Molecule of the Week

2,2’-Azobis(isobutyronitrile)

February 16, 2009

2,2’-Azobis(isobutyronitrile), or AIBN, is a commonly used initiator for free-radical reactions, including many polymerizations. Its preparation was first reported by Thiele and Heuser in 1896, and it has been used in polymerization since at least the 1940s. Its downsides are high toxicity (it decomposes to HCN in vivo), flammability, and the explosivity of its acetone solutions.