Why is redispersible polymer powder (RDP) so important in construction?

19 Mar.,2024

Redispersible polymer powder is mainly used in: interior and exterior wall putty powder, tile adhesive, tile grouting, interface agent, exterior insulation mortar, self-leveling mortar, repair mortar, decorative mortar, waterproofing mortar, dry mix mortar. In the mortar, the purpose is to improve the brittleness, high elastic modulus and other weaknesses of traditional cement mortar

 

Redispersiblepolymer powder products are water-soluble redispersible powders, which are divided into ethylene/vinyl acetate copolymers, vinyl acetate/ethylene tertiary carbonate copolymers, acrylic acid copolymers, etc. The powder made after spray drying is bonded agent, using polyvinyl alcohol as a protective colloid. This kind of powder can be quickly redispersed into an emulsion after contact with water. Because the redispersible polymer powder has high bonding ability and unique properties, such as water resistance, construction properties and heat insulation, their The scope of application is extremely broad.

I.  Advantages of redispersible polymer powder

1. It does not need to be stored and transported with water, reducing transportation costs;

2. Long storage period, anti-freeze, easy to store;

3. Small packaging size, light weight and easy to use;

4. It can be mixed with hydraulic binders to form synthetic resin-modified premixes. When using, just add water. This not only avoids errors during mixing at the construction site, but also improves the safety of product handling. sex.

II. Uses of redispersible polymer powder

Redispersible polymer powder is mainly used in: interior and exterior wall putty powder, tile adhesive, tile grouting, interface agent, exterior insulation mortar, self-leveling mortar, repair mortar, decorative mortar, waterproofing mortar, dry mix mortar. In the mortar, the purpose is to improve the brittleness, high elastic modulus and other weaknesses of traditional cement mortar, and to give the cement mortar better flexibility and tensile bonding strength to resist and delay the occurrence of cracks in the cement mortar. Since the polymer and mortar form an interpenetrating network structure, a continuous polymer film is formed in the pores, which strengthens the bonding between aggregates and blocks some pores in the mortar. Therefore, the hardened modified mortar has better performance than cement mortar. There is a big improvement.

 

III. The role of redispersible polymer powder in mortar:

1. Improve the compressive strength and flexural strength of mortar.

2. The addition of redispersible polymer powder increases the elongation of the mortar and thereby improves the impact toughness of the mortar. It also gives the mortar good stress dispersion.

3. Improve the bonding performance of mortar. The bonding mechanism relies on the adsorption and diffusion of macromolecules on the sticky surface. At the same time, the redispersible polymer powder has a certain permeability and can fully infiltrate the surface of the base material together with the cellulose ether, so that the surface properties of the base layer are close to those of new plastering, thus improving the adsorption properties greatly increase its performance.

4. Reduce the elastic modulus of mortar, improve deformation ability, and reduce cracking.

5. Improve the wear resistance of mortar. The improvement of wear resistance is mainly due to the presence of a certain amount of rubber on the surface of the mortar. The redispersible polymer powder plays a bonding role. The network structure formed by the redispersible polymer powder can pass through the holes and cracks in the cement mortar. The bonding between the base material and the cement hydration products is improved, thereby improving the wear resistance.

6. Give the mortar excellent alkali resistance.