The working principle of dispersible polymer powder in cement mortar

In order to ensure that the emulsion formed by the redispersion of the polymer latex powder has similar properties to the initial emulsion, a certain amount of protective colloid or surfactant should be added during the emulsion polymerization process to make the redispersible latex powder have stronger properties. Hydrophilicity and sensitivity to alkali can be better re-dispersed into emulsion when in contact with water. Only with good re-dispersibility can latex powder exert its best effect on improving the performance of cement mortar.

During the hardening process of cement, many cavities are generated inside, and moisture can easily accumulate inside these cavities. As the cement solidifies and dries, these cavities become the weakest parts of the cement matrix. When the redispersible latex powder is added, the “self-lubricating effect” makes the latex powder redispersed in the whole mortar by itself. It has good redispersibility in water so that it quickly disperses and forms an emulsion, which fills the empty space occupied by water. cavity. As the drying process progresses, the emulsion is dehydrated again to form a polymer film, which is continuously distributed around the cavity created by the cement curing. These continuous polymer films attached to the hole wall can effectively absorb the stress from the outside, so that the comprehensive performance of the mortar can be improved. At present, the dispersible polymer latex powder is mainly used in building tiles, exterior wall insulation and finishing systems, binders for gypsum-based products and mineral-based finishing mortars, self-leveling floor leveling layers, waterproof mortars, repair mortars and concrete. Repair mortar, wall plastering materials and cement-based powder coatings.