| 摘要 |
Provided are a medical polyoxypropylene polymer and polyoxypropylene/polyoxyethylene block copolymer which have low unsaturated ether content and in which coloring is suppressed. (A) To a polyoxypropylene polymer which comprises an aryl ether as an impurity and which is obtained by ring-opening polymerization of propylene oxide to a starting material having active hydrogen that reacts with propylene oxide, an alkali metal tertiary alkoxide is added in excess with respect to the number of moles of the active hydrogen in the starting material, the result is heat treated at 115°C or less, and the aryl ether is isomerized to a propenyl ether. (B) A mineral acid is added to the mixture obtained in step (A) to adjust pH to 4 or less, and the mixture is treated at 70°C or less to hydrolyze the propenyl ether. |
