Properties of Isotactic Polypropylene (PP)
Isotactic polypropylene (PP) is a widely used thermoplastic polymer known for its high strength, rigidity, and excellent chemical resistance. It features a uniform molecular structure, with all methyl groups aligned on the same side of the polymer chain, which enhances its crystallinity and mechanical performance.
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The following table provides a comprehensive list of isotactic polypropylene (PP) properties in both SI and US customary/Imperial units at normal temperature and pressure (NTP).
Click on the button to switch between Metric and Imperial units.
| Physical Properties | Metric |
|---|---|
| Category | Thermoplastic |
| Density | 920 - 940 kg/m3 |
| Water Absorption | 0.01 %wt/day |
| Mechanical Properties | Metric |
| Ultimate Tensile Strength | 31 - 41 MPa |
| Young’s Modulus (E) | 0.69 - 1.52 GPa |
| Flexural Modulus | 1.2 - 1.7 GPa |
| Elongation at Break | 100 - 600% |
| Rockwell Hardness (R) | 95 |
| Thermal Properties | Metric |
| Melting Point | 165 °C |
| Thermal Conductivity | 0.154 W/m·K |
| Specific Heat Capacity (Cp) | 1960 J/kg·K |
| Coefficient of Thermal Expansion (αL) | 8.1×10-5 - 10-4 1/°C |
| Glass Transition Temperature (Tg) | -10 to -1.5 °C |
| Electrical Properties | Metric |
| Relative Permittivity (@1 MHz) (εr) | 2.2 - 2.3 |
| Electrical Resistivity | 1016 Ω·cm |
| Dielectric Field Strength (Ed) | 200 - 260 kV/cm |
| Hazardous Data | Metric |
| Flammability Rating (ANSI/UL 94) | Combustible |
Unless stated otherwise, all values are taken at room temperature (approximately 20°C or 68°F) and 1 atm pressure. (1 atm = 101,325 Pa)