Abstract: | Static light scattering and small angle neutron scattering measurements are reported for agarose hydrogels prepared under various conditions of concentration and temperature. For the wide range of transfer wave vector explored, these measurements show that the gels do not display fractal behaviour. Their structure is better described by a stretched exponential form, in which the value of the exponent is n = 0.2. As found by other authors, a maximum in the scattering intensity is observed in the light scattering spectra. The position of the maximum, qmax, depends on the concentration and on the thermal history of the sample. The inverse length 1/qmax is in good agreement with published measurements of the pore size D in this system. Preliminary measurements by small angle scattering indicate that the sol-gel transition is not of spinodal type. |