Redispersible latex powder plays a hardening role in putty powder

The role of redispersible latex powder in putty powder:

Redispersible latex powder in putty powder can reduce the elastic modulus of putty and enhance the matching to the base layer; improve the micropore structure of cement, increase flexibility and crack resistance after adding latex powder; improve powder drop resistance; water repellency or reduce putty layer Water absorption; increase the adhesion of putty to the base wall.

The relationship between the hardness of putty powder and the content of redispersible latex powder:

The weights of redispersible latex powder added to putty powder were 0 kg, 3 kg, and 8 kg respectively. After 7 days of putty curing, the putty with different additions of redispersible latex powder showed different shapes. For putty with 0 kg of latex powder added, the gaps between the inorganic skeletons in the putty are large and numerous;When the amount of latex powder is less than 3 kg, the cured latex powder fills the gap between part of the inorganic skeleton; when the amount of latex powder in the putty exceeds 5 kg, the cured latex powder not only fills part of the inorganic skeleton At the same time, it forms a film in a small range, which strengthens the inorganic skeleton, thereby greatly increasing the viscosity and strength of the putty. When the amount of latex powder added to the putty increases to 8 kg, the latex powder can be seen In a wide range of film formation, the cross-section of the putty is almost entirely a polymer film, which weakens the continuity of the inorganic skeleton, thus reducing the bond strength of the putty.

According to the experimental and practical research data, the optimal amount of latex powder in the putty should be 5-8 kg, and the amount of hydroxypropyl methylcellulose should be 3-5 kg. For different types of putty powder, it can be redispersed The amount of latex powder added is also different.

Effect of redispersible latex powder on hardened putty:

The external wall putty generally uses cement as the inorganic bonding material, and a small amount of ash calcium is added to achieve a synergistic effect. Adding redispersible latex powder can make the surface layer putty provide a good base surface, reduce the amount of paint used, thereby reducing the project cost; adding redispersible latex powder can make the putty have strong adhesion and can adhere to the base wall Above; redispersible latex powder has a certain toughness, which can well buffer the effect of different stretching stresses produced by different base layers, and has good crack resistance; adding redispersible latex powder to putty can have good weather resistance and impermeability , Moisture resistance, long service life; environmental protection, non-toxic, safe; putty powder with rubber powder can be used for material modification, adding redispersible latex powder can make the putty powder have good thixotropy, as long as it is smoothed by simple smoothing A nearly perfect smooth surface can be obtained, which can reduce the loss caused by multiple coatings due to uneven base surface; the redispersible latex powder is elastic, which can make the putty powder resist micro cracks and offset the damage of temperature stress; redispersible latex The addition of powder can make the putty powder maintain good hydrophobicity and play the role of waterproof and seepage.