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METHACRYLIC ACID
ICSC: 0917
Peer-Review Status: 28.03.1996 Validated
2-Methylpropenoic acid
alpha-Methylacrylic acid 
CAS #: 79-41-4 RTECS #: OZ2975000
UN #: 2531 (stabilized)
EC #: 607-088-00-5
EINECS #: 201-204-4
    Formula: C4H6O2 / CH2=C(CH3)COOH
Molecular mass: 86.09

TYPES OF
HAZARD /
EXPOSURE
ACUTE HAZARDS / SYMPTOMS      PREVENTION      FIRST AID / FIRE FIGHTING
FIRE Combustible. Gives off irritating or toxic fumes (or gases) in a fire.  NO open flames.  Use AFFF, alcohol-resistant foam, powder, carbon dioxide. 
EXPLOSION Above 77°C explosive vapour/air mixtures may be formed.  Above 77°C use a closed system and ventilation.  In case of fire: keep drums, etc., cool by spraying with water. 
 
EXPOSURE   AVOID ALL CONTACT!   
Inhalation Cough. Burning sensation. Shortness of breath. Laboured breathing.  Use ventilation (not if powder), local exhaust or breathing protection.  Fresh air, rest. Half-upright position. Refer for medical attention. 
Skin Redness. Skin burns. Pain. Blisters.  Protective clothing.  First rinse with plenty of water for at least 15 minutes, then remove contaminated clothes and rinse again. 
Eyes Redness. Pain. Loss of vision. Severe deep burns.  Wear face shield.  First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention. 
Ingestion Abdominal cramps. Abdominal pain. Burning sensation. Weakness.  Do not eat, drink, or smoke during work. Wash hands before eating.  Rinse mouth. Rest. Refer for medical attention . 

SPILLAGE DISPOSAL
PACKAGING & LABELLING
Collect leaking and spilled liquid in sealable plastic containers as far as possible. Cautiously neutralize remainder with aqueous sodium carbonate or lime. Then wash away with plenty of water. Do NOT absorb in saw-dust or other combustible absorbents. Personal protection: complete protective clothing including self-contained breathing apparatus.  Do not transport with food and feedstuffs. 
EC Classification
Symbol: C; R: 21/22-35; S: (1/2)-26-36/37/39-45; Note: D 
UN Classification
UN Hazard Class: 8; UN Pack Group: II 
GHS Classification
 

EMERGENCY RESPONSE SAFE STORAGE
Transport Emergency Card: TEC (R)-80S2531.
NFPA Code: H3; F2; R2. 
Separated from strong oxidants and food and feedstuffs. Cool. Keep in the dark. Keep in a well-ventilated room. Store only if stabilized. 

IMPORTANT DATA
Physical State; Appearance
COLOURLESS LIQUID OR COLOURLESS CRYSTALS WITH CHARACTERISTIC ODOUR. 

Physical dangers
Vapours are uninhibited and may polymerize, causing blockage of vents. 

Chemical dangers
The substance readily polymerizes due to heating or under the influence of light, oxidizing agents such as peroxides, or in the presence of traces of hydrochloric acid. This generates fire or explosion hazard. Attacks metals. 

Occupational exposure limits
TLV: 20ppm as TWA; (ACGIH 2004).
MAK: 5 ppm, 18 mg/m³; Peak limitation category: I(2); Pregnancy risk group: C; (DFG 2005). 

Routes of exposure
The substance can be absorbed into the body by inhalation. 

Inhalation risk
A harmful contamination of the air will be reached rather slowly on evaporation of this substance at 20°C. 

Effects of short-term exposure
The substance is corrosive to the eyes, skin and respiratory tract. Corrosive on ingestion. Inhalation of the vapour may cause lung oedema. See Notes. 

Effects of long-term or repeated exposure
 


PHYSICAL PROPERTIES ENVIRONMENTAL DATA
Boiling point: 159-163°C
Melting point: 16°C
Relative density (water = 1): 1.02
Solubility in water: moderate
Vapour pressure, Pa at 25°C: 130
Relative vapour density (air = 1): 2.97
Relative density of the vapour/air-mixture at 20°C (air = 1): 1.00
Flash point: 68°C c.c., 77°C o.c.
Explosive limits, vol% in air: 1.6-8.8
Octanol/water partition coefficient as log Pow: 0.93  
 

NOTES
The symptoms of lung oedema often do not become manifest until a few hours have passed and they are aggravated by physical effort.
Rest and medical observation are therefore essential.
Immediate administration of an appropriate inhalation therapy by a doctor or a person authorized by him/her, should be considered.
An added stabilizer or inhibitor can influence the toxicological properties of this substance, consult an expert.
> Card has been partly updated in October 2004 and 2005.
See sections Occupational Exposure Limits, EU classification, Emergency Response. 

ADDITIONAL INFORMATION
 

IPCS
International
Programme on
Chemical Safety
WHO ILO EC Prepared in the context of cooperation between the International Programme on Chemical Safety and the European Commission
© IPCS 2004-2012
LEGAL NOTICE Neither the EC nor the IPCS nor any person acting on behalf of the EC or the IPCS is responsible for the use which might be made of this information.


    See Also:
       Toxicological Abbreviations
       Methacrylic acid (SIDS)