Critical behavior of gelation probed by the dynamics of latex spheres

We report a quasielastic light scattering study of the dynamics of large latex probe particles (R=225 nm) in gelatin solution undergoing gelation. We show that by focusing on the short-time and long-time behavior of the autocorrelation function, it is possible to simply interpret out data in terms of the divergence of the viscosity and emergence of the shear elastic modulus near the gel point. Our crude analysis allows us to grasp the critical behavior of gelation and to obtain the two critical exponents of the transport properties.