Materials / Compare
Plastic PMMA vs. Plastic UHMWPE
Compare Plastic PMMA vs. Plastic UHMWPE 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) | 20MPasourcetypical, tensile stress at yield ISO 527, 50 mm/min |
| Ultimate tensile strength | 80MPasourcetypical, 23 °C | 43MPasourcetypical, tensile stress at break ISO 527, 50 mm/min |
| Compressive strength | 110MPasourcecompressive yield stress, typical | not sourced |
| Flexural strength | 115MPasourcetypical | not sourced |
| Elongation at break | 5.5%sourcetypical | 465%sourcetypical, nominal elongation at break ISO 527 |
| Young's modulus (stiffness) | 3.3GPasourcetypical, short-term | 0.66GPasourcetypical, tensile modulus ISO 527, 1 mm/min |
| Density | 1,190kg/m³sourcetypical | 930kg/m³sourcetypical28% lighter |
| Strength to weight | 67.2kN·m/kg3.13x higher | 21.5kN·m/kg |
| Stiffness to weight | 2.77MN·m/kg3.91x higher | 0.71MN·m/kg |
| Poisson's ratio | 0.37sourcetypical | not sourced |
| Shear modulus | 1.2GPa | not sourced |
| Bulk modulus | 4.23GPa | not sourced |
| Speed of sound | 1,665m/s | 842m/s |
| Thermal | ||
| Thermal conductivity | 0.19W/m·Ksourcetypical | 0.4W/m·Ksourcetypical, unfilled (narrative value, generic Celanese UHMWPE) |
| Thermal expansion | 70µm/m·Ksource0-50 °C | 200µm/m·Ksourcetypical, 20 to 100 °C (generic Celanese UHMWPE) |
| 100 mm part over a 50 °C swing | 350µm growth2.86x less | 1,000µm growth |
| Specific heat | 1,470J/kg·Ksourcetypical | not sourced |
| Heats up and cools (diffusivity) | 0.109mm²/s | not sourced |
| Thermal shock resistance | 41.5W/m | not sourced |
| Melting point | not sourced | 130–138°CsourceDSC 10 K/min |
| Max service temperature | 80°Csourcemax. permanent service temperature | 80°Csourcerecommended max constant operating temperature |
| Values for | Röhm PLEXIGLAS GS 0F00 cast acrylic sheet, typical values at 23 °C / 50 % RH (Röhm Technical Information Ref. No. 211-1) | Celanese GUR 4120 (avg. molecular weight 4.7x10^6 g/mol), typical values on compression-molded specimens; CTE and thermal conductivity from Celanese's generic UHMWPE guide (grade not named) |
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 Plastic UHMWPE?
Plastic PMMA is stronger: its tensile strength is 80 MPa against yield strength 20 MPa for Plastic UHMWPE (4x).
Which is lighter, Plastic PMMA or Plastic UHMWPE?
Plastic UHMWPE is lighter: 930 kg/m³ against 1,190 kg/m³ for Plastic PMMA.
Which is stiffer, Plastic PMMA or Plastic UHMWPE?
Plastic PMMA is stiffer: Young's modulus 3.3 GPa against 0.66 GPa for Plastic UHMWPE, so the same part in Plastic PMMA deflects less under the same load.
Which is lighter for the same job, Plastic PMMA or Plastic UHMWPE?
For the same stiffness or strength: Plastic PMMA is lighter for a stiff rod or tie (tension), stiff beam (bending), stiff panel or plate, strong rod or tie, strong beam, strong panel or plate.
| Part that must be | Plastic PMMA | Plastic UHMWPE |
|---|---|---|
| Stiff rod or tie (tension) | lighter | 3.91x heavier |
| Stiff beam (bending) | lighter | 1.75x heavier |
| Stiff panel or plate | lighter | 34% heavier |
| Strong rod or tie | lighter | 3.13x heavier |
| Strong beam | lighter | 1.97x heavier |
| Strong panel or plate | lighter | 1.56x 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 conducts heat better, Plastic PMMA or Plastic UHMWPE?
Plastic UHMWPE conducts heat better: 0.4 W/m·K against 0.19 W/m·K for Plastic PMMA.
Which expands less with temperature?
Plastic PMMA expands less: 70 µm/m·K against 200 µm/m·K for Plastic UHMWPE.