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Effect of Particle Interactions on the Assembly of Drying Colloidal Mixtures.

ABSTRACT: The effects of particle interactions on the size segregation and assembly of colloidal mixtures during drying were investigated. A cationic surfactant was added to a binary latex/silica colloidal dispersion that has been shown to self-stratify upon drying at room temperature. Atomic force microscopy was used to show that the change in particle interactions due to the presence of surfactants reduced the degree of stratification and, in some cases, suppressed the effect altogether. Colloidal dispersions containing higher surfactant concentrations can undergo a complete morphology change, resulting instead in the formation of armored particles consisting of latex particles coated with smaller silica nanoparticles. To further prove that armored particles are produced and that stratification is suppressed, cross-sectional images were produced with energy-dispersive X-ray spectroscopy and confocal fluorescence microscopy. The growth of armored particles was also measured using dynamic light scattering. To complement this research, Brownian dynamics simulations were used to model the drying. By tuning the particle interactions to make them more attractive, the simulations showed the presence of armored particles, and the size segregation process was hindered. The prevention of segregation also results in enhanced transparency of the colloidal films. Overall, this research proves that there is a link between particle interactions and size segregation in drying colloidal blends and provides a valuable tool to control the assembly of different film architectures using an extremely simple method.

SUBMITTER: Tinkler JD

PROVIDER: S-EPMC9097527 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature

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Effect of Particle Interactions on the Assembly of Drying Colloidal Mixtures.

Tinkler James D JD Scacchi Alberto A Argaiz Maialen M Tomovska Radmila R Archer Andrew J AJ Willcock Helen H Martín-Fabiani Ignacio I

Langmuir : the ACS journal of surfaces and colloids 20220419 18

The effects of particle interactions on the size segregation and assembly of colloidal mixtures during drying were investigated. A cationic surfactant was added to a binary latex/silica colloidal dispersion that has been shown to self-stratify upon drying at room temperature. Atomic force microscopy was used to show that the change in particle interactions due to the presence of surfactants reduced the degree of stratification and, in some cases, suppressed the effect altogether. Colloidal dispe ...[more]

PMID: 35439018

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Dataset Information

Effect of Particle Interactions on the Assembly of Drying Colloidal Mixtures.

Publications

Effect of Particle Interactions on the Assembly of Drying Colloidal Mixtures.

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