| Chemical Properties | Propylene glycol monomethyl ether is a colorless liquid with a sweet ether-likeodor and bitter taste. It is soluble in water, ether, acetone, and benzene. |
| Uses | 1-Methoxy-2-propanol is primarily used in the manufacture oflacquers and paints, as an anti-freeze in industrial engines, a tailing agent for inksused on very high-speed presses, a coupling agent for resins and dyes in waterbasedinks, and a solvent for celluloses, acrylics, dyes, inks, and stains. It is alsoused in cleaning products such as glass and rug cleaners, carbon and greaseremovers, and paint and varnish removers; and in pesticide formulations as asolvent for applications to crops and animals. |
| Air & Water Reactions | Highly flammable. Soluble in water. Oxidizes readily in air to form unstable peroxides that may explode spontaneously [Bretherick 1979 p.151-154, 164]. |
| Reactivity Profile | 1-Methoxy-2-propanol is a methoxy alcohol derivative. The ether being relatively unreactive. Flammable and/or toxic gases are generated by the combination of alcohols with alkali metals, nitrides, and strong reducing agents. They react with oxoacids and carboxylic acids to form esters plus water. Oxidizing agents convert them to aldehydes or ketones. Alcohols exhibit both weak acid and weak base behavior. They may initiate the polymerization of isocyanates and epoxides. |
| Hazard | Flammable, moderate fire risk. TLV: 100ppm; STEL 150 ppm. |
| Health Hazard | VAPOR: Irritating to eyes, nose, and throat. LIQUID: Irritating to skin and eyes. |
| Fire Hazard | FLAMMABLE. Flashback along vapor trail may occur. Vapor may explode if ignited in an enclosed area. |
| Safety Profile | Moderately toxic byintravenous route. Mildly toxic by ingestion,inhalation, and skin contact. Humansystemic effects by inhalation: generalanesthesia, nausea. A skin and eye irritant.An experimental teratogen. Many glycolethers have dangerous human reproductiveeffects. Very dangerous fire hazard whenexposed to heat or flame; can react withoxidizing materials. To fight fire, use foam,CO2, dry chemical. When heated todecomposition it emits acrid smoke andirritating fumes. Used as a solvent and insolvent-sealing of cellophane. See alsoGLYCOL ETHERS and ETHYLENEGLYCOL MONOMETHYL ETHER. |
| Synthesis | 1-methoxy-2-propanol is prepared by reacting propylene oxide with methanol in the presence of a racemic catalyst which comprises an asymmetric polydentate (tetradentate) ligand complexed with a metal atom, where the complex has an approximately planar geometry. |
| Potential Exposure | Propylene glycol monomethyl ether isused as a solvent for coatings; cellulose esters and acrylics;acrylics dyes; inks, and stains. It may also be used asa heat-transfer fluid. |
| Shipping | UN3092 1-Methoxy-2-propanol, Hazard Class: 3;Labels: 3-Flammable liquid. |
| Advantages | 1-Methoxy-2-propanol has been used as an antifreeze material, principally in ebullient cooling systems and in some heavy-duty diesel engines. Because an azeotrope is formed between 1-methoxy-2-propanol and water, freeze protection also is provided in the vapor phase in ebullient cooling applications. On the other hand, it is more volatile and is more readily expelled along with water vapor through the crankcase vent system. It also maintains lower metal temperatures than comparative glycolbased coolants. This was an advantage in rotary engines. |
| Toxicity evaluation | Contact irritates skin, eyes and mucous membranes. Prolonged exposure to vapors may cause coughing, shortness of breath, dizziness and intoxication. Vapors heavier than air. Used as a solvent and as an antifreeze agent. The oral LD50 of rats was 6.6g/kg. The skin irritation is not obvious, but the toxic dose can be absorbed through the skin. The main manifestations of animal poisoning were inhibition and incomplete anesthesia. Half of the rats died when they were exposed to steam concentration of 40.18g/m3 for 5 ~ 6 hours. the impact of 1-methoxypropanol-2 (MEP) for the stimulation of an inflammatory response in human respiratory mucosa, we exposed 22 primary cell cultures of nasal respiratory epithelia of healthy individuals to MEP concentrations at the level of the German MAK-value (100ppm) and to the 10-fold concentration (1000ppm). |
| Incompatibilities | Vapor may form explosive mixturewith air. Incompatible with oxidizers (chlorates, nitrates,peroxides, permanganates, perchlorates, chlorine, bromine,fluorine, etc.); contact may cause fires or explosions. Keepaway from alkaline materials, strong bases, strong acids,oxoacids, epoxides, acid chlorides, acid anhydrides, isocya-nates, aluminum, and copper. Hygroscopic (i.e., absorbsmoisture from the air). May slowly form reactive peroxidesduring prolonged storage or on exposure to air and light. |
| Toxics Screening Level | The initial threshold screening level (ITSL) for exposure to propylene glycol monomethyl ether (PGME) is 3,700 μg/m3 (1-hour averaging time) and 2,000 μg/m3(annual averaging time). |
| Waste Disposal | Dissolve or mix thematerial with a combustible solvent and burn in a chemicalincinerator equipped with an afterburner and scrubber.All federal, state, and local environmental regulations mustbe observed. |
