Comparison
HDPE Injection Molding vs PETG
A side-by-side comparison of High-Density Polyethylene for Injection Molding and Polyethylene Terephthalate Glycol.
Physical
Density
0.941-0.965 g/cm³
1.27 g/cm³
Water Absorption (24h)
<0.05 %
0.13 %
Transparency
Opaque
Transparent
Shrinkage
1.5-3 %
0.2 – 0.5 %
Mechanical
Young's Modulus
0.8-1.5 GPa
2.1 GPa
Tensile Strength
20-35 MPa
50 MPa
Elongation at Break
50-300 %
120 %
Impact Strength (Izod)
No Break
100 J/m
Flexural Strength
—
70 MPa
Thermal
Glass Transition Temperature
-120 °C
80 °C
Melting Point
125-135 °C
—
Continuous Service Temperature
80-100 °C
65 °C
Heat Deflection Temperature
50-65 °C
70 °C
CTE
—
68 × 10⁻⁶ /K
Electrical
Dielectric Constant
2.25-2.35
3.3
Volume Resistivity
>10¹⁵ Ω⋅cm
10¹⁴ Ω·cm
Dielectric Strength
15-25 kV/mm
—
Chemical resistance
Acids
Excellent resistance
Good
Bases
Excellent resistance
Fair
Solvents
Good resistance at room temperature, swells in hot aromatic hydrocarbons
—
UV Resistance
Poor (requires stabilization)
Fair
Alcohols
—
Good
Oils
—
Good
Sustainability
Recyclability
Recyclable
Recyclable
Recycling Code
2 (PE-HD)
1
Carbon Footprint
Moderate
~2.7 kg CO₂e / kg
Bio-based Content
—
0 %