title: Worm-like micelles of CTAB and sodium salicylate under turbulent flow.
abstract: Polymers with high molecular weight and worm-like micelles are drag-reducing agents under turbulent flow. However, in contrast to the polymeric systems, the worm-like micelles do not undergo mechanical degradation due to the turbulence, because their macromolecular structure can be spontaneously restored. This very favorable property, together with their drag-reduction capability, offer the possibility to use such worm-like micelles in heating and cooling systems to recirculate water while expending less energy. The formation, growth, and stability of worm-like micelles formed by cetyltrimethylammonium bromide (CTAB) and sodium salicylate (NaSal) were investigated using the self-fluorescence of salicylate ions and the ability of the giant micelles to promote hydrodynamic drag reduction under turbulent flow. The turbulence in solutions of CTAB-Sal was produced within the double-gap cell of a rotational rheometer. Detailed diagrams were obtained for different ratios of Sal and CTAB, which revealed transitions associated with the thermal stability of giant micelles under turbulent flow.
authors.affiliation: Department of Physical-Chemistry, Institute of Chemistry, University of Campinas - UNICAMP, P.O. Box 6154, 13084-862, Campinas, SP, Brazil.
authors.forename: Roberta K
authors.initials: RK
authors.lastname: Rodrigues
authors.forename: Marcelo A
authors.initials: MA
authors.lastname: da Silva
authors.forename: Edvaldo
authors.initials: E
authors.lastname: Sabadini