Micellar catalysis of radical reactions. A spin trapping study

The reaction of surfactant radicals and the spin trap 2-methyl-2-nitrosopropane has been investigated. Sodium dodecyl sulfate and sodium octyl sulfate show no spin adduct when surfactant and spin trap are irradiated with 60Co at concentrations below their critical micelle concentration (CMC). At concentrations above the cmc a nitroxide is formed from the reaction of the trap and a secondary surfactant radical produced via hydroxyl radical attack on the hydrocarbon chain. The micellar catalytic effect and the site of hydroxyl radical attack are discussed