PTFE vs. PEI
Both PTFE and PEI are thermoplastics. There are 16 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 PTFE and the bottom bar is PEI.
Metric UnitsUS Customary Units
Mechanical Properties
| Compressive (Crushing) Strength, MPa | 6.9 to 24 | |
| 140 to 180 |
| Elongation at Break, % | 75 to 300 | |
| 3.0 to 34 |
| Flexural Modulus, GPa | 0.4 to 1.3 | |
| 3.4 to 5.9 |
| Flexural Strength, MPa | 13 to 50 | |
| 140 to 210 |
| Tensile Strength: Ultimate (UTS), MPa | 13 to 25 | |
| 110 to 160 |
Thermal Properties
| Heat Deflection Temperature At 1.82 MPa (264 psi), °C | 66 to 70 | |
| 200 to 210 |
| Maximum Temperature: Mechanical, °C | 260 to 270 | |
| 170 |
| Thermal Conductivity, W/m-K | 0.24 to 0.65 | |
| 0.18 to 0.23 |
| Thermal Expansion, µm/m-K | 110 to 120 | |
| 20 to 53 |
Electrical Properties
| Dielectric Constant (Relative Permittivity) At 1 MHz | 2.1 to 2.4 | |
| 3.2 to 3.7 |
| Electrical Resistivity Order of Magnitude, 10x Ω-m | 2.0 to 18 | |
| 14 to 15 |
Otherwise Unclassified Properties
| Density, g/cm3 | 2.1 to 2.3 | |
| 1.3 to 1.5 |
| Limiting Oxygen Index (LOI), % | 90 | |
| 47 to 50 |
| Water Absorption After 24 Hours, % | 0.0093 to 0.050 | |
| 0.17 to 0.25 |
Common Calculations
| Strength to Weight: Axial, points | 1.7 to 3.2 | |
| 24 to 30 |
| Strength to Weight: Bending, points | 5.7 to 8.7 | |
| 40 to 44 |