Propylene oxide
Description
Propylene oxide (CAS 75-56-9), commonly abbreviated as PO, is a reactive epoxide monomer and industrial solvent used across polymer manufacturing, sterilization, and chemical synthesis.
Methyl oxirane is the form referenced in many technical and regulatory contexts as a distinct search term. Its primary commercial role is as a building block for polyols and propylene glycols.
PO is the key feedstock for polyether polyols used in polyurethane foam production. This covers rigid insulation panels, flexible seating, and various automotive interiors for industrial manufacturing.
In food and pharmaceutical processing, it functions as a fumigant and sterilizing agent for spices and cocoa. It is also used for medical equipment where heat sterilization is not viable.
Propylene glycol, produced by hydration of PO, feeds into food-grade humectants and cosmetic carriers. It is also a primary component in modern antifreeze formulations and industrial coolants.
In biotechnology, PO is used as a fixative and dehydration agent in electron microscopy sample preparation. It is supplied as a liquid in bulk quantities, typically via ISO tank containers.
Standard commercial grades include polymer-grade and technical-grade specifications. Purity levels are commonly at 99.5% or higher for polyol synthesis applications and chemical manufacturing.
Buyers sourcing for food or pharmaceutical sterilization applications should confirm compliance with regional regulatory standards. Proper handling is required due to its low boiling point and volatility.
Physical Properties
| Melting Point | -112.13 °C |
| Boiling Point | 34.23 °C |
| Density | 0.8 g/cm³ |
| Flash Point | −35 °F |
| Appearance | Propylene oxide is a colorless liquid. Ethereal odor. |
| Color | Clear |
| Odor | Ethereal; characteristic; sweet, alcoholyc; like natural gas. |
| Form | Liquid |
| Water Solubility | 40 g/100 mL (20 ºC) |
| Vapor Pressure | 29.43 psi ( 55 °C) |
| Refractive Index | n 20/D 1.366(lit.) |
| Log P | 0.030 |
Safety & Handling (Learn More)
Trade & Regulatory
| HS Code | 29102000 |
| UN Number | 1280 |
| ADR Class | 3 |
| Packing Group | I |
| Storage Class | 3 - Flammable liquids |
| WGK (Germany) | 3 |
Documentation
Other Names
propene oxide|methyl oxirane|methyl ethylene oxide|2,3-epoxypropane|1,2-propylene oxide|1,2-epoxy propane|2-methyloxirane|Oxirane, methyl-|PO
Related Products
Need a chemical? Get a quote within 24 hours.