Materials / Compare
Plastic PMMA vs. Rubber
Compare Plastic PMMA 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 | not given (tensile used) | not given (tensile used) |
| Ultimate tensile strength | 80MPasourcetypical, 23 °C | 23MPasourcetypical |
| Compressive strength | 110MPasourcecompressive yield stress, typical | not sourced |
| Flexural strength | 115MPasourcetypical | not sourced |
| Elongation at break | 5.5%sourcetypical | 830%sourcetypical151x more ductile |
| Young's modulus (stiffness) | 3.3GPasourcetypical, short-term | not sourced |
| Density | 1,190kg/m³sourcetypical | 960kg/m³sourcetypical (specific gravity) |
| Strength to weight | 67.2kN·m/kg2.81x higher | 24kN·m/kg |
| Stiffness to weight | 2.77MN·m/kg | not sourced |
| Poisson's ratio | 0.37sourcetypical | 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 | 1.2GPa | not sourced |
| Bulk modulus | 4.23GPa | not sourced |
| Speed of sound | 1,665m/s | not sourced |
| Thermal | ||
| Thermal conductivity | 0.19W/m·Ksourcetypical | 0.151W/m·Ksourcegovernment selected value (US Army Natick Laboratories TR 66-49-PR, 1966), soft vulcanized natural rubber, 25 °C |
| Thermal expansion | 70µm/m·Ksource0-50 °C | not sourced |
| 100 mm part over a 50 °C swing | 350µm growth | not sourced |
| Specific heat | 1,470J/kg·Ksourcetypical | 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) | 0.109mm²/s30% faster | 0.0836mm²/s |
| Thermal shock resistance | 41.5W/m | not sourced |
| Max service temperature | 80°Csourcemax. permanent service temperature | 70°Csourcecontinuous use operating range |
| Values for | Röhm PLEXIGLAS GS 0F00 cast acrylic sheet, typical values at 23 °C / 50 % RH (Röhm Technical Information Ref. No. 211-1) | 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 PMMA stronger than Rubber?
Plastic PMMA is stronger: its tensile strength is 80 MPa against 23 MPa for Rubber (3.48x).
Which is lighter, Plastic PMMA or Rubber?
Rubber is lighter: 960 kg/m³ against 1,190 kg/m³ for Plastic PMMA.
Which is lighter for the same job, Plastic PMMA or Rubber?
For the same stiffness or strength: Plastic PMMA is lighter for a strong rod or tie, strong beam, strong panel or plate.
| Part that must be | Plastic PMMA | Rubber |
|---|---|---|
| Strong rod or tie | lighter | 2.81x heavier |
| Strong beam | lighter | 1.85x heavier |
| Strong panel or plate | lighter | 1.5x heavier |
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 is more ductile, Plastic PMMA or Rubber?
Rubber stretches further before it breaks: 830% elongation at break against 5.5% for Plastic PMMA.
Which conducts heat better, Plastic PMMA or Rubber?
Plastic PMMA conducts heat better: 0.19 W/m·K against 0.151 W/m·K for Rubber.