PAI
Polyamide-imide (Torlon)
Glass Transition (Tg)
275–280 °C
Melting Point (Tm)
— (amorphous)
Density
1.42 g/cm³
CAS Number
42955-03-3
Recycling Code
♺ 7
Category
High-Performance
Repeat Unit
–[CO–NH–C₆H₄–N(CO)₂–C₆H₃]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
Highest strength of any melt-processable thermoplastic at elevated temperature; requires a long post-cure to develop final properties.
Applications
Compressor vanes, thrust washers, high-load bearings, seals.