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EPM vs TPE

Polymer · grade comparison

EPM and TPE are both polymer grades. EPM is the stronger of the two: tensile strength 14 MPa (2.03 ksi) against 8 MPa (1.09 ksi) for TPE, about 87% more. In exchange, TPE is the more ductile: elongation 480% versus 320% for EPM. TPE is lighter (0.96 g/cm³ vs 1.12 g/cm³ for EPM) and TPE is stiffer (0.01 GPa vs 0.01 GPa).

EPMChoose it when strength drives the design, or when the part sees heat.

TPEChoose it when the part is bent, formed or impact-loaded, or when weight is the constraint.

EPM vs TPE: properties

EPMTPE

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

0.01 GPa8.7×10⁻⁴ Msi
0.01 GPa0 Msi

Shear Modulus

0 GPa2.9×10⁻⁴ Msi
0 GPa4.35×10⁻⁴ Msi

Poisson's Ratio

0.49
0.48

Tensile Strength (Ultimate)

14 MPa2 ksi
8 MPa1.1 ksi

Elongation at Break

320%
480%

Hardness, Shore A

70 Shore A
65 Shore A

Tear Strength

30 kN/m171 lbf/in
25 kN/m143 lbf/in

Compression Set (22 h, 70 °C)

18%
30%

Compressive Strength

—
3 MPa0.44 ksi

Flexural Modulus

—
0.02 GPa0 Msi

Shear Strength

—
5 MPa0.73 ksi

Hardness, Shore D

—
20 Shore D

Same in both: Bulk Modulus 2 GPa0.29 Msi

Physical

Density and transition temperatures.

Density

1.12 g/cm³0.04 lb/in³
0.96 g/cm³0.03 lb/in³

Water Absorption (24 h)

0.8%
0.3%

Melting Temperature (Tm)

—
165°C329 °F

Water Absorption (Saturation)

—
0.8%

Same in both: Glass Transition (Tg) -55°C-67 °F

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

0.25 W/m·K0.14 BTU/hr·ft·°F
0.2 W/m·K0.12 BTU/hr·ft·°F

Specific Heat Capacity

2,000 J/kg·K0.48 BTU/lb·°F
1,900 J/kg·K0.45 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

180 µm/m·K100 µin/in·°F
200 µm/m·K111 µin/in·°F

Max Service Temperature (continuous)

150°C302 °F
105°C221 °F

Max Service Temperature (short-term)

175°C347 °F
135°C275 °F

Heat Deflection Temp. @ 0.45 MPa

—
55°C131 °F

Vicat Softening Point (B50)

—
60°C140 °F

Same in both: Min Service Temperature -50°C-58 °F · Limiting Oxygen Index 19%

Electrical

Conductivity and insulation.

Dielectric Strength

25 kV/mm635 V/mil
20 kV/mm508 V/mil

Dielectric Constant (1 MHz)

2.8
2.6

Dissipation Factor (1 MHz)

0.004
0.0015

Same in both: Electrical Resistivity 1×10¹³ Ω·m3.94×10²⁰ µΩ·in · Volume Resistivity 1×10¹⁵ Ω·cm

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

95 / 100
88 / 100

UV / Weathering Resistance

97 / 100
70 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

30 / 100
25 / 100

Formability (cold)

85 / 100
90 / 100

Mold Shrinkage

2.5%
1.8%

Mold Temperature (typ.)

175°C347 °F
40°C104 °F

Weldability

—
65 / 100

Polishability

—
20 / 100

Melt Flow Rate

—
20 g/10 min

Processing Melt Temperature (typ.)

—
210°C410 °F

Sustainability

Primary-production footprint per kilogram.

Embodied Carbon (primary production)

3.4 kg CO₂/kg
3.6 kg CO₂/kg

Embodied Water

110 L/kg13.2 gal/lb
130 L/kg15.6 gal/lb

Typical Recycled Content

2%
5%

Same in both: Embodied Energy (primary production) 95 MJ/kg40,843 BTU/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

12 kN·m/kg
8 kN·m/kg

Thermal Shock Resistance Index

3
1

Same in both: Specific Stiffness (E / density) 0 MN·m/kg · Thermal Diffusivity 0.1 mm²/s

Strength versus weight

Yield strength against density for every polymer grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

0.1110100123Density (g/cm³)Yield strength (MPa) — log scaleTPE

Manufacturing and finishing

CapabilityEPMTPE
Injection molding—Yes
Default condition—Shore A 30 to Shore A 90
Relative cost$$ Standard$$ Standard
Min. machined wall——
Best machined surface——
Chrome Plating (Plastic)—Yes
EMI Shielding Coating—Yes
Soft Touch Coating—Yes
Spray Painting—Yes
UV Coating—Yes

EPM vs TPE — frequently asked

Is EPM stronger than TPE?

Yes. EPM has a typical tensile strength of 14 MPa (2.03 ksi) against 8 MPa (1.09 ksi) for TPE — about 87% more.

Which is cheaper, EPM or TPE?

Both sit in the same relative cost tier ($$, standard); the part price will be decided by machining time, tolerance and quantity rather than by the material.

Which is easier to machine, EPM or TPE?

EPM, by a small margin. Both rate poor for machinability — 30/100 against 25/100 for TPE.

Ready to make it?

Upload a CAD file and FabDigit prices the part in EPM and TPE side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.

Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.