Substance profile
Diketene
Diketene is a colorless liquid; turns brownish-yellow upon standing at room temperature with a pungent odor.
01 · Identification
What Diketene is
Diketene is a colorless liquid; turns brownish-yellow upon standing at room temperature with a pungent odor. Its molecular formula is C4H4O2 and its molecular weight is 84.07 g/mol. It boils at 127 °C, melts at -6.5 °C.
Under the GHS it carries the signal word Warning. It is classed as flammable agents - 3rd degree.
Other names for Diketene
- diketen
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 |
|---|---|
| H226 | Flammable liquid and vapour. |
| H332 | Harmful if inhaled. |
Precautionary statements: P210, P233, P241, P242, P260, P271, P304, P312, P403
03 · Physical and chemical properties
Diketene 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 | 127 °C (260.6 °F) | HSDB | |
| 126.1 °C (259 °F) | at 760 mmHg | DOE PAC | |
| Melting point | -6.5 °C (20.3 °F) | HSDB | |
| -7 °C (19.4 °F) | ICSC | ||
| Density | 1.0877 g/cm³ | at 20 °C | HSDB |
| 1.09 g/cm³ | at 20 °C | ICSC | |
| Solubility | Miscible with most organic solvents. Miscible with hexane | HSDB | |
| Slightly soluble in aliphatic hydrocarbons such as hexane (ca. 12.5 wt% at 23 °C), octane, cyclohexane, and methyl cyclohexane | at 23 °C | HSDB | |
| Very slightly soluble in water in which it decomposes slowly | decomposes | HSDB | |
| Vapor pressure | 8.0257 mmHg | at 20 °C | HSDB |
| 7.5006 mmHg | at 20 °C | ICSC | |
| 10.7 mmHg | at 25 °C | HSDB | |
| Flash point | 34 °C (93.2 °F) | HSDB | |
| 33.89 °C (93 °F) | HSDB | ||
| Autoignition temperature | 310 °C (590 °F) | HSDB | |
| 275 °C (527 °F) | ICSC | ||
| Lower explosive limit (LEL) | 2 % by volume | ICSC | |
| Upper explosive limit (UEL) | 11.7 % by volume | ICSC | |
| Vapor density | 2.9 (air = 1) | HSDB | |
| Critical temperature and pressure | 310 °C (590 °F) | HSDB |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
04 · Handling and storage
Storing and handling Diketene
Storage conditions
Store at 32 °F (0 °C) in a standard flammable liquids storage warehouse, room, or cabinet. Special vented containers may be required. Separate from oxidizing materials, acids, and alkalies.
Source: Hazardous Substances Data Bank (HSDB)
Incompatible materials
... Can react vigorously with oxidizing materials. A violent polymerization reaction is catalyzed by acids, bases, or sodium acetate.
Source: Hazardous Substances Data Bank (HSDB)
Reactivity
DIKETENE is a very reactive dimer, it may undergo a spontaneous decomposition followed by explosion or ignition [Vervalin, 1973, p.86]. In the presence of bases, amines, mineral acids or Lewis acids a violent polymerization will occur, accompanied by gas evolution [Zdenek, F. et al., Czech Pat. 156 584, 1975].
Source: CAMEO Chemicals
Planning storage for a mix of chemicals? Check Diketene in the storage compatibility matrix →