EVA vs. FEP
Both EVA and FEP are thermoplastics. There are 14 material properties with values for both materials. Properties with values for just one material (18, in this case) are not shown. Please note that the two materials have significantly dissimilar densities. This means that additional care is required when interpreting the data, because some material properties are based on units of mass, while others are based on units of area or volume.
For each property being compared, the top bar is EVA and the bottom bar is FEP.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 0.015 to 0.080 | |
| 0.43 |
| Elongation at Break, % | 300 to 800 | |
| 300 |
| Tensile Strength: Ultimate (UTS), MPa | 3.0 to 35 | |
| 20 |
Thermal Properties
| Melting Onset (Solidus), °C | 55 to 95 | |
| 260 |
| Specific Heat Capacity, J/kg-K | 1400 | |
| 1170 |
| Thermal Conductivity, W/m-K | 0.34 | |
| 0.22 |
Electrical Properties
| Dielectric Constant (Relative Permittivity) At 1 Hz | 2.8 | |
| 1.9 |
| Dielectric Strength (Breakdown Potential), kV/mm | 21 | |
| 22 |
Otherwise Unclassified Properties
| Density, g/cm3 | 0.93 to 1.0 | |
| 2.1 |
Common Calculations
| Stiffness to Weight: Axial, points | 0.0087 to 0.048 | |
| 0.11 |
| Stiffness to Weight: Bending, points | 8.6 to 15 | |
| 12 |
| Strength to Weight: Axial, points | 0.87 to 10 | |
| 2.6 |
| Strength to Weight: Bending, points | 4.8 to 26 | |
| 7.6 |
| Thermal Diffusivity, mm2/s | 0.25 to 0.26 | |
| 0.088 |