Common Elastomers & Their Characteristics

​AFLAS* (TFE Propylene)

Trade Name: 
     *Above...............................................................................3M

This recently introduced material is unique due to its resistance to petroleum products, steam, phosphate esters and brake fluids. In some respects, it exhibits media compatibility properties similar to ethylene propylene and fluorocarbon. It has fair resistance to brake fluids and phosphate esters while exhibiting good resistance to petroleum oils. This material is finding interest for seal applications requiring petroleum resistance, steam and ammine resistance such as those applications encountered in the petroleum industry. Additional interest is being generated in applications requiring petroleum and brake fluid resistance or petroleum and phosphate ester resistance. The temperature service range for this material is -20°F to +400°F.
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Applications: 
Petroleum fluids & steam 
Petroleum fluids & ammines 
Petroleum fluids & brake fluids 
Petroleum fluids & phosphate ester

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​ETHYLENE PROPYLENE (EPM, EPDM)

(Ethylene Propylene Copolymer)

Trade Names: 
   Nordel . . . . . . . . . . . . . DuPont Dow 
   Vistalon . . . . . . . . . . . . Exxon Chemical 
   Epsyn . . . . . . . . . . . . . .Copolymer Rubber 
   Royalene . . . . . . . . . . . Uniroyal

This material was introduced in 1961 and found broad acceptance in application requiring excellent resistance to Skydrol and other phosphate ester fluids at higher temperatures. In addition, compounds of this material exhibit excellent resistance to automotive brake fluids and steam.
The temperature service range for these compounds is -65°F to +300°F.

Applications:
Automotive Brake
Water/Hot Water
Steam (to 400°F) 
Silicone Fluids 
Some Acids (Dilute) 
Ketones 
Phosphate Esters such as Skydrol

Non-Compatible:
Fluids Petroleum Fluids ​
Diester Lubricants

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FLUOROCARBON (FKM)

(Vinylidene fluoride-hexafluoropropylene)

Trade Names: 
   Fluorel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3M 
   Viton . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  DuPont-Dow

Compounds of these polymers exhibit excellent resistance to petroleum products, low compression set and high temperature resistance. The low temperature capability is somewhat restricted, however, in some case the flow temperature sealing capability may be increased by specific design parameters. These materials meet the stringent requirements of Military Specifications Mil-R83248 and Aerospace Specifications AMS 7278, AMS 7279, and AMS 7280. They are especially good for hard vacuum service and low gas permeability. The normal temperature service range in fluorocarbon is -20°F to +400°F / + 450°F.

Media Compatibility
Petroleum Fluids
Diester Lubricants
Silicone Fluids
Halogenated hydrocarbons (Above 212°F)
Some Acids
Selected Fluids  ​

Non-Compatible: 
​Skydrol ​
Ammines ​
Ketones 
Hot Water
Steam
Brake Fluids

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​FLUOROSILICONE (FVMQ)

Trade Names: 
   LS  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Dow 
   FSE  . . . . . . . . . . . . . . . . . . . . . . . . . . . .GE

​These polymers exhibit good low/high temperature resistance with excellent resistance to petroleum oils and fuels. They are used in aerospace applications for fuel systems and systems requiring resistance to diester base lubricants to 350°F. Due to the limited strength and abrasion resistance of these materials, they are generally recommended for static applications only. The sealing temperature service range is -80°F to +350/400°F.

Applications 
Petroleum oils & fuels 
Dry Heat/Oil

Non-Compatible 
Phosphate esters 
Dynamic applications

​NEOPRENE (CR) CHLOROPRENE

Trade Names: 
   Bayprene  . . . . . . . . . . . . .  Mobay 
   Butchlor . . . . . . . . . . . . . . . Ditsugil

​This was the earliest of the volume American synthetic rubbers. Compounds from neoprene exhibit fair oil resistance, good ozone and weather resistance. Due to the excellent resistance to refrigerants such as Freon, neoprene compounds are used in refrigeration systems. The sealing temperature service range for these compounds is -65°F to +250/300°F.
​

Applications 
Refrigerants (freons 
High Aniline Point Oils 
Weather and Ozone 
Ammonia Gas 
Silicate Esters

Non-Compatible 
Phosphate esters 
Ketones 
Brake Fluids

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NITRILE (NBR or Buna N)

(Acrylonitrile-Butadiene Copolymers)

Trade Names: 
   Chemigum  . . . . . . . . . . . . . . Goodyear 
   Hycar  . . . . . . . . . . . . . . . . . .Zeon Chemical 
   Krynac  . . . . . . . . . . . . . . . . .Polysar 
   Ny Syn  . . . . . . . . . . . . . . . . .Copolymer 
   Paracril  . . . . . . . . . . . . . . . . .Uniroyal 
   Perbunan  . . . . . . . . . . . . . . . Mobay

Compounds of these polymers are the backbone of the O-Ring line. Polymers vary from 18 percent to 50 percent acrylonitrile content. Resistance to petroleum products increases as acrylonitrile increases; conversely, low temperature flexibility decreases. Government specifications require low acrylonitrile.

Nitrile Compounds can exhibit excellent compression set, tear and abrasion resistance. Unless especially compounded, they do not have good resistance to ozone, sunlight, or weather. They should not be stored near motors or other ozone generating electrical equipment. They should be kept from direct sunlight. Compounds from nitrile rubber can exhibit a temperature range of -65°F to +300°F, although no one formulation may exhibit the total range.

Media Compatibility 
Petroleum Fluids 
Water (212°F) 
Silicone fluids 
Ethylene Glycol 
General Purpose

Non-Compatible 
Phosphate esters 
Ketone 
Brake fluids 
Strong Acids 
O-zone or Weathering

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HIGHLY SATURATED NITRILE (HSN)

Trade Names: 
   Therban . . . . . . . . . . . . . . Mobay 
   Zetpol  . . . . . . . . . . . . . . . Zeon Chemical 
   Tornac  . . . . . . . . . . . . . .  Polysar

This material is a highly saturated nitrile.
​
Therban exhibits excellent abrasion, compression set, tensile, and tear properties. Unlike standard nitriles, it exhibits resistance to ozone, sunlight, and other atmospheric conditions. This material also exhibits vastly improved resistance to heat aging in the 300°F range and, for short periods, up to 350°F. Presently available material exhibits a low temperature range to -40°F.

Applications 
Petroleum Fluids 
Water 
Silicone Fluids 
Ethylene Glycol 
Ozone & Weathering 
Amines 
Automotive Freon "R134A"

Non-Compatible 
Phosphate Esters 
Ketones 
Brake Fluids 
Strong Acids 
Keronsene 
Methanol/Ethanol Blends

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​SILICONE (VMQ)

Trade Names: 
   Silastic  . . . . . . . . . . . . . . .Dow 
   None  . . . . . . . . . . . . . . . .General Electric 
   None  . . . . . . . . . . . . . . . .Stauffer-Wacker 
   None . . . . . . . . . . . . . . . . Union Carbide

Silicones are noted for their excellent heat resistance, and are utilized in applications which expose seals to high temperature dry heat. They are not recommended for dynamic applications due to their relatively poor tensile and tear strength. They exhibit the best low temperature flexibility of all elastomers and can be used in static applications to -150°F. Silicones should be considered to be non-petroleum resistant, but can be used in specific high aniline point petroleum oils. The temperature service range for silicone compounds is -80°F to 450°F (All silicone formulations do not exhibit the capability of this entire range).

Applications 
High temperature (Dry heat) 
Low Temperature 
High Analine point oil

Non-Compatible 
Most petroleum oils 
Ketones 
Dynamic applications

Assembly Solutions, Inc. has hundreds of different compounds used for our customers' custom molded parts. Below is a list of some of the other compounds. If you would like to request a quote, email sales@asolutionsinc.com

• Butyl (IIR)
• Hydrin® (ECO) Epichlorohydrin
• Hydrogenated Nitrile (HNBR)
• Perfluoroelastomers (FFKM)
• Polyacrylate (ACM)
• Polyurethane (AU/AE)
• Styrene Butadiene (SBR or Buna-S)
• Teflon® (FEP) Polytetrafluoroethylene
• Vamac® (AEM) Ethylene Acrylic​