We have observed, for the first time, the major change in resistance which results from the collapse of the interconnected gel network at the gelndash;sol transition. The dc resistivity and ac resistivity (le;10 kHz) were measured as functions of temperature and concentration. At the gelndash;sol transition, the resistivity increases sharply; in some cases by almost two orders of magnitude. Quantitative analysis of the transport data for detailed comparison with the onset of shear modulus (exponents, etc.) is complicated by the simultaneous occurrence of the rodndash;coil transition and by a background ionic contribution which leads to finite conductance at concentrations below the critical concentration.
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