Benefits of SBR Emulsion Polymers vs Other Latex Systems

Introduction

SBR emulsion provides a unique balance of adhesion and flexibility in construction and coating applications. Other latex systems are also common, so we need to know the main difference. This article will explain the key benefits of SBR latex and compare it with acrylic, styrene acrylic, VAE, and PU systems.

Molecular Structure of SBR Determines Performance

SBR is the short name for Styrene Butadiene Rubber. In this article, we refer to the emulsion form of SBR, which can also be abbreviated as E-SBR. E-SBR is a synthetic latex polymer of styrene and butadiene. It combines the advantages of these two monomers by emulsion polymerization.

Styrene segments can provide hardness, strength and abrasion resistance. Butadiene segments offer flexibility and crack resistance. The ratio of styrene to butadiene determines SBR latex properties.

With this molecular structure, SBR latex can perform well under different stress, temperature and water conditions.

Key Benefits of SBR Emulsion Polymers

SBR emulsion polymer is one of the most widely used polymer systems for cement modification. It is mainly used for construction applications with strength and durability needs. You can find the following benefits and differences when compared to other latex systems. 

Excellent Adhesion to Cement-Based Materials

The primary benefit of SBR emulsion polymer is excellent adhesion. It can provide strong bonding to cementitious substrates.

In mortar or concrete systems, the SBR bonding agent will form a continuous film after water evaporation. This polymer film can improve the interface bonding between cement hydration products and aggregates. With strong adhesion, SBR can help you reduce common problems like debonding, hollow, interface failure, and surface peeling.

As you know, the tensile bond strength of conventional cement mortar without polymer modification can not exceed 0.5 MPa. But with SBR modification, it can reach above 1.0 MPa.

Improved Flexibility and Crack Resistance

Cement materials are naturally rigid and brittle and lack flexibility. Internal stress from shrinkage, temperature change or movement will cause cracks.

By introducing an elastic polymer phase into the cement matrix, SBR polymer can improve flexibility. The flexibility of SBR mainly depends on the solids content and Tg (Glass transition temperature). You can choose a lower Tg SBR if you need better elongation and crack-bridging ability.

Enhanced Water Resistance and Durability

You can benefit from the water resistance of Styrene Butadiene Rubber Emulsion in construction applications.

After film formation, SBR polymer creates a hydrophobic network inside the cement structure. The network can reduce capillary water absorption and improve resistance against moisture penetration.

SBR chemical for waterproofing can help improve water impermeability and freeze-thaw resistance.

In SBR-modified cement systems, the water absorption can be reduced by 30%–70% (depending on formulation design).

Better Abrasion Resistance

In industrial floors and repair materials, abrasion resistance is an essential performance requirement.

Styrene Butadiene Rubber has similar properties to natural rubber, with good resistance against repeated impact and surface stress. Mortar modified with SBR generally shows better resistance to mechanical damage than traditional cement mortar.

SBR Emulsion Polymers vs Other Latex Systems

Other latex systems such as acrylic latex, styrene acrylic emulsion, VAE latex, and PU dispersion have their own advantages. No single polymer is all-purpose; you can understand and choose them better when you compare them comprehensively.

SBR Latex vs Acrylic Emulsion

The most prominent properties of SBR latex polymer are flexible adhesion and durability in cement modification.

Acrylic emulsion (pure acrylic emulsion) is brilliant for its UV resistance and color retention. The structure of acrylic latex can ensure stability against wind and sun exposure. It can prevent yellowing and chalking, making it ideal for exterior wall coatings. However, if you use it to modify pure cement, it can not provide balanced flexibility and adhesion like SBR.

For the main property differences between these two latexes, you can refer to the following table for a clear understanding.

SBR vs Styrene Acrylic Emulsion

As we mentioned, SBR latex has superiority in applications where flexibility and cement compatibility are priorities.

Styrene acrylic emulsion combines acrylic (weather resistance) with styrene (hardness/water resistance). The film it forms is stiffer than SBR emulsion and shows excellent water and alkali resistance. But styrene acrylic emulsion does not offer the same flexibility as SBR.

Hence, styrene acrylic emulsion is more commonly used in coatings. You can get a quick comparison of the results from the table below.

SBR vs VAE Emulsion

VAE (Vinyl Acetate Ethylene) emulsion is another important polymer system. The core advantage of VAE is redispersibility. So VAE is often processed into a powder form of RDP for applications in dry-mix mortars. It can rapidly revert to an emulsion state after adding water and offers excellent initial adhesion and workability.

Compared with VAE, SBR emulsion generally provides stronger water resistance and flexibility in liquid systems.

SBR vs Polyurethane (PU) Dispersion

Polyurethane(PU) dispersion is one of the top-tier among water-based polymer systems. It can provide outstanding elasticity and chemical resistance. But the price of PU dispersion is usually higher than that of SBR latex.

You can get different benefits from PU dispersion and SBR latex properties:

Performance Comparison Matrix of Major Latex Systems

Now we have compiled the key performance characteristics of all the emulsions into a single table. You can get a very quick and clear overview of SBR emulsion and other common latex systems.

Choosing the Right Latex System for Construction Applications

By comparing their performance, you can find each latex system’s advantageous areas. If you need to choose the right emulsion polymer for construction and coating applications, you can refer to the recommendations below.

Choose SBR Emulsion Polymer for these applications:

• Cement Waterproof Coating
• Concrete Repair Mortar
• Industrial Flooring
• Cement-Based Adhesive Mortar

Choose Acrylic / Styrene Acrylic Emulsion for these applications:

• Exterior Wall Coatings
• Stone Paint and Textured Coatings
• Decorative Wall Coatings and Latex Paints

Choose PU Dispersion (PUD) for these applications:

• High-Performance Protective Coatings
• Leather Coatings
• Other high-end applications

Choose RDP/VAE for these applications:

• Dry Mix Mortar Systems

Practical Use of Different Emulsion Polymers

In practical formulation, the best latex system depends on the application priority. However, these different emulsions are often mixed together for Polymer Blending. By complementary application, you can get optimal performance at a lower cost.

For instance, you can refer to the following applications:

By blending different emulsions, you can get balanced performance and cost. But you should pay close attention to the compatibility, mixing method, and pH conditions.

Final Thought

SBR and other emulsion polymers have their own advantages. You can choose and mix them based on your application requirements. Celotech Ruico manufactures high-quality SBR latex, acrylic emulsions, and other latex systems. Together with our parent company Celotech, we can custom-blend formulations to help you optimize performance and cost.

FAQ

What’s the Dosage Difference Between SBR and VAE?

In liquid systems, SBR dosage is usually higher. The dosage of VAE also depends on different applications.

Can SBR Latex Replace Acrylic Emulsion in Waterproof Coatings?

SBR latex has good water resistance for waterproof coatings, and acrylic emulsion also has film-forming waterproofing capability. It depends on the coating system.

What Is The Difference Between SBR Latex And SBR Rubber?

SBR latex is a water-based polymer dispersion, while SBR rubber is a solid elastomer material.

How To Test SBR Latex Compatibility With Cement?

You should test the setting time, adhesion, water resistance and mechanical strength.

Can SBR Latex Be Used In Tile Adhesive?

Yes, SBR latex can be used in tile adhesive because of its adhesion and flexibility.

When to Choose Styrene Acrylic Instead of Pure Acrylic Emulsion?

If you need a better balance of hardness and water resistance, you can choose styrene acrylic emulsion.