Unfilled PP Homopolymer
Unfilled PP homopolymer is a grade of PP homopolymer. It has the lowest strength and highest ductility compared to the other variants of PP homopolymer. The graph bars on the material properties cards below compare unfilled PP homopolymer to: polypropylene 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
Compressive (Crushing) Strength
45 MPa 6.5 x 103 psi
Elastic (Young's, Tensile) Modulus
1.4 GPa 0.2 x 106 psi
Elongation at Break
80 %
Flexural Modulus
1.5 GPa 0.22 x 106 psi
Flexural Strength
41 MPa 5.9 x 103 psi
Impact Strength: Notched Izod
42 J/m 0.79 ft-lb/in
Rockwell R Hardness
90
Tensile Strength: Ultimate (UTS)
36 MPa 5.1 x 103 psi
Thermal Properties
Glass Transition Temperature
170 °C 340 °F
Heat Deflection Temperature At 1.82 MPa (264 psi)
73 °C 160 °F
Heat Deflection Temperature At 455 kPa (66 psi)
110 °C 220 °F
Maximum Temperature: Autoignition
370 °C 700 °F
Maximum Temperature: Decomposition
350 °C 660 °F
Maximum Temperature: Mechanical
120 °C 250 °F
Melting Onset (Solidus)
160 °C 320 °F
Specific Heat Capacity
1900 J/kg-K 0.45 BTU/lb-°F
Thermal Conductivity
0.15 W/m-K 0.087 BTU/h-ft-°F
Thermal Expansion
90 µm/m-K
Electrical Properties
Dielectric Constant (Relative Permittivity) At 1 Hz
2.2
Dielectric Strength (Breakdown Potential)
26 kV/mm 1.0 V/mil
Otherwise Unclassified Properties
Density
0.91 g/cm3 56 lb/ft3
Limiting Oxygen Index (LOI)
17 %
Water Absorption After 24 Hours
0.010 %
Water Absorption At Saturation
0.010 %
Common Calculations
Stiffness to Weight: Axial
0.86 points
Stiffness to Weight: Bending
41 points
Strength to Weight: Axial
11 points
Strength to Weight: Bending
27 points
Thermal Diffusivity
0.087 mm2/s
Thermal Shock Resistance
20 points
Followup Questions
Further Reading
ASTM D883: Standard Terminology Relating to Plastics
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