More on phase diagram of Laponite

B. Ruzicka; L. Zulian; G. Ruocco

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arXiv · cond-mat/0509235

More on phase diagram of Laponite

B. Ruzicka·L. Zulian·G. Ruocco

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Abstract

The phase diagram of a charged colloidal system (Laponite) has been investigated by dynamic light scattering in a previously unexplored range of salt and clay concentrations. Specifically the clay weight and salt molar concentrations have been varied in the ranges Cw=0.004- 0.025, Cs=(1x 10^-3- 5x 10^-3) M respectively. As in the case of free salt water samples (Cs= 1x 10^-4 M) an aging dynamics towards two different arrested phases is found in the whole examined Cw and Cs range. Moreover a transition between these two different regimes is found for each investigated salt concentration. It is clear from these measurements that a revision of the phase diagram is necessary and a new "transition" line between two different arrested states is drawn.

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B. Ruzicka, L. Zulian, G. Ruocco. 2005-09-09. More on phase diagram of Laponite. https://arxiv.org/abs/cond-mat/0509235

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