Effect of redispersible emulsion powder in mortar

Release time:




Latex powder

The role of redispersible emulsion powder in mortar is controlled by the two processes of cement hydration and polymer film formation. The composite system of cement hydration and polymer film formation is completed by 4 steps:

(1) the redispersible emulsion powder and cement mortar mixing, evenly dispersed in the system;
(2) polymer particles are deposited on the surface of the cement hydration product gel/unhydrated cement particle mixture;
(3) The polymer particles form a continuous and tight accumulation layer;
(4) In the process of cement hydration, the tightly packed polymer particles are gathered into a continuous film, and the hydration products are bonded together to form a complete network structure.

The dispersed emulsion of redispersible latex powder can form a continuous film (polymer network) insoluble in water after drying. This polymer network with low elastic modulus can improve the performance of cement. At the same time, some polar groups in polymer molecules react with cement hydration products, forming special bridge bonds, improving the physical structure of cement hydration products, alleviating and reducing the generation of cracks. After adding redispersible emulsion powder, the initial hydration rate of cement slows down, and the polymer membrane can partially or completely wrap the cement particles, so that the cement can be fully hydrated and its various properties can be improved.

Key words:

Latex powder