Comparison
EPP Automotive vs PEEK
A side-by-side comparison of Expanded Polypropylene for Automotive Applications and Polyether Ether Ketone.
Physical
Density
0.03-0.1 g/cm³ (foam)
1.32 g/cm³
Water Absorption (24h)
<1 %
0.15 %
Transparency
Opaque
Opaque (amber)
Shrinkage
N/A (foam)
1.1 – 1.4 %
Mechanical
Young's Modulus
Highly variable (foam)
3.6 GPa
Tensile Strength
Highly variable (foam)
100 MPa
Elongation at Break
Highly variable (foam)
50 %
Impact Strength (Izod)
Excellent energy absorption
55 J/m
Flexural Strength
—
170 MPa
Thermal
Glass Transition Temperature
N/A (amorphous)
143 °C
Melting Point
160-165 °C (solid PP)
343 °C
Continuous Service Temperature
90-110 °C
260 °C
Heat Deflection Temperature
N/A (foam)
160 °C
Electrical
Dielectric Constant
Around 1.5 (foam)
3.2
Volume Resistivity
>10¹³ Ω⋅cm (foam)
10¹⁶ Ω·cm
Dielectric Strength
High (foam)
—
Chemical resistance
Acids
Good resistance
Excellent
Bases
Good resistance
Excellent
Solvents
Good resistance
Excellent
UV Resistance
Poor (requires stabilization)
Fair
Hydrolysis (steam)
—
Excellent
Sustainability
Recyclability
Recyclable
Recyclable (specialty)
Recycling Code
5 (PP)
7
Carbon Footprint
Moderate
~30 kg CO₂e / kg