Gels formed from very polydispersive gelatin solutions were studied by intensity fluctuation spectroscopy. Single exponential autocorrelation functions were obtained for gelatin gels with and without a crosslinking agent. The elastic continuum model was found to adequately describe all the observed properties. As the concentration increases the cooperative diffusion coefficientDcof the polymer network decreases in the solution state, but increases in the gel state. For gels without a crosslinking agent, the decay rate of the correlation function was found to remain constant after it reached a terminal value several hours after its temperature was lowered to 20thinsp;deg;C. However, for gels with a crosslinking agent, the decay rate continuously increased and the spatial correlation length became shorter with time.
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