Flame-retardant poly(arylene ether) composition and its use as a covering for coated wire

1. A thermoplastic composition, comprising:

20 to 50 weight percent of a poly(arylene ether);

25 to 57 weight percent of total polyolefin; wherein total polyolefin consists of polyolefins and the polyolefin content of block copolymers comprising a poly(alkenyl aromatic) block and a polyolefin block; and

3 to 30 weight percent of a flame retardant composition comprising a metal dialkyl phosphinate;

wherein all weight percents are based on the total weight of the thermoplastic composition;

wherein the poly(arylene ether) and total polyolefin are present in a weight ratio of 0.53:1 to 1.2:1; and

wherein a test sample coated wire exhibits

a tensile stress at break of at least 10 megapascals, measured at 23° C. according to UL 1581, Section 470,

a tensile elongation at break of at least 100 percent, measured at 23° C. according to UL 1581, Section 470, and

a passing flame test rating according to UL 1581, Section 1080,

wherein the test sample coated wire consists of an AWG 24 conductor having a nominal cross sectional area of 0.205 millimeter 2 , and a tubular covering comprising the thermoplastic composition and having a nominal outer diameter of 2 millimeters.

2. The thermoplastic composition of claim 1 ,

wherein the thermoplastic composition comprises 20 to 44 weight percent of the poly(arylene ether);

wherein the thermoplastic composition comprises 29 to 57 weight percent of total polyolefin;

wherein the thermoplastic composition comprises 10 to 25 weight percent of the flame retardant composition;

wherein the flame retardant composition comprises 1 to 10 weight percent of the metal dialkyl phosphinate; and

wherein the flame retardant composition further comprises

1 to 17 weight percent of a nitrogen-containing flame retardant selected from the group consisting of melamine phosphate, melamine pyrophosphate, melamine polyphosphates, and mixtures thereof, and

1 to 10 weight percent of a triaryl phosphate that is a liquid at one atmosphere and at least one temperature in the range 25 to 50° C.

3. The thermoplastic composition of claim 2 , wherein the test sample coated wire exhibits

a tensile stress at break of 10 to 30 megapascals, measured at 23° C. according to UL1581, Section 470, and

a tensile elongation at break of 100 to 240 percent, measured at 23° C. according to UL1581, Section 470.

4. The thermoplastic composition of claim 2 , wherein the test sample coated wire further exhibits a triaryl phosphate migration rating of 0, 1, or 2, measured as described in the working examples.

5. The thermoplastic composition of claim 2 , wherein the test sample coated wire further exhibits a heat deformation of 5 to 40 percent, measured at 121° C. and a 250 gram load according to UL 1581.

6. The thermoplastic composition of claim 2 , wherein the liquid triaryl phosphate represents 10 to 70 percent of the total weight of the flame retardant composition.

7. The thermoplastic composition of claim 2 , wherein the nitrogen-containing flame retardant and the metal dialkyl phosphate are present in a weight ratio of 0.5 to 8.

8. The thermoplastic composition of claim 2 , wherein the flame retardant composition consists of the metal dialkyl phosphinate, the nitrogen-containing flame retardant, and the liquid triaryl phosphate.

9. The thermoplastic composition of claim 2 , wherein the flame retardant composition further comprises 0.05 to 2.5 weight percent zinc borate.

10. The thermoplastic composition of claim 2 , further comprising 8 to 20 weight percent of total poly(alkenyl aromatic); wherein total poly(alkenyl aromatic) consists of poly(alkenyl aromatic)s and the poly(alkenyl aromatic) content of block copolymers comprising a poly(alkenyl aromatic) block and a polyolefin block.

11. The thermoplastic composition of claim 2 ,

wherein the thermoplastic composition comprises 30 to 36 weight percent of the poly(arylene ether);

wherein the poly(arylene ether) is a poly(2,6-dimethyl-1,4-phenylene ether) having an intrinsic viscosity of 0.3 to 0.6 deciliter per gram measured in chloroform at 25° C.;

wherein the thermoplastic composition comprises 38 to 46 weight percent of total polyolefin weight percent of total polyolefin;

wherein the total polyolefin comprises polypropylene, ethylene-propylene copolymer, a poly(ethylene-co-propylene) block of a block copolymer comprising a polystyrene block and a poly(ethylene-co-propylene) block, and a poly(ethylene-co-butylene) block of a block copolymer comprising a polystyrene block and a poly(ethylene-co-butylene) block;

wherein the thermoplastic composition comprises 10 to 14 weight percent of the flame retardant composition consisting of

1 to 3 weight percent of aluminum tris(diethyl phosphinate),

1 to 3 weight percent of melamine polyphosphate, and

6 to 10 weight percent of bisphenol A bis(diphenyl phosphate);

wherein the poly(arylene ether) and total polyolefin are present in a weight ratio of 0.6 to 0.9; and

wherein the test sample coated wire exhibits

a tensile stress at break of 10 to 30 megapascals, measured at 23° C. according to UL1581, Section 470, and

a tensile elongation at break of 100 to 240 percent, measured at 23° C. according to UL1581, Section 470.

12. The thermoplastic composition of claim 2 ,

wherein the thermoplastic composition exhibits

a UL 94 Vertical Burning Flame Test rating of V-0 or V-1 at a sample thickness less than or equal to 6.4 millimeters,

a tensile stress at break of at least 5 megapascals, measured at 23° C. according to ASTM D638, and

a flexural modulus of 10 to 1,000 megapascals, measured at 23° C. according to ASTM D790.

13. The thermoplastic composition of claim 12 ,

wherein the UL 94 Vertical Burning Flame Test is conducted at a sample thickness of 3.0 to 6.4 millimeters, and

wherein the tensile stress at break is 5 to 21 megapascals.

14. The thermoplastic composition of claim 2 ,

wherein the thermoplastic composition comprises 30 to 36 weight percent of the poly(arylene ether);

wherein the poly(arylene ether) is a poly(2,6-dimethyl-1,4-phenylene ether) having an intrinsic viscosity of 0.3 to 0.6 deciliter per gram measured in chloroform at 25° C.;

wherein the thermoplastic composition comprises 38 to 46 weight percent of total polyolefin weight percent of total polyolefin;

wherein the total polyolefin comprises polypropylene, ethylene-propylene copolymer, and a poly(ethylene-co-butylene) block of a block copolymer comprising a polystyrene block and a poly(ethylene-co-butylene) block;

wherein the thermoplastic composition comprises 10 to 14 weight percent of the flame retardant composition consisting of

1 to 3 weight percent of aluminum tris(diethyl phosphinate),

1 to 3 weight percent of melamine polyphosphate, and

6 to 10 weight percent of bisphenol A bis(diphenyl phosphate);

wherein the poly(arylene ether) and total polyolefin are present in a weight ratio of 0.6 to 0.9; and

wherein the thermoplastic composition exhibits

a UL 94 Vertical Burning Flame Test rating of V-0 or V-1 at a sample thickness of 6.4 millimeters,

a tensile stress at break of 12 to 21 megapascals, measured at 23° C. according to ASTM D638, and

a flexural modulus of 50 to 310 megapascals, measured at 23° C. according to ASTM D790.

15. The thermoplastic composition of claim 1 ,

wherein the thermoplastic composition comprises 3 to 25 weight percent of the flame retardant composition;

wherein the flame retardant composition comprises 1 to 15 weight percent of the metal dialkyl phosphinate;

wherein the flame retardant composition further comprises 1 to 20 weight percent of a nitrogen-containing flame retardant selected from the group consisting of melamine phosphate, melamine pyrophosphate, melamine polyphosphates, and mixtures thereof;

wherein the poly(arylene ether) and total polyolefin are present in a weight ratio of 0.56:1 to 1.2:1; and

wherein the nitrogen-containing flame retardant and the metal dialkyl phosphinate are present in a ratio of 0.2:1 to 5:1.

16. The thermoplastic composition of claim 15 , wherein the flame retardant composition excludes triaryl phosphates that are liquids at one atmosphere and at least one temperature in the range 25 to 50° C.

17. The thermoplastic composition of claim 16 , wherein the test sample coated wire exhibits

a tensile stress at break of 10 to 30 megapascals, measured at 23° C. according to UL1581, Section 470, and

a tensile elongation at break of 100 to 350 percent, measured at 23° C. according to UL1581, Section 470.

18. The thermoplastic composition of claim 16 , wherein the test sample coated wire further exhibits a heat deformation of 5 to 50 percent, measured at 121° C. and a 250 gram load according to UL 1580.

19. The thermoplastic composition of claim 16 , wherein the flame retardant composition consists of the metal dialkyl phosphinate and the nitrogen-containing flame retardant.

20. The thermoplastic composition of claim 16 , wherein the flame retardant composition further comprises 0.05 to 2.5 weight percent zinc borate.

21. The thermoplastic composition of claim 16 , further comprising 3 to 20 weight percent of total poly(alkenyl aromatic); wherein total poly(alkenyl aromatic) consists of poly(alkenyl aromatic)s and the poly(alkenyl aromatic) content of block copolymers comprising a poly(alkenyl aromatic) block and a polyolefin block.

22. The thermoplastic composition of claim 16 ,

wherein the thermoplastic composition comprises 37 to 47 weight percent of the poly(arylene ether);

wherein the poly(arylene ether) is a poly(2,6-dimethyl-1,4-phenylene ether) having an intrinsic viscosity of 0.3 to 0.6 deciliter per gram measured in chloroform at 25° C.;

wherein the thermoplastic composition comprises 34 to 43 weight percent of total polyolefin weight percent of total polyolefin;

wherein the total polyolefin comprises polypropylene, polybutene, ethylene-propylene copolymer, a poly(ethylene-co-propylene) block of a block copolymer comprising a polystyrene block and a poly(ethylene-co-propylene) block, and a poly(ethylene-co-butylene) block of a block copolymer comprising a polystyrene block and a poly(ethylene-co-butylene) block;

wherein the thermoplastic composition comprises 4 to 12 weight percent of the flame retardant composition consisting of

2 to 6 weight percent of aluminum tris(diethyl phosphinate), and

2 to 6 weight percent of melamine polyphosphate;

wherein the poly(arylene ether) and total polyolefin are present in a weight ratio of 0.8 to 1.2; and

wherein the test sample coated wire exhibits

a tensile stress at break of 10 to 25 megapascals, measured at 23° C. according to UL1581, Section 470, and

a tensile elongation at break of 200 to 300 percent, measured at 23° C. according to UL1581, Section 470.

23. The thermoplastic composition of claim 16 ,

wherein the thermoplastic composition comprises 6 to 25 weight percent of the flame retardant composition;

wherein the poly(arylene ether) and total polyolefin are present in a weight ratio of 0.68:1 to 1.2:1;

wherein the metal dialkyl phosphinate and the nitrogen-containing flame retardant are present in a weight ratio of at least 5:1; and

wherein the thermoplastic composition exhibits

a UL 94 Vertical Burning Flame Test rating of V-0 or V-1 at a sample thickness less than or equal to 6.4 millimeters,

a tensile stress at break of at least 5 megapascals measured at 23° C. according to ASTM D638, and

a flexural modulus of 10 to 1,000 megapascals measured at 23° C. according to ASTM D790.

24. The thermoplastic composition of claim 1 ,

wherein the flame retardant composition further comprises a triaryl phosphate that is a liquid at one atmosphere and at least one temperature in the range 25 to 50° C.; and

wherein the poly(arylene ether) and total polyolefin are present in a weight ratio of 0.55:1 to 1.2:1.

25. The thermoplastic composition of claim 24 , wherein the flame retardant composition excludes melamine phosphate, melamine pyrophosphate, and melamine polyphosphate.

26. The thermoplastic composition of claim 25 , wherein the test sample coated wire exhibits

a tensile stress at break of 10 to 25 megapascals, measured at 23° C. according to UL1581, Section 470, and

a tensile elongation at break of 100 to 360 percent, measured at 23° C. according to UL1581, Section 470.

27. The thermoplastic composition of claim 25 , wherein the test sample coated wire further exhibits a heat deformation of 5 to 20 percent, measured at 121° C. and a 250 gram load according to UL 1580.

28. The thermoplastic composition of claim 25 , further comprising 3 to 20 weight percent of total poly(alkenyl aromatic); wherein total poly(alkenyl aromatic) consists of poly(alkenyl aromatic)s and the poly(alkenyl aromatic) content of block copolymers comprising a poly(alkenyl aromatic) block and a polyolefin block.

29. The thermoplastic composition of claim 25 ,

wherein the thermoplastic composition comprises 39 to 47 weight percent of the poly(arylene ether);

wherein the poly(arylene ether) is a poly(2,6-dimethyl-1,4-phenylene ether) having an intrinsic viscosity of 0.3 to 0.6 deciliter per gram measured in chloroform at 25° C.;

wherein the thermoplastic composition comprises 35 to 42 weight percent of total polyolefin weight percent of total polyolefin;

wherein the total polyolefin comprises polypropylene, polybutene, ethylene-propylene copolymer, a poly(ethylene-co-propylene) block of a block copolymer comprising a polystyrene block and a poly(ethylene-co-propylene) block, and a poly(ethylene-co-butylene) block of a block copolymer comprising a polystyrene block and a poly(ethylene-co-butylene) block;

wherein the thermoplastic composition comprises 4 to 10 weight percent of the flame retardant composition consisting of aluminum tris(diethyl phosphinate);

wherein the poly(arylene ether) and total polyolefin are present in a weight ratio of 0.9 to 1.2; and

wherein the test sample coated wire exhibits

a tensile stress at break of 10 to 25 megapascals, measured at 23° C. according to UL1581, Section 470, and

a tensile elongation at break of 150 to 300 percent, measured at 23° C. according to UL1581, Section 470.

30. The thermoplastic composition of claim 1 , wherein the flame retardant composition consists of the metal dialkyl phosphinate.

31. An extruded article, comprising the product of extrusion molding the thermoplastic composition of claim 1 .

32. A coated wire, comprising:

a conductor, and

a covering disposed on the conductor;

wherein the covering comprises the thermoplastic composition of any of claim 1 .