The effects of small organic additive on micellar catalysis

The effects of isopropyl alcohol, tert-butyl alcohol, isopentyl alcohol, be nzaldchyde on the first-order rate constant k(1) of the basic hydrolysis re action of 2,4-dinitrochlorobenzene in the solution of cetyltrimethylammoniu m bromide(CTAB) are studied. The results show that k(1) decreases with incr easing the concentration of small organic additive. It was found that the s maller the alcohol solubility in water and the larger the binding constant with the micelles, the faster the reaction rate decreases. The pseudophase ion-exchange model is applied to quantitatively treat the experimental data . The above results are consistent, with that obtained from dynamic light s cattering, and are interpreted in terms of the change in micellar structure .