In the presence of di--butyl nitroxide (DTBNO) polyfluorodiacylperoxides undergo rapid decomposition in -pentane or CClF2-CCl2F at −50 to +20°C. The reactions are first order in peroxide and DTBNO. On the basis of ESR observation of -butyl polyfluoroalkyl nitroxides as well as product analysis, it appears that the decomposition processes involve DTBNO inducedhomolysis of the peroxy bonds followed