Gelation of Micellar Block Polyelectrolytes: Evidence of Glassy Behavior in an Attractive System

Abstract

We present small-angle neutron scattering and rheology for micellar solutions of polystyrene−poly(acrylic acid) block copolymers that can be regarded as attractive colloids. These systems form gels at high effective micellar volume fractions (φ > 0.64) that are suggestive of disordered colloidal glasses. At the gel point, the solution rheology follows the scaling predicted by classical percolation theory, with G‘ ∼ G‘‘ ∼ ωΔ. We argue that this scaling could be due either to formation of a percolated network or to a pretransitional glassy phase.