Redispersible polymer powder (RDP) is an important polymer additive used to enhance the performance of cement-based, gypsum-based, lime-based and lime-mortar-based materials. RDP improves the comprehensive performance of these materials through its bonding performance, reinforcement, crack resistance, water resistance, etc., and is widely used in building materials.
Main types of RDP
RDP types are mainly classified according to the type of substrate they are composed of, the application field and functional characteristics. Common RDPs include the following:
Ethylene-vinyl acetate copolymer (EVA) type:
Features: Ethylene-vinyl acetate copolymer is one of the most common types of RDP. It has excellent flexibility and adhesion, and provides good water resistance and weather resistance.
Application: Mainly used in tile adhesives, self-leveling floor materials, exterior wall insulation systems and other fields.
Advantages: It provides good toughness and flexibility, suitable for occasions requiring certain flexibility and adhesion.
Disadvantages: Due to its high ethylene content, its performance may be slightly insufficient in some applications with high strength requirements.
Ethylene-vinyl acetate-vinyl acetate terpolymer (VeoVa/EVA) type:
Features: This type of RDP introduces VeoVa (vinyl ester) on the basis of ethylene and vinyl acetate copolymerization, which improves the water resistance and chemical stability of the material.
Application: Commonly used in exterior wall coatings and gypsum products, etc.
Advantages: It has better water resistance and chemical resistance, suitable for outdoor and chemically harsh applications.
Disadvantages: Compared with traditional EVA type, the cost may be slightly higher.
Styrene-butadiene copolymer (SB) type:
Features: It is mainly composed of styrene and butadiene monomers, and has good bonding properties, flexibility and water resistance.
Application: Commonly used in tile adhesives and flexible putties.
Advantages: Good bonding and flexibility, and also excellent performance in water resistance.
Disadvantages: May age under ultraviolet light.
Vinyl acetate-ethylene copolymer (VAE) type:
Features: It is a copolymer of vinyl acetate and ethylene, with excellent flexibility and water resistance.
Application: It is suitable for tile adhesives, exterior wall insulation systems, gypsum-based self-leveling, etc.
Advantages: It provides good adhesion and water resistance, and has certain chemical resistance.
Disadvantages: The cost is relatively high.
Acrylic copolymer (Acrylic) type:
Features: The main component is acrylic ester, which has excellent adhesion and flexibility.
Application: It is widely used in decorative mortar, tile adhesives, gypsum and other materials.
Advantages: Excellent adhesion and flexibility, and excellent UV resistance.
Disadvantages: Due to the high cost of acrylic materials, the cost of this type of RDP is also high.
Functions and applications of RDP
Improved bonding performance:
RDP plays a bridging role in the material, enhances the adhesion of the adhesive, and improves the bonding between the building material and the substrate.
Application areas include tile adhesives, bonding mortars, etc.
Enhanced flexibility and crack resistance: By adding RDP, the flexibility of the material is significantly improved, which helps prevent the occurrence of cracks.
Commonly used in insulation systems, flexible putty, repair materials, etc.
Improved water resistance and water resistance:
RDP improves the water resistance of the material, allowing it to maintain stable performance in a humid environment.
Applied in waterproof coatings, exterior wall coatings, etc.
Improved construction performance:
RDP can improve the construction performance of dry powder materials, making construction easier and more efficient.
Widely used in self-leveling floor materials, coatings, etc.
Improved durability and weather resistance: Due to the addition of RDP, the durability and weather resistance of the material are greatly improved, and it can withstand the test of harsh environments.
Applied to exterior wall systems, roof coatings, etc.
Considerations for choosing a suitable RDP
Application scenarios:
Choose the appropriate RDP type according to the specific application scenario, for example, outdoor applications require RDP with good weather resistance.
Cost control:
On the premise of ensuring performance, it is necessary to consider the material cost and choose an economical RDP.
Compatibility:
RDP needs to be well compatible with other materials to ensure the stability and performance consistency of the mixture.
Performance requirements:
Choose the appropriate RDP type according to the required properties (such as flexibility, adhesion, water resistance, etc.).
Redispersible latex powder plays an important role in modern building materials, and its various types provide flexible solutions for various construction needs. Choosing the appropriate RDP type can greatly improve the performance of building materials, thereby improving the quality and durability of construction projects.
Post time: Jul-05-2024