Phosphoric compound, method for preparing the same, and flame retardant thermoplastic resin composition including the same

1. A phosphoric compound represented by the following Chemical Formula 1:

wherein R 1 is phenyl and each R 2 is the same or different and is independently C 1 -C 6 alkyl or aryl; and each m is 3.

2. The phosphoric compound of claim 1 , wherein each R 2 is independently C 1 -C 6 alkyl.

3. The phosphoric compound of claim 1 , wherein the phosphoric compound is bis(2,4,6-trimethylphenyl)phenyl phosphonate represented by the following Chemical Formula 3

4. A method for preparing a phosphoric compound represented by the following Chemical Formula 1

wherein R 1 is phenyl and each R 2 is the same or different and is independently C 1 -C 6 alkyl or aryl; and each m is the same or different and is independently an integer of 1 to 3, the method comprising:

reacting a compound or a combination of compounds represented by the following Chemical Formula 4 with a compound represented by the following Chemical Formula 5 in the presence of an organic amine compound:

wherein each R 2 is the same or different and is independently C 1 -C 6 alkyl or aryl; and each m is the same or different and is independently an integer of 1 to 3,

wherein R 1 is phenyl.

5. The method of claim 4 , wherein said organic amine compound is pyridine, triethylamine, or a mixture thereof.

6. The method of claim 4 , comprising reacting the compound represented by Chemical Formula 4 and the compound represented by Chemical Formula 5 in a molar ratio of about 2:1 to about 3:1.

7. The method of claim 4 , wherein the molar ratio of the organic amine compound to the compound represented by Chemical Formula 5 is about 2:1 to about 50:1.

8. The method of claim 4 , comprising:

reacting the compound or combination of compounds represented by Chemical Formula 4 with the compound represented by Chemical Formula 5 in the presence of an organic amine compound for about 10 to about 30 hours at a temperature of about 120 to about 160° C. while stirring and refluxing the reaction mixture;

removing unreacted organic amine compound by depressurizing the reaction product obtained by the reaction; and

filtering and drying the reaction product, from which the unreacted organic amine compound was removed, after washing the reaction product.

9. A flame retardant represented by the following Chemical Formula 1:

wherein R 1 is phenyl and each R 2 is the same or different and is independently C 1 -C 6 alkyl or aryl; and each m is 3.

10. A flame retardant thermoplastic resin composition comprising:

100 parts by weight of a thermoplastic resin; and

about 0.5 to about 30 parts by weight of a phosphoric compound represented by the following Chemical Formula 1:

wherein R 1 is phenyl and each R 2 is the same or different and is independently C 1 -C 6 alkyl or aryl; and each m is 3.

11. The flame retardant thermoplastic resin composition of claim 10 , wherein the phosphoric compound is bis(2,4,6-trimethylphenyl)phenyl phosphonate represented by the following Chemical Formula 3

12. The flame retardant thermoplastic resin composition of claim 10 , wherein the thermoplastic resin comprises an aromatic vinyl polymer resin including polystyrene resin (PS), rubber modified polystyrene resin (HIPS), aromatic vinyl-vinyl cyanide graft copolymer resin (ABS), vinyl cyanide-aromatic vinyl copolymer resin (SAN); polyphenylene ether resin, polyphenylene sulfide resin, polycarbonate resin, polyethylene resin, polypropylene resin, polyethylene terephthalate, polybutylene terephthalate, polymethylmethacrylate, polyamide resin, or a mixture thereof.

13. The flame retardant thermoplastic resin composition of claim 10 , wherein the thermoplastic resin comprises (A) about 80 to about 95% by weight of an aromatic vinyl polymer resin and (B) about 5 to about 20% by weight of a polyphenylene ether resin.

14. The flame retardant thermoplastic resin composition of claim 10 , further comprising about 1 to about 25 parts by weight of (D1) an aromatic phosphoric acid ester compound, (D2) an alkyl phosphinic acid metal salt compound, or a mixture thereof, based on 100 parts by weight of the thermoplastic resin.

15. The flame retardant thermoplastic resin composition of claim 14 , wherein the aromatic phosphoric acid ester compound (D1) has a structure of the following Chemical Formula 6:

wherein R 3 , R 4 , and R 5 are the same or different and are each independently hydrogen or C 1 -C 4 alkyl; X is C 6 -C 20 aryl or C 1 -C 4 alkyl-substituted C 6 -C 20 aryl and is derived from a dialcohol of resorcinol, hydroquinol, or bisphenol-A; and n is an integer of 0 to 4.

16. The flame retardant thermoplastic resin composition of claim 14 , wherein the alkyl phosphinic acid metal salt compound (D2) has a structure of the following Chemical Formula 7:

wherein each R is the same or different and is independently C 1 -C 6 alkyl, C 4 -C 6 cycloalkyl, or C 6 -C 10 aryl; M is a metal of Al, Zn, Mg or Ca; and n is an integer of 2 or 3.

17. The flame retardant thermoplastic resin composition of claim 10 , further comprising an additive selected from the group consisting of plasticizers, heat stabilizers, antioxidants, anti-dripping agents, compatibilizers, light-stabilizers, pigments, dyes, inorganic fillers and mixtures thereof.

18. The method of claim 4 , wherein each R 2 is independently C 1 -C 6 alkyl.

19. The method of claim 4 , wherein the phosphoric compound of Chemical Formula 1 is bis(4-tert-butylphenyl)phenyl phosphonate represented by the following Chemical Formula 2

20. The method of claim 4 , wherein the phosphoric compound of Chemical Formula 1 is bis(2,4,6-trimethylphenyl)phenyl phosphonate represented by the following Chemical Formula 3

21. The flame retardant thermoplastic resin composition of claim 10 , wherein each R 2 is independently C 1 -C 6 alkyl.