Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

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Substance profile

Methacrylonitrile

Methacrylonitrile is a colorless liquid with odor-like bitter almonds.

CAS 126-98-7 C4H5N 67.09 g/mol Danger

01 · Identification

What Methacrylonitrile is

Methacrylonitrile is a colorless liquid with odor-like bitter almonds. Its molecular formula is C4H5N and its molecular weight is 67.09 g/mol. It boils at 90.3 °C, melts at -35.8 °C, is miscible with water.

Under the GHS it carries the signal word Danger. It is classed as flammable agents - 3rd degree.

CAS number126-98-7
EC number204-817-5
Index number608-010-00-2
Molecular formulaC4H5N
Molecular weight67.09 g/mol
Chemical class Flammable agents - 3rd degree

Other names for Methacrylonitrile

  • 2-methyl-2-propene nitrile

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.

Signal wordDanger
Hazard statements assigned to Methacrylonitrile
CodeHazard statement
H225 Highly flammable liquid and vapour.
H331 Toxic if inhaled.
H311 Toxic in contact with skin.
H301 Toxic if swallowed.
H317 May cause an allergic skin reaction.

Precautionary statements: P210, P233, P241, P242, P260, P261, P270, P271, P272, P280, P301, P302, P304, P310, P313, P330, P333, P352, P403

03 · Physical and chemical properties

Methacrylonitrile 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 90.3 °C (194.5 °F) at 760 mmHg HSDB
90.56 °C (195 °F) NIOSH
90 °C (194 °F) at 760 mmHg CAMEO
Melting point -35.8 °C (-32.4 °F) HSDB
-35.56 °C (-32 °F) NIOSH
-35.78 °C (-32.4 °F) CAMEO
Density 0.8 g/cm³ NIOSH
0.8001 g/cm³ at 20 °C HSDB
Solubility Miscible with acetone, octane, toluene @ 20-25 °C HSDB
Sol in alcohol, ether HSDB
In water, 2.54X10+4 mg/l @ 25 °C at 25 °C HSDB
Vapor pressure 71.2 mmHg at 25 °C HSDB
71 mmHg at 25 °C NIOSH
64.9553 mmHg at 25 °C ICSC
Flash point 13 °C (55.4 °F) HSDB
1.11 °C (34 °F) NIOSH
12.78 °C (55 °F) CAMEO
Lower explosive limit (LEL) 2 % by volume HSDB
Upper explosive limit (UEL) 6.8 % by volume HSDB
Vapor density 2.31 (air = 1) HSDB
2.3 (air = 1) ICSC
Odor threshold ... IT SHOULD BE NOTED THAT METHACRYLONITRILE CANNOT BE DETECTED BY ITS SMELL EVEN AT CONCENTRATIONS WHICH ARE ALREADY DANGEROUS FOR HUMANS. HSDB
An odor threshold of 2.1 ppm has been reported. HSDB
Odor Threshold Low: 6.9 [ppm] Haz-Map

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

04 · Handling and storage

Storing and handling Methacrylonitrile

Incompatible materials

Strong acids, strong oxidizers, alkali, light. [Note: Polymerization may occur due to elevated temperature, visible light, or contact with a concentrated alkali.]

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

METHACRYLONITRILE is a colorless, flammable, toxic liquid. Explosive in the form of vapor when exposed to heat, flame or sparks. When heated to decomposition it emits toxic fumes of nitrile and oxides of nitrogen [Lewis, 3rd ed., 1993, p. 829].

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Methacrylonitrile in the storage compatibility matrix →

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