General Properties
Short Name:
Name:
HNBR
Hydrogenated acrylonitrile-butadiene rubber
Hydrogenated acrylonitrile butadiene rubber (HNBR) is a saturated (or only slightly unsaturated) copolymer of acrylonitrile and butadiene and is obtained by selective hydrogenation of the butadiene groups of NBR (see page 162). Due to fewer double bonds, it is considerably more inert than NBR.
Structural Formula
Properties
| Glass Transition Temperature | -30 to -10°C |
|---|---|
| Melting Temperature | - |
| Melting Enthalpy | - |
| Decomposition Temperature | 465 to 480°C |
| Young's Modulus | 15 to 25 MPa |
| Coefficient of Linear Thermal Expansion | 225 to 260 *10-6/K |
| Specific Heat Capacity | - |
| Thermal Conductivity | - |
| Density | 0.92 to 1.00 g/cm³ |
| Morphology | Amorphous rubber |
| General properties | Very good oil and gas resistance (like for NBR). High ozone resistance. Good abrasion resistance. Higher temperature, aging and weather resistance than NBR |
| Processing | Cross-linking by means of sulfur, peroxides or by radiation |
| Applications | Friction linings. Seals. Cables. Profiles |
NETZSCH Measurement
| Instrument | DSC 204 F1 Phoenix® |
| Sample Mass | 12.40 mg |
| Isothermal Phase | 8 min / 3 min / 8 min |
| Heating/Colling Rates | 10 K/min |
| Crucible | Al, pierced lid |
| Atmosphere | N2 (40 ml/min) |
Evaluation
HNBR is an entirely amorphous elastomer with a glass transition (midpoint) of -23°C in both the 1st heating (blue) and 2nd heating (red) with a step height (Δcp) of 0.38 J/(g*K) each.