Buna-N, also known as Nitrile rubber, Perbunan, or NBR, is a synthetic rubber copolymer of acrylonitrile (ACN) and butadiene. Trade names include Nipol, Krynac and Europrene. Buna-N is more resistant than natural rubber to oils and acids, but has inferior strength and flexibility. It is generally resistant to aliphatic hydrocarbons. Buna-N, like natural rubber, can be attacked by ozone, aromatic hydrocarbons, ketones, esters and aldehydes.

Buna-N (Nitrile) is suitable for dynamic and static seal of o-rings in the environment containing the following chemicals: Acetamide, Acetic Anhydride, Acetylene Gas, Air below 200 C, Aluminium Chloride, Aluminium Flouride, Aluminium Nitrate, Aluminium Sulfate, Cold Gas Ammonia, Ammonium Nitrate, Ammonium Persulfate Solution, Ammonium Sulfate, Animal Oil, Argon, ASTM Fuel A, ASTM Oil One, ASTM Oil Three, ASTM Oil Two, Automatic Transmission Fluid, Beer, Benzine (Ligroin), Boric Acid, Bunker Oil, Butane, Butter, Butyl Alcohol, Calcium Carbonate, Calcium Chloride, Calcium Hydroxide, Calcium Nitrate, Calcium Sulfide, Carbon Monoxide, Castor Oil, Tung Oil China Wood Oil, Citric Acid, Cod Liver Oil, Coffee, Coolanol Monsanto, Corn Oil, Cyclohexane, Denatured Alcohol, Diesel Oil, Diethylamine Glycol, Dow Corning 550, Dow Guard, Elco 28 Lubricant, Ethane, Ethanol, Ethyl Alcohol, Ethyl Chloride, Ethyl Hexanol, Ethyl Silicate, Ethylene, Ethylene Glycol, Formaldehyde, Freon 113, Freon 114, Freon 12, Freon 13, Freon 32, Freon C318, Freon TF, Fuel Oil, Automotive Gasoline, Gelatine, Glucose, Glycerin, General Glycol, Petroleum Base Grease, Helium, Heptane, Hexane, Petroleum Base Hydraulic Oil, Hydrogen Gas, Iso Octane, Isopropanol, JP 3 MIL-J5624, JP 4 MIL-J5624, JP 5 MIL-J5624, JP 6 MIL-J5624, Kerosene, Animal Fat Lard, Linsed Oil, Liquefied Petroleum Gas (LPG), Petroleum Base Lubricating Oils, Mercuric Chloride, Mercury, Methane, Methyl Alcohol, Methyl Ether, MIL-F-25558 (RJ-1), MIL-F-25656, MIL-H-5606, MIL-H-7083, JP-5 JP-4 JP-3 MIL-J 5624, Milk, MIL-R-25576 (RP-1), Type 1 Fuel MIL-S-3136, MIL-S-81087, Mineral Oils, Naphtha, Natural Gas, Neatsfoot Oil, Gas Nitrogen, N-Pentane, Oleic Acid, Peanut Oil, Petroleum Oil, Potassium Nitrate, Potassium Sulfate, Producer Gas, Propane, Propanol, Propyl Alcohol, Transformer Oil Pyranol, Red Oil, RJ-1 (MIL-F-25558), RP-1 (MIL-R-25576), Sea Water, Silicone Grease, Silicone Oils, Sodium Bicarbonate, Sodium Carbonate, Sodium Chloride, Sodium Hydroxide, Soyabean Oil, Stearic Acid, Stoddard Solvent, Sucrose Solutions, Tannic Acid, Tartaric Acid, Type A Transmission Fluid, Turpentine, Fresh Water, Whiskey.

O-Ring material Buna-N (Nitrile) is usually suitable for static seal in the environment containing Aluminium Acetate, Anhydrous Ammonia, Hot Gas Ammonia, Ammonium Carbonate, Ammonium Chloride, Amyl Alcohol, Amyl Borate, Aromatic Fuel 50%, Askarel Transformer Oil, ASTM Oil Four, Borax Solutions, Carbitol 2, Carbonic Acid, Chlordane, Coal Tar Creosote, Crude Oil (Asphalt Base), Dichloro-Butane, Di-ester Lubricant MIL-L-7808, Ethyl Acetoacetate, Ethyl Cellulose, Ethyl Diamine, Freon 11 (M), Freon 112, Freon 114B2, Freon 502 (F22+F316), Gallic Acid, Hexyl Alcohol, Hydrazine, Hydrocyanic Acid, Iodine, Isobutyl Alcohol, Isopropyl Ether, Linoleic Acid, Malathion, Methanol, Methyl Bromide, MIL-G-25760, MIL-L-25681, Naphthalenic, N-Octane, Octyl Alcohol, Oronite 8200, Oxalic Acid, Cold Oxygen, Pine Oil, Rapeseed Oil, Silver Nitrate, Styrene Monomer, Sulfur Hexafluoride, Tertiary Butyl Alcohol, Tetrabutyl Titanate, Tetraethyl Lead, Triethanolamine, Turbine Oil, Varnish, Vinegar, Wagner 21B Brake Fluid, White Pine Tar.

O-Ring material Buna-N (Nitrile) is sometimes ok for static seal but not for dynamic seal in the environment containing chemicals such as Concentrated Ammonium Hydroxide, Amyl Chloronaphthalene, Arachlor 1248, ASTM Fuel B, ASTM Fuel C, ASTM Fuel D, Benzophenone, Bleach Liquor, Butadiene Monomer, Butyl Cellosolve, Calcium Hypochlorite, Diethylamine, Dimethyl Formamide, Ethyl Ether, Maleic Acid, Methyl Cellosolve, Radiation, Sulfurous Acid, Tetrachloroethylene, Toluene, VV-H-910.

Buna-N (Nitrile) is not suitable for o-rings exposed in the environment containing chemicals such as Acetaldehyde, Glacial Acetic Acid, Acetone, Acetophenone, Acetyl Chloride, Acrylonitrile, Alkazene, Amyl Acetate, Aniline, Aniline Oil, Benzaldehyde, Benzene, Benzene Sulfonic Acid, Benzoic Acid, Benzyl Alcohol, Benzyl Benzoate, Benzyl Chloride, Brake Fluid, Bromine Gas, Bromobenzene, Butyl Carbitol, Butyraldehyde, Carbolic Acid (Phenol), Carbon Disulfide, Carbon Tetrachloride, Cellosolve, Chloracetic Acid, Chlorinated Solvents, Chlorine Dioxide, Chlorine Trifluoride, Dry Chlorine, Wet Chlorine, Chloroform, Chlorosulfonic Acid, Chrome Plating Solution, Chromic Acid, Creosylic Acid, Diacetone, Diacetone Alcohol, Dibenzyl Ether, Dibutyl Phthalate, Dimethyl Phthalate, Dioxane, Diphenyl, Dowtherm A, Ethyl Benzene, Ethyl Benzoate, Ethyl Chlorocarbonate, Ethyl Formate, Ethyl Mercaptan, Ethyl Oxalate, Ethyl Pentachlorobenzene, Ethylene Dichloride, Ethylene Oxide, Ethylene Trichloride, Freon 21, Freon 22, Freon 31, Furan, Furfural, Furfuryl Alcohol, Hydrobromic Acid, Gas Hydrobromic Acid, Hydrochloric Acid, Hydrofluoric Acid, Hydrogen Peroxide, Hydroquinone, Isopropyl Acetate, Isopropyl Chloride, Lacquer Solvents, Lacquers, Hydraulic Fluid (Phosphate Ester Type) Lindol, Lye, Methyl Acetate, Methyl Acrylate, Methyl Butyl Ketone, Methyl Chloride, Methyl Ethyl Ketone (MEK), Methyl Isobutyl Ketone (MIBK), Methyl Methacrylate, Methyl Oleate, Methyl Propyl Salicylate, Methylene Chloride, Monovinyl Acetate, Naphthalene, N-Hexaldehyde, Nitric Acid, Nitrobenzene, Nitroethane, Nitrogen Tetroxide, Nitromethane, Nitropropane, Oleum (Fuming Sulfuric Acid), 200-400F Oxygen, Ozone, Phenylhydrazine, Phosphoric Acid, Phosphoric Trichloride, Propyl Acetate, Propylene, Propylene Oxide, 10E Pydraul, 540C 312F 230C Pydraul, 90E 65E 50E 30E Pydraul, 55 (Phosphate Ester) 53 43 Pyrogard 42, Skydrol 500, Steam to 350F, Sulfur Chloride, Dry Sulfur Dioxide Gas, Wet Sulfur Dioxide Gas, Liquefied Under Pressure Sulfur Dioxide, Sulfur Trioxide, Sulfuric Acid (Concentrated), Tertiary Butyl Mercaptan, Tetrabromoethane, Tetrachloroethane, Tetrahydrofuran, Tetralin, Xylene.