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

Methacrylic Acid

Methacrylic Acid is clear colorless liquid or colorless crystals with an acrid, repulsive odor.

CAS 79-41-4 C4H6O2 86.09 g/mol Danger

01 · Identification

What Methacrylic Acid is

Methacrylic Acid is clear colorless liquid or colorless crystals with an acrid, repulsive odor. Its molecular formula is C4H6O2 and its molecular weight is 86.09 g/mol. It boils at 163 °C, melts at 16 °C, is soluble in water.

Under the GHS it carries the signal word Danger. It is classed as corrosives.

CAS number79-41-4
EC number201-204-4
Index number607-088-00-5
Molecular formulaC4H6O2
Molecular weight86.09 g/mol
Chemical class Corrosives

Other names for Methacrylic Acid

  • 2-methylpropenoic acid

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 Methacrylic Acid
CodeHazard statement
H312 Harmful in contact with skin.
H302 Harmful if swallowed.
H314 Causes severe skin burns and eye damage.

Precautionary statements: P260, P270, P280, P301, P302, P310, P312, P330, P331, P352

03 · Physical and chemical properties

Methacrylic Acid 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 163 °C (325.4 °F) at 760 mmHg HSDB
162.78 °C (325 °F) NIOSH
162.78 °C (325 °F) at 760 mmHg CAMEO
Melting point 16 °C (60.8 °F) HSDB
16.11 °C (61 °F) NIOSH
Density 1.02 g/cm³ Liquid NIOSH
1.0153 g/cm³ at 20 °C HSDB
1.015 g/cm³ at 20 °C CAMEO
Solubility Soluble in chloroform; miscible with ethanol, ether HSDB
In water solubility, 89 g/L at 20 °C at 20 °C HSDB
(77 °F): 9% at 25 °C NIOSH
Vapor pressure 0.7 mmHg NIOSH
0.65 mmHg at 20 °C CAMEO
0.99 mmHg at 25 °C HSDB
Flash point 76 °C (168.8 °F) open cup HSDB
67.22 °C (153 °F) HSDB
77.22 °C (171 °F) NIOSH
Autoignition temperature 400 °C (752 °F) HSDB
Lower explosive limit (LEL) 1.6 % by volume HSDB
2.4 % by volume CAMEO
Upper explosive limit (UEL) 8.8 % by volume HSDB
2.4 % by volume OSHA
Vapor density 2.97 (air = 1) HSDB
Critical temperature and pressure 370 °C (698 °F) HSDB
Corrosivity Forms corrosive liquid at melting point HSDB

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

04 · Handling and storage

Storing and handling Methacrylic Acid

Storage conditions

Prior to working with this chemical you should be trained on its proper handling and storage. Before entering confined space where this chemical may be present, check to make sure that an explosive concentration does not exist. Store in tightly closed containers in a cool, well ventilated area away from oxidizers (such as perchlorates, peroxides, permanganates, chlorates and nitrates). Methacrylic acid should be stored at temperatures below 15 degrees C. Sources of ignition such as smoking and open flames are prohibited where Methacrylic acid is handled, used, or stored. Wherever Methacrylic acid is used, handled, manufactured, or stored, use explosion-proof electrical equipment and fittings.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Oxidizers, elevated temperatures, hydrochloric acid [Note: Typically contains 100 ppm of the monomethyl ether of hydroquinone to prevent polymerization].

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

METHACRYLIC ACID reacts with strong oxidizing agents. Presents a storage hazard: violent exothermic polymerizations leading to explosion can occur spontaneously, particularly at low inhibitor or stabilizer concentrations [Anon., CISHC Chem. Safety Summ., 1979, 50, p. 34; Bond, J., Loss Prev. Bull., 1991, 101, p. 1].

Source: CAMEO Chemicals

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

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