Polyoxymethylene Dimethyl Ethers

Basics

• Often abbreviated as PODE ‘’’p’’’oly’’’O’’’xymethylene’’’d’’’ymethl’’’e’’’ther, OMEx ( ‘’’O’’’xy’’’m’’’ethyle dimethyl ‘’’e’’’thers where X is the chain length) or more infrequently POMDME
• Polyoxymethylene Dimethyl Ethers are a class of Oligomers (Something in between a compund and a giant chain polymer) related to DME
• They have the advantage of being liquid at STP
  • Thus they can be used with more conventional fuel system/blended into Diesel Fuel (in a similar manner to how Biodiesel is currently blended, or how Ethanol and other Alcohol Fuels are blended into Gasoline
• More complex to synthesize than Methanol or DME however

Oligomers

OME₁

• Called Dimethoxymethane
  • Also known as “Formaldehyde dimethylacetal”
  • C₃H₈O₂
  • (CH3O)2CH2
  • (CH₃O)₂CH₂
• Properties (as of now pulled from wikipedia):
  • Density: 0.8593 g cm−3 (at 20 °C)
  • Melting Point −105 °C
  • Boiling Point 42 °C
  • Vapor Presssure 330 mmHg (20 °C)
    • Need to see how this compares to how RVP is measured
  • NIOSH (US health exposure limits):
    • PEL TWA of 1000 ppm
    • REL TWA of 1000 ppm
    • IDLH TWA of 2200 ppm
    • GRANTED as with more novel/niche chemicals take this with a grain of salt
    • ALSO need to see if standard 5 Gas Monitors / LEL + VOC meters will accurately pick up the presence + concentration of this

Synthesis

• As Per A 2017 Review in “Applied Catalysis” Titled “ Catalytic synthesis of polyoxymethylene dimethyl ethers (OME): A review
  • Formaldehyde -> Trioxane (TRI) or Paraformaldehyde (PF) ->
  • Methanol + Formaldehyde (Or Formalin ; need to see if it needs to be Anhydrous ) -> OME1 (aka Dimethoxymethane )

Internal Links

• DME
• Diesel Fuel Additives
• POM (Plastic) (Related compound albeit way longer Chain Length )

External Links

• The Wikipedia Page on Polyoxymethylene Dimethyl Ethers
• A June 2024 Paper in “International Journal of Engine Research” Titled “Development of a reduced primary reference fuel – oxymethylene dimethyl ether (PRF-OMEx) mechanism for diesel engine applications“
• A 2010 Study Titled “ Poly(oxymethylene) dimethyl ethers as components of tailored diesel fuel: Properties, synthesis and purification concepts”
• A 2020 Study Titled “ Nitrogen Oxide Reduction Potentials Using Dimethyl Ether and Oxymethylene Ether in a Heavy-Duty Diesel Engine”
• A 2022 Study Titled “Heat release peculiarities of polyoxymethylene dimethyl ether 1 – Part I: Effect of initial thermochemical conditions”
• A 2022 Study Titled “ The effect of poly(oxymethylene) dimethyl ethers (PODE3) on soot formation in ethylene/PODE3 laminar coflow diffusion flames”
• “Critical solubility of dimethyl ether (DME)+diesel fuel and dimethyl carbonate (DMC)+diesel fuel”