Properties
Propylene oxide is a colorless, low-boiling, highly volatile liquid with a sweet, ether-like odor. It is flammable and reactive, so storage and unloading areas must be specifically designed and monitored. Dow offers technical and product stewardship support by way of periodic safe handling and storage reviews, and training.
Use the table below to locate property information for propylene oxide.
| Chemical Name |
1,2 epoxypropane |
| Synonyms |
2-methyloxirane
1,2-propylene oxide
methyl ethylene oxide |
| Formula |
C3H6O |
| Molecular Weight (g/mol) |
58.08 |
| CAS Number |
000075-56-9 |
| EINECS Number |
200-879-2 |
| Density 25°C (77°F) |
0.821 g/cm3 (6.861 lb./gal) |
| Vapor Density (Air = 1.0) |
2.0 |
| Vapor Pressure, 25°C (77°F) |
71.7 kPa (538 mm Hg) |
| Freezing Point |
-111.93°C (-169.47°F) |
| Boiling Point, 101.3 kPa |
34.2°C (93.56°F) |
| Specific Gravity, 25/25°C (77°F) |
0.8253 |
| Refractive Index n20/D°C (68°F) |
1.36610 |
| n25/D°C (77°F) |
1.36335 |
| Viscosity, 25°C (77°F) |
0.305 centipoise |
| Specific Heat, 0°C (32°F) |
2.08 J/(g°K) (0.5 Btu/lb/°F) |
| Auto-Ignition Temperature, in Air, 101.3 kPa |
449°C (840.2°F) |
| Explosive limits in air, 25°C, 101.3 kPa |
2.3 – 37.0 vol % |
| Flash Point, TAG-Closed cup |
-37.2°C (-35°F) |
| Heat of Combustion, 25°C, 101.3 kPa |
-33035 kJ/kg |
| Heat of Vaporization, 101.3 kPa |
465.7 kJ/kg |
| Solubility in water, at 20°C (68°F) |
40.5 wt % |
| Solubility of water in propylene oxide at 20°C |
14.7 wt % |
For Propylene Oxide Safety Data Sheets, Technical Data Sheets and other technical documents, please go to Technical Information.
