Claims
- 1. A copper conductor coated with an insulating layer of a flame retardant composition comprising:
- (a) a polymer selected from the group consisting of copolymers of ethylene and vinyl esters of C.sub.2-6 aliphatic carboxylic acids, copolymers of ethylene and C.sub.1-6 alkyl acrylates, copolymers of ethylene and C.sub.1-6 alkyl methacrylates, or mixtures thereof;
- (b) 80 to 400 phr hydrated inorganic filler;
- (c) 0.5 to 5 phr alkoxysilane;
- (d) 1 to 8 phr chemical crosslinking agent;
- (e) 0.25 to 8 phr processing additive; and
- (f) 1 to 8 phr antioxidant consisting of a combination of (1) a pentaerythritol betaalkylthiopropionate of the formula: ##STR6## wherein R.sub.1, R.sub.2, R.sub.3, and R.sub.4 are alkyl groups having from 8 to 22 carbon atoms and (2) a hindered phenol containing one or more groups of the formula ##STR7## where R is an alkyl group containing from 1 to 4 carbon atoms, with the weight ratio of (1) to (2) ranging from about 5:1 to 1:1.
- 2. The copper conductor of claim 1 wherein the hindered phenol is selected from the group consisting of 4,4'-methylenebis(2,6-di-t-butylphenol); tetrakis[methylene (3,5-di-t-butyl-4-hydroxyhydrocinnamate)]methane; 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)-benzene; 1,3,5-tris(3,5-di-t-butyl-4-hydroxybenzyl)-s-triazine 2,4,6(1H,3H,5H)trione; N,N'-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propanyl]hydrazine; and octadecyl 3,5-di-t-butyl-4-hydroxyhydrocinnamate.
- 3. The copper conductor of claim 2 wherein (a) is an ethylene-vinyl acetate copolymer containing from 9% to 30% vinyl acetate and having a melt index from 0.5 to 5, an ethylene-butyl acrylate copolymer containing 10% to 45% butyl acrylate and having a melt index of 0.1 to 3, or mixtures thereof; (b) is hydrated alumina; (c) is a vinylalkoxysilane; (d) is an organic peroxide; and (e) is a fatty acid, a fatty acid derivative, a polymeric resin, a hydrocarbon oil or mixture thereof.
- 4. The copper conductor of claim 3 wherein (c) is vinyltrimethoxysilane.
- 5. The copper conductor of claim 3 wherein (d) is dicumyl peroxide or alpha, alpha'-bis(t-butylperoxy)diisopropylbenzene.
- 6. The copper conductor of claim 3 wherein (e) is a mixture of a fatty acid and fatty acid amide present at a weight ratio from 2:1 to 1:10.
- 7. The copper conductor of claim 3 containing 80 to 200 phr (b); 0.75 to 4 phr (c); 1.5 to 5 phr (d); 1 to 6 phr (e); and 1 to 6 phr (f).
- 8. The copper conductor of claim 7 wherein (e) is a mixture of lauric acid and ethylene-bis-stearamide.
- 9. The copper conductor of claim 7 wherein (1) is pentaerythritol tetrakis(betalaurylthiopropionate) and (2) is octadecyl 3,5-di-t-butyl-4-hydroxyhydrocinnamate.
- 10. The copper conductor of claim 9 which is steam vulcanized.
- 11. The copper conductor of claim 7 wherein (1) is pentaerythritol tetrakis(betalaurylthiopropionate) and (2) is tetrakis[methylene (3,5-di-t-butyl-4-hydroxyhydrocinnate)]methane.
- 12. The copper conductor of claim 11 which is steam vulcanized.
CROSS-REFERENCE TO RELATED APPLICATIONS
This is a division of application Ser. No. 07/721,041, filed Jun. 26, 1991.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
4381362 |
Biggs |
Aug 1981 |
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Divisions (1)
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Number |
Date |
Country |
Parent |
721041 |
Jun 1991 |
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