Non-lead jacket for non-metallic sheathed electrical cable
View Patent ↗A non metallic (NM) jacket has from about 40% to about 50% by weight of a polyvinyl chloride resin; from about 20% to about 35% by weight of a filler; from about 0.1% to about 0.5% by weight of an unsaturated primary amide derived from erucic acid; from about 20% to about 30% by weight of a phthalate-based plasticizer; and from about 0.5% to about 5% by weight of a lead-free heat-stabilizing system; wherein 100% is the weight of the jacket. Methods for improving the slip characteristics of a lead-free NM jacket for an electrical conductor are also provided.
1. A jacket for non-metallic sheathed electrical cable comprising:
from about 40% to about 50% by weight of a polyvinyl chloride resin;
from about 20% to about 35% by weight of a filler;
from about 0.1% to about 0.5% by weight of an unsaturated primary amide derived from erucic acid;
from about 20% to about 30% by weight of a phthalate-based plasticizer; and
from about 0.5% to about 5% by weight of a lead-free heat-stabilizing system, wherein 100% is the weight of the jacket.
2. The jacket of claim 1 wherein the polyvinyl chloride resin is present from about 43% to about 47% by weight.
3. The jacket of claim 1 wherein the polyvinyl chloride resin is produced with an anti-static compound.
4. The jacket of claim 3 wherein the anti-static compound is calcium stearate.
5. The jacket of claim 1 where the polyvinyl chloride resin has an inherent viscosity (IV) of less than 1.00.
6. The jacket of claim 1 wherein the filler comprises a metal carbonate.
7. The jacket of claim 1 wherein the filler comprises calcium carbonate.
8. The jacket of claim 7 wherein the calcium carbonate is present from about 25% to about 30% by weight.
9. The jacket of claim 1 wherein the unsaturated primary amide derived from erucic acid is present from about 0.1% to about 0.3% by weight.
10. The jacket of claim 1 wherein the phthalate-based plasticizer is selected from the group consisting of diisodecyl phthalate and a diisodecyl phthalate/extender oil blend.
11. The jacket of claim 10 wherein diisodecyl phthalate is present from about 21% to about 27% by weight.
12. The jacket of claim 1 wherein the heat stabilizing system is selected from the group consisting of tin-based stabilizers, mixed metal packages, metal-free stabilizers and mixtures thereof.
13. The jacket of claim 1 wherein the heat stabilizing system comprises a mixture of calcium-containing compounds and zinc-containing compounds.
14. The jacket of claim 1 wherein the heat stabilizing system comprises from about 1% to about 2% by weight.
15. A jacket for non-metallic (NM) sheathed electrical cable comprising:
from about 43% to about 47% by weight of a polyvinyl chloride resin package including calcium stearate;
from about 25% to about 30% by weight of filter;
from about 0.1% to 0.3% by weight of an unsaturated primary amide derived from erucic acid;
from about 21% to about 27% by weight of diisodecyl phthalate; and
from about 1% to about 2% by weight of a lead-free heat-stabilizing system, wherein 100% is the weight of the jacket.
16. A method of improving the slip characteristics of a jacket for non-metallic (NM) sheathed electrical cable, the method comprising: providing an easy-to-process chemical formulation comprising from about 40% to about 50% by weight of a polyvinyl chloride resin; from about 20% to about 35% by weight of a filler; from about 20% to about 30% by weight of a phthalate-based plasticizer, and from about 0.5% to about 5% by weight of a heat-stabilizing system; and adding a wax to the formulation, the wax comprising from about 0.1 to 0.5% by weight of an unsaturated primary amide derived from erucic acid, wherein 100% is the weight of the jacket layer composition with the wax added.
17. The method of claim 16 wherein the phthalate based plasticizer is diisodecyl phthalate.
18. The method of claim 16 wherein the unsaturated primary amide derived from erucic acid is present from about 0.1% to about 0.3% by weight.
19. The method of claim 16 wherein the heat-stabilizing system is group consisting of tin-based stabilizers, mixed metal packages, metal-free stabilizers and mixtures thereof.
20. The method of claim 19 wherein the heat stabilizing system comprises a mixture of calcium-containing compounds and zinc-containing compounds.
21. The method of claim 16 wherein the addition of the wax reduces pull force required to pull the cable by from about 52% to about 58%.
22. An extrudable chemical formulation for a jacket for non-metallic sheathed electrical cable comprising:
from about 40% to about 50% by weight of a polyvinyl chloride resin;
from about 20% to about 35% by weight of a filler;
from about 0.1% to about 0.5% by weight of an unsaturated primary amide derived from erucic acid;
from about 20% to about 30% by weight of a phthalate-based plasticizer; and
from about 0.5% to about 5% by weight of a lead-free heat-stabilizing system, wherein 100% is the weight of the jacket.
23. The extrudable chemical formulation of claim 22 wherein screen pack changes during extrusion are required about every 96 hours to about every 144 hours.