Materials / Compare
Plastic PTFE vs. Rubber
Compare Plastic PTFE vs. Rubber strength, stiffness, weight and thermal properties.
| Try it on a partA bracket to run stress or thermal on, free in your browser | Open in LessCAD | Open in LessCAD |
|---|---|---|
| Mechanical | ||
| Yield strength | 9MPasourcetypical yield strength at 23 °C (Teflon PTFE, Table 8) | not given (tensile used) |
| Ultimate tensile strength | 39.3MPasourcetypical, skived tape 0.13 mm | 23MPasourcetypical |
| Elongation at break | 350%sourcetypical, skived tape 0.13 mm | 830%sourcetypical |
| Young's modulus (stiffness) | not sourced | not sourced |
| Density | 2,160kg/m³sourcetypical (standard specific gravity, ASTM D4894) | 960kg/m³sourcetypical (specific gravity) |
| Strength to weight | 4.17kN·m/kg | 24kN·m/kg5.75x higher |
| Stiffness to weight | not sourced | not sourced |
| Poisson's ratio | 0.46sourcetypical, 23 °C (Teflon PTFE resins, Chemours handbook) | 0.5sourcegovernment (NBS J. Res. 68A, 1964): computed by NBS for peroxide-cured gum NR vulcanizate, 25 °C, infinitesimal deformation0.49 in the solver: the linear element locks as the ratio nears 0.5 (nearly incompressible). |
| Shear modulus | not sourced | not sourced |
| Bulk modulus | not sourced | not sourced |
| Speed of sound | not sourced | not sourced |
| Thermal | ||
| Thermal conductivity | 0.25W/m·Ksourcetypical, granular resin, 4.6 mm specimen | 0.151W/m·Ksourcegovernment selected value (US Army Natick Laboratories TR 66-49-PR, 1966), soft vulcanized natural rubber, 25 °C |
| Thermal expansion | 100µm/m·Ksourcetypical, granular resin, 23-60 °C (ASTM E228) | not sourced |
| 100 mm part over a 50 °C swing | 500µm growth | not sourced |
| Specific heat | 1,400J/kg·Ksourcetypical, granular resin, 20 °C (ASTM D4591) | 1,881J/kg·Ksourcegovernment (NBS J. Res. 68A, Table 7; values observed for unvulcanized NR by Bekkedahl and Matheson), 25 °C |
| Heats up and cools (diffusivity) | 0.0827mm²/s | 0.0836mm²/s1% faster |
| Thermal shock resistance | not sourced | not sourced |
| Melting point | 327°Csourcesecond melting peak (sintered polymer), +/-10 | not sourced |
| Max service temperature | 260°Csourceservice temperature (Chemours general Teflon PTFE statement) | 70°Csourcecontinuous use operating range |
| Values for | Chemours Teflon PTFE 7C X granular molding resin, typical values (tensile/elongation measured on 0.13 mm skived tape) | Weir Minerals Linatex Premium rubber (95 % natural rubber), typical physical properties, spec sheet WMD0118/202305 |
Every value links to the document that states it. "Not sourced" means no citable source states it (or only a specification minimum); figures computed from it are left out too.
Questions
Is Plastic PTFE stronger than Rubber?
Rubber is stronger: its tensile strength is 23 MPa against yield strength 9 MPa for Plastic PTFE (2.56x).
Which is lighter, Plastic PTFE or Rubber?
Rubber is lighter: 960 kg/m³ against 2,160 kg/m³ for Plastic PTFE.
Which is lighter for the same job, Plastic PTFE or Rubber?
For the same stiffness or strength: Rubber is lighter for a strong rod or tie, strong beam, strong panel or plate.
| Part that must be | Plastic PTFE | Rubber |
|---|---|---|
| Strong rod or tie | 5.75x heavier | lighter |
| Strong beam | 4.21x heavier | lighter |
| Strong panel or plate | 3.6x heavier | lighter |
For the same stiffness or strength, mass scales with density over stiffness (or strength) raised to a power set by how the part is loaded: 1 for a rod in tension, 1/2 for a beam in bending, 1/3 for a panel (the standard material-selection indices).
Which conducts heat better, Plastic PTFE or Rubber?
Plastic PTFE conducts heat better: 0.25 W/m·K against 0.151 W/m·K for Rubber.