Suppression of the Rayleigh–Plateau instability on a vertical fibre coated with wormlike micelle solutions

• Published in: Soft matter Vol. 9; no. 32; pp. 7787 - 7796
• Main Authors: Boulogne, F., Fardin, M. A., Lerouge, S., Pauchard, L., Giorgiutti-Dauphiné, F.
• Format: Journal Article
• Language: English
• Published: Royal Society of Chemistry 01.01.2013
• Subjects: Coating; Condensed Matter; Estimating; Fibre; Fluid Dynamics; Instability; Mathematical models; Micelles; Physics; Soft Condensed Matter; Stability; Stability analysis
• ISSN: 1744-683X; 1744-6848
• DOI: 10.1039/c3sm27940e

We report on the Rayleigh-Plateau instability in films of giant micelle solutions coating a vertical fibre. We observe that the dynamics of thin films coating the fibre could be very different from the Newtonian or standard non-Newtonian cases. By varying the concentration of the components of the solutions and depending on the film thickness, we show for the first time that the Rayleigh-Plateau instability can be stabilized using surfactant solutions. Using global rheology and optical visualisations, we show that the development of shear-induced structures is required to stabilize the micellar film along the fibre. Assuming that the viscoelastic properties of the shear-induced state can be described by a simple model, we suggest that, in addition to the presence of shear-induced structures, the latter must have an elastic modulus greater than a critical value evaluated from a linear stability analysis. Finally, our analysis provides a way of estimating the bulk elasticity of the shear-induced state.