HDPE
High-Density Polyethylene
Glass Transition (Tg)
-110 °C
Melting Point (Tm)
130–137 °C
Density
0.94–0.97 g/cm³
CAS Number
9002-88-4
Recycling Code
♺ 2
Category
Commodity
Repeat Unit
–[CH₂–CH₂]ₙ–
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
Semi-crystalline, excellent chemical resistance, high stiffness-to-density ratio, low moisture absorption, poor UV resistance without stabilizers.
Applications
Milk jugs, pipes, geomembranes, blow-moulded containers, wood-plastic composites.