Polyphenylene Oxide (PPO)
PPO is a thermoplastic, further classified as a polyphenylene plastic.
The properties of PPO include three common variations. This page shows summary ranges across all of them. For more specific values, follow the links immediately below. The graph bars on the material properties cards further below compare PPO to: polyphenylene plastics (top), all thermoplastics (middle), and the entire database (bottom). A full bar means this is the highest value in the relevant set. A half-full bar means it's 50% of the highest, and so on.
Mechanical Properties
Elongation at Break
3.5 to 28 %
Flexural Modulus
2.5 to 8.6 GPa 0.37 to 1.2 x 106 psi
Flexural Strength
92 to 140 MPa 13 to 20 x 103 psi
Impact Strength: Notched Izod
80 to 270 J/m 1.5 to 5.0 ft-lb/in
Tensile Strength: Ultimate (UTS)
63 to 140 MPa 9.1 to 20 x 103 psi
Thermal Properties
Heat Deflection Temperature At 1.82 MPa (264 psi)
120 to 140 °C 260 to 280 °F
Maximum Temperature: Mechanical
100 to 110 °C 220 °F
Specific Heat Capacity
1020 to 1250 J/kg-K 0.24 to 0.3 BTU/lb-°F
Thermal Expansion
25 to 60 µm/m-K
Electrical Properties
Dielectric Constant (Relative Permittivity) At 1 Hz
2.7 to 3.2
Dielectric Strength (Breakdown Potential)
19 to 21 kV/mm 0.74 to 0.82 V/mil
Electrical Dissipation At 1 Hz
0.0010 to 0.0020
Electrical Resistivity Order of Magnitude
15 10x Ω-m
Otherwise Unclassified Properties
Density
1.1 to 1.4 g/cm3 67 to 87 lb/ft3
Limiting Oxygen Index (LOI)
32 %
Water Absorption After 24 Hours
0.060 to 0.070 %
Common Calculations
Strength to Weight: Axial
16 to 27 points
Strength to Weight: Bending
33 to 42 points
Followup Questions
Further Reading
Reinforced Plastics Durability, Geoffrey Pritchard (editor), 1999
SPI Plastics Engineering Handbook of the Society of the Plastics Industry, Inc., 5th ed., Michael L. Berins (editor), 2000
Modern Plastics Handbook, Charles A. Harper (editor), 1999
Plastics Materials, 7th ed., J. A. Brydson, 1999
CRC Materials Science and Engineering Handbook, 4th ed., James F. Shackelford et al. (editors), 2015