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Layer-by-layer assembly of colloidal particles deposited onto the polymer-grafted elastic substrate

Kang Chen·Yu-qiang Ma
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Abstract

We demonstrate a novel route of spatially organizing the colloid arrangements on the polymer-grafted substrate by use of self-consistent field and density functional theories. We find that grafting of polymers onto a substrate can effectively control spatial dispersions of deposited colloids as a result of the balance between colloidal settling force and entropically elastic force of brushes, and colloids can form unexpected ordered structures on a grafting substrate. The depositing process of colloidal particles onto the elastic "soft" substrate includes two steps: brush-mediated one-dimensional arrangement of colloidal crystals and controlled layer-by-layer growth driven entropically by non-adsorbing polymer solvent with increasing the particles. The result indicates a possibility for the production of highly ordered and defect-free structures by simply using the grafted substrate instead of periodically patterned templates, under appropriate selection of colloidal size, effective depositing potential, and brush coverage density.

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Kang Chen, Yu-qiang Ma. 2006-11-04. Layer-by-layer assembly of colloidal particles deposited onto the polymer-grafted elastic substrate. https://arxiv.org/abs/cond-mat/0611105

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