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Phase Behavior in Thin Films of Confined Colloid-Polymer Mixtures

Chun-lai Ren·Yu-qiang Ma
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Abstract

Using self-consistent field and density-functional theories, we first investigate colloidal self-assembling of colloid/polymer films confined between two soft surfaces grafted by polymers. With the increase of colloidal concentrations, the film undergoes a series of transitions from disordered liquid $\to$ sparse square $\to$ hexagonal (or mixed square-hexagonal) $\to$ dense square $\to$ cylindric structures in plane, which results from the competition between the entropic elasticity of polymer brushes and the steric packing effect of colloidal particles. A phase diagram displays the stable regions of different in-layer ordering structures as the colloidal concentration is varied and layering transitions as the polymer-grafted density is decreased. Our results show a new control mechanism to stabilize the ordering of structures within the films.

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Chun-lai Ren, Yu-qiang Ma. 2006-10-21. Phase Behavior in Thin Films of Confined Colloid-Polymer Mixtures. https://arxiv.org/abs/cond-mat/0610591

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