PBI vs. CAP
PBI belongs to the thermoset plastics classification, while CAP belongs to the thermoplastics. There are 17 material properties with values for both materials. Properties with values for just one material (16, in this case) are not shown.
For each property being compared, the top bar is PBI and the bottom bar is CAP.
Metric UnitsUS Customary Units
Mechanical Properties
| Elongation at Break, % | 3.0 | |
| 35 to 50 |
| Flexural Modulus, GPa | 6.5 | |
| 1.2 to 1.9 |
| Flexural Strength, MPa | 220 | |
| 29 to 56 |
| Tensile Strength: Ultimate (UTS), MPa | 160 | |
| 28 to 45 |
Thermal Properties
| Glass Transition Temperature, °C | 410 | |
| 190 |
| Heat Deflection Temperature At 1.82 MPa (264 psi), °C | 430 | |
| 65 to 80 |
| Specific Heat Capacity, J/kg-K | 930 | |
| 1480 |
| Thermal Conductivity, W/m-K | 0.41 | |
| 0.25 |
| Thermal Expansion, µm/m-K | 23 | |
| 14 |
Electrical Properties
| Dielectric Constant (Relative Permittivity) At 1 MHz | 3.8 | |
| 3.6 |
| Dielectric Strength (Breakdown Potential), kV/mm | 23 | |
| 15 |
| Electrical Resistivity Order of Magnitude, 10x Ω-m | 13 | |
| 16 |
Otherwise Unclassified Properties
| Density, g/cm3 | 1.3 | |
| 1.2 |
| Water Absorption After 24 Hours, % | 0.4 | |
| 1.4 to 1.7 |
Common Calculations
| Strength to Weight: Axial, points | 34 | |
| 6.5 to 10 |
| Strength to Weight: Bending, points | 50 | |
| 17 to 23 |
| Thermal Diffusivity, mm2/s | 0.34 | |
| 0.14 |