NBR vs. Nitrile Rubber

Attribute	NBR	Nitrile Rubber
Chemical Name	Acrylonitrile Butadiene Rubber	Nitrile Rubber
Common Name	NBR	Nitrile Rubber
Temperature Range	-40°C to 120°C	-40°C to 120°C
Resistance to Oil	Excellent	Excellent
Resistance to Chemicals	Good	Good
Applications	Automotive seals, gaskets, hoses	Automotive seals, gaskets, hoses

Introduction

When it comes to rubber materials, NBR (acrylonitrile butadiene rubber) and nitrile rubber are two commonly used options in various industries. While they may sound similar, there are key differences between the two that make them suitable for different applications. In this article, we will compare the attributes of NBR and nitrile rubber to help you understand their unique characteristics.

Chemical Composition

NBR is a type of synthetic rubber that is made from a copolymer of acrylonitrile and butadiene. The percentage of acrylonitrile in NBR can vary, typically ranging from 18% to 50%. On the other hand, nitrile rubber is a general term used to describe any rubber that has a high acrylonitrile content, usually above 50%. This means that NBR is a specific type of nitrile rubber with a lower acrylonitrile content compared to other nitrile rubbers.

Physical Properties

One of the key differences between NBR and nitrile rubber lies in their physical properties. NBR is known for its excellent resistance to oil, fuel, and chemicals, making it a popular choice for applications where exposure to these substances is common. Nitrile rubber, on the other hand, has a higher acrylonitrile content, which gives it superior resistance to oil and fuel compared to NBR. However, nitrile rubber may not perform as well as NBR in applications where chemical resistance is crucial.

Temperature Resistance

Both NBR and nitrile rubber have good temperature resistance, with the ability to withstand temperatures ranging from -40°C to 120°C. However, NBR tends to have better heat resistance compared to nitrile rubber, making it suitable for applications where high temperatures are a concern. Nitrile rubber, on the other hand, may become brittle at low temperatures, so it is important to consider the temperature range of the application when choosing between NBR and nitrile rubber.

Compression Set

Compression set refers to the ability of a rubber material to return to its original shape after being compressed. NBR typically has a lower compression set compared to nitrile rubber, which means it can maintain its shape and sealing properties over a longer period of time. Nitrile rubber, on the other hand, may experience more permanent deformation when subjected to compression, leading to potential leaks or failures in sealing applications.

Applications

Due to their unique properties, NBR and nitrile rubber are used in a wide range of applications across various industries. NBR is commonly used in automotive seals, gaskets, and hoses due to its excellent oil and fuel resistance. Nitrile rubber, on the other hand, is often used in O-rings, seals, and gaskets where superior oil resistance is required. Both materials are also used in the manufacturing of gloves, footwear, and other consumer products.

Cost

When it comes to cost, NBR is generally more expensive than nitrile rubber due to its superior chemical resistance and physical properties. While nitrile rubber may be a more cost-effective option for some applications, the choice between NBR and nitrile rubber ultimately depends on the specific requirements of the application and the desired performance characteristics. It is important to consider the long-term benefits of each material when making a decision based on cost.

Conclusion

In conclusion, NBR and nitrile rubber are two versatile rubber materials that offer unique properties for a wide range of applications. While NBR is known for its excellent oil and chemical resistance, nitrile rubber excels in applications where superior oil resistance is required. By understanding the differences between NBR and nitrile rubber, you can make an informed decision when choosing the right material for your specific application.