What is "vinylacetylene"

n. (context organic compound English) A dimer of acetylene ''butenyne'' CH₂=CH-C≡CH used in the manufacture of some polymers

Vinylacetylene is the organic compound with the formula CH. The colourless gas was once used in the polymer industry. It is composed of both alkyne and alkene groups.

Vinylacetylene is extremely dangerous because in high enough concentrations (typically > 30 mole percent, but pressure dependent) it can auto-detonate (explode without air being present) especially at elevated pressures, such as those seen in chemical plants processing C4 hydrocarbons. An example of such an explosion occurred at a Union Carbide plant in Texas City in 1969.