Claims
- 1. An insulated electrical conductor which comprises
- (1) an elongated electrical conductor; and
- (2) electrical insulation which comprises
- (a) an inner electrically insulating layer which (i) is composed of a first melt-processed, cross-linked fluorocarbon polymer composition wherein the polymer has a melting point of at least 200.degree. C., and (ii) has a first M.sub.100 value of 0 to 350 psi and an elongation of at least 100%; and
- (b) an outer electrically insulating layer which (i) is separated from the conductor by the inner layer, (ii) is in contact with said inner layer; (iii) is composed of a second melt-processed cross-linked fluorocarbon polymeric composition wherein the polymer has a melting point of at least 300.degree. C., and (iv) has a second M.sub.100 value which is at least 350 psi and at least 50 psi higher than the first M.sub.100 value and an elongation of 40 to 150%.
- 2. An insulated conductor according to claim 1 wherein the polymer in at least one of the first and second polymeric compositions consists essentially of a crystalline fluorocarbon polymer.
- 3. An insulated conductor according to claim 2 wherein the polymer in each of the layers consists essentially of a copolymer of ethylene and tetrafluoroethylene.
- 4. An insulated conductor according to claim 3 wherein the copolymer consists essentially of 35 to 60 mole percent of units derived from ethylene, 35 to 60 mole percent of units derived from tetrafluoroethylene and 0 to 10 mole percent of units derived from at least one additional copolymerizable comonomer.
- 5. An insulated conductor according to claim 1 wherein the inner layer has an M.sub.100 value of 0 to 250 psi and the outer layer has an M.sub.100 value of at least 400 psi.
- 6. An insulated conductor according to claim 5 wherein the inner layer has an M.sub.100 value of 50 to 150 psi and the outer layer has an M.sub.100 value of at least 450 psi.
- 7. An insulated conductor according to claim 6 wherein the outer layer has an M.sub.100 value of at least 600 psi.
- 8. An insulated conductor according to claim 1 wherein the inner layer has an elongation of at least 150% and the outer layer has an elongation of 50 to 120%.
- 9. An insulated conductor according to claim 1 wherein the inner layer has an elongation at 200 to 300%.
- 10. Insulated electrical wire which comprises
- (1) a metal conductor; and
- (2) electrical insulation which surrounds the conductor and which comprises
- (a) an inner electrically insulating layer which
- (i) surrounds and is in direct physical contact with the conductor,
- (ii) is composed of a radiation cross-linked polymeric composition wherein the polymer consists essentially of a crystalline copolymer which has a melting point of at least 250.degree. C. and consists essentially of 35 to 60 mole percent of units derived from ethylene, 35 to 60 mole percent of units derived from tetrafluoroethylene and 0 to 10 mole percent of units derived from at least one additional copolymerizable comonomer;
- (iii) has an M.sub.100 value at 320.degree. C. of 0 to 350 psi;
- (iv) has an elongation of at least 125%; and
- (v) is 0.003 to 0.015 inch thick; and
- (b) an outer electrically insulating layer which
- (i) surrounds and is in direct physical contact with the inner layer,
- (ii) is composed of a radiation cross-linked polymeric composition wherein the polymer consists essentially of a crystalline copolymer which has a melting point of at least 250.degree. C. and consists essentially of 35 to 60 mole percent of units derived from ethylene, 35 to 60 mole percent of units derived from tetrafluoroethylene and 0 to 10 mole percent of units derived from at least one additional copolymerizable comonomer;
- (iii) has an M.sub.100 value at 320.degree. C. of at least 400 psi;
- (iv) has an elongation of 50 to 120%; and
- (v) is 0.004 to 0.025 inch thick.
- 11. Insulated electrical wire according to claim 10 wherein the inner layer has an elongation of 200 to 300% and the outer layer has an elongation of 50 to 120%.
- 12. Insulated electrical wire according to claim 10 wherein each layer has been cross-linked with the aid of at least one of triallyl cyanurate and triallyl isocyanurate.
Parent Case Info
This application is a continuation of copending application Ser. No. 786,806, filed Oct. 11, 1985, now abandoned.
US Referenced Citations (21)
Foreign Referenced Citations (2)
Number |
Date |
Country |
893080 |
Feb 1972 |
CAX |
1151255 |
Aug 1983 |
CAX |
Non-Patent Literature Citations (2)
Entry |
Military Specification Sheet MIL-W-22759/34B, Published Jul. 10, 1980. |
Report Number TR-2333, "Testing of Selected Aircraft Electrical Wire Insulations". |
Continuations (1)
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Number |
Date |
Country |
Parent |
786806 |
Oct 1985 |
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