Polybutylene terephthalate resin composition and molded article
Provided is a polybutylene terephthalate resin composition containing, with respect to 100 parts by mass of (A) a polybutylene terephthalate resin, (B) a total of 30 to 60 parts by mass of at least two different brominated flame retardants selected from the group consisting of a brominated epoxy compound, a brominated polycarbonate compound and a brominated polystyrene compound, (C) 5 to 15 parts by mass of an antimony compound, (D) 5 to 30 parts by mass of an elastomer, and (E) 0.5 to 3 parts by mass of a mold-release agent.
1. A polybutylene terephthalate resin composition, comprising:
(A) 100 parts by mass of a polybutylene terephthalate resin,
(B) a total of 30 to 60 parts by mass of at least two different brominated flame retardants selected from the group consisting of a brominated epoxy compound, a brominated polycarbonate compound and a brominated polystyrene compound,
(C) 5 to 15 parts by mass of an antimony compound,
(D) 5 to 30 parts by mass of an elastomer, and
(E) 0.5 to 3 parts by mass of a mold-release agent,
wherein the polybutylene terephthalate resin composition has a crystallization temperature of from 175 to 193° C.
2. The polybutylene terephthalate resin composition of claim 1 , wherein the at least two different brominated flame retardants (B) comprise:
a brominated flame retardant (B1), which is selected from among a brominated epoxy compound and a brominated polycarbonate compound and which has a weight average molecular weight of 1000 to 8000, and
a brominated flame retardant (B2), which is selected from among a brominated epoxy compound and a brominated polystyrene compound and which has a weight average molecular weight of more than 8000 to 70000.
3. The polybutylene terephthalate resin composition of claim 1 , wherein the polybutylene terephthalate resin composition has a crystallization temperature of from 180 to 193° C.
4. The polybutylene terephthalate resin composition of claim 1 , wherein the at least two different brominated flame retardants (B) are each independently a brominated epoxy compound.
5. The polybutylene terephthalate resin composition of claim 1 , comprising a brominated epoxy compound, wherein the brominated epoxy compound is terminally capped by tribromophenol.
6. The polybutylene terephthalate resin composition of claim 2 , wherein a mass ratio (B1)/(B2) of the flame retardant (B1) and the flame retardant (B2) is 90/10 to 30/70.
7. The polybutylene terephthalate resin composition of claim 1 , wherein the elastomer (D) is an ethylenic elastomer.
8. The polybutylene terephthalate resin composition of claim 7 , wherein the ethylenic elastomer is an ethylene-alkyl acrylate ester-glycidyl methacrylate copolymer.
9. The polybutylene terephthalate resin composition of claim 1 , wherein the mold-release agent (E) is a montanic acid ester mold-release agent.
10. The polybutylene terephthalate resin composition of claim 1 , wherein a moisture content of the polybutylene terephthalate resin composition is 500 ppm or less.
11. A molded article, comprising the polybutylene terephthalate resin composition of claim 1 .
12. A vehicular electrical component, comprising the molded article of claim 11 .
13. The polybutylene terephthalate resin composition of claim 1 , which is free of a polycarbonate resin.