Comparison

PEEK vs PETG

A side-by-side comparison of Polyether Ether Ketone and Polyethylene Terephthalate Glycol.

Property
PEEK
PETG

Physical

Density
1.32 g/cm³
1.27 g/cm³
Water Absorption (24h)
0.15 %
0.13 %
Transparency
Opaque (amber)
Transparent
Shrinkage
1.1 – 1.4 %
0.2 – 0.5 %

Mechanical

Young's Modulus
3.6 GPa
2.1 GPa
Tensile Strength
100 MPa
50 MPa
Flexural Strength
170 MPa
70 MPa
Impact Strength (Izod)
55 J/m
100 J/m
Elongation at Break
50 %
120 %

Thermal

Melting Point
343 °C
Glass Transition Temperature
143 °C
80 °C
Continuous Service Temperature
260 °C
65 °C
Heat Deflection Temperature
160 °C
70 °C
CTE
68 × 10⁻⁶ /K

Electrical

Dielectric Constant
3.2
3.3
Volume Resistivity
10¹⁶ Ω·cm
10¹⁴ Ω·cm

Chemical resistance

Acids
Excellent
Good
Bases
Excellent
Fair
Solvents
Excellent
Hydrolysis (steam)
Excellent
UV Resistance
Fair
Fair
Alcohols
Good
Oils
Good

Sustainability

Recyclability
Recyclable (specialty)
Recyclable
Recycling Code
7
1
Carbon Footprint
~30 kg CO₂e / kg
~2.7 kg CO₂e / kg
Bio-based Content
0 %