Cyanate Ester vs Epoxy
Polymer · grade comparison
Cyanate Ester and Epoxy are both polymer grades. Cyanate Ester is the stronger of the two: tensile strength 80 MPa (11.6 ksi) against 65 MPa (9.43 ksi) for Epoxy, about 23% more. In exchange, Epoxy is the more ductile: elongation 4% versus 2.6% for Cyanate Ester. Cyanate Ester runs hotter in service (200°C vs 130°C continuous) and Cyanate Ester conducts heat better (0.24 W/m·K vs 0.2 W/m·K). On the shop floor, Epoxy sits in a lower cost tier (standard, $$) than Cyanate Ester (high, $$$$).
Cyanate EsterChoose it when strength drives the design, or when the part sees heat.
EpoxyChoose it when the part is bent, formed or impact-loaded, or when cost is the deciding factor.
Cyanate Ester vs Epoxy: 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.
Elastic (Young's) Modulus
Bulk Modulus
Tensile Strength (Ultimate)
Elongation at Break
Compressive Strength
Compressive Modulus
Flexural Strength
Flexural Modulus
Shear Strength
Hardness, Shore D
Hardness, Rockwell M
Same in both: Shear Modulus 1.2 GPa0.17 Msi · Poisson's Ratio 0.35 · Fracture Toughness (K_IC) 0.6 MPa·√m0.55 ksi·√in · Izod Impact, Notched 20 J/m0.37 ft·lbf/in
Physical
Density and transition temperatures.
Density
Glass Transition (Tg)
Water Absorption (24 h)
Water Absorption (Saturation)
Refractive Index
Light Transmission
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Max Service Temperature (continuous)
Min Service Temperature
Heat Deflection Temp. @ 0.45 MPa
Heat Deflection Temp. @ 1.8 MPa
Limiting Oxygen Index
Max Service Temperature (short-term)
Electrical
Conductivity and insulation.
Electrical Resistivity
Dielectric Strength
Dielectric Constant (1 MHz)
Dissipation Factor (1 MHz)
Volume Resistivity
Surface Resistivity
Comparative Tracking Index (CTI)
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
UV / Weathering Resistance
Same in both: Corrosion Resistance 82 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Polishability
Mold Shrinkage
Processing Melt Temperature (typ.)
Mold Temperature (typ.)
Same in both: Machinability 55 / 100 · Weldability 0 / 100 · Formability (cold) 5 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Same in both: Typical Recycled Content 0%
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Same in both: Thermal Diffusivity 0.2 mm²/s · Thermal Shock Resistance Index 0
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 | Cyanate Ester | Epoxy |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$$ High | $$ Standard |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Cyanate Ester vs Epoxy — frequently asked
Is Cyanate Ester stronger than Epoxy?
Yes. Cyanate Ester has a typical tensile strength of 80 MPa (11.6 ksi) against 65 MPa (9.43 ksi) for Epoxy — about 23% more.
Which is cheaper, Cyanate Ester or Epoxy?
Epoxy is the lower-cost material: it sits in the standard tier ($$) while Cyanate Ester is high ($$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.
When should I choose Cyanate Ester over Epoxy?
Pick Cyanate Ester when strength drives the design, or when the part sees heat. Pick Epoxy when the part is bent, formed or impact-loaded, or when cost is the deciding factor.
Ready to make it?
Upload a CAD file and FabDigit prices the part in Cyanate Ester and Epoxy 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.