Methacrylic acid, Methlacrylic Acid,  79-41-4 

Methacrylic acid, Methlacrylic Acid,  79-41-4 

CAS: 79-41-4

Molecular Formula: C4H6O2

Names and Identifiers

Physico-chemical Properties

Risk and Safety

Hazard Symbols	C - Corrosive
Risk Codes	R21/22 - Harmful in contact with skin and if swallowed. R35 - Causes severe burns R37 - Irritating to the respiratory system R20/21/22 - Harmful by inhalation, in contact with skin and if swallowed.
Safety Description	S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S36/37/39 - Wear suitable protective clothing, gloves and eye/face protection. S45 - In case of accident or if you feel unwell, seek medical advice immediately (show the label whenever possible.)
UN IDs	UN 2531 8/PG 2
WGK Germany	1
RTECS	OZ2975000
TSCA	Yes
HS Code	2916 13 00
Hazard Class	8
Packing Group	II
Toxicity	LD50 orally in Rabbit: 1320 mg/kg

Upstream Downstream Industry

Nature

A colorless transparent liquid at room temperature. Melting Point 14 °c. Boiling point 159~163 deg C (look kPa). The relative density was 1. 0153. Flash point 77 °c. Viscosity 1.3mPa.s. Refractive index 4314. Soluble in hot water, ethanol and most organic solvents. Easy to polymerize. It can form explosive mixture with air, and the explosion limit is 2.1% ~ l 2.5%.

Preparation Method

1. acetone cyanohydrin method acetone and hydrocyanic acid are reacted in the presence of an alkali catalyst to generate acetone cyanohydrin, and then reacted with concentrated sulfuric acid to generate methacrylamide sulfate, which is then hydrolyzed to generate methacrylic acid. Acetone cyanohydrin and sulfuric acid are required to contain no water in the production, otherwise acetone or methyl isobutyrate will be left in the product, which will affect the quality of the product.
2. isobutylene oxidation isobutylene is oxidized in two steps, methacrolein is generated in the first step, methacrylic acid is generated in the second step, and then a qualified product is obtained by rectification. Tert-butanol may also be used instead of isobutene.
3. the hydrolysis method of methacrylonitrile is obtained by using isobutylene as a raw material through ammonia oxygen and hydrolysis.
4. methacrolein is prepared by isobutane oxidation through oxidation, and then obtained by oxidation.;

Use

important organic chemical raw materials and polymer intermediates. Its most important derivatives of methyl methacrylate production of organic glass can be used in aircraft and civil building windows, can also be processed into buttons, solar filters and automotive light lenses; the produced coating has superior suspension, Rheology and durability properties; The prepared binder can be used for the adhesion of metal, leather, plastic and building materials; Methacrylate polymer emulsion is used as fabric finishing agent and antistatic agent. In addition, methacrylic acid can also be used as a raw material for synthetic rubber.

Safety

• This product has moderate toxicity, strong irritation to the skin and mucous membranes, rats by mouth ld508400 mg/kg. But found no carcinogenic phenomenon. The allowable limit concentration in the workplace is 100 × 10-6 (temporary working area). Good ventilation conditions are required in the production workshop, and the operator should wear protective equipment, especially protective goggles. Rinse with plenty of water when touching the skin.
• packed in polyethylene-lined aluminum or glass and stainless steel containers with a net weight of 200kg. The storage period is about three months. When thawing, the thawing temperature should be about 25 ° C at room temperature, and it can be used after complete melting and mixing. The hazardous materials shall be stored and transported according to the regulations.

Reference Information