| 摘要 |
PURPOSE:To obtain a granular polymer having sharp distribution of particle size and excellent heat stability by coagulating a specified amount of the polymer in a specified latex with an acid and completing the coagulation at a specified pH by further addition of the acid. CONSTITUTION:40-80wt.% polymer in a latex containing an anionic sulfuric ester and/or sulfonic acid surfactant in an amount of 0.05-0.15 pts.wt. based on 100 pts.wt. polymer is coagulated with an acid, and the coagulation is completed at a pH of 2.0 or higher by further adding the acid, thus giving the objective granular polymer. It is desirable to add the acid in such a manner that the pH at the first-step coagulation satisfies the condition of the formula. In the formula, X is the amount (parts by weight) of the surfactant based on 100 pts.wt. polymer. |
