NR
Natural Rubber (cis-1,4-polyisoprene)
Glass Transition (Tg)
-70 °C
Melting Point (Tm)
—
Density
0.93 g/cm³
CAS Number
9006-04-6
Recycling Code
None
Category
Elastomer
Repeat Unit
–[CH₂–C(CH₃)=CH–CH₂]ₙ– (cis)
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
Outstanding tear strength, resilience and fatigue life; strain-induced crystallisation gives self-reinforcement; poor ozone, oil and heat resistance.
Applications
Truck and aircraft tyres, engine mounts, seismic bearings, gloves.