Eur. Phys. J. E 27, 261-273 (2008)
DOI: 10.1140/epje/i2008-10379-2

On the concentration-induced growth of nonionic wormlike micelles

S. Bulut¹, J. Hamit¹, U. Olsson¹ and T. Kato<sup>2

1</sup>  Physical Chemistry 1, Center for Chemistry and Chemical Engineering, Lund University, P.O.Box 124, SE-22100, Lund, Sweden
²  Department of Chemistry, Tokyo Metropolitan University, 1-1 Minamiohsawa, Hachioji, 192-0397, Tokyo, Japan

Sanja.Bulut@fkem1.lu.se

Received 18 March 2008 / Revised version 9 September 2008 / Published online 30 October 2008

Abstract

We present a comprehensive study of the concentration-induced growth of nonionic wormlike micelles in dilute solutions, below the overlap concentration, where we combine static and dynamic light scattering and NMR self-diffusion. The data are analyzed in detail in terms of the number-averaged contour length, assuming an exponential size distribution, as predicted by theory, and that the micellar flexibility can be described by the wormlike chain model with a certain persistence length. A very good agreement between the different experimental methods is obtained. The number-averaged contour length increases with increasing micelle volume fraction. The data are consistent with a power law, where the power law exponent is in the range 0.5-0.8, depending on the system. The result is in reasonable agreement with the theory of living polymers.

PACS
64.75.Yz - Self-assembly.
82.70.Uv - Surfactants, micellar solutions, vesicles, lamellae, amphiphilic systems, (hydrophilic and hydrophobic interactions).
82.56.Lz - Diffusion.

Correspondence: Sanja.Bulut@fkem1.lu.se


© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2008