Comparison
Cellulose Acetate Film Grade K vs PETG
A side-by-side comparison of Cellulose Acetate, Film Grade K and Polyethylene Terephthalate Glycol.
Physical
Density
1.30 g/cm³
1.27 g/cm³
Water Absorption (24h)
2.0 %
0.13 %
Transparency
Excellent
Transparent
Shrinkage
1.0 - 2.0 %
0.2 – 0.5 %
Mechanical
Young's Modulus
2.5 GPa
2.1 GPa
Tensile Strength
40 MPa
50 MPa
Elongation at Break
15.0 %
120 %
Impact Strength (Izod)
0.5 J/cm
100 J/m
Flexural Strength
—
70 MPa
Thermal
Glass Transition Temperature
100-120 °C
80 °C
Melting Point
None (degrades)
—
Continuous Service Temperature
60 °C
65 °C
Heat Deflection Temperature
60 °C
70 °C
CTE
—
68 × 10⁻⁶ /K
Electrical
Dielectric Constant
3.5
3.3
Volume Resistivity
10¹⁰ Ω·cm
10¹⁴ Ω·cm
Dielectric Strength
15 kV/mm
—
Chemical resistance
Acids
Poor resistance
Good
Bases
Poor resistance
Fair
Solvents
Soluble in esters, ketones, and chlorinated hydrocarbons
—
UV Resistance
Moderate
Fair
Alcohols
—
Good
Oils
—
Good
Sustainability
Recyclability
Biodegradable (compost, requires specific conditions)
Recyclable
Recycling Code
7 (Other)
1
Carbon Footprint
Moderate
~2.7 kg CO₂e / kg
Bio-based Content
—
0 %