Comparison
Casein Bioplastic vs PETG
A side-by-side comparison of Casein, Bioplastic Grade U and Polyethylene Terephthalate Glycol.
Physical
Density
1.30-1.40 g/cm³
1.27 g/cm³
Water Absorption (24h)
3.0-6.0 %
0.13 %
Transparency
Opaque
Transparent
Shrinkage
2.0 - 4.0 %
0.2 – 0.5 %
Mechanical
Young's Modulus
2.0-3.0 GPa
2.1 GPa
Tensile Strength
25-40 MPa
50 MPa
Elongation at Break
3.0 %
120 %
Impact Strength (Izod)
0.1 J/cm
100 J/m
Flexural Strength
—
70 MPa
Thermal
Glass Transition Temperature
70-90 °C
80 °C
Melting Point
None (degrades)
—
Continuous Service Temperature
50 °C
65 °C
Heat Deflection Temperature
45 °C
70 °C
CTE
—
68 × 10⁻⁶ /K
Electrical
Dielectric Constant
5.5
3.3
Volume Resistivity
10⁸ Ω·cm
10¹⁴ Ω·cm
Dielectric Strength
10 kV/mm
—
Chemical resistance
Acids
Sensitive
Good
Bases
Sensitive
Fair
Solvents
Insoluble in water, but sensitive to moisture; soluble in alkaline solutions
—
UV Resistance
Poor
Fair
Alcohols
—
Good
Oils
—
Good
Sustainability
Recyclability
Biodegradable (compost)
Recyclable
Recycling Code
7 (Other)
1
Carbon Footprint
Low (utilizes dairy byproduct)
~2.7 kg CO₂e / kg
Bio-based Content
—
0 %