Percolation and viscoelasticity of triblock copolymer micellar solutions

We report analyses of an extensive set of rheological data from triblock copolymer micelles in aqueous solutions. We investigated Pluronic L64 (PEO13PPO30PEO13)–water system in the vicinity of the percolation threshold. The existence of percolation loci has been suggested by previous light (elastic and quasi-elastic) and neutron scattering (small angle-SANS) experiments and their analyses by using a sticky hard sphere model of Baxter. The rheological properties of the system was measured by an oscillating viscometer of the frequency range 0.1–60 (rad/s). From these measurements scaling exponents were determined for frequency-dependent complex moduli. The exponents satisfy the scaling relations predicted by the theory. But their numerical values agree with those from the scalar elasticity percolation theory only at the lowest micellar concentrations.