Appendices 1-18 to: Report on the Health Effects of Selected Pesticide Coformulants

Appendix 17: 1-Methylpyrrolidone (NMP)
128 General description

Molecular formula: C₅H₉NO

Structural formula:

Formula

Molecular weight: 99.13

CAS-no.: 872-50-4

Synonyms: N-methyl-2-pyrrolidone

Methylpyrrolidone

N-Methyl-2-pyrrolidinone

1-Methyl-5-pyrrolidinone

N-Methyl-2-oxypyrrolidine

N-Methyl-2-ketopyrrolidine

NMP

Butyrolactam

N-Methyl-gamma-butyrolactone

1-Methylazacyclopentan-2-one

Description: NMP is a colourless, hygroscopic liquid with a mild amine odour.

Melting point: -23 to -24.4 °C

Boiling point: 202 °C (at 760 mmHg)

Density: 1.034 g/ml (at 20°C)

Vapour pressure: 0.29 mmHg (39 Pa) (at 20°C)

Concentration of

saturated vapours: 1400 mg/m³ (Åkesson 1994)

1600 mg/m³ (calculated)

Conversion factor: 1 ppm = 4.12 mg/m³ (at 20°C and 760 mmHg)

1 mg/m³ = 0.243 ppm

Solubility: Water: Miscible with water.

Highly soluble in lower alcohols, lower ketones, ether, ethyl acetate, chloroform and benzene. Moderately soluble in aliphatic hydrocarbons.

logP_{octanol/water}: -0.46 - 0.42

References: Merck Index (1996), Åkesson (1994), IUCLID (2000), HSDB (2001), Trochimowicz et al. (1994).