Substance profile
Styrene Oxide
Styrene Oxide is a colorless to pale straw-colored liquid with a sweet, pleasant odor.
01 · Identification
What Styrene Oxide is
Styrene Oxide is a colorless to pale straw-colored liquid with a sweet, pleasant odor. Its molecular formula is C8H8O and its molecular weight is 120.15 g/mol. It boils at 194 °C, melts at -35.6 °C.
Under the GHS it carries the signal word Danger. It is classed as hazardous Air Pollutants (HAPs).
Other names for Styrene Oxide
- (epoxyethyl)benzene
- phenyloxirane
02 · GHS classification
Hazards and label elements
Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.
| Code | Hazard statement |
|---|---|
| H350 | May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>. |
| H312 | Harmful in contact with skin. |
| H319 | Causes serious eye irritation. |
Precautionary statements: P201, P264, P280, P302, P305, P308, P312, P313, P337, P338, P352
03 · Physical and chemical properties
Styrene Oxide properties
Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.
| Property | Value | Conditions | Source |
|---|---|---|---|
| Boiling point | 194.1 °C (381.4 °F) | HSDB | |
| 193.89 °C (381 °F) | at 760 mmHg | CAMEO | |
| 194 °C (381.2 °F) | ICSC | ||
| Melting point | -35.6 °C (-32.1 °F) | HSDB | |
| -37.22 °C (-35 °F) | CAMEO | ||
| -36.7 °C (-34.1 °F) | ICSC | ||
| Density | 1.05 g/cm³ | ICSC | |
| 1.0523 g/cm³ | OSHA | ||
| 1.049 g/cm³ | at 25 °C | HSDB | |
| Solubility | Completely soluble in acetone, benzene, carbon tetrachloride, ethyl ether, heptane, methanol | HSDB | |
| 0.3% wt in water | HSDB | ||
| less than 1 mg/mL at 67.1 °F (NTP, 1992) | at 19.5 °C | CAMEO | |
| Vapor pressure | 0.3 mmHg | at 20 °C | HSDB |
| Flash point | 73.89 °C (165 °F) | HSDB | |
| 79.44 °C (175 °F) | CAMEO | ||
| 76 °C (168.8 °F) | ICSC | ||
| Autoignition temperature | 498.33 °C (929 °F) | HSDB | |
| 498 °C (928.4 °F) | ICSC | ||
| Lower explosive limit (LEL) | 1.1 % by volume | ICSC | |
| Upper explosive limit (UEL) | 22 % by volume | ICSC | |
| Vapor density | 4.3 (air = 1) | HSDB | |
| 4.14 (air = 1) | CAMEO | ||
| Odor threshold | Odor detection in air, 0.063 ppm (purity not specified) | HSDB | |
| Odor recognition in air, 0.400 ppm (purity not specified) | HSDB | ||
| Odor low 0.3093 mg/cu m; Odor high 1.9640 mg/cu m | HSDB |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
04 · Handling and storage
Storing and handling Styrene Oxide
Storage conditions
... PRECAUTIONS SHOULD BE TAKEN TO PREVENT EXCESSIVE PRESSURE UNDER STORAGE OR REACTION CONDITIONS & TO RELIEVE SUCH PRESSURE SHOULD IT OCCUR.
Source: Hazardous Substances Data Bank (HSDB)
Incompatible materials
REACTS VIGOROUSLY WITH CMPD HAVING LABILE HYDROGEN, INCL WATER, IN PRESENCE OF CATALYSTS SUCH AS ACIDS, BASES, & CERTAIN SALTS
Source: Hazardous Substances Data Bank (HSDB)
Reactivity
STYRENE OXIDE is incompatible with oxidizing agents. Also incompatible with acids and bases. Reacts with 4-(4'-nitrobenzyl)pyridine. Polymerizes exothermally and reacts vigorously with compounds possessing a labile hydrogen (e.g. alcohols and amines) in the presence of catalysts such as acids, bases and certain salts (NTP, 1992).
Source: CAMEO Chemicals
Planning storage for a mix of chemicals? Check Styrene Oxide in the storage compatibility matrix →