Redispersible polymer powder (RDP) is a free-flowing powder made by spray drying emulsion, which can be redispersed into a stable polymer emulsion when it comes into contact with water. It is widely used in many industries such as construction, adhesives, and sealing materials, and is an indispensable modified additive in dry-mixed mortar.
1. Performance characteristics of Redispersible polymer powder
1.1. Strong redispersibility
The biggest feature of RDP is that it can be re-emulsified when it comes into contact with water to form a polymer dispersion with uniform particle size and stability. This property enables it to be stored for a long time in a dry powder system. When used, it only needs to add water to restore it to the original emulsion state and maintain its original film-forming properties.
1.2. Excellent bonding
Redispersible polymer powder can penetrate into the micropores on the surface of the substrate and form a mechanical lock with the substrate. At the same time, through the polymer film formed after its film formation, it improves the cohesion and bonding strength of the material, which is particularly suitable for various interface treatment and bonding construction scenarios.
1.3. Flexibility and crack resistance
Due to the good flexibility of polymer film, Redispersible polymer powder can significantly improve the deformation resistance of mortar and coating systems, reduce cracks caused by shrinkage or temperature change, and improve the overall stability of the system.
1.4. Strong water resistance and alkali resistance
After adding RDP, it can still maintain good bonding performance and durability in a wet or alkaline environment, suitable for alkaline systems such as cement-based materials, and enhances anti-seepage and moisture resistance.
1.5. Improved construction performance
It can improve the water retention, workability, and delay the opening time of dry-mixed mortar, making construction more convenient, helping to reduce construction difficulty and improve construction efficiency.
2. Main application areas of Redispersible polymer powder
2.1. Tile adhesive and tile backing adhesive
Adding RDP to tile adhesive can significantly improve the bonding strength of the product, especially for low water absorption tiles (such as vitrified tiles) or large-sized tiles. Its flexibility can also adapt to wall deformation and prevent tiles from hollowing or falling off.
2.2. External Insulation System (EIFS)
RDP improves the bonding strength between insulation boards such as EPS and XPS in insulation board adhesives and plastering mortars, while enhancing crack resistance and preventing cracking caused by temperature differences.
2.3. Self-leveling floor
RDP enhances the bonding and wear resistance of cement-based self-leveling mortar, making the floor smoother and firmer, and to a certain extent improving crack resistance and water resistance.
2.4. Waterproof mortar and flexible anti-cracking mortar
Its good film-forming property and flexibility can significantly improve the waterproof performance of mortar, and it is used for kitchen and bathroom waterproofing, basement anti-seepage and other projects. Composited with other inorganic materials, it can be made into a flexible waterproof layer.
2.5. Internal and external wall putty powder
Adding RDP to putty can improve the adhesion and anti-powdering ability of putty, while improving the workability and surface finish, and reducing the delamination and cracking problems caused by loose base.
2.6. Repair mortar and grouting materials
RDP improves the plasticity and adhesion of repair materials, and is suitable for occasions such as concrete defect repair and pipeline plugging, and improves its durability and ability to adapt to changes in the base.
2.7. Interface agent and wall and floor leveling materials
The use of RDP in the interface agent can enhance the bonding strength between the new and old bases, so that the leveling layer and plaster layer are firmly combined with the base to prevent peeling.
As an organic polymer additive with excellent performance, Redispersible polymer powder has become an indispensable and important component in modern building dry-mixed mortar. It greatly improves the comprehensive performance of various building materials by improving the flexibility, adhesion, construction and durability of the material. With the improvement of green building and energy-saving and environmental protection requirements, the application field of RDP will be more extensive, and its technology and varieties will continue to be optimized and innovated. In the future, Redispersible polymer powder will play a more important role in promoting the upgrading of building materials and the innovation of construction technology.
Post time: Jun-24-2025