| 摘要 |
Process for the production of a white fine-grained material of urea-formaldehyde resin or a modified urea-formaldehyde resin. The process comprises reacting urea with formaldehyde at a molar ration of urea:formaldehyde between 1:0.4 and 1:2.5 at a temperature between 15 and 100 DEG C and at a pH between about 0.5 and 3.0, preferably between 0.8 and 2.0. Precipitated particles of urea resin being insoluble in the reaction mixture are then formed as a slurry. |
