Functional Roles
Industries Served
Physical Properties
physical_description
Methacrylic acid, stabilized appears as a clear colorless liquid with a pungent odor. Corrosive to metals and tissue. Combustible. Flash point 170 u00b0F. Melting point 61 u00b0F. May polymerize if contaminated or heated. If polymerization takes place inside a closed container, the container may violently rupture. Less dense than water and is soluble in water. Vapors heavier than air. Used to make plastics.
color/form
Clear colorless liquid or colorless crystals
odor
Acrid, repulsive odor
boiling_point
325 u00b0F at 760 mmHg (NIOSH, 2024)
melting_point
61 u00b0F (NIOSH, 2024)
flash_point
153 u00b0F (67 u00b0C) (closed cup)
solubility
greater than or equal to 100 mg/mL at 63 u00b0F (NTP, 1992)
density
1.015 at 68 u00b0F (USCG, 1999) - Denser than water; will sink
vapor_density
2.97 (NTP, 1992) - Heavier than air; will sink (Relative to Air)
vapor_pressure
0.65 mmHg at 68 u00b0F ; 1 mmHg at 77 u00b0F (NTP, 1992)
logp
log Kow = 0.93
henry's_law_constant
Henry's Law constant = 3.9X10-7 atm-cu m/mole at 25 u00b0C
stability/shelf_life
Acrylic acid and methacrylic acid readily polymerize in the presence of light, heat and oxygen, and also under the action of oxidizing agents such as peroxides.
autoignition_temperature
752 u00b0F (USCG, 1999)
decomposition
Hazardous decomposition products include carbon monoxide and acrid fumes. /Methacrylic acid, inhibited/
viscosity
1.38 mPa.s at 24 u00b0C
corrosivity
Forms corrosive liquid at melting point
heat_of_vaporization
0.418 kJ/mol at 101.3 kPa (760 mm Hg)
surface_tension
0.0265 N/m
polymerization
Hazardous polymerizaton may occur. Usually contains inhibitors to prevent polymerization. Polymerizaton may be caused by elevated temperature, oxidizers, peroxides, or sunlight. ... Uninhibited monomer vapor may form polymer in vents and other confined spaces. /Methacrylic acid, inhibited/
refractive_index
Index of refraction: 1.43143 at 20 u00b0C/D
dissociation_constants
pKa = 4.65
kovats_retention_index
711
other_experimental_properties
Boiling point: 81 u00b0C at 30 mm Hg; 63 u00b0C at 12 mm Hg; polymer forms ceramic-looking mass, sol in absolute alcohol, from which it is precipitated by ether; polymerizes easily, especially on heating or in the presence of traces of HCl
GHS / SDS Safety
Danger
Irritant
Acute Toxic
Health Hazard
Corrosive
- H370: Causes damage to organs [Danger Specific target organ toxicity, single exposure]
- H402: Harmful to aquatic life [Hazardous to the aquatic environment, acute hazard]
- H302: Harmful if swallowed [Warning Acute toxicity, oral]
- H304: May be fatal if swallowed and enters airways [Danger Aspiration hazard]
- H335: May cause respiratory irritation [Warning Specific target organ toxicity, single exposure; Respiratory tract irritation]
- H302 (99%): Harmful if swallowed [Warning Acute toxicity, oral]
- H314 (> 99.9%): Causes severe skin burns and eye damage [Danger Skin corrosion/irritation]
- H311: Toxic in contact with skin [Danger Acute toxicity, dermal]
- H311 (75.8%): Toxic in contact with skin [Danger Acute toxicity, dermal]
- H373: May causes damage to organs through prolonged or repeated exposure [Warning Specific target organ toxicity, repeated exposure]
- H312: Harmful in contact with skin [Warning Acute toxicity, dermal]
- H318: Causes serious eye damage [Danger Serious eye damage/eye irritation]
- H227: Combustible liquid [Warning Flammable liquids]
- H318 (72.4%): Causes serious eye damage [Danger Serious eye damage/eye irritation]
- H335 (76.6%): May cause respiratory irritation [Warning Specific target organ toxicity, single exposure; Respiratory tract irritation]
- H372: Causes damage to organs through prolonged or repeated exposure [Danger Specific target organ toxicity, repeated exposure]
- H314: Causes severe skin burns and eye damage [Danger Skin corrosion/irritation]
- H312 (25.5%): Harmful in contact with skin [Warning Acute toxicity, dermal]
- H332 (75.4%): Harmful if inhaled [Warning Acute toxicity, inhalation]
Chemical Identity
| CAS Number | 79-41-4 |
| IUPAC Name | 2-methylprop-2-enoic acid |
| InChI Key | CERQOIWHTDAKMF-UHFFFAOYSA-N |
| PubChem CID | 4093 |
| INCI Name | METHACRYLIC ACID |
Synonyms & Trade Names
Full Description
Methacrylic acid (MAA) is an unsaturated carboxylic acid with the molecular formula C4H6O2 that functions as a pH adjustment agent in industrial applications. This chemical is primarily utilized in the coatings and construction industries where precise pH control is critical for product performance and stability.