A kind of preparation method of surface modified silicon dioxide particle

Abstract

The invention belongs to the technical field of silicon dioxide and particularly relates to a surface modified silicon dioxide particle preparation method. The preparation method includes: S1, preparing a cationic polyacrylamide solution; S2, injecting a sodium bicarbonate solution and the cationic polyacrylamide solution into a reaction tank, controlling a stirring speed, dropwise adding a sodium silicate solution into the reaction tank at a normal temperature, adding a food-grade pigment solution when the sodium silicate solution is half added, and after the sodium silicate solution is completely added, stirring until a material system is converted into gel; S3, adding dilute sulfuric acid, and stopping adding the acid when a final pH value of the system is controlled to be 4-5; S4, subjecting silicon dioxide gel to filter pressing, washing, drying and grinding to obtain silicon dioxide particles. The surface modified silicon dioxide particle preparation method is simple, low in cost and low in pollution, and the silicon dioxide particles prepared according ot the method is low in density and long in suspension time.

Description

technical field [0001] The invention belongs to the technical field of silicon dioxide, and in particular relates to a method for preparing surface-modified silicon dioxide particles. Background technique [0002] With the progress of society and the improvement of people's material life, people's consumption concepts have changed, and consumers have more diversified requirements for products, not only requiring high quality and efficiency of products, but also requiring them to have a certain beauty. Silica colored particles have high dyeing rate, stable coloring, non-toxic and pollution-free, stable chemical and physical properties, and are important additives for daily chemicals such as toothpaste. By adding silica particles of different colors, different colors and appearances can be given to the product, and the ornamental value of the product can be enhanced. In addition, because it has a certain hardness and good cleaning performance, it can play a synergistic effect...

AI Technical Summary

Problems solved by technology

But the suspension time of silicon dioxide of this invention is still unsatisfactory, adopts two-step method reaction, and process is complicated; And use PEG and sodium dodecylsulfonate as modifying agent, consumption is large, and raw material cost is high; One of reaction raw material is Sulfuric acid, with a large amount, not only easily corrodes the reaction equipment, but also produces a large amount of sulfate, which causes great environmental pollution