ECO vs EPDM
Polymer · grade comparison
ECO and EPDM are both polymer grades. EPDM is the more ductile: elongation 400% versus 250% for ECO. EPDM is lighter (1.15 g/cm³ vs 1.36 g/cm³ for ECO) and EPDM conducts heat better (0.3 W/m·K vs 0.22 W/m·K). On the shop floor, EPDM sits in a lower cost tier (standard, $$) than ECO (high, $$$$).
EPDMChoose it when the part is bent, formed or impact-loaded, or when weight is the constraint.
ECO vs EPDM: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all polymer grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all polymer grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elongation at Break
Compression Set (22 h, 70 °C)
Shear Modulus
Bulk Modulus
Same in both: Elastic (Young's) Modulus 0.01 GPa8.7×10⁻⁴ Msi · Poisson's Ratio 0.5 · Tensile Strength (Ultimate) 12 MPa1.7 ksi · Hardness, Shore A 70 Shore A · Hardness, Shore D 22 Shore D · Tear Strength 25 kN/m143 lbf/in
Physical
Density and transition temperatures.
Density
Glass Transition (Tg)
Water Absorption (24 h)
Water Absorption (Saturation)
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Max Service Temperature (continuous)
Min Service Temperature
Limiting Oxygen Index
Max Service Temperature (short-term)
Same in both: Thermal Expansion (CTE, 20–100 °C) 180 µm/m·K100 µin/in·°F
Electrical
Conductivity and insulation.
Electrical Resistivity
Dielectric Strength
Dielectric Constant (1 MHz)
Volume Resistivity
Dissipation Factor (1 MHz)
Comparative Tracking Index (CTI)
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
UV / Weathering Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Formability (cold)
Mold Shrinkage
Mold Temperature (typ.)
Polishability
Processing Melt Temperature (typ.)
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Typical Recycled Content
Embodied Water
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Thermal Shock Resistance Index
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.
Manufacturing and finishing
| Capability | ECO | EPDM |
|---|---|---|
| Injection molding | — | Yes |
| Default condition | — | Solid |
| Relative cost | $$$$ High | $$ 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 |
ECO vs EPDM — frequently asked
What is the difference between ECO and EPDM?
ECO and EPDM are both polymer grades. EPDM is the more ductile: elongation 400% versus 250% for ECO. EPDM is lighter (1.15 g/cm³ vs 1.36 g/cm³ for ECO) and EPDM conducts heat better (0.3 W/m·K vs 0.22 W/m·K).
Which is cheaper, ECO or EPDM?
EPDM is the lower-cost material: it sits in the standard tier ($$) while ECO is high ($$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.
Which is easier to machine, ECO or EPDM?
EPDM, by a small margin. Both rate poor for machinability — 30/100 against 25/100 for ECO; for welding the order is EPDM first (poor, 15/100) then ECO (not recommended, 10/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in ECO and EPDM 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.