Comparison
GPPS Sheet Extrusion vs PLA
A side-by-side comparison of General Purpose Polystyrene for Sheet Extrusion and Polylactic Acid.
Physical
Density
1.04-1.06 g/cm³
1.24 g/cm³
Water Absorption (24h)
0.03-0.1 %
0.5 %
Transparency
Excellent
Semi-transparent
Shrinkage
0.4-0.8 %
0.3 – 0.5 %
Mechanical
Young's Modulus
3.0-3.5 GPa
3.5 GPa
Tensile Strength
45-60 MPa
50 – 65 MPa
Elongation at Break
2-5 %
6 %
Impact Strength (Izod)
10-20 J/m
16 J/m
Flexural Strength
—
80 MPa
Thermal
Glass Transition Temperature
90-100 °C
60 °C
Melting Point
N/A (amorphous)
150 – 160 °C
Continuous Service Temperature
60-70 °C
45 °C
Heat Deflection Temperature
70-80 °C
55 °C
Electrical
Dielectric Constant
2.5-2.6
3.0
Volume Resistivity
10¹⁵-10¹⁶ Ω⋅cm
10¹⁴ Ω·cm
Dielectric Strength
15-25 kV/mm
—
Chemical resistance
Acids
Good resistance
Fair
Bases
Good resistance
Poor
Solvents
Attacked by aromatic hydrocarbons, ketones, and esters
—
UV Resistance
Poor
Poor
Alcohols
—
Fair
Hydrolysis
—
Poor
Sustainability
Recyclability
Recyclable
Industrially compostable
Recycling Code
6 (PS)
7
Carbon Footprint
Moderate
~1.6 kg CO₂e / kg
Bio-based Content
—
100 %