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Product Introduction


Oil resistant rubber

■ NBR:

NBR is a copolymer of butadiene with acrylonitrile and was initially used to make products resistant against gasoline or petroleum. It exhibits better resistance against aromatic hydrocarbons than neophytadiene but slightly below that of polysulfides. NBR has good resistance to mineral oils and vegetable oils. However, NBR has lower resistance against oxidizing agents such as acetone, butanone, and other ketones. NBR has good resistance against acids and bases, but not to those that are considered strong oxidants. The excellent heat aging performance of NBR is the main reason why it is considered a better material than natural rubber.

■ Limitation: 

It has no resistance to ozone, sunlight, natural aging and oxidizing agent.

■ Chemical properties:

ASTM D1418 Designation:NBR

ISO 1629 Designation:NBR

ASTM D2000/SAE J200 Type, Class:BF, BG, BK, CH

■ Trade name:


■ KTseal NBR Compound:

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KTseal mixture Hardness Color Description

55 Black General purpose: used by internal lubricating oil.
NB475 75 Black General purpose: used by internal lubricating oil; low compression set; cross-linking agent of peroxide.
NB430 80 Black Used by internal lubricating oil; certified by FDA Food and Drug Administration (excluding cheese/fat foods).
NB442 70 Black Used by internal lubricating oil; low temperature resistance level.
NB431 60 Black Used by internal lubricating oil; gasolineresistance level.
NB418 70 Black Used by internal lubricating oil; ozoneresistance level.
NB447 70 Black Used by internal lubricating oil; high temperatureresistance level.
NB470 70 Black Used by internal lubricating oil; conductive level.
NB433 70 Black SAE J120 flame resistance level.
NB432 75 Black High RPM, wear resistance level.
NB466 65 Black Used by aerospace aircraft.
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※ A=Best  B= Common  C=Poor  D= Not recommended
NBR O-Ring
Common name or commodityNltrlleor Buna N
Chemical nameNltrlleButadi-ene
ASTM D1418 Nomenclature--→NBR
ASTM D2000 SAEJ200→
Type. class    
Material properties
Density (gm/cm3)1.00
Hardness range (Shore A)20-90
Gas permeabilityB-A
Electrical resistanceD-C
Stain resistanceC-B
Mechanical properties
Tensile strength (max psi)3,500
Friction resistanceA
Deflection resistanceB
Tearing resistanceB
Impact resistanceC
Rebound resilienceB
Stress reliefB
Thermal properties
Recommended max. application temperature (℃)100-125
Low-temperature toughnessC
Thermal aging resistanceB
Flame resistanceD
Resistance to following elements
Alkali (dil/conc)B/B
Acid (dil/conc)B/B
Oil, gasoline, keroseneA
Benzene, hydrocarbon waterB
Animal and vegetable oilB
Oxidizing solventD
HALOGEN solventC-B
Synthetic lubricating oilB-A
Hydraulic circulation: 

■ Note

  1. The higher the density, the more rubber material used. For example: although the unit price of neoprene is the same with natural rubber, but it's actually still very expensive.
  2. Sometimes the tensile strength is not important, but unchanged tensile strength during temperature rise means other mechanical properties can also remain unchanged.
  3. There is a wide range of temperature and friction mode for friction resistant application (e.g. scraping and colliding).
  4. High fracture resistance means good durability, and such property is required when physical abuse is expected.
  5. When physical abuse is expected to occur, tearing resistance must be accompanied by fracture resistance.
  6. During strong deformation, only stress-induced crystallization rubber has good durability, and low temperature curvature can also help to improve the impact resistance.
  7. Generally, high deformability means high fatigue resistance under deflection state.
  8. The less the permanent deformation, the better the structural integrity, the more it can maintain its original size.
  9. The better the elasticity, the less the internal heat increase in deflection or dynamic condition.
  10. The better the creep resistance, the longer the service life of products (especially when the product clearance must be kept constant).
  11. Stress relief is necessary for sealing or other frequently stressed products.
  12. For most of vibration buffering devices, good low temperature flexibility is necessary, and the initial swing and subsequent softness are more important.
  13. Oil resistance is the most important surface effect, and deterioration will not occur due to exposure in oil when the oil resistance is poor but volume is large enough.