Portal de Periódicos da CAPES

Light scattering investigations of the behavior of semidilute aqueous micellar solutions of cetyltrimethylammonium bromide: Analogy with semidilute polymer solutions

1985; Elsevier BV; Volume: 105; Issue: 2 Linguagem: Inglês

10.1016/0021-9797(85)90327-3

1095-7103

S. J. Candau, Ernest Hirsch, R. Zana,

Spectroscopy and Quantum Chemical Studies

Micellar solutions of cetyltrimethylammonium bromide (CTAB) in H2O-0.1 M KBr and H2O-0.25 M KBr have been investigated up to high concentrations, in the semidilute range, by means of elastic and quasielastic light scattering, with particular emphasis on the effect of the scattering wave vector on both the intensity of scattered light and collective translational diffusion coefficient. All the results could be intepreted in terms of theories used to describe the behavior of solutions of long flexible polymer chains in the semidilute range, i.e., when the polymer coils overlap forming a network. The concentration dependences of the scattered intensity and collective diffusion coefficient extrapolated to zero wave vector were found to follow the power laws derived for semidilute polymer solutions in good solvent. These results give a strong support to a model of long flexible entangled micelles in aqueous CTAB solutions in the presence of 0.1 or 0.25 M KBr.