Product Name: Methacrylic Acid (MAA)
Chemical Formula: C4H6O2
CAS Number: 79-41-4
Synonyms: 2-Methylpropenoic acid
Recommended Use: Used as a monomer in chemical synthesis, adhesives, resins, and coatings
Supplier Information: Contact details of manufacturer or distributor (address, phone, emergency number)
Emergency Overview: Clear, colorless liquid with an acrid odor. Flammable, corrosive, toxic on ingestion or inhalation. Immediate action needed during exposure incidents.
GHS Classification: Flammable liquids (Category 3), Acute toxicity oral (Category 4), Skin corrosion/irritation (Category 1B), Eye damage/irritation (Category 1), Specific target organ toxicity – Single exposure (Category 3)
Signal Word: Danger
Hazard Statements: Flammable liquid and vapor, causes severe skin burns and eye damage, toxic if swallowed or inhaled, may cause respiratory irritation
Pictograms: Flame, Corrosion, Exclamation Mark
Potential Health Effects: Corrosive to mucous membranes and skin, painful burns, eye irritation, headache, dizziness from vapor, breathing difficulty
Environmental Hazards: Harmful to aquatic life with long lasting effects, risk of bioaccumulation and persistence in waterways.
Chemical Name: Methacrylic acid
Concentration: 99% and above
CAS Registry Number: 79-41-4
Impurities: Trace amounts of inhibitors (e.g., MEHQ for stabilization), water below 1%, minor esters
Stabilizing Additives: Active presence of phenolic inhibitors like MEHQ (monomethyl ether hydroquinone) to prevent polymerization during storage and transport.
General Advice: Move exposed person from area of exposure, seek immediate medical assistance
Inhalation: Remove person to fresh air, support breathing as needed, administer oxygen if breathing is difficult, call a doctor quickly
Skin Contact: Rinse affected skin with running water for at least fifteen minutes, remove contaminated clothing, medical attention required for burns or irritation, discard contaminated shoes
Eye Contact: Flush eyes with copious amounts of water for ten to fifteen minutes, keep eyelids apart, consult an ophthalmologist after initial flushing
Ingestion: Rinse mouth with water, avoid inducing vomiting, immediate medical intervention recommended due to risk of burns and systemic toxicity.
Suitable Extinguishing Media: Use alcohol-resistant foam, carbon dioxide, dry chemical powder, or water spray/fog
Unsuitable Media: Avoid direct high-pressure water streams causing spattering
Specific Hazards: Vapors can form explosive mixtures with air, dense vapors travel long distances to ignition sources, combustion produces toxic fumes including carbon oxides, risk of container rupture in heat
Protective Equipment for Fire-Fighters: Use self-contained breathing apparatus and chemical protective clothing, prevent run-off from entering drains and water courses.
Personal Precautions: Evacuate unnecessary personnel, avoid breathing vapors, ventilate area thoroughly, prevent skin and eye contact, wear chemical-resistant gloves, goggles, and respirators
Environmental Precautions: Contain spills to avoid contamination of ground and surface waters, prevent entry to sewers or confined spaces
Methods for Cleanup: Absorb liquid on inert material (e.g., sand, earth, vermiculite), collect residue in closed, labeled containers for disposal, wipe smaller spills with neutralizing solution, decontaminate area with large amounts of water after product pickup, monitor vapor levels throughout cleanup operation.
Handling Practices: Use only in well-ventilated areas, keep away from open flames, direct sunlight, static discharge or sources of ignition, avoid inhalation or prolonged skin contact, always open containers slowly to release internal pressure, never use near incompatible substances like oxidizing agents, bases, or strong reducing agents
Storage Requirements: Keep containers tightly closed in a cool, dry area, store below 25°C to slow polymerization, maintain with appropriate stabilizer (MEHQ) to avoid hazardous buildup, keep separate from food and feedstuffs, use corrosion-resistant containers and fittings.
Occupational Exposure Limits: OSHA PEL: 20 ppm (70 mg/m³) TWA, ACGIH TLV: 20 ppm (70 mg/m³) TWA
Engineering Controls: Exhaust ventilation, local fume extraction, and use of explosion-proof electrical equipment help reduce vapor buildup and accidental ignition risk
Personal Protective Equipment: Nitrile or neoprene gloves, chemical-resistant goggles, full-face shield during splash risk, acid-resistant apron, and respiratory protection in areas with poor ventilation, emergency eyewash and deluge shower availability
Hygiene Provisions: Always wash hands and face before breaks or after exposure, no smoking or eating in work areas, launder clothes regularly.
Appearance: Clear, colorless to slightly yellowish pungent liquid
Odor: Sharp, acrid and unpleasant
Odor Threshold: 0.1–1.2 ppm
pH: 2.5 (10 g/L, H2O, 20°C)
Melting Point: 15–16°C
Boiling Point: 161°C
Flash Point: 67°C (closed cup)
Evaporation Rate: ~0.42 (BuAc=1)
Flammability: Flammable liquid, emits vapors that may ignite
Upper/Lower Flammability Limits: 2.1–8.2% (v/v) in air
Vapor Pressure: 2.3 hPa (20°C)
Vapor Density: 2.6 (air=1)
Density: 1.015 g/cm³ (20°C)
Solubility: Fully miscible with water, soluble in alcohols, ethers, esters
Partition Coefficient: log Kow: 0.97
Autoignition Temperature: 385°C
Decomposition Temperature: Not precisely defined – decomposes with heat, emitting toxic vapors
Viscosity: 0.92 mPa.s (25°C).
Chemical Stability: Stable in presence of recommended inhibitor and proper storage temperature, rapid polymerization without stabilizer or if heated
Conditions to Avoid: Heat, sunlight, ignition sources, incompatible chemicals, confined unventilated spaces
Incompatible Materials: Strong oxidizers, alkalis, acids, iron, copper, and polymerization initiators
Hazardous Decomposition Products: Fumes of carbon monoxide, carbon dioxide, other toxic, acrid irritants released on combustion or decomposition
Polymerization Risk: May polymerize violently from heat, contamination, absence of stabilizer; keep away from peroxides, azo compounds, and reducing agents.
Routes of Exposure: Inhalation, skin and eye contact, ingestion
Acute Toxicity: LD50 (oral, rat): 1320 mg/kg; LC50 (inhalation, rat, 4h): 7.1 mg/L; LD50 (dermal, rabbit): 500–1000 mg/kg
Skin Corrosion/Irritation: Causes severe burns, blisters, dermatitis upon prolonged contact
Serious Eye Damage/Irritation: Damage to cornea, conjunctival burns, potential for permanent visual impairment
Inhalation Risks: Dizziness, sore throat, cough, shortness of breath, pulmonary edema (delayed in onset), headache
Chronic Exposure: Long term repeat exposure leads to skin sensitization, allergic responses, possible asthma-like symptoms
Mutagenicity: Limited evidence or studies, not classed as human carcinogen by IARC or EPA
Other Effects: Systemic absorption after ingestion can damage gastrointestinal lining and cause multi-organ effects.
Eco-toxicity: Harmful to aquatic invertebrates (Daphnia EC50: 42.5 mg/L, 48hr), fish (LC50: 85 mg/L, 96hr for Oncorhynchus mykiss), algae toxic at elevated concentrations
Persistence and Degradability: Readily biodegradable under aerobic conditions, less persistent than many industrial monomers
Bioaccumulation: Low potential due to low Kow and rapid breakdown
Mobility in Soil: Moderate when spilled, readily migrates to groundwater in case of soil contamination
Other Adverse Effects: Oxygen depletion in confined aquatic systems, may damage microfauna and disturb local balance if released in quantity.
Waste Treatment: Contact licensed waste disposal contractors, aim for incineration under controlled conditions with off-gas scrubbing
Contaminated Packaging: Empty containers retain product residue; rinse with neutralizing solutions before recycling or landfill, triple rinse standard
Disposal of Spills: Collect absorbed material in sealable, properly labeled containers, dispose as hazardous waste according to local, regional, and national regulations
Precautions: Never allow liquid or solidified product to enter drains, natural waterways, or open soil near water sources.
UN Number: 2531
Shipping Name: METHACRYLIC ACID, stabilized
Transport Hazard Class: 8 (Corrosive), 3 (Flammable Liquid)
Packing Group: II
Labels: Corrosive, Flammable (GHS07, GHS05, GHS02)
Special Precautions During Transport: Tanks, drums, or containers must carry inhibitor, kept upright, clearly labeled, protect from physical damage or heat, segregate from incompatible transport goods
Regulatory Codes: ADR/RID, IMDG, IATA recognized as dangerous for international carriage, special attention needed for spill or fire contingency.
OSHA Regulation: Hazardous Chemical under OSHA 29 CFR 1910.1200
TSCA: Listed as existing substance
REACH Registration: Registered and permitted for use with restrictions
DOT (U.S.): Regulated dangerous good, specified in 49 CFR 172.101
SARA Title III Sections 311/312: Immediate (acute) health hazard, fire hazard, delayed health hazard
California Proposition 65: Not currently listed as carcinogen or reproductive toxin
Canada WHMIS Classification: D1B, D2B, B3
Other Requirements: All users must abide by proper labeling, workplace exposure monitoring, provision of safety training, access to fresh air and decontamination stations.
