| 摘要 |
The invention relates to a process for the preparation of modified silicon dioxide which can be used in rubber and tire industry. The process involves the preparation of colloidal sol of silicon dioxide at thorough stirring followed by residue filtration and drying. The colloidal sol of silicon dioxide is prepared at pH 9.4-9.6, stirred for 5-20 min., solution of carbamide and formaldehyde is prepared separately at component ratio of 1:1.2-1.5, correspondingly, with following addition of the solution to the colloidal sol with simultaneous addition of sulphuric acid to pH of 2.0-3.0 at temperature of 80-85°С and stirring for 30-60 min. The invention allows to prepare silicon dioxide with high dispersiveness and particles size of 0.4-. |
