Calcium Carbonate Core Research Articles

Small angle neutron scattering studies on non-aqueous dispersions of calcium carbonate

Colloidal dispersions of calcium carbonate in toluene, with the particles stabilised by an alkyl aryl sulphonic acid, have been examined by small angle neutron scattering. On the basis of the assumption that the adsorbed layer of stabilising surface active agent formed a concentric shell around a spherical calcium carbonate core particle, a method was developed to determine both the radius of the core particle and the thickness of the adsorbed layer. For the two series of particles examined the calcium carbonate core particles were found to have radii of 22 and 67 a respectively and in both cases the adsorbed layer thickness was found to be 19.0±1 a. The method provides a means of obtaining adsorbed layer thicknesses under conditions where particle and layer cannot be separated.