Substance profile
N-methyl-2-pyrrolidone
N-methyl-2-pyrrolidone is a clear liquid with a mild amine odor.
01 · Identification
What N-methyl-2-pyrrolidone is
N-methyl-2-pyrrolidone is a clear liquid with a mild amine odor. Its molecular formula is C5H9NO and its molecular weight is 99.13 g/mol. It boils at 202 °C, melts at -25 °C, is miscible with water.
Under the GHS it carries the signal word Danger. It is classed as teratogens.
Other names for N-methyl-2-pyrrolidone
- 1-methyl-2-pyrrolidone
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 |
|---|---|
| H360D | May damage the unborn child. |
| H335 | May cause respiratory irritation. |
| H315 | Causes skin irritation. |
| H319 | Causes serious eye irritation. |
Precautionary statements: P264, P280, P302, P305, P313, P332, P337, P338, P352
03 · Physical and chemical properties
N-methyl-2-pyrrolidone 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 | 202 °C (395.6 °F) | at 760 mmHg | HSDB |
| 202.22 °C (396 °F) | at 760 mmHg | CAMEO | |
| 202 °C (395.6 °F) | ICSC | ||
| Melting point | -25 °C (-13 °F) | HSDB | |
| -22.78 °C (-9 °F) | CAMEO | ||
| -24.4 °C (-11.9 °F) | ICSC | ||
| Density | 1.03 g/cm³ | ICSC | |
| 1.027 g/cm³ | at 25 °C | HSDB | |
| 1.03 g/cm³ | at 25 °C | CAMEO | |
| Solubility | Miscible with water, alcohol, ether, acetone, ethyl acetate, chloroform, benzene | HSDB | |
| Miscible with castor oil | HSDB | ||
| Miscible with lower alcohols and ketones | HSDB | ||
| Vapor pressure | 0.345 mmHg | at 25 °C | HSDB |
| 0.2925 mmHg | at 25 °C | ICSC | |
| Flash point | 95.56 °C (204 °F) | HSDB | |
| 86 °C (186.8 °F) | ICSC | ||
| Autoignition temperature | 346.11 °C (655 °F) | HSDB | |
| 245 °C (473 °F) | ICSC | ||
| Lower explosive limit (LEL) | 1.3 % by volume | ICSC | |
| Expolsion Prevention: Above 96 °C use a closed system and ventilation. | HSDB | ||
| Above 96 °C explosive vapor/air mixtures may be formed. | HSDB | ||
| Upper explosive limit (UEL) | 9.5 % by volume | ICSC | |
| Vapor density | 3.4 (air = 1) | HSDB | |
| Odor threshold | Odor Threshold Low: 4.0 [ppm] | Haz-Map | |
| Odor Threshold High: 10.0 [ppm] | Haz-Map | ||
| Odor thresholds from CSH | Haz-Map | ||
| Critical temperature and pressure | 451 °C (843.8 °F) | HSDB |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
04 · Handling and storage
Storing and handling N-methyl-2-pyrrolidone
Storage conditions
Small quantities can be stored in polyethylene, polypropylene, or clear glass bottles.
Source: Hazardous Substances Data Bank (HSDB)
Incompatible materials
Reacts with sulfur or carbon disulfide at high temperatures and pressures.
Source: Hazardous Substances Data Bank (HSDB)
Reactivity
This amine is a very mild chemical base. It does tend to neutralize acids to form salts plus water. The amount of heat that is evolved per mole of amine in a neutralization is largely independent of the strength of the amine as a base. Amines may be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. Flammable gaseous hydrogen is generated by amines in combination with strong reducing agents, such as hydrides.
Source: CAMEO Chemicals
Planning storage for a mix of chemicals? Check N-methyl-2-pyrrolidone in the storage compatibility matrix →