281, 2,949,173 and 3,002,721, in the applications corresponding to Canadian Serial Nos. 352,414 (MP0295), 352,413 (MP0295), 358,374 (MP0299) and 363,205 (MP0701), and in the applications filed contemporaneously with this application corresponding to Canadian Serial Nos. 375,886 (MP0712), 375,795 (MP0713), 375,856 (MP0714) and 375,877 (MP0720), and United States Patent Nos. 4,352,083 (MP0724) and 4,317,027 (MP0725).
,~; ~ - 3 -~ 7~3 Mp0715 In recent research into the use of circuit protection devices containing PTC conductive polymer elements, it was observed that previously proposed devices failed to give repeated and effective protection against fault conditions in which the device was subjected to a combination of high current and high voltage. We have found that the performance, under conditions of high electrical stress, of conductive polymer compositions containing carbon black or graphite as the sole conductive filler, can be markedly improved by adding tn such compo-sitions one or more of the additives which have previously been used to improve the tracking resistance of polymeric insulating compositions. Although it is not entirely clear precisely why such additives have this vaLuable effect, they are referred to herein as arc-controlling additives. It is thought that their efficacy is probably due, at least in part, to their ability to extinguish arcs after they have been formed, but the additives may also act to reduce the susceptibility of the composition to form arcs in the first place. In any event~ it is to be noted that the prior use of these additives, which has been to extinguish arcs on the contaminated surface of an electrical insulator, involves a very different situation ~t7~s~
from the present one, where the additives are effective in controlling arcs within a mass of conductive polymer (as well as at the surface thereof).
In one aspect, the invention provides an electrical device which comprises (a) a PTC element composed of a conductive polymer composition which exhibits PTC
behavior, which has a resistivity at 23C of less than 106ohm. cm, and which comprises:
(1) 20 to 91% by volume of an organic polymer component;
Conductive and semi-conductive compositions comprising carbon black dispersed in a polymer are known. They may have room temperature resistivities ranging from less than 1 ohm.cm to 108 ohm.cm or more, and may exhibit positive temperature coefficient (PTC) behavior, zero temperature coefficient (ZTC or constant wattage) behavior or negative temperature coefficient (NTC) behavior.
Reference may be made, for example, to United States Patent Nos. 2,978,665, 3,243,753, 3,351,882, 3,823,217, 3,861,029, 3,950,604, 4,017,715, 4,177,376 and 4,246,468, to German OLS Nos. 2,413,475, 2,746,602, 2,755,076 and 2,821,570 to J. Applied Polymer Science 19, 813-815 (1975), Klason and KubatJ and to Polymer Engineering and Science 18 649-653 (1978), Narkis et al. Recent advances in this field are described in German OLS Nos. 2,948,350, 2,948,281, 2,949,173 and 3,002,721, in the applications corresponding to Canadian Serial Nos. 352,414 (MP0295), 352,413 (MP0295), 358,374 (MP0299) and 363,205 (MP0701), and in the applications filed contemporaneously with this application corresponding to Canadian Serial Nos. 375,886 (MP0712), 375,795 (MP0713), 375,856 (MP0714) and 375,877 (MP0720), and United States Patent Nos. 4,352,083 (MP0724) and 4,317,027 (MP0725).
,~; ~ - 3 -~ 7~3 Mp0715 In recent research into the use of circuit protection devices containing PTC conductive polymer elements, it was observed that previously proposed devices failed to give repeated and effective protection against fault conditions in which the device was subjected to a combination of high current and high voltage. We have found that the performance, under conditions of high electrical stress, of conductive polymer compositions containing carbon black or graphite as the sole conductive filler, can be markedly improved by adding tn such compo-sitions one or more of the additives which have previously been used to improve the tracking resistance of polymeric insulating compositions. Although it is not entirely clear precisely why such additives have this vaLuable effect, they are referred to herein as arc-controlling additives. It is thought that their efficacy is probably due, at least in part, to their ability to extinguish arcs after they have been formed, but the additives may also act to reduce the susceptibility of the composition to form arcs in the first place. In any event~ it is to be noted that the prior use of these additives, which has been to extinguish arcs on the contaminated surface of an electrical insulator, involves a very different situation ~t7~s~
from the present one, where the additives are effective in controlling arcs within a mass of conductive polymer (as well as at the surface thereof).
In one aspect, the invention provides an electrical device which comprises (a) a PTC element composed of a conductive polymer composition which exhibits PTC
behavior, which has a resistivity at 23C of less than 106ohm. cm, and which comprises:
(1) 20 to 91% by volume of an organic polymer component;
(2) 4 to 65% by volume of a conductive filler component which is dispersed in said polymer component and which consists essentially of carbon black and/or graphite; and
(3) an arc-controlling additive which is a hydrated inorganic particulate material and which is dispersed in the polymer component; and (b) at least two electrodes which can be connected to a source of electrical power and which when so connected cause current to flow through the PTC element.
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~P07~5 The PTC compositions defined above are particularly useful in circuit protection devices as described in the comtemporaneously filed applications corresponding to Canadian Serial No. 375,795, and United States Patent Nos. 4,352,083 and 4,317,027 (MP0713, MP0724 and ~pO725).
The compositions can be any of the PTC compositions disclosed in the prior art and the earlier applications referred to above modified by the inclusion of at least one arc-controlling additive as defined. The invention is especially valuable in relation to circuit protection devices which usually have a resistance below 50 ohms, preferably 0.1 to 25 ohms, at 23C as described in copending Canadian Patent Application No. 375,795, and in which the PTC composition has low resistivity at 23C, e~g. below 20 ohm. cm, preferably below 10 ohm.
cm, especially below 2 ohm. cm.
The preferred arc-controlling additive for use in the present invention is alumina trihydrate, A12033H20.
Another additive that can be used is magnesia hydrate.
~ 76453 MP0715 The conductive filler and the arc-controlling additive preferably have a total surface area of at least 1,800, especially at least 3,000, particularly at least 4,000, m /100 cc of composition, with higher values, eg. at least 8,000 m2/100 cc, at leas-t 10,0~0 m2/100 cc and at least 12,000 m2/100 cc being particularly preferred.
The composition should contain an effective amount of the arc-controlling additive, typically 5 ~o 65%, preferably 10 to 35~, by volume of the composition.
The composition can also contain further additives which are known to enhance the effectiveness of anti-tracking additives in insulating compositions.
Examples of such additives include the phosphorus-containiny compounds disclosed in British Patent No.1,575,465 and the oxides of elements of the transition series, lanthanide series or non-transuranic actinicle series disclosed in British Patents ~os. 1,337,951 and 1,337,952.
.~
~ 53 MP0715 The conductive filler in the composition prefer-ably consists essentially of at least one carbon black.
The carbon black is selected ~ith a view to the elec-trical characteristics desired in the composition, as taught by the various patents and applications referred to above. Thus for low resistivity PTC composltions, the carbon black preferably has a particle size, D, which is from 20 to 150 millimicrons and a surface area, S in m /g such that S/D is not more than 10.
~hen usin~ such a carbon black, preferably the quantity S (volume of conductive filler + volume of arc-controlling additive) D volume of p~lymer comp~nent is less than 1.
The polymer component in the composition, which 15 may comprise one or more polymers, preferably has a crystallinity of at least 1%, especially at least 5%, particularly at least 10~. Preferably the polymer component consists essentially of one or more crystal-line polymers selected from polyolefins and copolymers 20 of at least one olefin and at least one polar comonomer copolymerisable therewith, eg. polyethylene or poly-propylene. Other suitable polymers are referred to in the patents and applications referred to above.
~ 3 ~iP0715 The composition may be substantially free of cross-linking or may be cross-linked, eg. to a gel fraction of at least 0.4 or 0.6. For some purposes, compositions free of cross-linking are preferred, because the presence of cross-linking tends to increase the likelihood of formation of carbonaceous conductive paths when arcing takes place.
The composition can be prepared by dispersing the carbon black or graphite, the arc-controlling additive and any other additives in the polymer com-ponent in any suitable way. ~he composition can be shaped by molding or extrusion or another melt-shaping technique into an element of the desired shape, any cross-linking thereof being carried out after such shaping.
Conductive polymer compositions comprising a crystalline polymer component, at least 4~ by volume of carbon black and at least 4~ by volume of a non-conductive particulate filler, the total surface area of the carbon black and filler being at least 1800 m /100 cc of composition, are described and claimed in the comptemporaneously filed application corresponding to Canadian Serial Nos. 375,886 and 375,856 (~P0712 and MP0714).
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The invention is illustratad by the ~ollowing Examples.
Example 1 The ingredients and amo~nts thereof given in the Table 1 below were used in this Example.
g wt~, v o l O 9 w t ,o vol~
Carbon ~lack 144446.9 32.2 1143.933.826.9 ¦Furnex N765)*
Polyethylene 157251.1 65.4 1246.336.854.7 (Marlex 60û:3)*
Filler - - - 94828.016.5 (Hydral 705)*
Antioxidant 622.0 2.3 48.81.41.9 ..
NOTES: -Furnex N765*(available from City Services Co) has a particle `
size (D) of 60 millimicr~ns, a density of 1.8 g/cc, and a surface area (s) of 32 m /9.
Marlex 6003*is a high density polyethylene with a rrlelt index of 0.3 whic17 iS available from PhiLlips Petroleum Co.
The antioxidant used was an oLigomer of 4,4-thio bis (3-methyl-6-t-butyl phenol) with an average degree of polymerization of 3-4, as described in U.S. Patent No. 3,986,981.
Hydral 705*is alurnina trihydrate.
*Tracle Mark 6~53 The ingredients for the master batch were dry blended and then mixed for 8 minutes in a Banbury* mixer turning at high gear. The mixture was dumped, cooled and granulated. The final mix was prepared by dry blending 948 g of the hydral 705* with 2439 g. o~ the master batch mixture, and then mixing the dry blend for 4-5 minutes in a Banbury* mixer turning at high gear. The mixture was dumped, cooled, granulated and dried ~at 70C. 1 Torr for 16 hours).
The granulated final mix was melt extruded in the form of a strip about 1.27 cm wide and about 0.27 cm thick, using a cross-head die, around a pair of pre-heated 20 AWG (diameter 0.095 cm) l9/32 stranded nickel-plated copper wires whose centers were 0.6 cm apart. The extruded product was cut into 2.5 cm lengths, and the polymeric composition removed from half of each length to produce a circuit control device as shown in Figure 4 of the contemporaneously filed application corresponding to United States Patent No. 4,352,083 (MP0724).
Examples 2-4 The ingreidents used in these Examples and the amounts thereof are shown in Table 2 below. The antioxidant is as specified in Table 1. Sterling NS*
and Sterling *Trade Mark ~L~'7~i3 SO* are available from Cabot, Hydral 705* from Alcan, Maglite D* from Merck, and Kadox 15* from Gulf and Western, and they have the following properties Material Particle Size DensitySurface Area millimicrons g/cc m2/g Sterling NS* Carbon black (N774~ 75 1.8 25 Sterling SO* Carbon black (N550~ 41 1.8 42 ~Iydral 705* A1203 3~l200.5-2,000 2.42 12 - 15 Maglite D* MgO ~44 3.32 Kadox 15* 130 5.52-6.52 8.5 In Example 2, the Master Batch ingredients were blended in a pre-heated Banbury* mixer, and the mixture dumped, cooled and granulated. 67 g. of the granulated mixture was banded on a 7.6 cm electric roll mill, and the Hydral* was added in portions to give a uniform mixture;
mixing was continued for several more minutes and the mixture was then removed from the mill, cooled, granulated and compression-molded into slabs.
In Example 3, the Master Batch ingredients were blended in a pre-heated Banbury* mixer, and the mixture dumped, cooled and granulated. 67 g. of the granulated mixture was b.lllded on a 3 inch electric roll mlll, and the ~Iydral* was added ln portions to glvc a unlform mixture;
mixing was continued Eor several more minutes and the *Trade Ma-rk , ~'76453 mixture was then removed from the mill, cooled, granulated and co~pression-molded into slabs.
In Example 4 the procedure described For Example 2 was followed, using the different ingredients shown in Table 2, except that 50 9. of the granulated Master Batch was used and 50 g. of the filler (Maglite D)*added to it.
*Trade Mark ~:
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~P07~5 The PTC compositions defined above are particularly useful in circuit protection devices as described in the comtemporaneously filed applications corresponding to Canadian Serial No. 375,795, and United States Patent Nos. 4,352,083 and 4,317,027 (MP0713, MP0724 and ~pO725).
The compositions can be any of the PTC compositions disclosed in the prior art and the earlier applications referred to above modified by the inclusion of at least one arc-controlling additive as defined. The invention is especially valuable in relation to circuit protection devices which usually have a resistance below 50 ohms, preferably 0.1 to 25 ohms, at 23C as described in copending Canadian Patent Application No. 375,795, and in which the PTC composition has low resistivity at 23C, e~g. below 20 ohm. cm, preferably below 10 ohm.
cm, especially below 2 ohm. cm.
The preferred arc-controlling additive for use in the present invention is alumina trihydrate, A12033H20.
Another additive that can be used is magnesia hydrate.
~ 76453 MP0715 The conductive filler and the arc-controlling additive preferably have a total surface area of at least 1,800, especially at least 3,000, particularly at least 4,000, m /100 cc of composition, with higher values, eg. at least 8,000 m2/100 cc, at leas-t 10,0~0 m2/100 cc and at least 12,000 m2/100 cc being particularly preferred.
The composition should contain an effective amount of the arc-controlling additive, typically 5 ~o 65%, preferably 10 to 35~, by volume of the composition.
The composition can also contain further additives which are known to enhance the effectiveness of anti-tracking additives in insulating compositions.
Examples of such additives include the phosphorus-containiny compounds disclosed in British Patent No.1,575,465 and the oxides of elements of the transition series, lanthanide series or non-transuranic actinicle series disclosed in British Patents ~os. 1,337,951 and 1,337,952.
.~
~ 53 MP0715 The conductive filler in the composition prefer-ably consists essentially of at least one carbon black.
The carbon black is selected ~ith a view to the elec-trical characteristics desired in the composition, as taught by the various patents and applications referred to above. Thus for low resistivity PTC composltions, the carbon black preferably has a particle size, D, which is from 20 to 150 millimicrons and a surface area, S in m /g such that S/D is not more than 10.
~hen usin~ such a carbon black, preferably the quantity S (volume of conductive filler + volume of arc-controlling additive) D volume of p~lymer comp~nent is less than 1.
The polymer component in the composition, which 15 may comprise one or more polymers, preferably has a crystallinity of at least 1%, especially at least 5%, particularly at least 10~. Preferably the polymer component consists essentially of one or more crystal-line polymers selected from polyolefins and copolymers 20 of at least one olefin and at least one polar comonomer copolymerisable therewith, eg. polyethylene or poly-propylene. Other suitable polymers are referred to in the patents and applications referred to above.
~ 3 ~iP0715 The composition may be substantially free of cross-linking or may be cross-linked, eg. to a gel fraction of at least 0.4 or 0.6. For some purposes, compositions free of cross-linking are preferred, because the presence of cross-linking tends to increase the likelihood of formation of carbonaceous conductive paths when arcing takes place.
The composition can be prepared by dispersing the carbon black or graphite, the arc-controlling additive and any other additives in the polymer com-ponent in any suitable way. ~he composition can be shaped by molding or extrusion or another melt-shaping technique into an element of the desired shape, any cross-linking thereof being carried out after such shaping.
Conductive polymer compositions comprising a crystalline polymer component, at least 4~ by volume of carbon black and at least 4~ by volume of a non-conductive particulate filler, the total surface area of the carbon black and filler being at least 1800 m /100 cc of composition, are described and claimed in the comptemporaneously filed application corresponding to Canadian Serial Nos. 375,886 and 375,856 (~P0712 and MP0714).
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The invention is illustratad by the ~ollowing Examples.
Example 1 The ingredients and amo~nts thereof given in the Table 1 below were used in this Example.
g wt~, v o l O 9 w t ,o vol~
Carbon ~lack 144446.9 32.2 1143.933.826.9 ¦Furnex N765)*
Polyethylene 157251.1 65.4 1246.336.854.7 (Marlex 60û:3)*
Filler - - - 94828.016.5 (Hydral 705)*
Antioxidant 622.0 2.3 48.81.41.9 ..
NOTES: -Furnex N765*(available from City Services Co) has a particle `
size (D) of 60 millimicr~ns, a density of 1.8 g/cc, and a surface area (s) of 32 m /9.
Marlex 6003*is a high density polyethylene with a rrlelt index of 0.3 whic17 iS available from PhiLlips Petroleum Co.
The antioxidant used was an oLigomer of 4,4-thio bis (3-methyl-6-t-butyl phenol) with an average degree of polymerization of 3-4, as described in U.S. Patent No. 3,986,981.
Hydral 705*is alurnina trihydrate.
*Tracle Mark 6~53 The ingredients for the master batch were dry blended and then mixed for 8 minutes in a Banbury* mixer turning at high gear. The mixture was dumped, cooled and granulated. The final mix was prepared by dry blending 948 g of the hydral 705* with 2439 g. o~ the master batch mixture, and then mixing the dry blend for 4-5 minutes in a Banbury* mixer turning at high gear. The mixture was dumped, cooled, granulated and dried ~at 70C. 1 Torr for 16 hours).
The granulated final mix was melt extruded in the form of a strip about 1.27 cm wide and about 0.27 cm thick, using a cross-head die, around a pair of pre-heated 20 AWG (diameter 0.095 cm) l9/32 stranded nickel-plated copper wires whose centers were 0.6 cm apart. The extruded product was cut into 2.5 cm lengths, and the polymeric composition removed from half of each length to produce a circuit control device as shown in Figure 4 of the contemporaneously filed application corresponding to United States Patent No. 4,352,083 (MP0724).
Examples 2-4 The ingreidents used in these Examples and the amounts thereof are shown in Table 2 below. The antioxidant is as specified in Table 1. Sterling NS*
and Sterling *Trade Mark ~L~'7~i3 SO* are available from Cabot, Hydral 705* from Alcan, Maglite D* from Merck, and Kadox 15* from Gulf and Western, and they have the following properties Material Particle Size DensitySurface Area millimicrons g/cc m2/g Sterling NS* Carbon black (N774~ 75 1.8 25 Sterling SO* Carbon black (N550~ 41 1.8 42 ~Iydral 705* A1203 3~l200.5-2,000 2.42 12 - 15 Maglite D* MgO ~44 3.32 Kadox 15* 130 5.52-6.52 8.5 In Example 2, the Master Batch ingredients were blended in a pre-heated Banbury* mixer, and the mixture dumped, cooled and granulated. 67 g. of the granulated mixture was banded on a 7.6 cm electric roll mill, and the Hydral* was added in portions to give a uniform mixture;
mixing was continued for several more minutes and the mixture was then removed from the mill, cooled, granulated and compression-molded into slabs.
In Example 3, the Master Batch ingredients were blended in a pre-heated Banbury* mixer, and the mixture dumped, cooled and granulated. 67 g. of the granulated mixture was b.lllded on a 3 inch electric roll mlll, and the ~Iydral* was added ln portions to glvc a unlform mixture;
mixing was continued Eor several more minutes and the *Trade Ma-rk , ~'76453 mixture was then removed from the mill, cooled, granulated and co~pression-molded into slabs.
In Example 4 the procedure described For Example 2 was followed, using the different ingredients shown in Table 2, except that 50 9. of the granulated Master Batch was used and 50 g. of the filler (Maglite D)*added to it.
*Trade Mark ~:
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Claims (14)
1. An electrical device which comprises (a) a PTC element composed of a conductive polymer composition which exhibits PTC behaviour, which has a resistivity at 23°C of less than 106 ohm cm, and which comprises (1) 20 to 91% by volume of an organic polymer component;
(2) 4 to 65% by volume of a conductive filler component which is dispersed in said polymer component and which consists essentially of carbon black and/or graphite; and (3) an arc-controlling additive which is a hydrated inorganic particulate material and which is in the polymer component; and (b) at least two electrodes which can be connected to a source of electrical power and which when so connected cause current to flow through the PTC element
(2) 4 to 65% by volume of a conductive filler component which is dispersed in said polymer component and which consists essentially of carbon black and/or graphite; and (3) an arc-controlling additive which is a hydrated inorganic particulate material and which is in the polymer component; and (b) at least two electrodes which can be connected to a source of electrical power and which when so connected cause current to flow through the PTC element
2. A device according to Claim 1 wherein the arc-controlling additive is a present in amount 5 to 65%
by volume of the composition.
by volume of the composition.
3. A device according to Claim 2 wherein the arc-controlling additive is present in amount 10 to 35% by volume of the composition.
. - 15 -
. - 15 -
4. A device according to Claim 1, wherein the particulate material is alumina trihydrate.
5. A device according to Claim 1, 2 or 4, wherein the conductive filler and the arc-controlling additive have a total surface area of at least 1,800 m2 per 100 cc. of composition.
6. A device according to Claim 1, 2 or 4, wherein the polymer component has at least 5% crystal-linity and the conductive filler component (a) comprises carbon black having a particle size, D, which is from 20 to 150 millimicrons and a surface area, S, in m2/g such that S/D is not more than 10, and (b) is present in amount such that the composition has a resistivity at 23°C of less than 20 ohm.cm.
7. A device according to Claim 1, 2 or 4, wherein the polymer component has at least 5% crystal-linity and the conductive filler component (a) comprises carbon black having a particle size, D, which is from 20 to 150 millimicrons and a surface area, S, in m2/g such that S/D is not more than 10, and (b) is present in amount such that the composition has a resistivity at 23°C of less than 20 ohm.cm. and wherein the quantity is less than 1.
8. A device according to Claim 1, 2 or 4, wherein at least one of the electrodes is in physical contact with the PTC element.
9. A device according to Claim 1, which is circuit protection device.
10. A device according to Claim 9, which has a resistance less than 50 ohms at 23°C.
11. A device according to Claim 10, which has a resistance of 0.1 to 25 ohms at 23°C.
12. A device according to Claim 9, wherein the PTC composition exhibits PTC behaviour and has a resitivity at 23°C below 10 ohm.cm.
13. A device according to Claim 9, wherein the PTC composition comprises (a) 20 to 91% by volume of a polymer component having at least 10% crystallinity;
(b) 4 to 65% by volume of carbon black; and (c) 5 to 65% by volume of alumina trihydrate the carbon black and the alumina trihydrate having a total surface area of at least 1,800 m2/100 cc of composition.
(b) 4 to 65% by volume of carbon black; and (c) 5 to 65% by volume of alumina trihydrate the carbon black and the alumina trihydrate having a total surface area of at least 1,800 m2/100 cc of composition.
14. A device according to Claim 13, wherein at least one of said electrodes is in direct physical contact with said PTC composition.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US14198980A | 1980-04-21 | 1980-04-21 | |
| US141,989 | 1980-04-21 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1176453A true CA1176453A (en) | 1984-10-23 |
Family
ID=22498109
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000375879A Expired CA1176453A (en) | 1980-04-21 | 1981-04-21 | Conductive polymer compositions having improved properties under electrical stress |
Country Status (7)
| Country | Link |
|---|---|
| EP (1) | EP0038713B1 (en) |
| JP (1) | JPS56161463A (en) |
| AT (1) | ATE29329T1 (en) |
| CA (1) | CA1176453A (en) |
| DE (1) | DE3176415D1 (en) |
| GB (1) | GB2074169B (en) |
| HK (1) | HK83089A (en) |
Families Citing this family (23)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4413301A (en) | 1980-04-21 | 1983-11-01 | Raychem Corporation | Circuit protection devices comprising PTC element |
| EP0099717A3 (en) * | 1982-07-20 | 1986-09-17 | The British Petroleum Company p.l.c. | Conducting unsaturated polyester resin compositions |
| EP0190772B1 (en) * | 1982-11-17 | 1991-05-08 | Kabushiki Kaisha Meidensha | Electrically conductive plastics material |
| ATE77155T1 (en) | 1983-06-30 | 1992-06-15 | Raychem Corp | METHOD OF DETECTING AND OBTAINING INFORMATION ABOUT THE CHANGES OF VARIABLES. |
| JPS6028195A (en) * | 1983-07-27 | 1985-02-13 | 松下電器産業株式会社 | Heater |
| JPS6053560A (en) * | 1983-09-05 | 1985-03-27 | Dainichi Seika Kogyo Kk | Conductive polyphenylene sulfide resin composition |
| US4528213A (en) * | 1983-11-22 | 1985-07-09 | Rca Corporation | EMI/RFI Shielding composition |
| US4774024A (en) * | 1985-03-14 | 1988-09-27 | Raychem Corporation | Conductive polymer compositions |
| US4884163A (en) * | 1985-03-14 | 1989-11-28 | Raychem Corporation | Conductive polymer devices |
| US4647896A (en) * | 1985-03-14 | 1987-03-03 | Raychem Corporation | Materials for packaging circuit protection devices |
| JPS62119272A (en) * | 1985-11-19 | 1987-05-30 | Mitsubishi Petrochem Co Ltd | Resin resistor |
| JPH0777161B2 (en) * | 1986-10-24 | 1995-08-16 | 日本メクトロン株式会社 | PTC composition, method for producing the same and PTC element |
| DE3722480A1 (en) * | 1987-07-08 | 1989-01-19 | Kabelmetal Electro Gmbh | CRAFT-RESISTANT INSULATING MOLDED PARTS |
| US4924074A (en) * | 1987-09-30 | 1990-05-08 | Raychem Corporation | Electrical device comprising conductive polymers |
| US5166658A (en) * | 1987-09-30 | 1992-11-24 | Raychem Corporation | Electrical device comprising conductive polymers |
| US4907340A (en) * | 1987-09-30 | 1990-03-13 | Raychem Corporation | Electrical device comprising conductive polymers |
| WO1990003681A1 (en) * | 1988-09-20 | 1990-04-05 | Raychem Limited | Circuit protection arrangement |
| US5122775A (en) * | 1990-02-14 | 1992-06-16 | Raychem Corporation | Connection device for resistive elements |
| US5174924A (en) * | 1990-06-04 | 1992-12-29 | Fujikura Ltd. | Ptc conductive polymer composition containing carbon black having large particle size and high dbp absorption |
| US5089801A (en) * | 1990-09-28 | 1992-02-18 | Raychem Corporation | Self-regulating ptc devices having shaped laminar conductive terminals |
| US6111234A (en) * | 1991-05-07 | 2000-08-29 | Batliwalla; Neville S. | Electrical device |
| EP1274100B1 (en) * | 2001-07-02 | 2011-02-02 | Dupont-Mitsui Fluorochemicals Company, Ltd. | Electrically conducting fluoropolymer composition |
| JP6729410B2 (en) * | 2017-01-17 | 2020-07-22 | トヨタ自動車株式会社 | All solid state battery |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR1207401A (en) * | 1955-07-21 | 1960-02-16 | Thomson Houston Comp Francaise | Insulation for electrical devices |
| US3351882A (en) * | 1964-10-09 | 1967-11-07 | Polyelectric Corp | Plastic resistance elements and methods for making same |
| GB1185473A (en) * | 1966-09-14 | 1970-03-25 | British Insulated Callenders | Improvements in Conductive or Semi-Conductive Fibrous Sheet Material. |
| JPS5136876A (en) * | 1974-09-25 | 1976-03-27 | Hitachi Ltd | Sairisuta no reetokokasokuteihoho narabini sochi |
| JPS5179140A (en) * | 1974-12-28 | 1976-07-09 | Furukawa Electric Co Ltd | HANDO DENSEIJUSHI SEIBUTSU |
| GB1604735A (en) * | 1978-04-14 | 1981-12-16 | Raychem Corp | Ptc compositions and devices comprising them |
| US4237441A (en) * | 1978-12-01 | 1980-12-02 | Raychem Corporation | Low resistivity PTC compositions |
-
1981
- 1981-04-21 JP JP6053681A patent/JPS56161463A/en active Granted
- 1981-04-21 CA CA000375879A patent/CA1176453A/en not_active Expired
- 1981-04-21 AT AT81301764T patent/ATE29329T1/en not_active IP Right Cessation
- 1981-04-21 EP EP81301764A patent/EP0038713B1/en not_active Expired
- 1981-04-21 DE DE8181301764T patent/DE3176415D1/en not_active Expired
- 1981-04-21 GB GB8112310A patent/GB2074169B/en not_active Expired
-
1989
- 1989-10-19 HK HK830/89A patent/HK83089A/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| JPS56161463A (en) | 1981-12-11 |
| EP0038713A2 (en) | 1981-10-28 |
| GB2074169A (en) | 1981-10-28 |
| HK83089A (en) | 1989-10-27 |
| DE3176415D1 (en) | 1987-10-08 |
| GB2074169B (en) | 1983-12-21 |
| EP0038713B1 (en) | 1987-09-02 |
| JPH0428744B2 (en) | 1992-05-15 |
| ATE29329T1 (en) | 1987-09-15 |
| EP0038713A3 (en) | 1981-11-18 |
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