Comparison
High-Temperature Sealant Silicone Rubber vs PEEK
A side-by-side comparison of High-Temperature Sealant Grade Vinyl Methyl Silicone Rubber (VMQ) and Polyether Ether Ketone.
Physical
Density
1.14 - 1.20 g/cm³
1.32 g/cm³
Water Absorption (24h)
0.2 - 0.4 %
0.15 %
Transparency
Opaque
Opaque (amber)
Shrinkage
1.5 - 2.5 %
1.1 – 1.4 %
Mechanical
Young's Modulus
0.001 - 0.008 GPa
3.6 GPa
Tensile Strength
4 - 8 MPa
100 MPa
Elongation at Break
300 - 600 %
50 %
Impact Strength (Izod)
N/A
55 J/m
Flexural Strength
—
170 MPa
Thermal
Glass Transition Temperature
-70 to -50 °C
143 °C
Melting Point
N/A
343 °C
Continuous Service Temperature
-50 to 250 °C
260 °C
Heat Deflection Temperature
N/A
160 °C
Electrical
Dielectric Constant
2.9 - 3.1
3.2
Volume Resistivity
10^13 - 10^15 Ohm-cm
10¹⁶ Ω·cm
Dielectric Strength
18 - 28 kV/mm
—
Chemical resistance
Acids
Poor
Excellent
Bases
Poor
Excellent
Solvents
Poor resistance to hydrocarbon solvents
Excellent
UV Resistance
Excellent
Fair
Hydrolysis (steam)
—
Excellent
Sustainability
Recyclability
Very Limited
Recyclable (specialty)
Recycling Code
N/A
7
Carbon Footprint
High
~30 kg CO₂e / kg