Thermoplastic comparison
Polyamide 66 (PA66, Nylon 66) vs PET
Every value below is a typical room-temperature figure with its source, test method and conditions — the same dataset that drives the calculators.
| Property | Polyamide 66 (PA66, Nylon 66) | PET | Difference |
|---|---|---|---|
| Density | 1.14 g/cm³ | 1.37 g/cm³ | PET — 20% higher |
| Young's modulus E | 3.2 GPa | 2.9 GPa | Polyamide 66 (PA66, Nylon 66) — 10% higher |
| Tensile strength | 83 MPa | 60 MPa | Polyamide 66 (PA66, Nylon 66) — 38% higher |
| Glass transition Tg | 60 °C | 76 °C | PET — 16 °C higher |
| Melting point Tm | 262 °C | 255 °C | Polyamide 66 (PA66, Nylon 66) — 7 °C higher |
Where these numbers come from
- CAMPUS plastics database — typical grade datasheet values (campusplastics.com)
- Callister & Rethwisch, Materials Science and Engineering, 10th ed.
Typical room-temperature values for learning and preliminary design; grades vary widely and a supplier datasheet always overrides a textbook figure. Confirm against the datasheet before design work.