CAS No.: 616-38-6
Other Names: DMC
Solid Content: 99.7%
Appearance: Transparent Liquid
Dimethyl carbonate (DMC) is an organic compound with the formula OC(OCH3)2. It is a colourless, flammable liquid. It is classified as a carbonate ester. This compound has found use as a methylating agent and more recently as a solvent that is exempt from the restrictions placed on most volatile organic compounds (VOCs) in the US. Dimethyl carbonate is often considered to be a green reagent.
In the US, dimethyl carbonate was exempted under the definition of volatile organic compounds (VOCs) by the U.S. EPA in 2009. Due to its classification as VOC exempt, dimethyl carbonate has grown in popularity and applications as a replacement for methyl ethyl ketone (MEK), tert-butyl acetate, and parachlorobenzotrifluoride. Dimethyl carbonate has an ester- or alcohol-like odor, which is more favorable to users than most hydrocarbon solvents it replaces. Dimethyl carbonate has an evaporation rate of 3.22 (butyl acetate = 1.0), which slightly slower than MEK (3.8) and ethyl acetate (4.1), and faster than toluene (2.0) and isopropanol (1.7). Dimethyl carbonate has solubility profile similar to common glycol ethers, meaning dimethyl carbonate can dissolve most common coating resins except perhaps rubber based resins. Hildebrand solubility parameter is 20.3 Mpa and Hansen solubility parameters are: dispersion = 15.5, polar = 3.9, H bonding = 9.7. Dimethyl carbonate is partially soluble in water up to 13%, however it is hydrolyzed in water-based systems over time to methanol and CO2 unless properly buffered. Dimethyl carbonate can freeze at same temperatures as water, it can be thawed out with no loss of properties to itself or coatings based on dimethyl carbonate.
Intermediate in polycarbonate synthesis
A very large captive use of dimethyl carbonate is for the production of diphenyl carbonate through transesterification with phenol. Diphenyl carbonate is a widely used raw material for the synthesis of bisphenol-A-polycarbonate in a melt polycondensation process. The most common route is described by Fukuoka, of the Japanese "Asahi Kasei" chemical corporation.
Alternative fuel additive
There is also interest in using this compound as a fuel oxygenate additive.
Item/Lot# Specification Typical
Content(%): 99.7% min. 99.97%
Moisture(%): 0.05 max. 0.01%
Methanol: 0.02% max. 0.002%
Color: 10 max. 5
200kg net plastic drums(16MT/20’FCL)