ETPU is expanded thermoplastic polyurethane, the classic soft high-rebound bead foam: 57% rebound, over 90% compression recovery, still elastic at −30°C, durable under repeated impact. It has the most predictable behaviour of any elastomer here — raise the expansion ratio and rebound, tensile and elongation all go up while hardness comes down.
Current material data (confirm against the selected grade before ordering)
| Property | Current value |
|---|---|
| Molded density | 180–300 kg/m³ |
| Compression stress at 10% | 40–80 kPa |
| Long-term service temperature | 80 °C |
| Short-term dimensional stability temperature | 100 °C |
| Cold-use boundary | −30 °C |
| Thermal conductivity | 0.045–0.055 W/(m·K) |
| Rebound | 57% |
| Hardness | 35–52 Asker-C |
| Property | Value |
|---|---|
| Foam density | 180–300 kg/m³ (single bead about 140–200); molded parts 200–300 kg/m³ depending on fill |
| Expansion ratio | about 10× |
| Rebound | 57% |
| Compression recovery | over 90% — low permanent set |
| Minimum service temperature | −30°C, retaining high elasticity and softness |
| Known relationship | Expansion ratio up gives rebound up, hardness down, tensile up, elongation up |
| Molding conditions | Steam chest 0.6–2.2 bar / 110–130°C; one grade molds steam-free at 100–150°C for 1–30 min |
| Weather resistance | Must be typed: aromatic MDI-based yellows badly, aliphatic HDI/IPDI-based weathers well but costs more. Tell us if the part goes outdoors |
| Compression / tensile / elongation / tear / conductivity / max temperature | Provided with your enquiry |
Performance running midsoles
The reference application for this material.
Sports protective gear
Rebound survives being hit repeatedly.
Puncture-proof tyre inserts
Load and recovery, with no air to lose.
Why we can run it
Soft elastomer beads with a narrow molding window. DBM molds them.
Compare in detail: EPP vs ETPU foam