When using dry powder mortar equipment, some additives are often added, because it can better realize uniform mixing of materials. What additives are generally used when using?
The first is barite (BaSO4). The technical requirement of this additive is that the purity should be more than 95% and the fineness of 4900 mesh, but the addition amount is generally 5 ~ 15%. Its main function is to change the crystal form of hydrated calcium aluminate, prevent the regression of the later strength of calcium aluminate, and use it together with silica fume and CaCO3 to improve the strength of aluminate cement and stabilize the later strength
The second is sodium dihydrogen phosphate. Phosphorus compounds hinder the hardening and hydration speed of cement and achieve the function of retarding setting. It is more suitable in cement retarding, such as sodium polyacrylate and osmotic crystallization waterproof. The technical requirements for S type white powder are usually 0.05 to 0.15% added, and its main functions include thickening, suspension, dispersion, stabilization, etc., which is more suitable for thickening putty, two-component putty, emulsion and so on.
The third is a kind of sodium fluosilicate. The main functions of this additive are sodium fatty sulfonate, acid resistant mastic air entraining agent and sodium sulfate. Micro bubbles are introduced into the mortar through physical action to reduce the density of the mortar and have better workability. The use proportion is 0.01% – 0.06%.
