Methacrolein

70.08980

70.09

201-150-1

9HRB24892H

1259

8260

2396

DTXSID0052540

COLORLESS LIQUID

29121900

17.07000

0.76140

Methacrylaldehyde appears as a colorless liquid. Less dense than water. May be toxic by ingestion, inhalation and skin absorption. Severely irritating to skin and eyes. Used to make plastics.

0.849 g/cm³ @ Temp: 25 °C

-81 °C

68.4 °C

-15ºC

1.4145

H2O: 6 g/100 mL (20 ºC)

2-8ºC

121 mm Hg ( 20 °C)

2.4 (vs air)

vol% in air: 2.6

3.35e-11 cm3/molecule*sec

2.32e-04 atm-m3/mole

CONVERSION FACTORS: 1 MG/L= 349 PPM; 1 PPM= 2.8 MG/CU M|Liquid molar volume = 0.08320 cu m/kmol|Heat of Formation (gas) = -70.8 kJ/mol at 25 °C

Highly flammable. Soluble in water.

Aldehydes

Highly Flammable

METHACRYLALDEHYDE is an aldehyde. Aldehydes are frequently involved in self-condensation or polymerization reactions. These reactions are exothermic; they are often catalyzed by acid. Aldehydes are readily oxidized to give carboxylic acids. Flammable and/or toxic gases are generated by the combination of aldehydes with azo, diazo compounds, dithiocarbamates, nitrides, and strong reducing agents. Aldehydes can react with air to give first peroxo acids, and ultimately carboxylic acids. These autoxidation reactions are activated by light, catalyzed by salts of transition metals, and are autocatalytic (catalyzed by the products of the reaction). The addition of stabilizers (antioxidants) to shipments of aldehydes retards autoxidation.

295 °C

2299 kJ/mol @ 25 °C

The vapour is heavier than air and may travel along the ground; distant ignition possible.

29.0 kJ/mol @ 101.3 kPa

Critical temperature: 257 °C; Critical pressure: 4.36 mPa

II

3

UN 2396

3

R11; R24/25; R26; R34

S16-S26-S28-S36/37/39-S45

OZ2625000

F; T

Fireproof. Separated from strong oxidants, acids, bases and food and feedstuffs. Cooled. Keep in the dark. Well closed. Keep under inert gas. Store only if stabilized. Provision to contain effluent from fire extinguishing.

Stable. Incompatible with strong bases, strong oxidising agents, strong reducing agents. Light and air-sensitive. Hazardous polymerisation may occur.

P210-P280-P301 + P310-P305 + P351 + P338-P310

H225-H301 + H311-H314

SRP: At the time of review, criteria for land treatment or burial (sanitary landfill) disposal practices are subject to significant revision. Prior to implementing land disposal of waste residue (including waste sludge), consult with environmental regulatory agencies for guidance on acceptable disposal practices.

UN 2396

Excerpt from ERG Guide 131P [Flammable Liquids - Toxic]: HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames. Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapor explosion and poison hazard indoors, outdoors or in sewers. Those substances designated with a (P) may polymerize explosively when heated or involved in a fire. Runoff to sewer may create fire or explosion hazard. Containers may explode when heated. Many liquids are lighter than water. (ERG, 2016)|Highly flammable. Vapour/air mixtures are explosive.|Flammable - 3rd degree, Reactive - 2nd degree

|Danger|H225 (93.24%): Highly Flammable liquid and vapor [Danger Flammable liquids]|P201, P202, P210, P233, P240, P241, P242, P243, P260, P264, P270, P271, P273, P280, P281, P284, P301+P310, P301+P330+P331, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P308+P313, P310, P312, P320, P321, P322, P330, P361, P363, P370+P378, P391, P403+P233, P403+P235, P405, and P501|Aggregated GHS information provided by 148 companies from 9 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.|H225: Highly Flammable liquid and vapor [Danger Flammable liquids]|P210, P233, P240, P241, P242, P243, P260, P261, P264, P270, P271, P280, P284, P301+P310, P301+P330+P331, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P310, P312, P320, P321, P322, P330, P361, P363, P370+P378, P403+P233, P403+P235, P405, and P501

Excerpt from ERG Guide 131P [Flammable Liquids - Toxic]: As an immediate precautionary measure, isolate spill or leak area for at least 50 meters (150 feet) in all directions. SPILL: Increase, in the downwind direction, as necessary, the isolation distance shown above. 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, 2016)

Excerpt from ERG Guide 131P [Flammable Liquids - Toxic]: Fully encapsulating, vapor-protective clothing should be worn for spills and leaks with no fire. ELIMINATE all ignition sources (no smoking, flares, sparks or flames in immediate area). All equipment used when handling the product must be grounded. Do not touch or walk through spilled material. Stop leak if you can do it without risk. Prevent entry into waterways, sewers, basements or confined areas. A vapor-suppressing foam may be used to reduce vapors. SMALL SPILL: Absorb with earth, sand or other non-combustible material and transfer to containers for later disposal. Use clean, non-sparking tools to collect absorbed material. LARGE SPILL: Dike far ahead of liquid spill for later disposal. Water spray may reduce vapor, but may not prevent ignition in closed spaces. (ERG, 2016)

Excerpt from ERG Guide 131P [Flammable Liquids - Toxic]: Wear positive pressure self-contained breathing apparatus (SCBA). Wear chemical protective clothing that is specifically recommended by the manufacturer. It may provide little or no thermal protection. Structural firefighters' protective clothing provides limited protection in fire situations ONLY; it is not effective in spill situations where direct contact with the substance is possible. (ERG, 2016)

FIRE HAZARD: DANGEROUS, WHEN EXPOSED TO HEAT, FLAME OR OXIDIZERS. ...CAN REACT VIGOROUSLY WITH OXIDIZING MATERIALS.

Explosive limits , vol% in air: 2.6-?

CARBON DIOXIDE, ALC FOAM, FOAM, DRY CHEMICAL.

PRECAUTIONS FOR HANDLING REACTIVE UNSATURATED ALDEHYDES SUCH AS...METHACROLEIN...SHOULD BE SAME AS THOSE FOR OTHER HIGHLY ACTIVE EYE & PULMONARY IRRITANTS...

/GUIDE 131P: FLAMMABLE LIQUIDS-TOXIC/ Health: TOXIC; may be fatal if inhaled, ingested or absorbed through skin. Inhalation or contact with some of these materials will irritate or burn skin and eyes. Fire will produce irritating, corrosive and/or toxic gases. Vapors may cause dizziness or suffocation. Runoff from fire control or dilution water may cause pollution. /Methacrylaldehyde; Methacrylaldehyde, inhibited; Methacrylaldehyde, stabilized/|/GUIDE 131P: FLAMMABLE LIQUIDS-TOXIC/ Fire or Explosion: HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames. Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapor explosion and poison hazard indoors, outdoors or in sewers. Those substances designated with a "P" may polymerize explosively when heated or involved in a fire. Runoff to sewer may create fire or explosion hazard. Containers may explode when heated. Many liquids are lighter than water. /Methacrylaldehyde; Methacrylaldehyde, inhibited; Methacrylaldehyde, stabilized/|/GUIDE 131P: FLAMMABLE LIQUIDS-TOXIC/ Public Safety: CALL Emergency Response Telephone Number ... . As an immediate precautionary measure, isolate spill or leak area for at least 50 meters (150 feet) in all directions. Keep unauthorized personnel away. Stay upwind. Keep out of low areas. Ventilate closed spaces before entering. /Methacrylaldehyde; Methacrylaldehyde, inhibited; Methacrylaldehyde, stabilized/|/GUIDE 131P: FLAMMABLE LIQUIDS-TOXIC/ Protective Clothing: Wear positive pressure self-contained breathing apparatus (SCBA). Wear chemical protective clothing that is specifically recommended by the manufacturer. It may provide little or no thermal protection. Structural firefighters' protective clothing provides limited protection in fire situations ONLY; it is not effective in spill situations where direct contact with the substance is possible. /Methacrylaldehyde; Methacrylaldehyde, inhibited; Methacrylaldehyde, stabilized/|For more DOT Emergency Guidelines (Complete) data for METHACROLEIN (8 total), please visit the HSDB record page.

No person may /transport,/ offer or accept a hazardous material for transportation in commerce unless that person is registered in conformance ... and the hazardous material is properly classed, described, packaged, marked, labeled, and in condition for shipment as required or authorized by ... /the hazardous materials regulations (49 CFR 171-177)./|The International Air Transport Association (IATA) Dangerous Goods Regulations are published by the IATA Dangerous Goods Board pursuant to IATA Resolutions 618 and 619 and constitute a manual of industry carrier regulations to be followed by all IATA Member airlines when transporting hazardous materials.|The International Maritime Dangerous Goods Code lays down basic principles for transporting hazardous chemicals. Detailed recommendations for individual substances and a number of recommendations for good practice are included in the classes dealing with such substances. A general index of technical names has also been compiled. This index should always be consulted when attempting to locate the appropriate procedures to be used when shipping any substance or article.

... STRONG IRRITANT

Consult an expert! Remove all ignition sources. Ventilation. Personal protection: complete protective clothing including self-contained breathing apparatus. Do NOT let this chemical enter the environment. Do NOT wash away into sewer. Collect leaking and spilled liquid in sealable containers as far as possible. Absorb remaining liquid in sand or inert absorbent. Wash away remainder with plenty of water. Then store and dispose of according to local regulations.

Fireproof. Separated from strong oxidants, acids, bases and food and feedstuffs. Cooled. Keep in the dark. Well closed. Keep under inert gas. Store only if stabilized. Provision to contain effluent from fire extinguishing.

A harmful contamination of the air can be reached very quickly on evaporation of this substance at 20 °C.

The substance is irritating to the eyes, skin and respiratory tract.

Health effects of the substance have been investigated but none have been found

NO open flames, NO sparks and NO smoking. Closed system, ventilation, explosion-proof electrical equipment and lighting. Do NOT use compressed air for filling, discharging, or handling. Use non-sparking handtools.

PREVENT GENERATION OF MISTS!

Use ventilation, local exhaust or breathing protection.

Protective gloves. Protective clothing.

Wear safety spectacles, face shield or eye protection in combination with breathing protection.

| 3 - Materials that, under emergency conditions, can cause serious or permanent injury.| 3 - Liquids and solids that can be ignited under almost all ambient temperature conditions. Materials produce hazardous atmospheres with air under almost all ambient temperatures or, though unaffected by ambient temperatures, are readily ignited under almost all conditions.| 2 - Materials that readily undergo violent chemical changes at elevated temperatures and pressures.|W - No water: Materials that react violently or explosively with water.

Methacrolein has been reported to be released from gasoline exhaust(1). Methacrolein is formed from burning polyethylene which may occur in fire situations(2). Methacrolein emissions from a single-cylinder, production-type engine using isooctane fuel were 21 and less than 1 mole fraction with a 0.9 and 1.15 fuel-air equivalence ratio, respectively(3). Methacrolein has been detected as an emission from liquid floor wax(4). Methacrolein made up 1.6% of the total hydrocarbons released from a pulse flame combustor using methyl-t-butyl ether as fuel(5).

URBAN/SUBURBAN: Air samples from four urban sites in Stockholm contained methacrolein at the following average concentrations: 0.71, 0.19, 0.11, and 0.13 ppb(1).|RURAL/REMOTE: In a rural site, 12 km outside of Stockholm, the average methacrolein concentration was 0.06 ppb(1).

Methacrolein is released upon thermal degradation of steel protective paints (350 °C) at the following amounts: from primers, 4, 1, and 7 mg/cu m (special, chlorinated rubber and alkyds); and finishing paints, 10 mg/cu m (alkyd)(1).

LD50 Rat oral 0.14 g/kg /From table/|LD50 Rabbit skin 0.43 g/kg /From table/

ONE OF THE COMPOUNDS IDENTIFIED IN THE SMOKE PRODUCED BY BURNING OF SHIPBOARD MATERIAL WAS METHACROLEIN.|Found in exhaust from API #7 gasoline in concentrations of 1.6 ppm|Found in exhaust from API #8 gasoline in concentrations of 0.9 ppm|Methacrolein's production and use in copolymers(1), resins(1), and as an intermediate for the production of methacrylonitrile or methacrylic acid(2) may result in its release to the environment through various waste streams(SRC).

TERRESTRIAL FATE: Based on a recommended classification scheme(1), an estimated Koc value of 11.3(SRC), determined from an experimental water solubility(2) and a recommended regression-derived equation(3), indicates that methacrolein will have very high mobility in soil(SRC). Volatilization of methacrolein may be important from moist soil surfaces(SRC) given an estimated Henry's Law constant of 2.86X10-4 atm-cu m/mole, calculated from experimental values of vapor pressure(4) and water solubility(2), and from dry soil surfaces(SRC) based on an experimental vapor pressure of 155 mm Hg(4). Insufficient data are available to determine the rate or importance of biodegradation of methacrolein in soil(SRC).|AQUATIC FATE: Based on a recommended classification scheme(1), an estimated Koc value of 11.3(SRC), determined from an experimental water solubility(2) and a recommended regression-derived equation(3), indicates that methacrolein may not adsorb to suspended solids and sediment(SRC) in the water. Methacrolein may volatilize from water surfaces based on an estimated Henry's Law constant of 2.86X10-4 atm-cu m/mole(SRC), calculated from experimental values of vapor pressure(4) and water solubility(2). Estimated half-lives for a model river and model lake are 5 hours and 4 days, respectively(3,SRC). An estimated BCF value of 1.4(3,SRC), from an experimental water solubility(2), suggests that methacrolein will not bioconcentrate in aquatic organisms(SRC) according to a recommended classification scheme(5). Insufficient data are available to determine the rate or importance of biodegradation of methacrolein in water(SRC).|ATMOSPHERIC FATE: According to a suggested classification scheme(1), an experimental vapor pressure of 155 mm Hg at 25 °C(2) indicates that methacrolein will exist in the vapor phase in the ambient atmosphere. Vapor-phase methacrolein is degraded in the atmosphere by reaction with photochemically produced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be about 11.5 hours(3,SRC). Vapor-phase methacrolein is also degraded in the atmosphere by reaction with ozone(SRC); the half-life for this reaction in air is estimated to be about 10.5 days(4,SRC). Methacrolein reacts very quickly in air with oxygen forming peroxides and acids(5). Methacrolein is formed from the gas-phase reaction of ozone with isoprene with a formation yield of 0.387(6).

The rate constant for the vapor-phase reaction of methacrolein with photochemically produced hydroxyl radicals has been experimentally determined to be 3.35X10-11 cu cm/molecule-sec at 25 °C(1). This corresponds to an atmospheric half-life of about 11.5 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1,SRC). The rate constant for the vapor-phase reaction of methacrolein with ozone has been experimentally determined to be 1.12X10-18 cu cm/molecule-sec at 25 °C(2). This corresponds to an atmospheric half-life of about 10.2 days at an atmospheric concentration of 7X10+11 ozone molecules per cu cm(2,SRC). Methacrolein reacts very quickly in air with oxygen forming peroxides and acids(3). Methacrolein is formed from the gas-phase reaction of ozone with isoprene with a formation yield of 0.387 at 296 deg K at 740 torr total pressure(4).

An estimated BCF value of 1.4 was calculated for methacrolein(SRC), using an experimental water solubility of 50,000 mg/L(1) and a recommended regression-derived equation(2). According to a recommended classification scheme(3), this BCF value suggests that bioconcentration in aquatic organisms will not be an important fate process(SRC).

The Koc of methacrolein is estimated as approximately 11.3(SRC), using an experimental water solubility of 50,000 mg/L(1) and a regression-derived equation(2,SRC). According to a recommended classification scheme(3), this estimated Koc value suggests that methacrolein has very high mobility in soil(SRC).

The Henry's Law constant for methacrolein is estimated as 1.9X10-4 atm-cu m/mole(SRC) from its experimental values for vapor pressure, 155 mm Hg(1), and water solubility, 50,000 mg/l(2). This value indicates that methacrolein will volatilize from water surfaces(3,SRC). Based on this Henry's Law constant, the volatilization half-life from a model river (1 m deep, flowing 1 m/sec, wind velocity of 3 m/sec) is estimated as approximately 5 hours(3,SRC). The volatilization half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec) is estimated as approximately 4 days(3,SRC). Methacrolein's high vapor pressure(1) and Henry's Law constant(1,2,SRC) indicate that volatilization from dry and moist soil may occur(SRC).

Methacrolein has been qualitatively detected as a volatile component of Chickpea (Cicer arietinum L) seed(1).

Exposure to methacrolein may occur through dermal contact and inhalation(1).

Methacrolein has been qualitatively detected in one out of 12 samples of human adipose tissue from a 0-14 age group in the Southern Region(1).

Aldehydes are readily oxidized to organic acids, which, in turn, can serve as substrates for fatty acid oxidation pathways and the Krebs cycle. ... Oxidation of aldehydes is catalyzed by aldehyde dehydrogenase, which has been found in the brain, erythrocytes, liver, kidney, heart, and placenta. /Aldehydes/|... The detoxification of aldehydes can be seen to proceed basically via two routes: (1) an oxidation to yield readily metabolized acids; (2) inactivation by reaction with sulfhydryl groups, particularly glutathione. Under conditions that either deplete glutathione levels, or that result in an inhibition of aldehyde dehydrogenase (for example, Antabuse treatment), the acute and chronic effects of aldehyde toxicity might be more fully expressed. /Aldehydes/

Excerpt from ERG Guide 131P [Flammable Liquids - Toxic]: TOXIC; may be fatal if inhaled, ingested or absorbed through skin. Inhalation or contact with some of these materials will irritate or burn skin and eyes. Fire will produce irritating, corrosive and/or toxic gases. Vapors may cause dizziness or suffocation. Runoff from fire control or dilution water may cause pollution. (ERG, 2016)

Excerpt from ERG Guide 131P [Flammable Liquids - Toxic]: Ensure that medical personnel are aware of the material(s) involved and take precautions to protect themselves. Move victim to fresh air. Call 911 or emergency medical service. Give artificial respiration if victim is not breathing. Do not use mouth-to-mouth method if victim ingested or inhaled the substance; give artificial respiration with the aid of a pocket mask equipped with a one-way valve or other proper respiratory medical device. Administer oxygen if breathing is difficult. Remove and isolate contaminated clothing and shoes. In case of contact with substance, immediately flush skin or eyes with running water for at least 20 minutes. Wash skin with soap and water. In case of burns, immediately cool affected skin for as long as possible with cold water. Do not remove clothing if adhering to skin. Keep victim calm and warm. Effects of exposure (inhalation, ingestion or skin contact) to substance may be delayed. (ERG, 2016)

Fresh air, rest.

Remove contaminated clothes. Rinse skin with plenty of water or shower. Refer for medical attention .

First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.

METHACROLEIN WAS LESS CILIOSTATIC (IRRITATING TO TRACHEAL MUCOSA) THAN ACROLEIN.|The low molecular weight aldehydes, the halogenated aliphatic aldehydes, and the unsaturated aldehydes are particularly irritating. The mucus membranes of the nasal and oral passages and the upper respiratory tract are affected, producing a burning sensation, an increased ventilation rate, bronchial constriction, choking, and coughing. The eyes tear, and a burning sensation is noted on the skin of the face. During low exposures, the initial discomfort may abate after 5 to 10 minutes but will recur if exposure is resumed after an interruption. /Aldehydes/|...STRONG IRRITANT.

2-methylacrolein

The substance can be absorbed into the body by inhalation of its vapour, through the skin and by ingestion.

Cough. Sore throat. Burning sensation.

Redness. Pain.

Redness. Pain. Burns. Watering of the eyes.

Shipped with 0.1% hydroquinone, as polymerization inhibitor

Pesticide, fertilizer, and other agricultural chemical manufacturing|2-Propenal, 2-methyl-: ACTIVE|Development of more productive catalysts for propylene oxidation, which were not advantages for isobutylene oxidation, and failure of growth in the commercial use of methacrolein contributed to the discontinuance of the manufacture of methacrolein.

Fire Hazards -> Flammable - 3rd degree, Reactive - 2nd degree