Nitrile vs. Viton

Attribute	Nitrile	Viton
Chemical Composition	Nitrile rubber is a synthetic rubber copolymer of acrylonitrile (ACN) and butadiene.	Viton is a fluoroelastomer made from a combination of vinylidene fluoride (VDF) and hexafluoropropylene (HFP).
Temperature Range	Nitrile has a temperature range of -40°C to +120°C (-40°F to +248°F).	Viton has a temperature range of -20°C to +200°C (-4°F to +392°F).
Chemical Resistance	Nitrile offers good resistance to oils, fuels, and many chemicals.	Viton provides excellent resistance to a wide range of chemicals, including acids, fuels, and oils.
Physical Properties	Nitrile has good tensile strength, tear resistance, and abrasion resistance.	Viton exhibits excellent mechanical properties, including high tensile strength, good tear resistance, and low compression set.
Applications	Nitrile is commonly used in automotive seals, gaskets, hoses, and O-rings.	Viton is often used in applications requiring resistance to high temperatures and aggressive chemicals, such as aerospace, automotive, and chemical industries.

Introduction

Nitrile and Viton are two popular materials used in various industries for their unique properties and applications. While both are elastomers, they differ in terms of chemical composition, physical properties, and performance characteristics. In this article, we will explore and compare the attributes of Nitrile and Viton, shedding light on their strengths and weaknesses.

Chemical Composition

Nitrile, also known as Nitrile Butadiene Rubber (NBR), is a synthetic rubber copolymer made from acrylonitrile and butadiene. It offers excellent resistance to oils, fuels, and chemicals, making it a popular choice for applications involving contact with petroleum-based substances. On the other hand, Viton, a brand of fluoroelastomer, is composed of vinylidene fluoride and hexafluoropropylene. Viton exhibits exceptional resistance to high temperatures, chemicals, and solvents, making it suitable for demanding environments.

Physical Properties

When it comes to physical properties, Nitrile and Viton have distinct characteristics. Nitrile has good tensile strength, tear resistance, and abrasion resistance, making it durable and long-lasting. It also maintains its flexibility over a wide temperature range, typically from -40°C to 108°C (-40°F to 226°F). Viton, on the other hand, boasts excellent heat resistance, withstanding temperatures up to 204°C (400°F) and even higher for short durations. It also exhibits low compression set, meaning it can maintain its shape and sealing properties under pressure.

Applications

Due to their unique attributes, Nitrile and Viton find applications in various industries. Nitrile is commonly used in automotive seals, gaskets, hoses, and O-rings due to its resistance to oils and fuels. It is also utilized in the manufacturing of gloves, as it provides excellent protection against chemicals and punctures. Viton, on the other hand, is widely employed in the aerospace, automotive, and chemical industries. It is used for seals, gaskets, O-rings, and other components that require resistance to high temperatures, aggressive chemicals, and fuels.

Chemical Resistance

Both Nitrile and Viton exhibit impressive chemical resistance, but their performance varies depending on the substances they come into contact with. Nitrile is highly resistant to oils, fuels, and hydrocarbons, making it suitable for applications in the automotive and oil industries. It also provides good resistance to water, alcohols, and some acids. Viton, on the other hand, excels in resisting a broader range of chemicals, including strong acids, solvents, and aggressive fuels. It is often chosen for applications where exposure to harsh chemicals is expected.

Cost

Cost is an important factor to consider when selecting between Nitrile and Viton. Nitrile is generally more cost-effective compared to Viton, making it a popular choice for applications where high chemical resistance or extreme temperature resistance is not required. However, for applications that demand superior performance in harsh environments, Viton's higher cost may be justified by its exceptional properties and durability.

Compatibility with Other Materials

Another aspect to consider is the compatibility of Nitrile and Viton with other materials. Nitrile exhibits good compatibility with various metals, such as steel, aluminum, and brass. It can also be used with certain plastics, including PVC and polyurethane. Viton, on the other hand, may not be compatible with certain materials, such as acetone, ketones, and some esters. It is important to consider the specific application and the materials that will come into contact with the elastomer to ensure compatibility and prevent any adverse reactions.

Conclusion

In conclusion, Nitrile and Viton are two elastomers with distinct attributes and applications. Nitrile offers excellent resistance to oils, fuels, and chemicals, making it suitable for automotive and industrial applications. It also provides good physical properties and maintains flexibility over a wide temperature range. Viton, on the other hand, excels in high-temperature environments and exhibits exceptional resistance to aggressive chemicals and solvents. It finds applications in industries such as aerospace, automotive, and chemical manufacturing. The choice between Nitrile and Viton depends on the specific requirements of the application, including temperature range, chemical exposure, and cost considerations.