Methylal

  • Dimethoxymethane
  • Formal
  • Formaldehyde dimethyl acetal
Formula CH2(OCH3)2
Structure
Description Colorless, clear, volatile liquid, chloroform-like odor.
Uses In perfumery, manufacture artificial resins, reaction medium for grignard & reppe reactions.

Registry Numbers and Inventories.
CAS 109-87-5
EC (EINECS/ELINCS) 203-714-2
EC Class highly flammable
EC Risk Phrase R 11 36/37
EC Safety Phrase S 9 16 26 33
RTECS PA8750000
RTECS class Primary Irritant
UN (DOT) 1234
Merck 12,6093
Beilstein/Gmelin 1697025
Beilstein Reference 4-01-00-03026
Swiss Giftliste 1 G-2421
Canada DSL/NDSL DSL
US TSCA Listed
Austrailia AICS Listed
New Zealand Listed
Japan ENCS (MITI) Listed
Korea ECL Listed

Properties.
Formula C3H8O2
Formula mass 76.10
Melting point, °C -105
Boiling point, °C 42
Vapor pressure, mmHg 400 (20 C)
Vapor density (air=1) 2.6
Saturation Concentration 4.3 x 10(5) ppm (43%) at 20 C (calculated)
Evaporization number 0.88 (butyl acetate = 1)
Critical temperature 215
Density 0.821 g/cm3 (20 C)
Solubility in water 33 g/100 mL
Viscosity 0.33 cP 30 C
Surface tension 21.1 g/s2
Refractive index 1.3589 (20 C)
Heat of fusion 7.95 kJ/mol
Heat of vaporization 30.0 kJ/mol
Heat of combustion -1936 kJ/mol

Hazards and Protection.
Storage Keep away from heat, sparks, and flame. Keep away from sources of ignition. Do not store in direct sunlight. Store in a tightly closed container. Store in a cool, dry, well-ventilated area away from incompatible substances. Flammables-area.
Handling Ground and bond containers when transferring material. Use spark-proof tools and explosion proof equipment. Avoid contact with eyes, skin, and clothing. Empty containers retain product residue, (liquid and/or vapor), and can be dangerous. Take precautionary measures against static discharges. Keep container tightly closed. Avoid contact with heat, sparks and flame. Avoid ingestion and inhalation. Use with adequate ventilation. Wash clothing before reuse. This product may be under pressure; cool before opening. Do not use if the material has evaporated to dryness. Do not pressurize, cut, weld, braze, solder, drill, grind, or expose empty containers to heat, sparks or open flames.
Protection Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves to prevent skin exposure. Clothing: Wear appropriate protective clothing to prevent skin exposure.
Respirators A respiratory protection program that meets OSHA's 29 CFR 1910.134 and ANSI Z88.2 requirements or European Standard EN 149 must be followed whenever workplace conditions warrant a respirator's use.
Small spills/leaks Absorb spill with inert material, (e.g., dry sand or earth), then place into a chemical waste container. Avoid runoff into storm sewers and ditches which lead to waterways. Clean up spills immediately, using the appropriate protective equipment. Remove all sources of ignition. Use a spark-proof tool. Provide ventilation. A vapor suppressing foam may be used to reduce vapors.
Disposal code 1
Stability Stable at room temperature in closed containers under normal storage and handling conditions.
Incompatibilities Strong oxidizing agents.
Decomposition Carbon monoxide, carbon dioxide, formaldehyde.

Fire.
Flash Point,°C -18
Autoignition, °C 235
Upper exp. limit, % 12.6
Lower exp. limit, % 3.6
Fire fighting Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion. Use water spray to keep fire-exposed containers cool. Water may be ineffective. Material is lighter than water and a fire may be spread by the use of water. Containers may explode in the heat of a fire. May polymerize explosively when involved in a fire. Runoff to sewer may create fire or explosion hazard. Extinguishing media: For small fires, use dry chemical, carbon dioxide, water spray or alcohol-resistant foam. For large fires, use water spray, fog, or alcohol-resistant foam. Use water spray to cool fire-exposed containers.
Fire potential FLAMMABLE.
Hazards Irritating gases may be produced when heated. Containers may explode in fire. Flashback along vapor trail may occur. Vapor may explode if ignited in an enclosed area. Irritating formaldehyde gas may be present in smoke.
Combustion products Fire may produce irritating, corrosive and/or toxic gases.
NFPA Health 1
  Flammability 3  
  Reactivity 1  

Health.
Exposure limit(s) TLV: 1000 ppm; 3110 mg/m3 (ACGIH 1991-1992). OSHA PEL: TWA 1000 ppm (3100 mg/m3) NIOSH REL: TWA 1000 ppm (3100 mg/m3) NIOSH IDLH: 2200 ppm LEL
Poison_Class 4
Exposure effects Prolonged or repeated skin contact may cause defatting and dermatitis. May cause liver and kidney damage. Prolonged exposure may produce a narcotic effect. Effects may be delayed.
   Ingestion May cause gastrointestinal irritation with nausea, vomiting and diarrhea. Ingestion of large amounts may cause CNS depression.
   Inhalation Effects may be delayed. Causes respiratory tract irritation. May cause dizziness, incoordination, and unconsciousness. Aspiration may lead to pulmonary edema. Vapors may cause dizziness or suffocation. Can produce delayed pulmonary edema. May cause burning sensation in the chest. Animals exposed to high concentrations have shown liver, kidney, heart , and lung abnormalities.
   Skin Causes skin irritation. Prolonged and/or repeated contact may cause defatting of the skin and dermatitis. Causes redness and pain. May cause cyanosis of the extremities.
   Eyes Causes eye irritation. Causes redness and pain. May cause chemical conjunctivitis and corneal damage.

First aid
 
   Ingestion Never give anything by mouth to an unconscious person. Get medical aid. Do NOT induce vomiting. If conscious and alert, rinse mouth and drink 2-4 cupfuls of milk or water. Wash mouth out with water.
   Inhalation Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical aid. DO NOT use mouth-to-mouth respiration.
   Skin Get medical aid. Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Wash clothing before reuse.
   Eyes Immediately flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid.

Transport.
UN number 1234
Response guide 127
Hazard class 3
Packing Group II  
USCG CHRIS Code MTF  
USCG Compatatibility Group 41 Ethers
HS Code 2911 00 00  
Std. Transport # 4908222