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Nitrile o-rings are made from a copolymer that chemically is termed as that of acrylonitrile and butadiene. The content in sealing products as in o-rings have a varying content of acrylonitrile of between 18 to 50 percent. The ability of the formulation to withstand the aggressive attack of hydrocarbon fuels goes up with the corresponding increase of nitrile content. This benefit of resistance to chemical attack however, is achieved with the sacrifice of flexibility as temperature of the operating environment decreases markedly. 

The capability of nitrile to resist chemical attack from petroleum based solvents and also the benefits of this compound to perform at extreme temperatures of -35 degrees celsius to +120 degree celsius has made it the most popular and extensively used compound for o-rings and sealing applications over a wide span of industries. Military specifications not uncommonly demands the use of nitrile compound for sealing applications in the form of nbr o-ring and sealing gaskets for their applications in fuel and oil realted sealing uses.

Resistance to low temperature is often at the opposite end of the spectrum when it comes to high temperature demands. In comparison with other available elastomeric sealing compounds, it is recognised that nitrile is superior in terms of wear resistance, compression set and abrasion. On the downside, the ability of nitrile to withstand prolong exposure to weather, sunlight and ozone is not good. As such, nitrile material should be kept away from equipment that generate ozone or even near electric motors. Direct exposure to sunlight should be avoided. This disadvantage however, can be effectively addresses through compounding with the right formulation. In pneumatics and hydraulic sealing applications, the use of nitrile or NBR is standard practice. The media that nitrile is able to effectively resist include vegetable oils, fats and oil-based hydraulic fluids. Included are also flame retardant fluids, water, air and grease. Fluids that at mineral-oil based require special low temperature compounds in the formulation. A more specific use of the nitrile material can be created from the process of hydrogenation, through pvc blending or also from the addition of carboxylic acid resulting in a compound that can withstand certain chemical or physical demands.

Nitrile rubber is used extensive and the products that are commonly manufactured from this compound include non-latex gloves, belts for use in automotive transmission, varying types of hoses, sealing products as in seal gaskets and o-rings, synthetic leather and more. In the adhesive manufacturing industry, NBR latex is commonly the material used in its preparation. Minute deviation in the composition of the chemical structure of polymers that are meant for ingestion can significantly have an effect on the body. However, in the case of NBR, such deviation or minor inconsistencies do not alter the properties of nitrile. The manufacturing of NBR as a production process is not exceedingly complicated. The level of difficulty in its production is not unlike that of the manufacturing of most rubber products and the equipment in the production is readily available. NBR is also available in a different version known as hydrogenated nitrile rubber. HNBR is widely adopted as the compound for the production of sealing products used air-conditioning systems for the automotive manufacturing industry.

The use of o-rings in general spans a wide range of industries and material for the manufacturing of sealing compounds are available in various grades that include FFKM perfluoroelastomers, viton FKM, epdm, silicone and more. The selection of the right material and the design of the seal is vital to the success of the sealing process. It is an engineering decision based upon design factors that take into consideration temperature requirements, the type of chemical media that the seals will come into contact with, the expected wear and abrasion that the seal is subjected to, as well as the dynamic and transverse forces that are push the performance of the o-rings and seals to the uppermost limits of their design limitations.