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arXiv · 2006.02065

Phase stability of dispersions of hollow silica nanocubes mediated by non-adsorbing polymers

Frans Dekker·Alvaro Gonzalez Garcia·Albert P. Philipse·Remco Tuinier
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Abstract

Although there are theoretical predictions [\textit{Eur.~Phys.~J.~E} \textbf{41} (2018) 110] for the rich phase behaviour of colloidal cubes mixed with non-adsorbing polymers, a thorough verification of this phase behaviour is still underway; experimental studies on mixtures of cubes and non-adsorbing polymers in bulk are scarce. In this paper, mixtures of hollow silica nanocubes and linear polystyrene in \textit{N,-N-}dimethylformamide are used to measure the structure factor of the colloidal cubes as a function of non-adsorbing polymer concentration. Together with visual observations these structure factors enabled us to assess the depletion-mediated phase stability of cube-polymer mixtures. The theoretical and experimental phase boundaries for cube-depletant mixtures are in remarkable agreement, despite the simplifications underlying the theory employed.

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Frans Dekker, Alvaro Gonzalez Garcia, Albert P. Philipse, Remco Tuinier. 2020-06-03. Phase stability of dispersions of hollow silica nanocubes mediated by non-adsorbing polymers. https://arxiv.org/abs/2006.02065

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