Typical Trade names:
Herclor Hercules Inc.
Hydrin B.F. Goodrich Co.
Epichlorohydrin is a recent addition to the oil resistant polymer class. Compounds of this type of
aliphatic polyethers with chlorofunctional side chains. Two basic classes, homopolymers (CO)
and copolymers (ECO) are available. Both have excellent resistance to hydro carbon oils, fuels,
and ozone. High temperature resistance...
Typical Trade names:
Silastic L.S. Dow Corning Corp.
Fluorosilicone combines the good high and low-temperature properties of silicone with basic fuel
and oil resistance. The primary uses of fluorosilicones are in fuel systems at temperatures up to
350°F (177° C), and in applications where the dry-heat resistance of silicone is required, but the
seal may...
Typical Trade Names:
Silastic Dow Corning Corp.
No Trade Name General Electric.
No Trade Name Union Carbide & Carbon
No Trade Name Stauffer Chemical Company
The silicones are a group of elastomeric materials made from silicone, oxygen, hydrogen and carbon.
As a group, the silicone has poor tensile strength, tear resistance and abrasion resistance. Special
compounds have...
Typical Trade Names:
Adiprene E.I duPont de Nemours Company
Cyanaprene American Cyanamid Co.
Elastothane Thiokol Chemical Corp.
Pellethane Upjohn Co.
Vibrathane Uniroyal
Formez Witco Chem. Co.
Polyurethane exhibit outstanding mechanical and physical properties in comparison with other
elastomers. Over a temperature range –65 to 200° F, resistance to petroleum oils, hydrocarbon fuels,
oxygen, ozone and weathering is good. However,...
Typical Trade Names:
FA Polysulfide Rubber Thiokol Chemical Corp.
ST Polysulfide Rubber Thiokol Chemical Corp.
Polysulfide Rubber was one of the earliest commercial synthetic polymers and is prepared from
dichlorides and sodium polysulfide. It has a remarkable combination of solvent resistance, low
temperature flexibility, flex-crack resistance, and oxygen and oxygen and ozone resistance. However,
heat resistance,...
Typical Trade Names: Nordel E.I. duPont de Nemours Co. Royalene Uniroyal Vistalon Exxon Chemical Co. USA Epsyn Copolymer Rubber Chemical Corp. Epcar B.F. Goodrich Co. Ethylene propylene rubber is an elastomer prepared from ethylene and propylene monomers (ethylene propylene copolymer) and at times with a small amount of a third monomer (ethylene propylene terpolymers). Although EP is a relatively new introduction to the rubber industry (1961), it has won broad acceptance in the sealing world because of its excellent resistance to Skydrol and other phosphate ester type hydraulic fluids. Ethylene propylene has a temperature range of –65 to +300 F (-54 to +149 C) for most applications. EP IS RECOMMENDED FOR: * Phosphate ester base hydraulic fluids (Skydrol, Fyrquel, Pydrayl). * Steam (to 400° F) (204° C). * Water. * Silicone oils and greases. * Dilute acids. * Dilute alkalies. * Ketones (MEK, acetone). * Alcohols. *Automotive brake fluids. EP IS NOT RECOMMENDED FOR: * Petroleum oils. * Diester base lubricants.
Last Updated on Thursday, 29 April 2010 12:22
FLUOROCARBON (FPM)
Written by Administrator
Sunday, 18 April 2010 15:04
Typical Trade Names: Fluorel Minnesota Mining & Mfg. Co. Viton E.I. duPont de Nemours Company Fluorocarbon elastomers were first introduced in the mid 1950’s. Since then they have grown to major importance patibility and temperature range, fluorocarbon rubber is the most significant single elastomer development in recent history. Its working temperature range is considered to be from –20 to +400° F (-29 to +204° C) but it will take temperature up to 600° F (316° C) for short periods of time. It has been known to seal at –65° F (-54° C) in some static applications. Newer developments have tremendously improved the compression set characteristics of this very useful material. Compounds made from fluorocarbon elastomers should be considered for use in aircraft, automotive and other mechanical devices requiring maximum resistance to deterioration by test and functional fluids. FPM IS RECOMMENDED FOR: * Petroleum oils. * Di-ester base lubricants (MIL-L-7808, MIL-L-6085). * Silicate ester base lubricants (MLO 8200, MLO 8515, OS-45). * Silicone fluids and greases. * Halogenated hydrocarbons (carbon tetrachloride, trichloroethylene). * Selected phosphate ester fluids. * Acid. FPM IS NOT RECOMMNDED FOR: * Ketones (MEK, acetone) * Skydrol 500. * Amines (UDHM, anhydrous ammonia. * Low molecular weight esters and ethers. * Hot hydrofluoric or chlorosulfonic acids.
Nitrile or BUNA N (NBR)
Written by Administrator
Sunday, 18 April 2010 14:32
Typical Trade Names: Chemigum : Goodyear Tire & Rubber Co. FR-N : Firestone Synthetic Rubber & Laytex Co. Paracril : Uniroyal Hycar : Goodrich Chemical Co. Krynac : Polystar, Ltd. Ny Syn : Copolymer Rubber & Chem. Corp. Nitrile, chemically is a copolymer of butadiene and acrylonitrile. Acrylonitrile content is varied in commercial products from 18% to 48%. As the Nitrile content increases, resistance to petroleum base oils and hydrocarbon fuels increases, but low temperature flexibility decreases. Due to its excellent resistance to petroleum products, and its ability to be compounded for service over a temperature range of –65 to +250° F(-54 to + 121° C), Nitrile is the most widely used elastomers in the seal industry today. Most military rubber specifications for fuel and oil resistant MS and AN O-rings require Nitrile base compounds. It should not be mentioned, however, that to obtain good resistance to low temperature with Nitrile compounding, it is almost always necessary to sacrifice some high temperature fuel and oil resistance. Nitrile compounds are superior to most elastomers with regard to compression set or cold flow, tear and abrasion resistance, inherently, they do not possess good resistance to ozone, sunlight or weather but this can be substantially improved through compounding. However since ozone and weather resistance are not always built in, seals from Nitrile bases should not be stored near to electric motors or other equipment which may generate ozone, or in direct sunlight.
