# Tuning Rheochaos by Temperature in Wormlike Micelles

Ganapathy, Rajesh and Sood, AK (2006) Tuning Rheochaos by Temperature in Wormlike Micelles. In: Langmuir, 22 (26). 11016 -11021.

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## Abstract

We investigate the critical role played by the mean micellar length during the route to rheochaos for wormlike micellar gels of surfactant cetyltrimethylammonium tosylate in the presence of salt sodium chloride that show coupling of flow to concentration fluctuations. To this end, we have carried out stress/shear rate relaxation experiments at a fixed shear rate/stress but at different temperatures to take the sample through the route to rheochaos. We see the type-II intermittency route to rheochaos in stress relaxation measurements and the type-III intermittency route to rheochaos in shear rate relaxation measurements.Wehave also carried out linear rheology measurements at different temperatures to estimate the mean micellar length $\bar{L}$, the reptation time $\tau_{rep}$, and the breaking time $\tau_{break}$. It is shown that $\bar{L}$ changes by $\approx 58\%$, as the sample goes through the route to rheochaos.

Item Type: Journal Article Copyright of this article belongs to American Chemical Society. Division of Physical & Mathematical Sciences > Physics 11 Aug 2008 19 Sep 2010 04:49 http://eprints.iisc.ernet.in/id/eprint/15519