Redispersible Polymer Powder (RDP) is a free-flowing, white powder obtained by spray-drying polymer emulsions. It is widely used in construction materials, especially in dry-mix mortars, to improve their performance and properties. When mixed with water, RDP can re-emulsify and form a film, providing enhanced adhesion, flexibility, water resistance, and workability to the final product.
Composition
RDP is typically made from:
- Vinyl acetate-ethylene (VAE) copolymers
- Acrylics
- Styrene-butadiene
- Other polymers
These polymers are emulsified in water, spray-dried, and combined with protective colloids (e.g., polyvinyl alcohol) to ensure redispersion in water.
Key Properties
- Redispersibility: RDP can re-emulsify in water, forming a film upon drying.
- Adhesion: Improves bonding strength to various substrates.
- Flexibility: Enhances crack resistance and durability.
- Water Resistance: Reduces water absorption and improves moisture resistance.
- Workability: Improves the application and handling of mortars.
- Cohesion: Enhances internal bonding and mechanical strength.
Applications
RDP is widely used in the construction industry, particularly in:
- Tile Adhesives:
- Improves adhesion, flexibility, and water resistance.
- Exterior Insulation and Finish Systems (EIFS):
- Enhances crack resistance and durability.
- Self-Leveling Flooring Compounds:
- Improves flowability, adhesion, and strength.
- Repair Mortars:
- Provides excellent bonding and durability.
- Waterproofing Membranes:
- Enhances water resistance and flexibility.
- Gypsum-Based Products:
- Improves workability and reduces cracking.
- Cementitious Renders and Plasters:
- Enhances adhesion, flexibility, and water resistance.
Advantages
- Improved Performance: Enhances the mechanical and physical properties of construction materials.
- Ease of Use: Can be easily mixed with dry ingredients.
- Versatility: Compatible with a wide range of building materials.
- Durability: Increases the lifespan of construction products.
- Environmental Benefits: Reduces the need for on-site mixing and waste.
How It Works
- Mixing: RDP is added to dry-mix formulations.
- Redispersion: When water is added, the powder re-emulsifies.
- Film Formation: As the mixture dries, the polymer forms a film that binds the components together.
- Performance Enhancement: The film improves adhesion, flexibility, and other properties.
Storage and Handling
- Store in a cool, dry place.
- Keep the packaging sealed to prevent moisture absorption.
- Avoid direct contact with skin and eyes during handling.
Popular Brands
- VINNAPAS® by Wacker Chemie
- ELOTEX® by Celanese
- ACRONAL® by BASF
- RE5010N by Shandong Xindadi
RDP is a crucial additive in modern construction materials, offering significant improvements in performance and durability. If you need more specific information about its use in a particular application, feel free to ask!
