Due to the inevitable generation of bubbles during the mixing and construction of flowable mortar such as self leveling and grouting materials, dry powder defoamers are needed to eliminate them.

Reasons for foaming of flowable mortar:

1.The fluidity mortar contains many kinds of active additives, which is easy to cause foam;

2.When flowing mortar is applied, mixing and mechanical vibration cause air to enter and produce foam;

3.When used, water must be mixed for use. In addition, air can easily lead to foam.

What problems may occur with flowable mortar if defoamers are used improperly?

1.The bubbles generated by the self leveling slurry are eliminated too slowly and remain until they harden, forming pinholes. Some may even form honeycomb like surfaces, seriously affecting surface hardness;

2.After the mortar dries and hardens, deep or shallow spots may appear on the surface, directly affecting the appearance. The formation of oily spots is mainly due to poor compatibility between defoamers and the system, resulting in the precipitation of oily components contained within the system;

3.The flowability of mobile mortar is closely related to the fineness and gradation of bone and filler, the type and dosage of water reducing agent, and the performance of stabilizer, and is also affected to some extent by defoamers. The presence of more bubbles is not conducive to the uniform dispersion of self leveling slurry particles, and the addition of defoamers can improve flowability;

4.The presence of bubbles can affect the compactness of the system, resulting in a certain loss of flexural and compressive strength.

What is the defoaming principle of dry powder defoamer?

1.The main components of defoamers are surfactants and organosilicon compounds. These ingredients can reduce surface tension and eliminate foam. When the defoamer is added to the flowing mortar, it will form a film on the surface of the mortar, which can reduce the tension of the mortar surface, make the liquid film of foam thin, and reduce the stability of foam. As time goes on, these foam will gradually burst, so as to achieve the purpose of defoaming.

2.In addition to reducing surface tension and eliminating foam, defoamers can also improve the workability of mortar. Since defoamer can eliminate foam, the air content in mortar is reduced, thus improving the fluidity of mortar. At the same time, defoamers can also improve the compactness of mortar, making it denser and less prone to porosity and cracking. These factors all contribute to the improvement of the construction quality and surface quality of mortar.