UP
Unsaturated Polyester
Glass Transition (Tg)
70–120 °C
Melting Point (Tm)
— (crosslinked)
Density
1.10–1.40 g/cm³
CAS Number
—
Recycling Code
None
Category
Thermoset
Repeat Unit
–[O–CO–CH=CH–CO–O–R]ₙ– + styrene crosslinks
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
Cheapest thermoset matrix; free-radical cure through styrene crosslinking; higher shrinkage (~7 %) and styrene emissions during cure.
Applications
GRP boat hulls, water tanks, bathroom units, cultured marble.