PET vs. Thermoset PI
PET belongs to the thermoplastics classification, while thermoset PI belongs to the thermoset plastics. There are 14 material properties with values for both materials. Properties with values for just one material (15, in this case) are not shown.
For each property being compared, the top bar is PET and the bottom bar is thermoset PI.
Metric UnitsUS Customary Units
Mechanical Properties
| Elongation at Break, % | 2.5 to 70 | |
| 2.0 to 5.9 |
| Flexural Modulus, GPa | 8.3 to 14 | |
| 3.1 to 4.8 |
| Impact Strength: Notched Izod, J/m | 43 to 85 | |
| 21 to 43 |
| Tensile Strength: Ultimate (UTS), MPa | 60 to 140 | |
| 37 to 81 |
Thermal Properties
| Glass Transition Temperature, °C | 70 | |
| 360 |
| Maximum Temperature: Autoignition, °C | 410 | |
| 380 |
| Maximum Temperature: Decomposition, °C | 390 | |
| 330 |
| Maximum Temperature: Mechanical, °C | 80 | |
| 260 |
| Specific Heat Capacity, J/kg-K | 1000 to 1150 | |
| 1130 |
Otherwise Unclassified Properties
| Density, g/cm3 | 1.4 to 1.6 | |
| 1.4 to 1.6 |
| Limiting Oxygen Index (LOI), % | 21 | |
| 40 |
| Water Absorption At Saturation, % | 0.24 to 0.5 | |
| 3.6 |
Common Calculations
| Strength to Weight: Axial, points | 12 to 27 | |
| 6.5 to 16 |
| Strength to Weight: Bending, points | 25 to 41 | |
| 16 to 30 |