Percolation and viscoelasticity of triblock copolymer micellar solutions

We report analyses of an extensive set of rheological data from triblock co polymer micelles in aqueous solutions. We investigated Plutonic L64 (PEO13P PO30PEO13)-water system in the vicinity of the percolation threshold. The e xistence of percolation loci has been suggested by previous light (elastic and quasi-elastic) and neutron scattering (small angle-SANS) experiments an d their analyses by using a sticky hard sphere model of Baxter. The rheolog ical properties of the system was measured by an oscillating viscometer of the frequency range 0.1-60 (rad/s). From these measurements scaling exponen ts were determined for frequency-dependent complex moduli. The exponents sa tisfy the scaling relations predicted by the theory. But their numerical va lues agree with those from the scalar elasticity percolation theory only at the lowest micellar concentrations. (C) 1999 Published by Elsevier Science B.V, All rights reserved.