Faculté des sciences

Cluster, glass, and gel formation and viscoelastic phase separation in aqueous clay suspensions

Shalkevich, Andrey ; Stradner, Anna ; Bhat, Suresh Kumar ; Muller, François ; Schurtenberger, Peter

In: Langmuir, 2007, vol. 23, no. 7, p. 3570 -3580

We have systematically investigated the phase diagram of clay particles in water to understand the relation between the local and macroscopic properties and the structures of clay suspensions. We focused, in particular, on sodium Cloisite (CNa) particles at concentrations typically used in nanocomposites (concentrations from 1 to 4 wt %) and at an extended range of ionic strengths (10⁻⁵ to... Plus

Ajouter à la liste personnelle
    Summary
    We have systematically investigated the phase diagram of clay particles in water to understand the relation between the local and macroscopic properties and the structures of clay suspensions. We focused, in particular, on sodium Cloisite (CNa) particles at concentrations typically used in nanocomposites (concentrations from 1 to 4 wt %) and at an extended range of ionic strengths (10⁻⁵ to 10⁻² M NaCl). The suspensions have been characterized using rheology and a combination of scattering techniques (neutrons, X-rays, and light). We demonstrate the existence of a liquid cluster phase at low clay and intermediate salt concentrations and provide new insight into the nature of the solidlike dispersions at low and high ionic strengths.