Small-angle neutron-scattering study of dense sheared silica gels

Small-angle neutron-scattering (SANS) shearing experiments on dense colloidal silica suspensions in a ${\mathrm{H}}_2$O-${\mathrm{D}}_2$O medium are reported for the wave vector range 0.03Q(${\mathrm{nm}}^{\mathrm{-}1}$)Q corresponding to a contact particle morphology was apparent at all volume fractions. A fractal dimension d=1.60±0.05 was estimated for φ=0.10 and 0.12 by fitting the power law behavior of the structure factor. Shear induces an apparent fractal domain into the dense gels and enhances the contact particle structure.