Surface patterns in drying films of silica colloidal dispersions

Abstract

We report an experimental study on the drying of silica colloidal dispersions. Here we focus on a surface instability occurring in a drying paste phase before crack formation which affects the final film quality. Observations at macroscopic and microscopic scales reveal the occurrence of the instability, and the morphology of the film surface. Furthermore, we show that the addition of adsorbing polymers on silica particles can be used to suppress the instability under particular conditions of molecular weight and concentration. We relate this suppression to the increase of the paste elastic modulus.

8 pages, accepted in Soft Matter

References in corpus (4)

• Multiple-length-scale elastic instability mimics parametric resonance of nonlinear oscillators
• Unfolding the Sulcus
• Surface sulci in squeezed soft solids
• Structural anisotropy of directionally dried colloids

Cited by in corpus (4)

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• Highly porous layers of silica nano-spheres sintered by drying: Scaling up of the elastic properties from the beads to the macroscopic mechanical properties
• Tessellation-valued processes that are generated by cell division