CAS No.: 79-41-4
Molecular Weight: 86.08920
Molecular Formula: C₄H₆O₂
Chinese Synonyms:
Methacrylic acid; 2-Methyl-2-propenoic acid; 2-Methylacrylic acid; α-Methylacrylic acid;

Physical Data:

Properties and Stability:
Colorless crystals or transparent liquid with a pungent odor. Appearance: colorless or pale yellow transparent liquid at temperatures >16°C, free of mechanical impurities; white crystals at temperatures <16°C.
Soluble in hot water, ethanol, ether, and most organic solvents. Easily polymerizes into water-soluble polymers. Flammable, poses a combustion risk when exposed to high heat or open flames; decomposes upon heating to produce toxic gases.

Health Hazards:
Routes of Exposure: Inhalation, ingestion, skin absorption.
Health Hazards: Irritating to the nose and throat; high concentrations may cause pulmonary changes. Irritating to the skin and may cause burns. Eye contact can result in burns and permanent damage.
Chronic Effects: May cause damage to the lungs, liver, and kidneys. Skin sensitizer, leading to itching and rashes.

Leak Handling and Protective Measures:
1. In case of leakage, evacuate personnel from the contaminated area to a safe zone; prohibit unauthorized entry into the contaminated area.
2. When airborne concentrations exceed limits, emergency personnel must wear respirators, chemical safety goggles, chemical protective clothing, and rubber gloves. After work, shower and change clothes, paying attention to personal hygiene.
3. Do not directly contact the leaked substance; contain the leak if safe to do so.
4. Absorb with sand or other non-combustible adsorbents, then transport to a waste disposal site for treatment.
5. For large spills, use dikes to contain, then collect, transfer, recycle, or dispose of after neutralization.

First Aid Measures
Skin/Eye Contact: Immediately rinse with plenty of water and seek medical advice.
Inhalation: Quickly move to fresh air. Keep airways clear. Perform artificial respiration if necessary. Seek medical attention.
Ingestion: Give the affected person large amounts of water to drink, induce vomiting, and seek medical attention.
Fire Extinguishing Methods: Water fog, carbon dioxide, sand, foam.

Storage Precautions:
1. Store in a cool, well-ventilated area away from ignition sources and heat. No smoking in the workplace. Use explosion-proof ventilation systems and equipment. Prevent vapor leakage into the workplace air.
2. Handle with care during transport to avoid damage to packaging and containers. The storage area should be equipped with appropriate types and quantities of firefighting equipment and leak emergency handling devices.
3. Separate from oxidizers, amines, and alkalis. Avoid mixed storage. Do not store in large quantities or for extended periods.
4. Ensure emptied containers are free of residue.

Product Applications:
1. Methacrylic acid is an important organic chemical raw material and polymer intermediate. Its most important derivative, methyl methacrylate, is used to produce organic glass for aircraft and civil building windows, as well as buttons, sun filters, and automotive lamp lenses.
2. The coatings produced have excellent suspension and durability. The adhesives made can be used for metals, leather, plastics, and building materials. Methacrylate polymer emulsions are used as fabric finishing agents and antistatic agents. Additionally, methacrylic acid can serve as a raw material for synthetic rubber, manufacturing resins, plastics, high molecular polymers, and esters. For example, tempered glass—methyl methacrylate.
3. Used in organic synthesis and polymer preparation. Also used in the production of thermosetting coatings, synthetic rubber, fabric treatment agents, leather treatment agents, ion exchange resins, insulating materials, antistatic agents, etc. It is a cross-linking monomer for manufacturing acrylic ester solvent-based and emulsion adhesives, improving adhesive strength and stability.