NBR
Nitrile Rubber
Glass Transition (Tg)
-40 to -20 °C
Melting Point (Tm)
—
Density
0.98–1.00 g/cm³
CAS Number
9003-18-3
Recycling Code
None
Category
Elastomer
Repeat Unit
–[CH₂–CH=CH–CH₂]ₓ–[CH₂–CH(CN)]ᵧ–
The repeating unit is the smallest structural fragment whose repetition builds the whole chain. Subscripts show the relative share of each unit in copolymers.
Key Properties
Oil resistance rises and low-temperature flexibility falls as acrylonitrile content increases (18–50 %); poor ozone resistance.
Applications
Fuel hoses, O-rings, disposable gloves, oil seals.