Subject dodecyl phase

Aliphatic and aromatic nucleophilic substitution reactions are also subject to micellar effects, with results consistent with those in other reactions. In the reaction of alkyl halides with CN and S Oj in aqueous media, sodium dodecyl sulfate micelles decreased the second-order rate constants and dodecyltrimethylammonium bromide increased them (Winters, 1965 Bunton, 1968). The reactivity of methyl bromide in the cationic micellar phase was 30 to 50 times that in the bulk phase and was negligible in the anionic micellar phase a nonionic surfactant did not significantly affect the rate constant for n-pentyl bromide with S2O3-. Micellar effects on nucleophilic aromatic substitution reactions follow similar patterns. The reaction of 2, 4-dinitrochlorobenzene or 2, 4-dinitrofluorobenzene with hydroxide ion in aqueous media is catalyzed by cationic surfactants and retarded by sodium dodecyl sulfate (Bunton, 1968, 1969). Cetyltrimethylammonium bromide micelles increased the reactivity of dinitrofluorobenzene 59 times, whereas sodium dodecyl sulfate decreased it by a factor of 2.5 for dinitrochlorobenzene, the figures are 82 and 13 times, respectively. A POE nonionic surfactant had no effect. 

All monomers 1 are quickly and completely polymerized when subjected to sufficiently reactive nucleophiles or radicals. However, the reactivity of 1 toward polymerization initiated thermally or photochemically with 300 nm light is clearly dependent on the length of Af-alkyl chain. In fact, 1(R = C12H25) is selectively converted to the homopolymer when mixtures of it and 1 (R = C2H5) are sonicated at 100 °C in water. The dodecyl derivative appears to quickly polymerize within suspended, insoluble aggregates and the soluble ethyl analog remains unchanged in the water phase. 

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