Comparison
HDPE vs PLA
A side-by-side comparison of High-Density Polyethylene and Polylactic Acid.
Physical
Density
0.95 g/cm³
1.24 g/cm³
Water Absorption (24h)
< 0.01 %
0.5 %
Transparency
Translucent to opaque
Semi-transparent
Shrinkage
1.5 – 3.0 %
0.3 – 0.5 %
Mechanical
Young's Modulus
1.1 GPa
3.5 GPa
Tensile Strength
25 – 35 MPa
50 – 65 MPa
Impact Strength
No break
—
Elongation at Break
500 – 1000 %
6 %
Flexural Strength
—
80 MPa
Impact Strength (Izod)
—
16 J/m
Thermal
Melting Point
130 °C
150 – 160 °C
Continuous Service Temperature
80 °C
45 °C
Heat Deflection Temperature
75 °C
55 °C
Glass Transition Temperature
—
60 °C
Electrical
Dielectric Constant
2.3
3.0
Volume Resistivity
10¹⁶ Ω·cm
10¹⁴ Ω·cm
Chemical resistance
Acids
Excellent
Fair
Bases
Excellent
Poor
Alcohols
Excellent
Fair
Oils
Good
—
UV Resistance
Poor unless stabilized
Poor
Hydrolysis
—
Poor
Sustainability
Recyclability
Widely recycled
Industrially compostable
Recycling Code
2
7
Bio-based Content
0 – 100 %
100 %
Carbon Footprint
~1.9 kg CO₂e / kg
~1.6 kg CO₂e / kg