PETG vs. FEP
Both PETG and FEP are thermoplastics. There are 23 material properties with values for both materials. Properties with values for just one material (11, in this case) are not shown.
For each property being compared, the top bar is PETG and the bottom bar is FEP.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 2.2 | |
| 0.43 |
| Flexural Modulus, GPa | 2.1 | |
| 0.6 |
| Flexural Strength, MPa | 77 | |
| 24 |
| Tensile Strength: Ultimate (UTS), MPa | 53 | |
| 20 |
Thermal Properties
| Glass Transition Temperature, °C | 81 | |
| 60 |
| Heat Deflection Temperature At 1.82 MPa (264 psi), °C | 69 | |
| 50 |
| Heat Deflection Temperature At 455 kPa (66 psi), °C | 73 | |
| 70 |
| Melting Onset (Solidus), °C | 140 | |
| 260 |
| Specific Heat Capacity, J/kg-K | 1200 | |
| 1170 |
| Thermal Conductivity, W/m-K | 0.29 | |
| 0.22 |
| Thermal Expansion, µm/m-K | 68 | |
| 95 |
Electrical Properties
| Dielectric Constant (Relative Permittivity) At 1 Hz | 2.6 | |
| 1.9 |
| Dielectric Constant (Relative Permittivity) At 1 MHz | 2.4 | |
| 2.0 |
| Dielectric Strength (Breakdown Potential), kV/mm | 16 | |
| 22 |
Otherwise Unclassified Properties
| Density, g/cm3 | 1.3 | |
| 2.1 |
| Refractive Index | 1.6 | |
| 1.4 |
| Water Absorption After 24 Hours, % | 0.2 | |
| 0.010 |
Common Calculations
| Stiffness to Weight: Axial, points | 1.0 | |
| 0.11 |
| Stiffness to Weight: Bending, points | 34 | |
| 12 |
| Strength to Weight: Axial, points | 12 | |
| 2.6 |
| Strength to Weight: Bending, points | 25 | |
| 7.6 |
| Thermal Diffusivity, mm2/s | 0.19 | |
| 0.088 |
| Thermal Shock Resistance, points | 25 | |
| 35 |