Flame retardant thermoplastic elastomer compositions

1. A flame retardant thermoplastic elastomer composition comprising;

(a) about 70 to about 99 weight percent of a melt-processable thermoplastic vulcanizate composition comprising:

(i) from about 15 to about 75 weight percent of at least one thermoplastic polyester continuous phase; and

(ii) from about 25 to about 85 weight percent of at least one poly(meth)acrylate or polyethylene/(meth)acrylate rubber disperse phase wherein said rubber is dynamically cross-linked with at least one peroxide free-radical initiator and at least one organic multiolefinic co-agent; and

(b) about 1 to about 30 weight percent, of at least one flame retardant comprising a phosphinate of the formula (I) and/or a disphosphinate of the formula (II) and/or polymers of thereof

wherein R 1 and R 2 are identical or different and are hydrogen, C 1 -C 6 alkyl, linear or branched, and/or aryl; R 3 is C 1 -C 10 -alkylene, linear or branched, C 6 -C 10 -arylene, -alkylarylene or -arylalkylene; M is calcium ions, magnesium ions, aluminum ions, and/or zinc ions, m is 2 to 3; n is 1 or 3; and x is 1 or 2,

wherein the weight percentages of (a) and (b) are based on the total weight of (a)+(b) and the weight percentages of (i) and (ii) are based on the total weight of (i)+(ii).

2. The thermoplastic elastomer composition of claim 1 , wherein the flame retardant is aluminum phosphinate, aluminum diethyl phosphinate and/or zinc diethyl phosphinate.

3. The thermoplastic elastomer composition of claim 1 , wherein the flame retardant has a particle size (D90 value) less than or equal to 100 microns.

4. The thermoplastic elastomer composition of claim 1 , wherein the flame retardant has a particle size (D90 value) less than or equal to 20 microns.

5. The thermoplastic elastomer composition of claim 1 , wherein thermoplastic vulcanizate composition (a) is present in about 80 to about 98 weight percent and flame retardant (b) is present in about 2 to about 20 weight percent.

6. The thermoplastic elastomer composition of claim 1 , wherein thermoplastic vulcanizate composition (a) is present in about 85 to about 97 weight percent and flame retardant (b) is present in about 3 to about 15 weight percent.

7. The thermoplastic elastomer composition of claim 1 , wherein the thermoplastic vulcanizate comprises about 15 to about 60 weight percent of component (i) and about 40 to about 85 weight percent of component (ii).

8. The thermoplastic elastomer composition of claim 1 further comprising one or more heat stabilizers and/or antioxidants.

9. The thermoplastic elastomer composition of claim 1 further comprising one or more surface modifiers and/or metal deactivators.

10. The thermoplastic elastomer composition of claim 8 further comprising one or more surface modifiers and/or metal deactivators.

11. The thermoplastic elastomer composition of claim 1 further comprising one or more amorphous polymers.

12. The thermoplastic elastomer composition of claim 11 , wherein the one or more amorphous polymers are polycarbonate, poly(methyl (meth)acrylate), and/or polyarylates.

13. The thermoplastic elastomer composition of claim 11 further comprising one or more surface modifiers and/or metal deactivators and/or heat stabilizers and/or antioxidants.

14. The thermoplastic elastomer composition of claim 1 , wherein the thermoplastic polyester continuous phase (i) comprises at least one copolyetherester elastomer.

15. The thermoplastic elastomer composition of claim 14 , wherein the copolyetherester elastomer is prepared from monomers comprising poly(tetramethylene oxide) glycol; isophthalic acid and/or terephthalic acid; and 1,4-butanediol and/or 1,3-propanediol.

16. The thermoplastic elastomer composition of claim 14 , wherein the copolyetherester elastomer is prepared from monomers comprising poly(trimethylene oxide) glycol; isophthalic acid and/or terephthalic acid; and 1,4-butanediol and/or 1,3-propanediol.

17. The thermoplastic elastomer composition of claim 1 , wherein the free-radical initiator is one or more of 2,5-dimethyl-2,5-di-(t-butylperoxy)-3-hexyne; t-butyl peroxybenzoate; 2,5-dimethyl-2,5-di-(t-butylperoxy)-2,5-dimethylhexane; dicumyl peroxide; and α,α-bis(t-butylperoxy)-2,5-dimethylhexane.

18. The thermoplastic elastomer composition of claim 1 , wherein the organic multifunctional cross-linking co-agent is one or more of diethyleneglycol diacrylate; diethyleneglycol dimethacrylate; N,N′-m-phenylene dimaleimide; triallylisocyanurate; trimethylolpropane trimethacrylate; tetraallyloxyethane; triallyl cyanurate; tetramethylene diacrylate; and polyethylene glycol dimethacrylate.

19. The thermoplastic elastomer composition of claim 1 , wherein the rubber disperse phase comprises at least one poly(perfluoroalkyl (meth)acrylate).

20. A molded, extruded, or shaped article comprising the composition of claim 1 .

21. A wire or cable comprising a coating comprising the composition of claim 1 .

22. An automotive primary cable comprising a coating comprising the composition of claim 1 .

23. A molded, extruded, or shaped article comprising the composition of claim 11 .

24. A wire or cable comprising a coating comprising the composition of claim 11 .

25. An automotive primary cable comprising a coating comprising the composition of claim 11 .