Polyacrylate Rubber (ACM）

Nitrile Rubber(NBR)

Nitrile Rubber，also known as NBR or Buna N,is one of the most commonly used sealing elastomers due its resistance to petroleum based fuels and lubricants and its relatively low price.Nitrile elastomers are copolymers of acrylonitrile and butadiene.There are a number of common variations of nitrile compounds.

Acrylonitrile Content

The acrylonitrile(CAN)content of the polymer chains can be varied from 18% to 50%.Lower CAN content gives better low temperature properties but poorer fuels and polar lubricants.Higher CAN content gives poorer low temperature properties but omproved fuels and polar lubricants resistance.Standard NBRs typically have 34% ACN content.

Cure system-Sulfur-Cured vs.Peroxide-Cured

Standard Nitriles are usually sulfur-cured compounds offer better low temperature properties but are more prone to hardening with high temperatures.Peroxide-cured nitriles have better heat resistance and lower compression sets but are more expensive and are more difficult to process.

Other Common Variations

●Nitriles are often internally lubricated to improve ease of installation or reduce friction for dynamic applications

●Nitriles can be for mulated with only”white list”ingredients as specified in 21.CFR 177.2600 for use in applications where the elastomer will be in contact with food or beverages

●Nitriles can be submitted for approval by the National Sanitation Foundation(NSF)for use in drinking water applications.

●Nitriles can also be submitted for approval to Underwriters Laboratories(UL)for use in applications as prescribed in UL157.

●Nitrile rubber can be combined with polyvinyl chloride(PVC)to create fuel,ozone and weathering resistance NBR-PVC blends.

Performs Well In…

●Petroleum based oils＆fuels

●Aliphatic hydrocarbons

●Vegetable oils

●Silicone oils＆greases

●Ethylene glycol

●Dilute acids

●Water to below 100℃(212℉)

General Information

ASTM D1418 Designation

NBR

ISO/DIN1629 Designation

NBR

ASTM D200/SAE J 200 Codes

BF,BG,BK,CH

Standard Color(S)

Black

Hardness Range

40 to 90 Shore A

Relative Cost

Low

Service Temperatures

Standard Low Temperature

—40℃
—40℉

Standard high Temperature

100℃
212℉

Special Compound Low Temperature

—55℃
—67℉

Special Compound High Temperature

135℃
275℉

Doesnt Perform Well In…

●Automotive brake fluid

●Ketones

●Esters

● Ethers

●Strong acids

●Ozone/weathering/sunlight

●Phosphate ester hydraulic fluids

●Chlorinated hydrocatbons

●Automotive brake fluid