Introduction to the application of silica sol in coatings

2024-07-02 17:13 Mike

Silica sol, also known as silicate water glass, is an inorganic polymer polysilicic acid colloidal solution with water as the dispersed phase. It is odorless and tasteless, has a large specific surface area, and the particles themselves are colorless and transparent, which does not affect the properties of the coating. Most of the particles are spherical or single-agglomerated. The diameter of the colloidal particles is usually 5-8NM, which is smaller than the diameter of ordinary emulsions, and the permeability is 0.1-10UM. The penetration effect is very good. As the water evaporates, Si-O bonds are formed, which have strong rigidity and bonding ability. Therefore, it is widely used in coating production.

Cracks, micropores and other defects are prone to occur during the film formation and dehydration process of the coating. Therefore, organic polymers are introduced to make the organic polymers randomly and evenly distributed in the gaps of the Si-O bonded film, thereby improving the toughness, impact resistance and water resistance of the film. Silica sol can be mixed with water-based polymer compounds and polymer emulsions. The modification of emulsions by silica sol is different from that of visual emulsions. Silica sol can be mixed with a variety oforganic polymers, so it can be used in a variety of coating systems, such as sealing primers, elastic coatings, waterproof coatings, low PVC coatings, common interior and exterior wall coatings and non-high gloss water-based coatings wood paints, etc., which can change the performance of the coating andcover up the defects of the coating itself.