Low-halogen flame retardant polyamide compositions resistant to heat aging
The present invention relates to a low-halogen flame retardant thermoplastic polyamide composition that provides improved mechanical and electrical stability at elevated temperatures, where the thermoplastic composition comprises a polyamide resin; a non-halogen, nitrogen-containing flame retardant; a heat stabilizer containing a copper halide and an organophosphorus compound; an optional lubricant and/or mold release agent; and an optional colorant.
1. A low-halogen thermoplastic polyamide composition comprising:
a polyamide resin;
a non-halogen flame retardant, wherein the non-halogen flame retardant is a melamine salt or a melamine adduct; and
0.03-2.5% by weight of a copper-containing heat stabilizer comprising a copper halide and an organophosphorus compound,
wherein the polyamide composition has an elemental bromine content of greater than 900 ppm but less than 1300 ppm.
2. The thermoplastic polyamide composition according to claim 1 , wherein the polyamide resin is selected from the group consisting of PA-4,6; PA-6,I; PA-6,T; PA-6,6; PA-6/6,6; and a mixture thereof.
3. The thermoplastic polyamide composition according to claim 1 , wherein the polyamide resin is PA-6,6.
4. The thermoplastic polyamide composition according to claim 1 , wherein the melamine salt or a melamine adduct is melamine cyanurate or melamine polyphosphate.
5. The thermoplastic polyamide composition according to claim 1 , wherein the copper halide and the organophosphorus compound form a complex.
6. The thermoplastic polyamide composition according to claim 1 , wherein the organophosphorus compound is triphenylphosphine or triphenylphosphite.
7. The thermoplastic polyamide composition according to claim 5 , wherein the copper halide is copper(I) halide, and wherein the organophosphorus compound is bis(triphenylphosphine) or bis(triphenylphosphite).
8. The thermoplastic polyamide composition according to claim 1 , wherein the copper halide is copper(I) iodide.
9. The thermoplastic polyamide composition according to claim 1 , further comprising a lubricant or mold release agent.
10. The thermoplastic polyamide composition according to claim 9 , wherein the lubricant or mold release agent is a stearic acid salt.
11. The thermoplastic polyamide composition according to claim 1 , further comprising a colorant.
12. The thermoplastic polyamide composition according to claim 1 , further comprising an additional copper-containing heat stabilizer.
13. A low-halogen thermoplastic polyamide composition comprising:
a polyamide resin;
a non-halogen flame retardant, wherein the non-halogen flame retardant is a melamine salt or a melamine adduct; and
0.03-2.5% by weight of a copper-containing heat stabilizer comprising a copper halide and an organophosphorus compound,
wherein the polyamide composition has a maximum elemental bromine content of 900 ppm.
14. The thermoplastic polyamide composition according to claim 1 , comprising:
50-95% by weight of the polyamide resin;
1-20% by weight of the melamine salt or the melamine adduct;
0.03-2.5% by weight of the heat stabilizer, wherein the copper halide and the organophosphorus compound form a complex;
0-10% by weight of a lubricant or mold release agent; and
0-10% by weight of a colorant.
15. The thermoplastic polyamide composition according to claim 14 , wherein the polyamide resin is PA-6,6; wherein the copper halide is copper(I) halide;
and wherein the organophosphorus compound is bis(triphenylphosphine).
16. The thermoplastic polyamide composition according to claim 14 , wherein the melamine salt or melamine adduct is melamine cyanurate or melamine polyphosphate.
17. The thermoplastic polyamide composition according to claim 14 , wherein the lubricant/mold release agent is a stearic acid salt.
18. The thermoplastic polyamide composition according to claim 14 , wherein the colorant is carbon black.
19. An article obtained from the thermoplastic polyamide composition according to claim 1 .
20. The article according to claim 19 , where the article is an automotive part.
21. The article according to claim 19 , where the article is an electric or electronic part.
22. The thermoplastic polyamide composition according to claim 1 , wherein the melamine salt or the melamine adduct is melamine cyanurate.
23. The thermoplastic polyamide composition according to claim 1 , comprising 7-20% by weight of the melamine salt or the melamine adduct.