Rubbers or elastomers are complex materials that exhibit unique combinations of useful properties. The first and foremost property is elasticity. All elastomers have the ability to deform substantially by stretching, compression or torsion and then snap back to almost their original shape after removal of the force causing the deformation.

Besides elastic recovery, the majority of elastomers possess other useful properties, including:

• low permeability to air, several gasses, water and steam;
• good electrical and thermal insulation;
• good mechanical properties;
• the capability of adhering to metal and plastics.

Also, by proper selection of compounding ingredients, products with improved or specific properties can be designed to meet a wide variety of service conditions. We have more than 450 different elastomer materials in our program and our elastomer types have been developed to create the best mechanical and chemical properties for specific applications. For details about the unique compound properties of our elastomer materials, please contact one of our material experts or click for more information on the specific materials below.

NewDealSeals standard elastomer materials:

• Acryl-Nitrile-Butadiene Rubber (NBR)
• Chloroprene Rubber (CR)
• Ethylene Propylene Rubber (EPM, EPDM)
• Fluorocarbon Rubber (FKM)
• Fluorosilicone Rubber (FVMQ)
• Hydrogenated Nitrile Butadiene Rubber (HNBR)
• Perfluorinated Rubber (FFKM)
• Polyurethane-Rubber (AU, EU)
• Silicone Rubber (LSR, Q, MQ, VMQ)
• Styrol Butadiene Rubber (SBR)

Trade names:

• Perbunan® (Bayer AG)
• Chemigum® (Goodyear)
• Europrene N® (Enichem)
• Nipol N® (Nippon Zeon)

Nitrile rubber (NBR) is the general term for an acryl-nitrile butadiene mixed polymer. The acryl-nitrile content varies in technical products (18 to 50%) and influences the properties of the elastomer. The higher the acryl-nitrile content the better the resistance to oil and fuel. At the same time, the elasticity and the compression set is adversely affected. Often a compromise is drawn and a medium acryl-nitrile content is selected.

NBR has good mechanical properties when compared with other elastomers and a high wear resistance. NBR is not resistant to weathering and ozone.

Heat resistance: up to +100°C, shorter life +120°C (at increased temperatures the speed of ageing accelerates, ageing in oil occurs at slower rate than in hot air)
Cold flexibility: according to recipe between -20°C and -55°C

Chemical resistance to:

• aliphatic hydrocarbons (propane, butane, petroleum oil, mineral oil and grease, Diesel fuel, fuel oils);
• vegetable and mineral oils and greases;
• HFA, HFB and HFC fluids;
• many diluted acids, alkali, salt solutions at low temperatures;
• water (special compounds up to +100°C).

Not compatible with:

• fuels of high aromatic content (for super fuels a special compound must be used);
• aromatic hydrocarbons (benzene);
• chlorinated hydrocarbons (benzene);
• chlorinated hydrocarbons (trichlorethylene);
• polar solvents (ketone, acetone, acetic acid, ethylene-ester);
• strong acids;
• brake fluid with glycol base;
• ozone, weather and ageing resistant.

Trade names:

• Neoprene® (DuPont)
• Baypren® (Bayer AG)

Chloroprene was the first synthetic rubber and shows in general good ozone, ageing and chemical resistance, and good mechanical properties over a wide temperature range.

Heat resistance: up to appr. 100°C (120°C)
Cold flexibility: down to appr. -40°C

Chemical resistance to:

• mineral oil on paraffin base with low DVI;
• silicone oil and grease;
• water and water solvents at low temperatures;
• refrigerants (ammonia, carbon dioxide, freon);
• improved ozone, weathering and ageing resistance compared with NBR.

Limited compatibility:

• naphthene based mineral oil (ASTM oils no 2 and no 3);
• low molecular aliphatic hydrocarbons (propane, butane, fuel);
• brake fluids on glycol base.

Not compatible with:

• aromatic hydrocarbons (benzene);
• chlorinated hydrocarbons (trichloroethylene);
• polar solvents (ketone, ester, ether, acetone).

(earlier abbreviations: APK, APTK, EPR)

Trade names:

• Buna EP® (Chem. Werke Hüls)
• Keltan® (DSM)
• Dutral® (Montecatini)
• Nordel® (DuPont)
• Vistalon® (Enjay Chemical)

EPM is a rubber manufactured as a copolymer of ethylene and propylene. Ethylene-propylene-diene rubber (EPDM) is produced using a third monomer and is particularly useful to seal phosphate-ester hydraulic fluids and in brake systems which use fluid with glycol base.

Heat resistance: up to 150°C (max. 180°C in water and water steam)
Cold flexibility: down to appr. -50°C

Chemical resistance to:

• hot water and steam up to +150°C, special compounds up to +180°C;
• brake fluids on glycol base up to +150°C;
• many organic and inorganic acids;
• cleaning agents, soda and potassium alkalis;
• hydraulic fluids based on phosphate-ester (HFD-R);
• silicone oil and grease;
• many polar solvents (alcohols, ketones, esters);
• Skydrol 500 and 7000;
• ozone, ageing and weather resistant.

Not compatible with:

• mineral oil products (oils, greases and fuels).

Trade names:

• Viton® (DuPont)
• Fluorel® (Dyneon)
• Tecnoflon® (Ausimont)
• Dai-el® (Daikon)

Fluorocarbon rubber is the most significant compound development in sealing materials to come out of the 1950's and is noted for its wide range of applications. FKM has an excellent resistance to high temperatures, ozone, oxygen, mineral oil, synthetic hydraulic fluids, fuels aromatics and many organic solvents and chemicals. The low temperature resistance is not favourable and lies for static application at appr. -25°C (in certain applications freedom from leakage has been achieved down to -40°C). Under dynamic conditions the lowest temperature expected is between -15°C and -20°C. The gas permeability is very low and similar to butyl rubber. Special FPM compounds have a higher resistance to acids, fuels, water and steam.

Heat resistance: up to 200°C and higher temperature with shorter lifetime
Cold flexibility: down to -25°C (partially -40°C)

Chemical resistance to:

• mineral oil and grease, low swelling in ASTM oils no. 1 through 3;
• non-flammable hydraulic fuels in the group HFD;
• silicone oil and grease;
• mineral and vegetable oil and grease;
• aliphatic hydrocarbons (fuel, butane, propane, natural gas);
• aromatic hydrocarbons (benzene, toluene);
• chlorinated hydrocarbons (trichloroethylene and carbon tetrachloride);
• fuels, also fuels with methanol content;
• high vacuum;
• very good ozone, weather and ageing resistance.

Not compatible with:

• polar solvents (acetone, methyl ether, ketone, ethyl acetate, diathyl ether, dioxane);
• Skydrol 500 and 7000;
• brake fluids on glycol base;
• ammonia gas, amine alkalis;
• superheated steam;
• low molecular organic acids (formic and acetic acids).

Trade name:

• Silastic® (Dow Corning)

FVMQ contains trifluoropropyl groups next to the methyl groups. The mechanical and physical properties are very similar to VMQ. However, FVMQ offers an improved fuel and mineral oil resistance but poor hot air resistance when compared with VMQ.

Heat resistance: up to 175°C (200°C max.)
Cold flexibility: down to appr. -55°C

Chemical resistance to: same as for MVQ, additionally compatible with:

• aromatic mineral oils (e.g. ASTM oil no. 3);
• fuels;
• low molecular aromatic hydrocarbons (e.g. benzene, toluene).

Trade names:

• Therban® (Bayer AG)
• Zetpol® (Nippon Zeon)

HNBR is a synthetic rubber that results from the hydrogenation of nitrile rubber (NBR). In this process the chemical double bonds in the NBR primary polymer chain undergo a hydrogenation process and therefore the term "hydrogenated nitrile" (HNBR) is used. The allowable temperature range extends to 150°C with short periods at higher temperature possible. By following design guidelines, effective sealing can be achieved at -40°C for static applications. For dynamic applications operating temperatures are limited to above -20°C. HNBR compounds possess superior mechanical characteristics, particularly high strength. For sealing applications this is an advantage as it prevents extrusion and wear.

Heat resistance: up to +100°C
Cold flexibility: down to appr. -40°C (down to appr. -20°C for dynamic applications)

Chemical resistance to: same as for NBR, additionally compatible with:

• dilute acids, bases and salt solutions at moderate temperatures;
• water and steam up to 150°C;
• ozone, aging and weathering.

Trade names:

• Fluorezi® (NewDealSeals)
• Kalrez® (DuPont)

FFKM rubber has the chemical properties of PTFE (Teflon®) and the elastic properties of FKM rubber. The processing of Perfluor Rubber is exceptionally difficult. Perfluorinated Rubber is only used in seldom cases because the price of the raw material is many times higher than Fluorocarbon (FKM). Normally alternative elastomers can be selected, FFKM is only being selected in exceptional cases.

Heat resistance: up to 310°C
Cold resistance: up to -15°C

Chemical resistance to:

• to nearly all chemicals;
• oxygen, ozone, weather and aging;
• exceptionally low weight loss in high vacuums at high temperatures.

Not compatible with:

• medium containing fluor connections (e.g. Freon 11, 12, 13, 113, 114).

Trade name:

• Urepan® (Bayer AG)

Considering the recipe of the particular polyole, one must differentiate between polyester urethane (AU) and polyester urethane (EU). EU shows better resistance to hydraulics. Polyurethane elastomers demonstrate in comparison with any other elastomers excellent wear resistance, high tensile strength and high elasticity. The permeability is good and comparable with butyl rubber.

Heat resistance: up to appr. 90°C
Cold flexibility: down to appr. -40°C

Chemical resistance to:

• pure aliphatic hydrocarbons (propane, butane, fuel) and impurities (such as moisture, alcohol, acid or alkaline combinations) can cause chemical attack of the polyurethane;
• mineral oil and grease (particular additives can produce chemical attack upon the compound);
• silicone oil and grease;
• water up to +50°C;
• ozone and ageing resistant.

Not compatible with:

• ketone, ester, ether, alcohol, glycol;
• hot water, steam alkalis, amine, acid.

Trade names:

• Silopren® (Bayer AG)
• Silastic® (Dow Corning STI)
• Elastosil® (Wacker)

The term silicone rubber covers a large group of materials in which methyl-vinyl-silicone (VMQ) is often central. Also Liquid Silicone Rubbers (LSR), which could be various coloured and are produced as two-component-compounds, belongs to this category. Silicone elastomers as a group have a relatively poor tensile strength, tear resistance and wear resistance. However, they have many special properties: Silicones in general have good heat resistance up to +230°C and good cold flexibility down to -60°C, weathering resistance, good insulating and physiologically neutral properties.

Heat resistance: up to appr. 210°C (special compounds up to 230°C)
Cold flexibility: down to appr. -60/-55°C (special compounds down to -100°C)

Chemical resistance to:

• engine and transmission oil (e.g. ASTM oil no 1);
• animal and vegetable oil and grease;
• brake fluid (non-petroleum base);
• brake fluid (non-petroleum base);
• fire-resistant hydraulic fluid, HFD-R and HFD-S;
• high molecular chlorinated aromatic hydrocarbons;
• (e.g. clophene), chlordiphenyl (incl. flame-resistant insulators, coolant for transformers);
• water up to +100°C;
• diluted salt solutions;
• ozone, ageing and weather resistant.

Not compatible with:

• superheated water steam over +120°C;
• acids and alkalis;
• low molecular chlorinated hydrocarbons (e.g. trichloroethylene);
• aromatic mineral oil;
• fuel;
• aromatic hydrocarbons (e.g. benzene, toluene).

Trade names:

• Intol® (Enichem)
• Polysar S® (Bayer AG)

SBR probably is better known under its old names Buna S or GRS (Government Rubber Styrene) and was first produced under government control between 1930 and 1950 replacing natural rubber. The basic monomers butadiene and styrol amount to appr. 23,5%. About one third of the world output of SBR is used in the tire production. SBR seals are mostly used in seals for non-mineral oil based brake fluid.

Heat resistance: up to appr. 100°C
Cold flexibility: down to appr. -50°C

Chemical resistance to:

• water, alcohol, glycol and certain ketones (e.g. acetone);
• brake fluid with non-mineral oil base;
• silicone oil and grease;
• diluted water solutions, weak acting acids.

Not compatible with:

• mineral oil and grease fuels;
• aliphatic hydrocarbons like benzene, toluene, xylol;
• chlorinated hydrocarbons like chloroform, thrichlorethylene, tetrachloride;
• oxidizing media like nitric acid, chromic acid hydrogen peroxide, chlorine, bromine.