Three-Phase Coexistence in Colloidal Rod-Plate Mixtures.

نویسندگان

  • Phillip Woolston
  • Jeroen S van Duijneveldt
چکیده

Aqueous suspensions of clay particles, such as montmorillonite (MMT) platelets and sepiolite (Sep) rods, tend to form gels at concentrations around 1 vol %. For Sep rods, adsorbing sodium polyacrylate to the surface allows for an isotropic-nematic phase separation to be seen instead. Here, MMT is added to such Sep suspensions, resulting in a complex phase behavior. Across a range of clay concentrations, separation into three phases is observed: a lower, nematic phase dominated by Sep rods, a MMT-rich middle layer, which is weakly birefringent and probably a gel, and a dilute top phase. Analysis of phase volumes suggests that the middle layer may contain as much as 6 vol % MMT.

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عنوان ژورنال:
  • Langmuir : the ACS journal of surfaces and colloids

دوره 31 34  شماره 

صفحات  -

تاریخ انتشار 2015