Polyurethane vs Buna-N (NBR) for O-Rings and Seals

Polyurethane (PU, TPU)

Buna-N (NBR, Nitrile, Buna)

Description
Both materials are well suited for use in the -23 to 66°C range. Buna-N has an advantage in lower temperatures and Buna-N has an advantage in higher temperatures. Marco offers specific compound formulations extending these ranges even futher as can be seen in the following compound comparison chart. When comparing these materials with respect to electrical current resistance, Polyurethane has a slight advantage. The differences in compression set resistence show that Buna-N has a significant advantage. Additionally, Buna-N has a significant advantage when considering wear resistance. Also, Buna-N has a significant advantage when comparing heat stability. Furthermore, Polyurethane has a slight advantage when comparing short term resilience. Finally, both materials are equally Poor when evaluating differences in permeation resilience. Both materials are resistant to common fuels, mineral oils, greases, aliphatic hydrocarbons, silicone oils, hydraulic fluids and water, with Polyurethane having specific resistences to ozone, chlorinated hydrocarbons, aging, weathering and sunlight, oxygen, tear, brake fluids, silicone greases, some petroleum oils and some hydrocarbon fuels. Buna-N has specific resistence to acids, solvents, vegetable oils, diluted alkalies, petroleum oils, ethylene glycol fluids, di-ester lubricants and alcohols.
Compounds
Marco
Compound
Number
DatasheetHardness
(Shore A)
ColorLow TempHigh TempFeatures
Compound: B1000Datasheet: View DatasheetHardness: 70Color: BlackLow Temp:
-30 °F
(-35 °C)
High Temp:
250 °F
(125 °C)
Description: Lowest cost highest inventory general purpose commodity NBR compound. Compare to Parker N1470-70 and N0674-70 and Parco 4200-70 and 4900-70. Available in nearly any color and hardness.
Compound: B1001Datasheet: View DatasheetHardness: 90Color: BlackLow Temp:
-30 °F
(-35 °C)
High Temp:
250 °F
(125 °C)
Description: General purpose, higher pressure applications. Compare to Parker N0552-90 and N1490-90 and Parco 4200-90 and 4900-90.
Compound: B1002Datasheet: View DatasheetHardness: 70Color: BlackLow Temp:
-30 °F
(-35 °C)
High Temp:
250 °F
(125 °C)
Description: FDA compliant per 21 CFR 177.2600. Compare to Parker N0508-75 and N1069-70.
Compound: B1005Datasheet: View DatasheetHardness: 90Color: BlackLow Temp:
-30 °F
(-35 °C)
High Temp:
250 °F
(125 °C)
Description: FDA compliant, higher hardness.
Compound: B1006Datasheet: View DatasheetHardness: 50Color: BlackLow Temp:
-30 °F
(-35 °C)
High Temp:
250 °F
(125 °C)
Description: General purpose, lower hardness for lower closure force applications. FDA compliant and alternative colors available. Compare to Parker N0299-50.
Compound: B1010Datasheet: View DatasheetHardness: 80Color: BlackLow Temp:
-30 °F
(-35 °C)
High Temp:
225 °F
(110 °C)
Description: General purpose, higher hardness. Compare to Parker N0368-80.
Compound: B1011Datasheet: View DatasheetHardness: 70Color: BlackLow Temp:
-30 °F
(-35 °C)
High Temp:
250 °F
(125 °C)
Description: Internally lubricated with PTFE to reduce friction. Silicone oil and Moly (MOS2) internal lubricants available. Alternative hardness and colors also available.
Compound: B1017Datasheet: View DatasheetHardness: 70Color: BlackLow Temp:
-35 °F
(-40 °C)
High Temp:
250 °F
(125 °C)
Description: UL 157 listed for several approved uses.
Compound: B1039Datasheet: View DatasheetHardness: 70Color: WhiteLow Temp:
-30 °F
(-35 °C)
High Temp:
250 °F
(125 °C)
Description:
Compound: B1058Datasheet: View DatasheetHardness: 70Color: BlackLow Temp:
-30 °F
(-35 °C)
High Temp:
250 °F
(125 °C)
Description: NSF 61 certified for drinking water applications.
Compound: B1063Datasheet: View DatasheetHardness: 95Color: BlackLow Temp:
-30 °F
(-35 °C)
High Temp:
250 °F
(125 °C)
Description: Very high hardness for extreme pressure applications.
Compound: B1083Datasheet: View DatasheetHardness: 70Color: BlackLow Temp:
-65 °F
(-55 °C)
High Temp:
275 °F
(135 °C)
Description: Improved lower and higher temperature resistance and improved oil resistance at higher temperature. Compare to Parker N0794-75 and M83461 and Parco 4367-70.
Compound: B1105Datasheet: View DatasheetHardness: 70Color: BlackLow Temp:
-30 °F
(-35 °C)
High Temp:
250 °F
(125 °C)
Description: Metal detectable for contamination detection sensors. FDA compliant per 21 CFR 177.2600. Formulated for food contact and life science applications. Additional colors available.
Compound: B1115Datasheet: View DatasheetHardness: 70Color: BlueLow Temp:
-40 °F
(-40 °C)
High Temp:
250 °F
(125 °C)
Description:
Compound: B1122Datasheet: View DatasheetHardness: 70Color: BlackLow Temp:
-30 °F
(-35 °C)
High Temp:
250 °F
(125 °C)
Description: NSF 51 certified for food contact.
Compound: M1000Datasheet: View DatasheetHardness: 70Color: BlackLow Temp:
-65 °F
(-55 °C)
High Temp:
275 °F
(135 °C)
Description: Mil Spec (Military specification) AMS-P-25732, MS28775-### per MIL-P-25732C-(1).
Compound: M1001Datasheet: View DatasheetHardness: 75Color: BlackLow Temp:
-65 °F
(-55 °C)
High Temp:
275 °F
(135 °C)
Description: Mil Spec (Military specification) AMS-P-83461, M83461/1-### per MIL-P-83461B#3. Improved low temperature resistance and hydraulic fluid resistance.
Compound: M1002Datasheet: View DatasheetHardness: 65Color: BlackLow Temp:
-65 °F
(-55 °C)
High Temp:
250 °F
(125 °C)
Description: Mil Spec (Military specification) MS29513-###, MS29512-##, AMS-P-5315B.
Compound: M1004Datasheet: View DatasheetHardness: 90Color: BlackLow Temp:
-65 °F
(-55 °C)
High Temp:
275 °F
(135 °C)
Description: Mil Spec (Military specification) MS28778, AMS-P-5510C.
Compound: M1005Datasheet: View DatasheetHardness: 65Color: BlackLow Temp:
-70 °F
(-60 °C)
High Temp:
200 °F
(95 °C)
Description: Mil Spec (Military specification) AMS7271, AS3578.
Compound: P1000Datasheet: View DatasheetHardness: 70Color: Yellow translucentLow Temp:
-65 °F
(-55 °C)
High Temp:
250 °F
(125 °C)
Description: High performance 70 durometer Polyurethane
Compound: P1001Datasheet: View DatasheetHardness: 90Color: Yellow translucentLow Temp:
-65 °F
(-55 °C)
High Temp:
250 °F
(125 °C)
Description: High performance 90 durometer Polyurethane
Compound: P1004Datasheet: View DatasheetHardness: 90Color: TranslucentLow Temp:
-30 °F
(-35 °C)
High Temp:
180 °F
(85 °C)
Description: General purpose 90 durometer Polyurethane
Compound: P1006Datasheet: View DatasheetHardness: 70Color: TranslucentLow Temp:
-30 °F
(-35 °C)
High Temp:
180 °F
(85 °C)
Description: General purpose 70 durometer Polyurethane
Temperature Range Comparison
Box: Base Material Family Range
Whiskers: Specialty Compounds
General Information
Full Name
Polyurethane:
Polyurethane (PU, TPU)
Buna-N:
Buna-N (NBR, Nitrile, Buna)
Short Name
Polyurethane:
Polyurethane
Buna-N:
Buna-N
Common Names
Polyurethane:
Urethane, AU, EU, PU
Buna-N:
Buna-N, Nitrile, NBR, Acrylonitrile Butadiene Rubber
Mechanical Properties
Specialty Resistances
Aliphatic Hydrocarbons
Aliphatic Hydrocarbons
Common Fuels
Common Fuels
Greases
Greases
Hydraulic Fluids
Hydraulic Fluids
Mineral Oils
Mineral Oils
Silicone Oils
Silicone Oils
Water
Water
Some Hydrocarbon Fuels
Alcohols
Some Petroleum Oils
Di-ester Lubricants
Silicone Greases
Ethylene Glycol Fluids
Brake Fluids
Petroleum Oils
Tear
Diluted Alkalies
Oxygen
Vegetable Oils
Weathering And Sunlight
Solvents
Aging
Acids
Chlorinated Hydrocarbons
Ozone
Specialty Resistances
Polyurethane
Some Hydrocarbon Fuels
Some Petroleum Oils
Silicone Greases
Brake Fluids
Tear
Oxygen
Weathering And Sunlight
Aging
Chlorinated Hydrocarbons
Ozone
Buna-N
Alcohols
Di-ester Lubricants
Ethylene Glycol Fluids
Petroleum Oils
Diluted Alkalies
Vegetable Oils
Solvents
Acids
Brands
Vibrathane®
Nipol®
Millathane®
Adiprene®
Brands
Polyurethane
Vibrathane®
Millathane®
Adiprene®
Buna-N
Nipol®
Limitations
Esters
Esters
Ketones
Ketones
Hot Water
UV Light
Alcohols
Aldehydes
Alkalis
Aromatic Fuels
Ethers
Polar Solvents
Glycols
Glycol Brake Fluids (DOT 3, 4, 5.1)
Amines
Weathering And Sunlight
Steam
Non-flammable Hydraulic Fluids
Acids
Chlorinated Hydrocarbons
Aromatic Hydrocarbons
Limitations
Polyurethane
Hot Water
Alcohols
Alkalis
Ethers
Glycols
Amines
Steam
Acids
Buna-N
UV Light
Aldehydes
Aromatic Fuels
Polar Solvents
Glycol Brake Fluids (DOT 3, 4, 5.1)
Weathering And Sunlight
Non-flammable Hydraulic Fluids
Chlorinated Hydrocarbons
Aromatic Hydrocarbons