Flame retardant thermoplastic elastomers

1. A thermoplastic elastomer compound, consisting of:

(a) from about 20 to about 35 weight percent of a polyphenylene ether, based on the total weight of the compound, wherein the polyphenylene ether is unblended or blended with an aromatic vinyl group thermoplastic resin;

(b) from about 20 to about 40 weight percent of a hydrogenated styrenic block copolymer, based on the total weight of the compound;

(c) from about 5 to about 30 weight percent of a combination of organo-phosphinate and melamine polyphosphate, based on the total weight of the compound;

(d) from about 5 to about 30 weight percent of a nucleated olefinic polymer, based on the total weight of the compound;

(e) from about 5 to about 30 weight percent of a plasticizing oil, based on the total weight of the compound;

(f) from about 5 to about 25 weight percent of a tackifier, based on the total weight of the compound; and

(g) optionally, from 0 to about 5 weight percent of at least one additive, based on the total weight of the compound, wherein the additive is selected from the group consisting of antioxidants; pigments, colorants or dyes; stabilizers; and ultraviolet light absorbers;

wherein the compound has a before-aging tensile elongation of >200% and an after-aging tensile elongation residual of at least 75%, according to Underwriters' Laboratory test UL 62; and

wherein the compound has a V-0 rating at 3 mm thickness, according to Underwriters' Laboratory test UL 94.

2. The compound of claim 1 , wherein the hydrogenated styrenic block copolymer has a weight average molecular weight of between about 70,000 and about 160,000 and a ratio of styrenic end-block to olefinic mid-block ranging from about 20/80 to about 40/60.

3. The compound of claim 1 , wherein the hydrogenated styrenic block copolymer is selected from the group consisting of styrene-ethylene butylene-styrene polymers, styrene-ethylene propylene-styrene polymers, hydrogenated styrene-isoprene block copolymers, and hydrogenated styrene-butadiene block copolymers, styrene-ethylene-ethylene-propylene-styrene copolymers, and combinations of them.

4. The compound of claim 1 , wherein the polyphenylene ether is selected from the group consisting of poly(2,6-dimethyl-1,4-phenylene ether), poly(2,6-diethyl-1,4-phenylene ether), poly(2-methyl-6-ethyl-1,4-phenylene ether), poly(2-methyl-6-propyl-1,4-phenylene ether), poly(2,6-dipropyl-1,4-phenylene ether), poly(2-ethyl-6-propyl-1,4-phenylene ether), poly(2,6-dimethoxy-1,4-phenylene ether), poly(2,6-di(chloro methyl)-1,4-phenylene ether), poly(2,6-di(bromo methyl)-1,4-phenylene ether), poly(2,6-diphenyl-1,4-phenylene ether), poly(2,6-ditoluyl-1,4-phenylene ether), poly(2,6-dichloro-1,4-phenylene ether), poly(2,6-dibenzyl-1,4-phenylene ether), poly(2,5-dimethyl-1,4-phenylene ether), and combinations thereof.

5. The compound of claim 4 , wherein the aromatic vinyl group thermoplastic resin is selected from the group consisting of homopolymers of styrene or its derivatives, copolymers of styrene and p-methyl styrene, copolymers of styrene and alpha-methyl styrene, copolymers of styrene and alpha-methyl-p-methyl styrene, copolymers of styrene and chlorostyrene, copolymers of styrene and bromostyrene, and combinations thereof.

6. The compound of claim 1 , wherein the nucleated olefinic polymer is nucleated polypropylene homopolymer.

7. The compound of claim 1 in the form of an insulation layer enveloping a protected electrical line or in the form of a jacketing layer enveloping a protected electrical line.

8. A plastic article made from a compound of claim 1 .

9. The plastic article of claim 8 , in the form of an electrical part or an electronic part.

10. A protected electrical line, comprising:

(a) wire or cable having an axial length and

(b) at least one layer of the compound of claim 1 enveloping the axial length of the wire or cable.

11. The protected electrical line of claim 10 in the form of a wire.

12. The protected electrical line of claim 10 in the form of a cable.