PEKK-ESD vs PI
Polymer · grade comparison
PEKK-ESD and PI are both polymer grades, both high performance plastic. PI is the more ductile: elongation 7.5% versus 3% for PEKK-ESD. PEKK-ESD is lighter (1.33 g/cm³ vs 1.43 g/cm³ for PI) and PEKK-ESD is stiffer (3.5 GPa vs 3 GPa). On the shop floor, PEKK-ESD welds better (poor vs not recommended).
PEKK-ESDChoose it when weight is the constraint, or when it will be welded.
PIChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
PEKK-ESD vs PI: 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
Shear Modulus
Poisson's Ratio
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Compressive Strength
Compressive Modulus
Flexural Strength
Flexural Modulus
Shear Strength
Fracture Toughness (K_IC)
Izod Impact, Notched
Hardness, Shore D
Hardness, Rockwell M
Hardness, Rockwell R
Bulk Modulus
Physical
Density and transition temperatures.
Density
Melting Temperature (Tm)
Glass Transition (Tg)
Water Absorption (24 h)
Water Absorption (Saturation)
Refractive Index
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
Vicat Softening Point (B50)
Limiting Oxygen Index
Max Service Temperature (short-term)
Electrical
Conductivity and insulation.
Electrical Resistivity
Volume Resistivity
Surface Resistivity
Dielectric Strength
Dielectric Constant (1 MHz)
Dissipation Factor (1 MHz)
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)
Polishability
Mold Shrinkage
Melt Flow Rate
Processing Melt Temperature (typ.)
Mold Temperature (typ.)
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Same in both: Embodied Water 600 L/kg71.9 gal/lb · 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 | PEKK-ESD | PI |
|---|---|---|
| 3D printing | Yes | — |
| CNC machining | — | Yes |
| Sheet metal | — | Yes |
| Injection molding | — | Yes |
| Default condition | — | Unfilled |
| Relative cost | $$$$$ Specialty | $$$$$ Specialty |
| Min. machined wall | — | 0.5 mm |
| Best machined surface | — | Ra 0.8 µm |
| Chrome Plating (Plastic) | — | Yes |
| Conductive Coating | Yes | — |
| Dyeing (Nylon) | Yes | — |
| Primer Coating | Yes | — |
| Spray Painting | — | Yes |
| Tinted Coating | Yes | — |
| Vacuum Metallization | Yes | — |
| Waterproof Coating | Yes | — |
They share 4 finishes: EMI Shielding Coating, Painting, Soft Touch Coating, UV Coating.
PEKK-ESD vs PI — frequently asked
What is the difference between PEKK-ESD and PI?
PEKK-ESD and PI are both polymer grades, both high performance plastic. PI is the more ductile: elongation 7.5% versus 3% for PEKK-ESD. PEKK-ESD is lighter (1.33 g/cm³ vs 1.43 g/cm³ for PI) and PEKK-ESD is stiffer (3.5 GPa vs 3 GPa).
Which is cheaper, PEKK-ESD or PI?
Both sit in the same relative cost tier ($$$$$, specialty); the part price will be decided by machining time, tolerance and quantity rather than by the material.
Which welds better, PEKK-ESD or PI?
PEKK-ESD. Its weldability rates poor (30/100) against not recommended (5/100) for PI.
Ready to make it?
Upload a CAD file and FabDigit prices the part in PEKK-ESD and PI 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.