PVB
Polyvinyl Butyral
Glass Transition (Tg)
60–70 °C
Melting Point (Tm)
— (amorphous)
Density
1.10 g/cm³
CAS Number
63148-65-2
Recycling Code
♺ 7
Category
Functional & Smart
Repeat Unit
–[CH₂–CH–O–CH(C₃H₇)–O–CH–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
Exceptional adhesion to glass combined with high toughness — it holds shattered glass fragments together on impact.
Applications
Laminated safety glass (windscreens), PV module encapsulant.