MATERIALS DATABASE
Rubber Materials
Rubber is known for its memory. Rubber has the tendency to move back to its original shape after being deformed, making it an excellent sealing material for static and light dynamic applications.
FKM (Viton®)
Fluorcarbon
Also referred to as fluoroelastomers, fluorocarbon compounds are thermoset elastomers containing fluorine. Fluorocarbons make excellent general purpose O-rings.
Temp range: -25° to +204° C
Relative cost: •••••
NBR,
Nitrile
Nitrile rubber is the most commonly used elastomer for O-rings and other sealing devices. Also known as Buna N, nitrile is a copolymer of butadiene and acrylonitrile (ACN).
Temp range: -40° to +108° C
Relative cost: •••••
FFKM (Fluorezi®) Perfluoro-elastomer
FFKM has a fluorine content of more than 71%. These perfluoroelastomers with a higher fluorine content have a better chemical and heat resistance than standard fluoroelastomers do.
Temp range: -30° to +325° C
Relative cost: •••••
EPM, EPDM, Ethylene Propylene
Ethylene propylene is a copolymer of ethylene and propylene (EPM), or, in some cases, a terpolymer due to the addition of a diene monomer (EPDM).
Temp range: -55° to +150° C
Relative cost: •••••
VMQ, Silicone
Silicones are very resistant to oxygen, ozone, and UV light. They also have great flexibility retention and low compression set.
Temp range: -25° to +204° C
Relative cost: •••••
FVMQ, Fluoro-silicone
Fluorosilicone is the common name for fluorovinylmethyl silicone rubber. Fluorosilicones combine the best properties of fluorocarbons and silicones.
Temp range: -55° to +180° C
Relative cost: •••••
FEPM, Tetrafluoro-ethylene Propylene
The FEPM designation was originally directed at copolymers of tetrafluoroethylene (TFE) and propylene (P). TFE/P provides a unique combination of chemical, heat, and electrical resistance.
Temp range: -20° to +204° C
Relative cost: •••••
HNBR, Hydrogenated Nitrile
Hydrogenated nitrile results from the hydrogenation of standard nitrile. Hydrogenation is the process of adding hydrogen atoms to the butadiene segments.
Temp range: -30° to +150° C
Relative cost: •••••
PU, Polyurethane
Polyurethane is the toughest, most extrusion-resistant, and most abrasion-resistant of all elastomeric sealing materials.
Temp range: -50° to +108° C
Relative cost: •••••
CR, Chloroprene
Chemically known as polychloroprene but often referred to by the trade name Neoprene®, chloroprene was one of the first synthetic materials developed as an oil-resistant substitute for natural rubber
Temp range: -40° to +121° C
Relative cost: •••••
Temperature resistance guide
Chemical resistance guide
| FKM | NBR | FFKM | EPDM | VMQ | FVMQ | FEPM | HNBR | |
|---|---|---|---|---|---|---|---|---|
| Inorganic acids | B | C | A | B | C | C | A | C |
| Organic acids | C | B | A | B | B | D | C | B |
| Alkalis | B | B | A | D | B | B | A | B |
| Amines | D | D | A | B | A | D | A | A |
| Steam | B | D | A | B | B | C | A | C |
| Ketones | D | D | A | B | C | D | D | D |
| Esters | D | D | A | B | B | D | D | D |
| Ethers | D | D | A | D | A | A | D | A |
| Aldehydes | D | C | A | C | B | D | D | D |
| Alcohols | B | B | A | C | A | A | A | A |
| Aliphatic Hydrocarbons | A | C | A | D | D | A | B | A |
| Aromatic Hydrocarbons | A | C | A | D | D | C | D | D |
| Sour gas | B | C | A | D | C | C | A | C |
| Lubricents | A | B | A | B | A | A | A | A |
| Fluorinated fluids | D | – | C | – | D | C | D | A |
- A = Excellent
- B = Good
- C = Average
- D = Not Recommended
PTFE MATERIALS
PTFE materials have an excellent chemical compatibility. Due to the fact that PTFE itself does not have a tendency to move back to its original shape, a energizes is often required. Its chemical compatibility and wear resistance makes it an excellent material for dynamic and high demanding static applications.
PTFE Compounds
| Color | Temperature | Application | Information | |
|---|---|---|---|---|
| NDS-100 PTFE-virgin | White | -190 to +230 °C | Chemical Industry, Food Industry | High chemical resistance Datasheet |
| NDS-123 PTFE +15% glass, +5% molybdenum disulfide | Grey | -190 to +290 °C | Medium-duty | High chemical resistance, High creep resistance, Electrical properties like virgin PTFE |
| NDS-225 PTFE +25% carbon | Black | -190 to +315 °C | Pneumatics Rotary sealing | High wear and creep resistance Datasheet |
| NDS-235 PTFE +10% carbon fibre | Black | -260 to +310 °C | Water hydraulics, Seawater, Short strokes with high frequency | Very good wear properties Datasheet |
| NDS-415 PTFE +15% graphite | Antrachite | -190 to +230 °C | Low mechanical stress, Soft sealing Surfaces | Chemical resistance |
| NDS-555 PTFE + mineral fibers | Antrachite | -200 to +260 °C | Medium and heavy mechanical stress, Hydraulic applications | Chemical, wear and creep resistance Datasheet |
| NDS-640 PTFE +40% bronze | Bronze | -156 to +260 °C | Medium and heavy mechanical stress, Hydraulic applications | Outstanding wear and creep resistance |
| NDS-660 PTFE +60% bronze | Bronze | -156 to +260 °C | Heavy mechanical stress, Hydraulic applications | Outstanding wear and creep resistance |
| NDS-750 PTFE + polyimide | Tan | -260 to +310 °C | High speed rotating applications | Use against soft metals |
