General Description
A clear colorless liquid. Slightly soluble in water and floats on water. Vapors heavier than air. Vapors irritate the eyes and respiratory system. Containers must be heavily insulated or shipped under refrigeration. An inhibitor such as hydroquinone, hydroquinone methyl ester and dimethyl t-butylphenol is added to keep the chemical from initiating polymerization. The chemical may polymerize exothermically if heated or contaminated with strong acid or base. If the polymerization takes place inside a container, the container may rupture violently. Used to make plastics.
Reactivity Profile
METHYL METHACRYLATE MONOMER(80-62-6), may polymerize if contaminated or subjected to heat. If polymerization takes place in a container, the container is subject to violent rupture. Oxidizes readily in air to form unstable peroxides that may explode spontaneously [Bretherick 1979. p.151-154, 164]. Peroxides may also initiate exothermic polymierization of the bulk material [Bretherick 1979. p. 160]. Benzoyl peroxide was weighed into a beaker that had previously been rinsed with methyl methacrylate. The peroxide catalyzed polymerization of the methyl methacrylate and the build-up of heat ignited the remaining peroxide [MCA Case History 996. 1964].
Air & Water Reactions
Highly flammable. Very slightly soluble in water.
Hazard
Flammable, dangerous fire risk, explosivelimits in air 2.1–12.5%. Eye and upper respiratorytract irritant, body weight effects, and pulmonaryedema. Questionable carcinogen.
Health Hazard
Irritation of eyes, nose, and throat. Nausea and vomiting. Liquid may cause skin irritation.
Potential Exposure
Virtually all of the methyl methacrylate monomer produced is used in the production of
polymers, such as surface coating resins; plastics (Plexiglas
and Lucite); ion exchange resins; and plastic dentures.
Fire Hazard
Behavior in Fire: Vapor is heavier than air and may travel a considerable distance to a source of ignition and flash back. Containers may explode in fire or when heated because of polymerization.
First aid
If this chemical gets into the eyes, remove any
contact lenses at once and irrigate immediately for at least
15 minutes, occasionally lifting upper and lower lids. Seek
medical attention immediately. If this chemical contacts the
skin, remove contaminated clothing and wash immediately
with soap and water. Seek medical attention immediately.
If this chemical has been inhaled, remove from exposure,
begin rescue breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR if
heart action has stopped. Transfer promptly to a medical
facility. When this chemical has been swallowed, get
medical attention. Give large quantities of water and induce
vomiting. Do not make an unconscious person vomit.
Shipping
UN1247 Methyl methacrylate monomer,
stabilized, Hazard Class: 3; Labels: 3-Flammable liquid.
Incompatibilities
Vapor may form explosive mixture
with air. Reacts in air to form a heat-sensitive explosive
product @ 60C. Incompatible with nitrates, oxidizers,
peroxides, strong acids; strong alkalis; oxidizers,
reducing agents; amines, moisture. Contact with benzoyl
peroxide may cause ignition, fire and explosion. May
polymerize if subjected to heat, polymerization catalysts
e. g., azoisobutyronitrile, dibenzoyl peroxide; di-tert-butyl
peroxide, propionaldehyde); strong oxidizers; or ultraviolet light. May contain an inhibitor, such as hydroquinone.
Description
Methyl methacrylate is an organic compound with the formula CH2=C(CH3)COOCH3. This colourless liquid, the methyl ester of methacrylic acid (MAA) is a monomer produced on a large scale for the production of poly(methyl methacrylate) (PMMA).
Chemical Properties
Methyl 2-methyl-2-propenoate has an acrid, penetrating odor. In another report this compound is reported to possess
a sharp, fruity odor
Chemical Properties
Methyl methacrylate is a colorless liquid.
Acrid, fruity odor. The odor threshold is 0.050.083 ppm
Chemical Properties
Methyl methacrylate is a methyl ester of methacrylic acid. It is a colourless, volatile liquid with an acrid fruity odour. It has a relatively high vapour pressure (4 kPa at 20°C), moderate water solubility (15.8 g/litre), and a low log octanol/water partition coefficient (Kow = 1.38) . Methyl methacrylate is typically 99.9% pure and contains small amounts of inhibitor to retard polymerization.
Waste Disposal
Consult with environmental
regulatory agencies for guidance on acceptable disposal
practices. Generators of waste containing this contaminant
(≥100 kg/mo) must conform to EPA regulations governing
storage, transportation, treatment, and waste disposal.
Incineration may be allowed.
Physical properties
Clear, colorless liquid with a penetrating, fruity odor. An experimentally determined odor
threshold concentration of 210 ppbv was reported by Leonardos et al. (1969). Experimentally
determined detection and recognition odor threshold concentrations were 200 μg/m3 (49 ppbv) and
1.4 mg/m3 (340 ppbv), respectively (Hellman and Small, 1974).
Uses
- Methyl methacrylate is a volatile synthetic chemical that is used principally in the production of cast acrylic sheet, acrylic emulsions, and moulding and extrusion resins.
- In the manufacture of methacrylate resins and plastics. Methyl methacrylate is transesterified into higher methacrylates such as n-butyl methacrylate or 2-ethylhexyl methacrylate.
- methyl methacrylate monomer is used in the production of methylmethacrylate polymers and copolymers, polymers and copolymers are also used in waterborne, solvent, and undissolved surface coatings, adhesives, sealants, leather and paper coatings, inks, floor polishes, textile finishes, dental prostheses, surgical bone cements, and leaded acrylic radiation shields and in the preparation of synthetic fingernails and orthotic shoe inserts. Methyl methacrylate is also used as a starting material to manufacture other esters of methacrylic acid.
- Granules for injection and extrusion blow moulding which for their outstanding optical clarity, weathering and scratch resistance are used in lighting, office equipment and electronics (cell phone displays and hi-fi equipment), building and construction (glazing and window frames), contemporary design (furniture, jewellery and tableware), cars and transportation (lights and instrument panels), health and safety (jars and test tubes) and household appliances (microwave oven doors and mixer bowls).
- Impact modifiers for clear rigid polyvinyl chloride.
Uses
Methyl methacrylatec is used in acrylic bone cements used in orthopedic surgery; in the production of acrylic polymers, polymethylmethacrylate and
copolymers used in acrylic surface coatings; in the manufaeture of emulsion polymers; in the modification of unsaturated
polyester resins; in the production of higher methacrylate, acrylic fibers, acrylic film, inks, radiation-polymerized impregnants for
wood, and solvent-based adhesives and binders; as an impact modifier of PVC; in medicinal spray adhesives; in nonirritant
bandage solvents; in dental technology as ceramic filler or cement; to coat corneal contact lenses; in intraocular lenses, artificial nails,
and hearing aids; as a monomer for polymethaerylate resins; in the impregnation of concretc.
Uses
The principal application, consuming approximately 80% of the MMA, is the manufacture of poly methyl methacrylate acrylic plastics (PMMA). Methyl methacrylate is also used for the production of the co-polymer methyl methacrylate-butadiene-styrene (MBS), used as a modifier for PVC. Another application is as cement used in total hip replacements as well as total knee replacements. Used as the "grout" by orthopedic surgeons to make the bone inserts fix into bone, it greatly reduces post-operative pain from the insertions but has a finite lifespan. Typically the lifespan of methyl methacrylate as bone cement is 20 years before revision surgery is required. Cemented implants are usually only done in elderly populations that require more immediate short term replacements. In younger populations, cementless implants are used because their lifespan is considerably longer. Also used in fracture repair in small exotic animal species using internal fixation.
Definition
ChEBI: An enoate ester having methacrylic acid as the carboxylic acid component and methanol as the alcohol component.
Definition
methyl methacrylate: An ester ofmethacrylic acid (2-methylpropenoicacid), CH2:C(CH3)COOCH3, used inmaking methacrylate resins.
Definition
The methyl ester
of methacrylic acid. The compound is used
in the manufacture of a number of acrylic
polymers, such as Plexiglas (polymethylmethacrylate).
Preparation
Prepared by the esterification of methacrylamide sulfate with methanol.
Aroma threshold values
Detection at 0.024 to 0.058 ppm (water); recognition at 0.7 to 1.4 mg/m3 (air); detection at 0.2 to 0.62 mg/m3.
Flammability and Explosibility
Flammable
Industrial uses
Initiators for methyl methacrylate polymerization include AIBN, dilauroyl peroxide (LPO), and 2,2'-Azobis[2-(2-imidazolin-2- yl)propane].
Carcinogenicity
In several lifetime animal studies,
there was no evidence that methyl methacrylate is
carcinogenic.
Environmental Fate
Chemical/Physical. Polymerizes easily (Windholz et al., 1983). Methyl methacrylate undergoes
nucleophilic attack by OH ions in water (hydrolysis) resulting in the formation of methacrylic acid
and methanol (Kollig, 1993). Hydrolysis occurs at a rate of 171/M?h at 25 °C (Sharma and
Sharma, 1970). No measurable hydrolysis was observed at 85.0 °C (pH 7) and 25 °C (pH 7.07).
Hydrolysis half-lives of 9 and 134 min were observed at 66.0 °C (pH 9.86) and 25.0 °C (pH 11.3),
respectively (Ellington et al., 1987).
Purification Methods
Wash the ester twice with aqueous 5% NaOH (to remove inhibitors such as hydroquinone) and twice with water. Dry it with CaCl2, Na2CO3, Na2SO4 or MgSO4, then with CaH2 under nitrogen under reduced pressure. The distillate is stored at low temperatures and redistilled before use. Prior to distilling, inhibitors such as hydroquinone (0,004%), .-naphthylamine (0.2%) or di--naphthol are sometimes added. Also purify it by boiling with aqueous H3PO4 solution and finally with saturated NaCl solution. It is dried for 24hours over anhydrous CaSO4, distilled at 0.1mm Hg at room temperature and stored at -30o [Albeck et al. J Chem Soc, Faraday Trans 1 1 1488 1978]. [Beilstein 2 II 398, 2 III 1279, 2 IV 1519.]
Toxicity evaluation
The mitochondria are regarded as the main intracellular
target of MMA. If isolated rat liver mitochondria are incubated
with MMA, oxygen consumption increases. This is
the result of an uncoupling of the mitochondrial respiratory
chain, as seen from the expected influence on state 4
and state 3 respiration. State 4 respiration is stimulated. As
has been reported for organic solvents, MMA attacks
complex I of the respiratory chain close to the rotenonebinding
site. This means that substrates which are oxidized
in conjunction with nicotinamide adenine dinucleotide
inhibit the flow of electrons and thus also ATP synthesis.
Unlike classical uncouplers, MMA stimulates the Mg2+-
dependent ATPase bound to the inner mitochondrial membrane.
Structural changes in the inner membrane, as found
with nonionic detergents, were observed by electron micro
scopy. The release of enzymes indicates disintegration of
the membrane.
