Polyphenylene ether and method for producing the same

1. A polyphenylene ether, comprising a content of a metal magnetic material of 0.001 ppm or higher and lower than 1.000 ppm.

2. The polyphenylene ether according to claim 1 , wherein the polyphenylene ether comprises a content of a metal magnetic material of 0.001 ppm or higher and lower than 0.500 ppm.

3. The polyphenylene ether according to claim 1 , wherein the polyphenylene ether comprises a content of a metal magnetic material of 0.001 ppm or higher and lower than 0.100 ppm.

4. The polyphenylene ether according to claim 1 , wherein the metal magnetic material is a metal magnetic material comprising an Fe element.

5. The polyphenylene ether according to claim 4 , wherein the polyphenylene ether comprises a content of the Fe element of 0.001 ppm or higher and lower than 0.100 ppm.

6. The polyphenylene ether according to claim 4 , wherein the polyphenylene ether is a powder having a volume-average particle diameter of 3 mm or smaller.

7. The polyphenylene ether according to claim 1 , wherein the polyphenylene ether is a powder having a loose apparent specific gravity of 0.4 or higher.

8. The polyphenylene ether according to claim 1 , wherein the polyphenylene ether is a powder having a specific surface area of 1 m 2 /g or larger.

9. The polyphenylene ether according to claim 1 , wherein a whole metal magnetic material comprises a content of the metal magnetic material having a maximum breadth of 150 μm or larger of 0.1 particle/kg or lower.

10. The polyphenylene ether according to claim 1 , wherein the polyphenylene ether has a C. I. heat (a color index value of a polyphenylene ether compressed at 310° C. for 20 min at a pressure of 10 MPa) of 3.5 or lower.

11. A method for producing a polyphenylene ether, comprising the steps of:

polymerizing a phenol compound so as to obtain a polyphenylene ether represented by the following formula (1); and

passing the polyphenylene ether through a magnetic separating machine equipped with a magnetic force-generating source so as to make a content of a metal magnetic material in the polyphenylene ether to be 0.001 ppm or higher and lower than 1.000 ppm:

wherein R 1 , R 2 , R 3 and R 4 each independently represents one selected from the group consisting of a hydrogen atom, a halogen atom, an alkyl group which may be substituted, an aryl group which may be substituted, an aralkyl group which may be substituted, and an alkoxy group which may be substituted.

12. The method for producing the polyphenylene ether according to claim 11 , comprising:

passing the polyphenylene ether through a magnetic separating machine equipped with a magnetic force-generating source so as to make a content of a metal magnetic material in the polyphenylene ether to be 0.001 ppm or higher and lower than 0.500 ppm.

13. The method for producing the polyphenylene ether according to claim 11 , comprising:

passing the polyphenylene ether through a magnetic separating machine equipped with a magnetic force-generating source so as to make a content of a metal magnetic material in the polyphenylene ether to be 0.001 ppm or higher and lower than 0.100 ppm.

14. The method for producing the polyphenylene ether according to claim 11 , wherein the metal magnetic material is a metal magnetic material comprising an Fe element.

15. The method for producing the polyphenylene ether according to claim 14 , wherein the polyphenylene ether is a powder having a volume-average particle diameter of 3 mm or smaller.

16. The method for producing the polyphenylene ether according to claim 11 , wherein the polyphenylene ether is a powder having a loose apparent specific gravity of 0.4 or higher.

17. The method for producing the polyphenylene ether according to claim 11 , wherein the polyphenylene ether is a powder having a specific surface area of 1 m 2 /g or larger.

18. The method for producing the polyphenylene ether according to claim 11 , wherein when the polyphenylene ether is passed through the magnetic separating machine equipped with the magnetic force-generating source, a magnetic force in a region for removing a metal magnetic material from the polyphenylene ether is 0.6 T or higher.

19. The method for producing the polyphenylene ether according to claim 11 , wherein the magnetic force-generating source of the magnetic separating machine is an electromagnet.

20. The method for producing the polyphenylene ether according to claim 11 , wherein the polyphenylene ether is passed through between the magnetic force-generating source arranged with a spacing of 15 mm or smaller.

21. The method for producing the polyphenylene ether according to claim 11 , wherein the magnetic separating machine has a magnetic force-effective separation length of 100 mm or longer.

22. The polyphenylene ether according to claim 2 , wherein the metal magnetic material is a metal magnetic material comprising an Fe element.

23. The polyphenylene ether according to claim 3 , wherein the metal magnetic material is a metal magnetic material comprising an Fe element.

24. The polyphenylene ether according to claim 22 , wherein the polyphenylene ether comprises a content of the Fe element of 0.001 ppm or higher and lower than 0.100 ppm.

25. The polyphenylene ether according to claim 23 , wherein the polyphenylene ether comprises a content of the Fe element of 0.001 ppm or higher and lower than 0.100 ppm.

26. The polyphenylene ether according to claim 22 , wherein the polyphenylene ether is a powder having a volume-average particle diameter of 3 mm or smaller.

27. The polyphenylene ether according to claim 23 , wherein the polyphenylene ether is a powder having a volume-average particle diameter of 3 mm or smaller.

28. The polyphenylene ether according to claim 2 , wherein the polyphenylene ether is a powder having a loose apparent specific gravity of 0.4 or higher.

29. The polyphenylene ether according to claim 3 , wherein the polyphenylene ether is a powder having a loose apparent specific gravity of 0.4 or higher.

30. The polyphenylene ether according to claim 2 , wherein the polyphenylene ether is a powder having a specific surface area of 1 m 2 /g or larger.

31. The polyphenylene ether according to claim 3 , wherein the polyphenylene ether is a powder having a specific surface area of 1 m 2 /g or larger.

32. The polyphenylene ether according to claim 2 , wherein a whole metal magnetic material comprises a content of the metal magnetic material having a maximum breadth of 150 μm or larger of 0.1 particle/kg or lower.

33. The polyphenylene ether according to claim 3 , wherein a whole metal magnetic material comprises a content of the metal magnetic material having a maximum breadth of 150 μm or larger of 0.1 particle/kg or lower.

34. The polyphenylene ether according to claim 2 , wherein the polyphenylene ether has a C. I. heat (a color index value of a polyphenylene ether compressed at 310° C. for 20 min at a pressure of 10 MPa) of 3.5 or lower.

35. The polyphenylene ether according to claim 3 , wherein the polyphenylene ether has a C. I. heat (a color index value of a polyphenylene ether compressed at 310° C. for 20 min at a pressure of 10 MPa) of 3.5 or lower.

36. The method for producing the polyphenylene ether according to claim 12 , wherein the metal magnetic material is a metal magnetic material comprising an Fe element.

37. The method for producing the polyphenylene ether according to claim 13 , wherein the metal magnetic material is a metal magnetic material comprising an Fe element.

38. The method for producing the polyphenylene ether according to claim 36 , wherein the polyphenylene ether is a powder having a volume-average particle diameter of 3 mm or smaller.

39. The method for producing the polyphenylene ether according to claim 37 , wherein the polyphenylene ether is a powder having a volume-average particle diameter of 3 mm or smaller.

40. The method for producing the polyphenylene ether according to claim 12 , wherein the polyphenylene ether is a powder having a loose apparent specific gravity of 0.4 or higher.

41. The method for producing the polyphenylene ether according to claim 13 , wherein the polyphenylene ether is a powder having a loose apparent specific gravity of 0.4 or higher.

42. The method for producing the polyphenylene ether according to claim 12 , wherein the polyphenylene ether is a powder having a specific surface area of 1 m 2 /g or larger.

43. The method for producing the polyphenylene ether according to claim 13 , wherein the polyphenylene ether is a powder having a specific surface area of 1 m 2 /g or larger.

44. The method for producing the polyphenylene ether according to claim 12 , wherein when the polyphenylene ether is passed through the magnetic separating machine equipped with the magnetic force-generating source, a magnetic force in a region for removing a metal magnetic material from the polyphenylene ether is 0.6 T or higher.

45. The method for producing the polyphenylene ether according to claim 13 , wherein when the polyphenylene ether is passed through the magnetic separating machine equipped with the magnetic force-generating source, a magnetic force in a region for removing a metal magnetic material from the polyphenylene ether is 0.6 T or higher.

46. The method for producing the polyphenylene ether according to claim 12 , wherein the magnetic force-generating source of the magnetic separating machine is an electromagnet.

47. The method for producing the polyphenylene ether according to claim 13 , wherein the magnetic force-generating source of the magnetic separating machine is an electromagnet.

48. The method for producing the polyphenylene ether according to claim 12 , wherein the polyphenylene ether is passed through between the magnetic force-generating source arranged with a spacing of 15 mm or smaller.

49. The method for producing the polyphenylene ether according to claim 13 , wherein the polyphenylene ether is passed through between the magnetic force-generating source arranged with a spacing of 15 mm or smaller.

50. The method for producing the polyphenylene ether according to claim 12 , wherein the magnetic separating machine has a magnetic force-effective separation length of 100 mm or longer.

51. The method for producing the polyphenylene ether according to claim 13 , wherein the magnetic separating machine has a magnetic force-effective separation length of 100 mm or longer.