Method of preparing silicon dioxide delustrant by large pore volume gel

Abstract

The invention relates to a preparation method of a silicon dioxide flatting agent used for coating flatting with a large pore volume gelatin method, which comprises the following steps of: adding a sodium silicate water solution in a reaction kettle; at the temperature of 26 DEG C and under stirring, adding 30% sulphuric acid until forming gelatin in the kettle; then stirring for 15min, raising the temperature to 50 DEG C and continually adding the sulphuric acid until pH value being up to 3; when no gelatin block by stirring, slowly adding 30% sodium hydroxide into the reaction kettle, regulating the pH value to be 5-6, and then regulating the pH value to be 9-10 by using ammonia water; and raising the temperature to 98 DEG C, ageing for 1 hour, adding water for cooling to the temperature of 75 DEG C, filtration washing, slurrying, sponging drying and crashing classifying to obtain the finished product. The product has the characteristics of large pore volume, large specific surface area, high purity, moderate DBP absorption value, good dispersion performance, high transparency and the like as well as the advantages of reasonable technology and high production efficiency. The product can be added with wax for carrying out surface treatment, thus leading the surface paint film of the coating to be smooth, and improving scratch resistance and precipitate resistance.

Description

technical field [0001] The invention belongs to the preparation technology of powder materials, and in particular relates to a preparation method of a large-pore-volume gel method silica matting agent used for coating matting. Background technique [0002] Matting is an important means for controlling the gloss of decorative coatings. Different objects to be coated have different requirements for the gloss performance of the coated surface in addition to the protection and color requirements due to their different use purposes and environments. Soft light is required, military equipment and facilities are for concealment, confidentiality and security purposes, and some instrument components have special requirements for light performance. The surface coating is semi-gloss or even dull, which requires filling in the coating. Add matting agent. [0003] There are many types of matting agents, such as light calcium carbonate talcum powder and other functional pigments. This ty...

AI Technical Summary

Problems solved by technology

The advantages of this method are high oil absorption value, relatively simple process conditions, and low cost. The disadvantages are that the structure is poor, the structure is easily destroyed under high shear, the specific surface area is small, the pore volume ratio is small, the pore size distribution is wide, and the transparency is poor.