Methods of manufacturing wire, multi-layer wire pre-products and wires
View Patent ↗Exemplary methods for manufacturing a wire and resultant wires are disclosed herein. The method includes extruding a receptor cross-linkable polymer that is substantially free of curing agent about a conductive core and extruding a donor polymer in association with a curing agent. The method includes disposing the donor polymer about the receptor polymer and conductive core to create a multi-layer wire pre-product. The method also includes heat curing a multi-layer wire pre-product to form a wire.
1. A method of manufacturing a wire, comprising:
extruding a cross-linkable receptor polymer, substantially free of curing agent, about a conductive core;
extruding a donor polymer, wherein the donor polymer comprises a curing agent;
disposing the extruded donor polymer about the receptor polymer, thereby forming a multi-layer wire pre-product, wherein the donor polymer has a melt temperature lower than a melt temperature of the receptor polymer; and
heat curing the multi-layer wire pre-product, wherein heat curing comprises:
subjecting the multi-layer pre-product to a heat curing station operating at a cure temperature from about 130° C. to about 200° C.; and
melting the donor polymer, such that the curing agent in the donor polymer migrates from the donor polymer to the receptor polymer;
wherein the thickness of the receptor polymer to the thickness of the donor polymer is about 1:1 to about 1:5.
2. The method of claim 1 , wherein extruding the receptor polymer comprises disposing the receptor polymer in direct contact with the conductive core.
3. The method of claim 1 , wherein the conductive core comprises a semi-conductive material.
4. The method of claim 1 , wherein the conductive core comprises at least one of solid or stranded copper, nickel silver, beryllium, phosphor bronze, nickel, copper-clad aluminum, copper-clad steel, aluminium and steel.
5. The method of claim 1 , wherein the donor polymer has a melt temperature lower than a melt temperature of the receptor polymer by at least about 5° C.
6. The method of claim 1 , wherein disposing the donor polymer about the receptor polymer comprises co-extruding the receptor polymer and the donor polymer.
7. The method of claim 1 , wherein disposing the donor polymer about the receptor polymer comprises serially extruding the receptor polymer and the donor polymer.
8. The method of claim 1 , wherein disposing the donor polymer about the receptor polymer comprises placing the donor polymer in direct contact with the receptor polymer.
9. The method of claim 1 , wherein the conductive core has a cross-sectional area of at least about 1.5 mm 2 and wherein heat curing comprises subjecting the multi-layer wire pre-product to a heightened temperature for time sufficient to form a wire including insulation capable of remaining intact following at least 1500 cycles of abrasion scrapes with a needle having a diameter of about 0.45±0.01 mm.
10. The method of claim 1 , wherein the conductive core has a cross-sectional area of not greater than 0.22 mm 2 and wherein heat curing comprises subjecting the multi-layer wire pre-product to a heightened temperature for time sufficient to form a wire including insulation capable of remaining intact following at least 150 cycles of abrasion scrapes with a needle having a diameter of about 0.45±0.01 mm.
11. The method of claim 10 , wherein the time sufficient is at least about 20 seconds.
12. The method of claim 1 , wherein the conductive core has a cross-sectional area of no more than about 0.22 mm 2 and wherein heat curing comprises subjecting the multi-layer wire pre-product to a heightened temperature for time sufficient to form a wire including insulation capable of remaining intact following an abrasion scrape with a 150 J garnet sandpaper having a length of about 200 mm that is exerted with an applied force of at least about 0.63 N.