| 摘要 |
Provided is a method for reacting a resin with sulfuric acid comprising the step of heating a reaction mixture to a temperature of 80°C or higher, wherein said reaction mixture comprises (a) a collection of copolymer particles (A), (b) sulfuric acid, and (c) a collection of solid particles (B) different from said copolymer particles (A), wherein said solid particles (B) have BET surface area of 50 m2/g to 5,000 m2/g. |
