Redispersible emulsion powder is mainly applied for the dry cement mortar of the construction industry, and is the important additive of dry cement mortar.
Redispersible emulsion powder has obvious functions in the dry cement mortar. It can improve the bonding strength and bonding force, the elastic bending strength and rupture strength of the materials. It also can improve the freezeproof property, weathering resistance, durability and wear resistance of the materials. As well as intensify the hydrophobicity and reduce the water absorption, improve the construction characteristic and reduce the contraction ratio of materials. The powder can efficiently prevent cracking.
Improvement of the bonding strength and bonding force
It is quite necessary to add redispersible emulsion powder to the products of dry cement mortar. It can obviously improve the bonding strength and bonding force of materials, as it is because the matrix hole and capillary penetration of the polymer particle to cements form into fine bonding strength after hydrating of the cements. Furthermore, due to the fine bonding force of polymer resin, the powder has better effects on improving the bonding force of dry cement mortar to the basis materials, especially improving the bad bonding property of the inorganic bonder such as cement to the organic materials like woods, fiber, PVC and EPS.
Improvement of the counter bending and tensile property
In the rigid structures after hydrating of the cement mortar, the film elasticity and tenacity of the polymer has the similar function of the mobile joint between the cement mortar particles and particles, then it can bear high distortion load and reduce the stress, as well as improve the tension and resistance to bending.
Improvement of the impact resistance
Redispersible emulsion powder is the thermoplastic resin. The soft film covered on the surface of the mortar particles can absorb outside force impact that is tensile without damage, so as to improve the impact resistance of mortar.
Improvement of the hydrophobicity and reduction of the water absorption
Addition of the redispersible emulsion powder can improve the microscopic structure of the cement mortar. The polymer forms into the irreversible network during the cement hydrating process. Capillary in the close cement gelation can hold up the water absorption and water penetration, so as to improve the penetration resistance capability.
Improvement of the wear resistance and durability
Addition of the redispersible emulsion powder can intensify the dense grade between the cement mortar particles and polymer film. Strengthening of the bonding force correspondingly improves the shearing stress-bearing capacity of the mortar, reduces the wear rate, improves the wear resistance, and prolongs the service life of the mortar.
Improvement of the freeze thawing stability and efficient prevention of the cracking of materials
The plasticity function possessed by the thermoplastic resin of redispersible emulsion powder can overcome the flatulence damage for cement mortar materials brought by temperature difference changes. It can overcome the defects of dry shrinkage and distortion of single cement mortar that is easy to be cracked, and make the material flexible, so as to improve the long stability of materials.
Kinds of the dry cement mortar are various, there are several main kinds applied broadly in current construction project: