Application in Coatings

The silica sol particles are fine, and the silica formed during gel separation has high activity. It can form new silicate inorganic polymer compounds with certain inorganic salts and metal oxides, forming a very hard film; The small particles have strong permeability to the substrate, and can penetrate into the interior of the substrate through capillary action. They can react with the alkaline substance Ca (OH) z in the substrate to form calcium silicate, which gives the coating strong adhesion.  

The enhancement of adhesion is the comprehensive effect of the penetration and hardening bonding of silica sol, which is the result of mechanical interlocking and chemical bonding. Therefore, it has a better surface adhesion than general coatings. Silica sol is miscible with organic polymer, allowing the organic polymer to be evenly distributed in the gaps of the silicon oxygen silicon inorganic coating, shielding the remaining hydrophilic groups in the inorganic coating. When the coating is subjected to alternating cold and heat, the shrinkage of the coating is buffered, and the coating has a certain degree of elasticity. The formed coating combines the characteristics of both inorganic and organic coatings, making up for the shortcomings of both.  

After the formation of silica sol film, a network structure of silica oxide is formed, which is not afraid of acid and alkali and improves the performance of the coating film. The composite wall coating prepared with silica sol as the main film-forming material, synthetic lotion (such as styrene acrylic lotion, vinyl acetate resin lotion, etc.) as the auxiliary film-forming material, pigment, filler, and JJH-J addition has unique water resistance, fire resistance, scrub resistance, and pollution resistance. The casting coating prepared by mixing silica sol and refractory powder can effectively prevent the melting of molten steel and the wear of flat plates during the casting of steel ingots. Most high-end latex paints such as Nippon Paint now contain silica sol.

In addition, silica sol is widely used in the preparation of metal surface thermal conductive coatings, water-resistant porcelain like coatings, wall bead steel coatings, energy-saving and anti-corrosion high-temperature ceramic coatings, metal insulation coatings, foam fireproof coatings, etc.