NETWORK PROPERTIES OF SEMIDILUTE AQUEOUS KBR SOLUTIONS OF CETYLTRIMETHYLAMMONIUM BROMIDE

Elastic and quasi-elastic light scattering and rheological (shear viscosity, viscoelastic relaxation time) measurements have been performed on cetyltrimethylammonium bromide (CTAB) aqueous solutions in the presence of 0. 1 or 0. 25 KBr, at surfactant concentrations where the micelles are very elongated, and between 20 and 60 degree C. The results provide additional evidence for the previously noted analogy of behavior between concentrated solutions of very elongated micelles and solutions of polymer chains in the semidilute range where the chains are entangled. The results confirm that the micelles keep growing when the surfactant concentration exceeds the cross-over concentration where the micellar domains overlap.