The Effect of Aggregation in Aqueous Aerosil Dispersions on Their Structure and Mechanical Properties

The dynamics of the structure disintegration in the A-175 aerosil dispersions in water and sodium dodecylbenzenesulfonate (SDBS) aqueous solutions was studied by the rotational viscometry. The aqueous dispersions of aerosil were found to be characterized by a high degree of aggregation. At the volume content of the dispersed phase ϕ = 0.063–0.082, the flow of the dispersions is described in terms of the theory of highly aggregated systems. The effect of SDBS on the flow behavior of aerosil dispersions is complex. There is a range of SDBS concentrations (C = 2.87 × 10–6–1.44 × 10–5 mol/l) where it has a noticeable structuring effect. Aerosil dispersions in micellar SDBS solutions (C > 3.0 × 10–3 mol/l) demonstrated the behavior of slightly structured systems characterized by the quasi-Newtonian flow.