Comparison

PETG vs PEEK

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

Property

PETG

PEEK

Physical

Density

1.27 g/cm³

1.32 g/cm³

Water Absorption (24h)

0.13 %

0.15 %

Transparency

Transparent

Opaque (amber)

Shrinkage

0.2 – 0.5 %

1.1 – 1.4 %

Mechanical

Young's Modulus

2.1 GPa

3.6 GPa

Tensile Strength

50 MPa

100 MPa

Flexural Strength

70 MPa

170 MPa

Impact Strength (Izod)

100 J/m

55 J/m

Elongation at Break

120 %

50 %

Thermal

Glass Transition Temperature

80 °C

143 °C

Heat Deflection Temperature

70 °C

160 °C

Continuous Service Temperature

65 °C

260 °C

CTE

68 × 10⁻⁶ /K

—

Melting Point

—

343 °C

Electrical

Dielectric Constant

3.3

3.2

Volume Resistivity

10¹⁴ Ω·cm

10¹⁶ Ω·cm

Chemical resistance

Acids

Good

Excellent

Bases

Fair

Excellent

Alcohols

Good

—

Oils

Good

—

UV Resistance

Fair

Solvents

—

Excellent

Hydrolysis (steam)

—

Excellent

Sustainability

Recyclability

Recyclable

Recyclable (specialty)

Recycling Code

Bio-based Content

0 %

—

Carbon Footprint

~2.7 kg CO₂e / kg

~30 kg CO₂e / kg