Halogen-containing flame retardant polyamide compositions
Flame retardant thermoplastic polyamide compositions are described that provide a superior combination of glow wire ignition and elongation/toughness properties, comprising a polyamide resin; a bromine-containing flame retardant; a hindered phenolic heat stabilizer; and optionally at least one of a flame retardant synergist, a plasticizer, a lubricant, a mold release agent, an acid scavenger and a colorant.
1. A flame retardant polyamide composition consisting of:
at least 65% by weight of PA6,6 or PA6,6/6 or a combination thereof:
a bromine-containing flame retardant;
a hindered phenolic heat stabilizer;
1-8% by weight of a flame retardant synergist;
0-5% by weight of a colorant;
0-5% by weight of a lubricant;
0-5% by weight of a mold release agent;
0-5% by weight of an acid scavenger;
0-5% by weight of a plasticizer;
wherein the percentages are based on the total weight of the polyamide composition;
wherein the polyamide composition exhibits a glow wire ignition temperature greater than 850° C. and an elongation at break greater than 13%.
2. The polyamide composition according to claim 1 , wherein the polyamide resin is PA-6,6.
3. The polyamide composition according to claim 1 , wherein the bromine-containing flame retardant is bis(pentabromophenyl)ethane.
4. The polyamide composition according to claim 1 , wherein the hindered phenolic heat stabilizer is N,N′-hexamethylenebis(3,5-di-tert-butyl-4-hydroxy-hydrocinnamamide).
5. The polyamide composition according to claim 1 , wherein the flame retardant synergist is diantimony trioxide.
6. The polyamide composition according to claim 1 , wherein a plasticizer is present.
7. The polyamide composition according to claim 6 , wherein the plasticizer is diundecyl phthalate.
8. The polyamide composition according to claim 1 , wherein a lubricant or a mold release agent or a combination thereof is present.
9. The polyamide composition according to claim 1 , wherein a colorant is present.
10. The polyamide composition according to claim 1 , wherein the composition consists of:
65-85% by weight of the PA6,6 or PA6,6/6 or a combination thereof;
5-35% by weight of the bromine-containing flame retardant; and
0.01-5% by weight of the hindered phenolic heat stabilizer.
11. An article obtained from the polyamide composition according to claim 10 .
12. The article according to claim 11 , where the article is an electrical or electronic part.
13. An article obtained from the polyamide composition according to claim 1 .
14. The article according to claim 13 , where the article is an electrical or electronic part.