Small-angle neutron scattering from tetradecyltrimethylammonium bromide inNaBr aqueous solutions

Small angle neutron scattering was used to characterise quantitatively the micelles of tetradecyltrimethylammonium bromide at a concentration of about 50 mM in aqueous (D2O) solutions with added salt NaBr. It is shown that th e shape of the micelles changes from spheres to rod-like particles with inc reasing electrolyte concentration. The interparticle interaction becomes ef fectively screened if the salt concentration exceeds 0.1 M leading to a rem arkable growth of the cylindrical micelles. Moreover, it is demonstrated th at there is a gradual dehydration of the micelles due to the addition of Na Br. (C) 2001 Elsevier Science B.V. All rights reserved.