NBR vs. Viton

Attribute	NBR	Viton
Chemical Resistance	Good	Excellent
Temperature Range	-40°C to 120°C	-20°C to 250°C
Oil Resistance	Good	Excellent
Abrasion Resistance	Good	Excellent
Compression Set	Medium	Low
Tensile Strength	High	Very High
Elongation at Break	Medium	High

Introduction

When it comes to choosing the right material for various applications, it is essential to consider the specific attributes and characteristics of each option. In the world of rubber materials, NBR (Nitrile Butadiene Rubber) and Viton (Fluoroelastomer) are two popular choices. Both NBR and Viton offer unique properties that make them suitable for different applications. In this article, we will compare the attributes of NBR and Viton to help you make an informed decision based on your specific requirements.

Chemical Resistance

Chemical resistance is a crucial factor to consider when selecting a rubber material. NBR exhibits excellent resistance to oils, fuels, and many chemicals, making it a preferred choice for applications involving contact with petroleum-based fluids. On the other hand, Viton offers superior resistance to a broader range of chemicals, including acids, solvents, and even some highly corrosive substances. This makes Viton a suitable option for applications where exposure to aggressive chemicals is expected.

Temperature Range

Another important attribute to consider is the temperature range in which the rubber material can perform effectively. NBR has a relatively lower temperature resistance compared to Viton. It can typically withstand temperatures ranging from -40°C to 120°C (-40°F to 248°F). In contrast, Viton exhibits excellent high-temperature resistance, withstanding temperatures from -20°C to 250°C (-4°F to 482°F). This makes Viton a preferred choice for applications that involve extreme temperature conditions.

Compression Set

Compression set refers to the ability of a rubber material to recover its original shape after being compressed. NBR has good compression set resistance, allowing it to maintain its shape and sealing properties over time. However, Viton offers superior compression set resistance compared to NBR, making it an ideal choice for applications where long-term sealing performance is critical.

Physical Properties

When it comes to physical properties, both NBR and Viton have their own advantages. NBR has excellent tensile strength and tear resistance, making it suitable for applications that require durability and resistance to mechanical stress. Viton, on the other hand, exhibits superior resistance to aging, weathering, and ozone, making it a preferred choice for outdoor applications or those exposed to harsh environmental conditions.

Cost

Cost is often a significant factor in material selection. NBR is generally more cost-effective compared to Viton. This makes NBR a popular choice for applications where budget constraints are a concern. However, it is important to consider the specific requirements of your application and weigh the cost against the desired performance and longevity of the material.

Applications

Both NBR and Viton find applications in various industries due to their unique attributes. NBR is commonly used in automotive seals, gaskets, hoses, and O-rings, thanks to its excellent resistance to oils and fuels. It is also widely used in hydraulic systems, fuel systems, and other applications involving contact with petroleum-based fluids. Viton, on the other hand, is often found in chemical processing, aerospace, automotive, and oil and gas industries. Its superior chemical resistance and high-temperature capabilities make it suitable for applications such as seals, gaskets, O-rings, and other components exposed to aggressive chemicals or extreme temperatures.

Conclusion

Choosing between NBR and Viton depends on the specific requirements of your application. NBR offers excellent resistance to oils and fuels, making it a cost-effective choice for applications involving petroleum-based fluids. On the other hand, Viton provides superior chemical resistance, high-temperature capabilities, and compression set resistance, making it suitable for applications involving aggressive chemicals, extreme temperatures, and long-term sealing performance. Consider the chemical compatibility, temperature range, compression set requirements, physical properties, and cost to make an informed decision. Both NBR and Viton have their own strengths, and selecting the right material will ensure optimal performance and longevity in your application.