The effect of apparent catalysis at different concentration of flexible nanoparticles (FN), (FN = CTABr|MX|H2O) of piperidine with phenyl salicylate ion when substituted sodium phenolate [MX] not equal 0 at 35 A degrees C is discussed in this paper. The observed data (k(obs) vs. [MX]) have been discussed quantitatively based on pseudophase micellar (PM) model. Such data treatment gives relative micellar binding constants of counterion X- and Br-(R (X) (Br) ) with FN. The effects of [MX] on the k(obs) have been coherence in terms of empirical equation and rheological data. The large catalytic effect of FN on the rate of piperidinolysis of PS- and rheological evidence of micellar structure correlate to the relative counterion binding constant, R (X) (Br) .