Acetonitrile

CAS RN: 75-05-8

Polymerization

A mixture of acetonitrile and sulfuric acid on heating (or self-heating) to 53 deg C underwent an uncontrollable exothermic reaction to 160 deg C in a few seconds. The presence of 28 mol% of sulfur trioxide reduces the initiation temperature to about 15 deg C. Polymerization of the nitrile is suspected.
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