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Chemical Datasheet

METHACRYLIC ACID, STABILIZED

8 - Corrosive

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 79-41-4   (METHACRYLIC ACID)
  • 2531
  • Corrosive
none
NIOSH Pocket Guide International Chem Safety Card
Methacrylic acid
  • METHACRYLIC ACID
NFPA 704
Diamond Hazard Value Description
2
3 2
Blue Health 3 Can cause serious or permanent injury.
Red Flammability 2 Must be moderately heated or exposed to relatively high ambient temperatures before ignition can occur.
Yellow Instability 2 Readily undergoes violent chemical changes at elevated temperatures and pressures.
White Special
(NFPA, 2010)
General Description
A clear colorless liquid with a pungent odor. Corrosive to metals and tissue. Combustible. Flash point 170°F. Melting point 61°F. 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.

Hazards

Reactivity Alerts
Air & Water Reactions
Water soluble.
Fire Hazard
Excerpt from 153 Polymerizable warning [Substances - Toxic and/or Corrosive (Combustible); polymerization hazard]:

Combustible material: may burn but does not ignite readily. When heated, vapors may form explosive mixtures with air: indoors, outdoors and sewers explosion hazards. Those substances designated with a (P) may polymerize explosively when heated or involved in a fire. Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated. Runoff may pollute waterways. Substance may be transported in a molten form. (ERG, 2020)
Health Hazard
Excerpt from 153 Polymerizable warning [Substances - Toxic and/or Corrosive (Combustible); polymerization hazard]:

TOXIC; inhalation, ingestion or skin contact with material may cause severe injury or death. Contact with molten substance may cause severe burns to skin and eyes. Avoid any skin contact. Effects of contact or inhalation may be delayed. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may be corrosive and/or toxic and cause environmental contamination. (ERG, 2020)
Reactivity Profile
Corrosive, moderately toxic liquid or low-melting solid, m.p. 16°C. Flammable when exposed to heat, flame or strong oxidizers. A storage hazard; violent exothermic polymerization leading to explosion occur spontaneously, particularly at low inhibitor or stabilizer concentration [Anon., CISHC Chem. Safety Summ., 1979, 50, p. 34; Bond, J., Loss Prev. Bull., 1991, 101, p. 1].
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents

Use caution: Liquids with this reactive group classification have been known to react with the absorbents listed below.

Response Recommendations

Isolation and Evacuation
Excerpt from 153 Polymerizable warning [Substances - Toxic and/or Corrosive (Combustible); polymerization hazard]:

IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids.

SPILL: Increase the immediate precautionary measure distance, in the downwind direction, as necessary.

FIRE: If tank, rail car or tank truck is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2020)
Firefighting
Excerpt from 153 Polymerizable warning [Substances - Toxic and/or Corrosive (Combustible); polymerization hazard]:

SMALL FIRE: Dry chemical, CO2 or water spray.

LARGE FIRE: Dry chemical, CO2, alcohol-resistant foam or water spray. If it can be done safely, move undamaged containers away from the area around the fire. Dike runoff from fire control for later disposal.

FIRE INVOLVING TANKS OR CAR/TRAILER LOADS: Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles. Do not get water inside containers. Cool containers with flooding quantities of water until well after fire is out. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks engulfed in fire. (ERG, 2020)
Non-Fire Response
Excerpt from 153 Polymerizable warning [Substances - Toxic and/or Corrosive (Combustible); polymerization hazard]:

ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area. Do not touch damaged containers or spilled material unless wearing appropriate protective clothing. Stop leak if you can do it without risk. Prevent entry into waterways, sewers, basements or confined areas. Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers. DO NOT GET WATER INSIDE CONTAINERS. (ERG, 2020)
Protective Clothing
Excerpt from NIOSH Pocket Guide for Methacrylic acid:

Skin: PREVENT SKIN CONTACT - Wear appropriate personal protective clothing to prevent skin contact.

Eyes: PREVENT EYE CONTACT - Wear appropriate eye protection to prevent eye contact.

Wash skin: WHEN CONTAMINATED - The worker should immediately wash the skin when it becomes contaminated.

Remove: WHEN WET OR CONTAMINATED - Work clothing that becomes wet or significantly contaminated should be removed and replaced.

Change: DAILY - Workers whose clothing may have become contaminated should change into uncontaminated clothing before leaving the work premises.

Provide:
• EYEWASH - Eyewash fountains should be provided in areas where there is any possibility that workers could be exposed to the substances; this is irrespective of the recommendation involving the wearing of eye protection.
• QUICK DRENCH - Facilities for quickly drenching the body should be provided within the immediate work area for emergency use where there is a possibility of exposure. [Note: It is intended that these facilities provide a sufficient quantity or flow of water to quickly remove the substance from any body areas likely to be exposed. The actual determination of what constitutes an adequate quick drench facility depends on the specific circumstances. In certain instances, a deluge shower should be readily available, whereas in others, the availability of water from a sink or hose could be considered adequate.] (NIOSH, 2023)
DuPont Tychem® Suit Fabrics
Normalized Breakthrough Times (in Minutes)
Chemical CAS Number State QS QC SL C3 TF TP RC TK RF
Methacrylic acid 79-41-4 Liquid 81 >480 >480 >480 >480 >480
Methyl propenoic acid, 2- 79-41-4 Liquid 81 >480 >480 >480 >480 >480
> indicates greater than.

Special Warning from DuPont: Tychem® and Tyvek® fabrics should not be used around heat, flames, sparks or in potentially flammable or explosive environments. Only...

(DuPont, 2023)

First Aid
Excerpt from NIOSH Pocket Guide for Methacrylic acid:

Eye: IRRIGATE IMMEDIATELY - If this chemical contacts the eyes, immediately wash (irrigate) the eyes with large amounts of water, occasionally lifting the lower and upper lids. Get medical attention immediately.

Skin: WATER FLUSH IMMEDIATELY - If this chemical contacts the skin, immediately flush the contaminated skin with water. If this chemical penetrates the clothing, immediately remove the clothing and flush the skin with water. Get medical attention promptly.

Breathing: RESPIRATORY SUPPORT - If a person breathes large amounts of this chemical, move the exposed person to fresh air at once. If breathing has stopped, perform artificial respiration. Keep the affected person warm and at rest. Get medical attention as soon as possible.

Swallow: MEDICAL ATTENTION IMMEDIATELY - If this chemical has been swallowed, get medical attention immediately. (NIOSH, 2023)

Physical Properties

Chemical Formula:
  • C4H6O2
Flash Point: 171°F (NIOSH, 2023)
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature: data unavailable
Melting Point: 61°F (NIOSH, 2023)
Vapor Pressure: 0.7 mmHg (NIOSH, 2023)
Vapor Density (Relative to Air): data unavailable
Specific Gravity: 1.02 (Liquid) (NIOSH, 2023) - Denser than water; will sink
Boiling Point: 325°F at 760 mmHg (NIOSH, 2023)
Molecular Weight: 86.1 (NIOSH, 2023)
Water Solubility: 9 % at 77°F (NIOSH, 2023)
Ionization Energy/Potential: data unavailable
IDLH: data unavailable

AEGLs (Acute Exposure Guideline Levels)

Interim AEGLs for Methacrylic acid (79-41-4)
Exposure Period AEGL-1 AEGL-2 AEGL-3
10 minutes 6.7 ppm 76 ppm 280 ppm
30 minutes 6.7 ppm 76 ppm 280 ppm
60 minutes 6.7 ppm 61 ppm 220 ppm
4 hours 6.7 ppm 38 ppm 140 ppm
8 hours 6.7 ppm 25 ppm 71 ppm
(NAC/NRC, 2023)

ERPGs (Emergency Response Planning Guidelines)

No ERPG information available.

PACs (Protective Action Criteria)

Chemical PAC-1 PAC-2 PAC-3
Methacrylic acid (79-41-4) 6.7 ppm 61 ppm 220 ppm LEL = 16000 ppm
(DOE, 2018)

Regulatory Information

EPA Consolidated List of Lists

No regulatory information available.

CISA Chemical Facility Anti-Terrorism Standards (CFATS)

No regulatory information available.

OSHA Process Safety Management (PSM) Standard List

No regulatory information available.

Alternate Chemical Names