What is the role of redispersible latex powder in gypsum-based self-leveling?

Redispersible latex powder is an important additive that affects the performance of thick-layer gypsum-based self-leveling mortar. The influence of re-dispersible latex powder on the physical and mechanical properties of thick-layer gypsum-based self-leveling mortar is tested, and the redispersible latex powder is revealed through microscopic analysis. The principle of improving the mechanical properties of gypsum-based self-leveling mortar shows that redispersible latex powder plays a huge role in gypsum-based self-leveling.

Redispersible latex powder is a widely used organic binder, which can improve the performance of products when used in gypsum-based building materials. Experiments have found that the initial fluidity of thick-layer gypsum-based self-leveling mortar increases first and then decreases with the increase in the amount of latex powder. The reason is that the latex powder has a certain viscosity in the dissolved water. The suspension ability of the slurry to the filler is improved, which is beneficial to the flow of the slurry; when the amount of latex powder continues to increase, the increase in the viscosity of the slurry leads to an increase in the viscosity of the slurry, and the fluidity shows a downward trend. The amount of latex powder has almost no effect on the 20min fluidity of the mortar.

As an organic binder, the strength of latex powder depends on the evaporation of water in the slurry, and the bond strength is formed by film formation. In the dry state, the water in the gypsum-based self-leveling mortar evaporates, and the latex powder can form a continuous film. Better adhesion, the dry strength of gypsum-based self-leveling mortar increases with the increase in the amount of latex powder.

In the gypsum-based self-leveling mortar without latex powder, there are a large number of rod-shaped and columnar dihydrate gypsum crystals and irregular filler dihydrate gypsum crystals and between dihydrate gypsum crystals and fillers. Pile together to make the gypsum-based self-leveling mortar produce strength, and the gypsum-based self-leveling mortar mixed with redispersible latex powder, the latex powder forms a filamentary connection in the gypsum-based self-leveling mortar, and the dihydrate gypsum crystals and fillers, crystals An organic bridge is formed between the crystal and the dihydrate gypsum crystal, and an organic film is formed on the dihydrate gypsum crystal to wrap and connect the overlapping parts between the dihydrate gypsum crystals, thereby increasing the cohesion and cohesion of the gypsum-based self-leveling mortar and improving the The strength of gypsum-based self-leveling mortar The latex powder has film-forming properties in the mortar, which can improve the cohesion and bonding strength of the dry mortar. The formation of effective bonding between the fillers improves the cohesion between the dihydrate gypsum crystals and the fillers, thereby improving the bond strength of the gypsum-based self-leveling mortar macroscopically.