PEI vs. RPU
PEI belongs to the thermoplastics classification, while RPU belongs to the thermoset plastics. There are 19 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 PEI and the bottom bar is RPU.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 3.4 to 5.6 | |
| 2.2 |
| Elongation at Break, % | 3.0 to 34 | |
| 90 |
| Flexural Modulus, GPa | 3.4 to 5.9 | |
| 2.0 |
| Flexural Strength, MPa | 140 to 210 | |
| 83 |
| Tensile Strength: Ultimate (UTS), MPa | 110 to 160 | |
| 60 |
Thermal Properties
| Maximum Temperature: Autoignition, °C | 530 | |
| 380 |
| Maximum Temperature: Decomposition, °C | 530 | |
| 270 |
| Specific Heat Capacity, J/kg-K | 1050 to 1220 | |
| 1750 |
| Thermal Conductivity, W/m-K | 0.18 to 0.23 | |
| 0.19 |
| Thermal Expansion, µm/m-K | 20 to 53 | |
| 63 |
Electrical Properties
| Dielectric Strength (Breakdown Potential), kV/mm | 30 to 33 | |
| 19 |
| Electrical Resistivity Order of Magnitude, 10x Ω-m | 14 to 15 | |
| 13 |
Otherwise Unclassified Properties
| Density, g/cm3 | 1.3 to 1.5 | |
| 1.2 |
Common Calculations
| Stiffness to Weight: Axial, points | 1.5 to 2.1 | |
| 1.0 |
| Stiffness to Weight: Bending, points | 39 | |
| 36 |
| Strength to Weight: Axial, points | 24 to 30 | |
| 14 |
| Strength to Weight: Bending, points | 40 to 44 | |
| 28 |
| Thermal Diffusivity, mm2/s | 0.11 to 0.14 | |
| 0.090 |
| Thermal Shock Resistance, points | 44 to 100 | |
| 31 |