Plastic TPU vs. Plastic UHMWPE

Compare Plastic TPU vs. Plastic UHMWPE strength, stiffness, weight and thermal properties.

Plastic UHMWPEBulk polymer (molded or machined)

Mechanical	Plastic TPU	Plastic UHMWPE
Yield strength	not given (tensile used)	20MPa1
Ultimate tensile strength	23.7MPa2	43MPa11.81x stronger
Flexural strength	4.1MPa2	not sourced
Elongation at break	not sourced	465%1
Young's modulus (stiffness)	0.067GPa2	0.66GPa19.85x stiffer
Density	1,220kg/m³2	930kg/m³131% lighter
Strength to weight	19.4kN·m/kg	21.5kN·m/kg11% higher
Stiffness to weight	0.0549MN·m/kg	0.71MN·m/kg12.9x higher
Poisson's ratio	not sourced	not sourced
Shear modulus	not sourced	not sourced
Bulk modulus	not sourced	not sourced
Speed of sound	234m/s	842m/s3.59x faster

Stiffness against densityHigher and further left: stiffer for its weight

Strength against densityHigher and further left: stronger for its weight

Thermal	Plastic TPU	Plastic UHMWPE
Thermal conductivity	not sourced	0.4W/m·K3
Thermal expansion	not sourced	200µm/m·K3
100 mm part over a 50 °C swing	not sourced	1,000µm growth
Specific heat	not sourced	not sourced
Heats up and cools (diffusivity)	not sourced	not sourced
Thermal shock resistance	not sourced	not sourced
Melting point	217°C2	DSC 10 K/min130–138°C1
Max service temperature	HDT 0.455 MPa50.3°C2	80°C1

Thermal conductivity against densityHigher and further left: spreads more heat for its weight

Thermal expansion against thermal conductivityLower and further right: warps less when heated

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Sources3 documents: Celanese, UltiMaker

Plastic TPU: Ultimaker TPU 95A, 3D-printed specimens, XY (flat); Ultimaker S5 Pro, engineering intent profile, 0.15 mm layer height, AA 0.4 print core, 100% infill, Cura 4.9, printed one-at-a-time, conditioned >=24 h at room temperature. TDS (file v5.00), April 29, 2022.
Plastic UHMWPE: 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)

1
GUR UHMW-PE Overview (GUR-015)CelanesePlastic UHMWPE · Yield strength: typical, tensile stress at yield ISO 527, 50 mm/minPlastic UHMWPE · Ultimate tensile strength: typical, tensile stress at break ISO 527, 50 mm/minPlastic UHMWPE · Elongation at break: typical, nominal elongation at break ISO 527Plastic UHMWPE · Young's modulus (stiffness): typical, tensile modulus ISO 527, 1 mm/minPlastic UHMWPE · Density: typicalPlastic UHMWPE · Melting point: DSC 10 K/minPlastic UHMWPE · Max service temperature: recommended max constant operating temperature
2
Ultimaker TPU 95A Technical Data Sheet, v5.00UltiMakerarchived copyPlastic TPU · Ultimate tensile strength: typical, stress at breakPlastic TPU · Flexural strength: typicalPlastic TPU · Young's modulus (stiffness): typicalPlastic TPU · Density: typicalPlastic TPU · Melting point: typicalPlastic TPU · Max service temperature: HDT 0.455 MPa (printed specimens)
3
GUR UHMW-PE Polymer Guide (GUR-003)Celanesearchived copyPlastic UHMWPE · Thermal conductivity: typical, unfilled (narrative value, generic Celanese UHMWPE)Plastic UHMWPE · Thermal expansion: typical, 20 to 100 °C (generic Celanese UHMWPE)

Each number points to the document that states it, with the exact basis. Values without a number are computed from the sourced ones. "Not sourced" means no citable source states it (or only a specification minimum); figures computed from it are left out too.

Plastic TPU is 3D printed: its properties depend on build direction and print settings; these are typical values.

Questions

Mechanical

Is Plastic TPU stronger than Plastic UHMWPE?

Plastic TPU is stronger: its tensile strength is 23.7 MPa against yield strength 20 MPa for Plastic UHMWPE (19%).

Which is lighter, Plastic TPU or Plastic UHMWPE?

Plastic UHMWPE is lighter: 930 kg/m³ against 1,220 kg/m³ for Plastic TPU.

Which is stiffer, Plastic TPU or Plastic UHMWPE?

Plastic UHMWPE is stiffer: Young's modulus 0.66 GPa against 0.067 GPa for Plastic TPU, so the same part in Plastic UHMWPE deflects less under the same load.

Which is lighter for the same job, Plastic TPU or Plastic UHMWPE?

For the same stiffness or strength: Plastic UHMWPE 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 TPU	Plastic UHMWPE
Stiff rod or tie (tension)	12.9x heavier	lighter
Stiff beam (bending)	4.12x heavier	lighter
Stiff panel or plate	2.81x heavier	lighter
Strong rod or tie	11% heavier	lighter
Strong beam	17% heavier	lighter
Strong panel or plate	21% 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).