Aggregation Patterns of Salt Crystalizing in Drying Colloidal Solvents

TL;DR

This study investigates how salt crystals form intricate fractal and dendritic patterns within drying colloidal gel droplets, influenced by the gel material and substrate, revealing complex segregation phenomena.

Contribution

It provides detailed observations of salt crystallization patterns in different colloidal gels and substrates, highlighting the influence of material properties on pattern formation.

Findings

Salt crystallizes in fractal and multi-fractal dendritic forms.

Pattern morphology depends on gel type and substrate.

Distinct structures observed across potato starch, gelatine, and CMC gels.

Abstract

We report a study of the structure of droplets of colloidal gels containing dissolved sodium chloride. The components segregate and form intricate patterns. The salt crystalizes in fractal and multi-fractal dendritic forms which are determined by the material which forms the colloidal gel. Here potato starch, gelatine and carboxymethyl cellulose have been used. The substrate also plays a role in some cases. Photographs and micrographs at different level of magnification are shown.