| abstract |
(57) Abstract: To purify high molecular weight polyethers. SOLUTION: Water (B), acidic pyrophosphate (C), and a nonionic surfactant are added to a polyether (A) containing an alkali metal halide, water is removed, and then a polyether ( In the method for purifying a polyether, which comprises removing a metal salt insoluble in A) from the polyether (A), the pH of the polyether (A) before the addition of the acidic pyrophosphate (C) is adjusted to 2 to 12. adjust. |