Wormlike Surfactant Micelles with Embedded Polymer Chains

Abstract

Active use of wormlike micelle (WLM) solutions in a broad range of applications demands control of their viscoelastic properties under different external conditions that can be achieved by using hybrid materials, such as polymer–surfactant complexes. Understanding the properties of such hybrid materials remains a challenge. Using a combination of several experimental techniques with molecular dynamics simulations, we investigate the interaction of poly(4-vinylpyridine) with WLMs of the anionic surfactant potassium oleate. We find that this polymer is solubilized by the micelles at the interface between the tails and headgroups of surfactant, thus screening the hydrophobic polymer backbone from interactions with water while maintaining hydrogen bonding between the pyridine rings and water. By use of SANS with contrast variation, it was shown that the macromolecules associated with the micelles have an expanded coil-like conformation with persistence length 4-fold higher than that of a polymer chain in a go...