Boiling point -34 °C Pubchem 10037 | Appearance Colorless gas | |
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Propadiene is the organic compound with the formula H2C=C=CH2. It is the simplest allene or compound with two adjacent C=C double bonds, and can also be identified as allene. As a constituent of MAPP gas, it has been used as a fuel for specialized welding.
Production and equilibrium with methylacetylene
Allene exists in equilibrium with methylacetylene (or propyne), the mixture sometimes being called MAPD for methylacetylene-propadiene:
H3CC≡CH ⇌ H2C=C=CH2
for which Keq = 0.22 at 270 °C or 0.1 at 5 °C. MAPD is produced as a side product, often an undesirable one, of cracking propane to produce propene, an important feedstock in the chemical industry. MAPD interferes with the catalytic polymerization of propene.
References
Propadiene Wikipedia(Text) CC BY-SA