Comparison
SMC/BMC for Automotive vs PLA
A side-by-side comparison of Sheet Molding Compound / Bulk Molding Compound and Polylactic Acid.
Physical
Density
1.60-1.90 g/cm³
1.24 g/cm³
Water Absorption (24h)
0.1-0.5 %
0.5 %
Transparency
Opaque
Semi-transparent
Shrinkage
0.5-1.5 %
0.3 – 0.5 %
Mechanical
Young's Modulus
10-20 GPa
3.5 GPa
Tensile Strength
80-150 MPa
50 – 65 MPa
Elongation at Break
1-3 %
6 %
Impact Strength (Izod)
20-50 J/m
16 J/m
Flexural Strength
—
80 MPa
Thermal
Glass Transition Temperature
80-120 °C
60 °C
Melting Point
N/A
150 – 160 °C
Continuous Service Temperature
100-150 °C
45 °C
Heat Deflection Temperature
80-120 °C
55 °C
Electrical
Dielectric Constant
4.5-6.0
3.0
Volume Resistivity
10^12-10^14 Ohm-cm
10¹⁴ Ω·cm
Dielectric Strength
15-25 kV/mm
—
Chemical resistance
Acids
Good resistance
Fair
Bases
Moderate resistance
Poor
Solvents
Good resistance to hydrocarbons
—
UV Resistance
Moderate without additives
Poor
Alcohols
—
Fair
Hydrolysis
—
Poor
Sustainability
Recyclability
Difficult
Industrially compostable
Recycling Code
N/A
7
Carbon Footprint
Moderate
~1.6 kg CO₂e / kg
Bio-based Content
—
100 %