| 초록 |
In this article, we considered shear-induced microstructure and rheological behavior ofmicellar solutions of cationic surfactant, cetylpyridinium chloride (CPC) in the presence ofa structure-forming additive, sodium salicylate (NaSal). Shear viscosity, shear moduli andflow birefringence were measured as functions of the surfactant and additive concentrations.In the presence of NaSal, the micellar solution exhibited the nonlinear rheological behaviordue to the formation of supramolecular structures when the molar ratio of NaSal to CPC exceededa certain threshold value. Flow birefringence probed the change in micelle alignment undershear flow. At low shear rates, the flow birefringence increased as the shear rate increased.On the other hand, fluctuation of flow birefringence appeared from the shear rate nearthe onset of shear thickening, which was caused by shear-induced coagulation or aggregation.These results were confirmed by the SEM images of in situ gelified micelle structure throughsol-gel route. |
