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arXiv · 2408.11320

Novel stabilization mechanisms for concentrated emulsions with tunable morphology via amphiphilic polymer-grafted nanoparticles

Kojiro Suzuki·Yusei Kobayashi·Takashi Yamazaki·Toshikazu Tsuji·Noriyoshi Arai
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Abstract

This study explores the stabilization mechanisms of concentrated emulsions with tunable morphology using amphiphilic polymer-grafted nanoparticles (PGNPs). We employ coarse-grained molecular simulations to investigate concentrated oil-in-water emulsions stabilized by partially hydrolyzed poly(vinyl alcohol)-grafted poly(methyl methacrylate) (PMMA) particles. Two grafting architectures were examined: hydrophilic-hydrophobic (AB-type) diblock PGNPs and reverse BA-type diblock PGNPs. Our findings reveal that AB-type diblock PGNPs tend to aggregate, leading to droplet-droplet coalescence. In contrast, BA-type diblock PGNPs disperse effectively in the water phase, stabilizing robust emulsion through a space-filling mechanism. The study further demonstrates that the stability and morphology of the emulsions can be tuned by varying the number of PGNPs. Our results suggest that BA-type diblock PGNPs are more effective in stabilizing concentrated emulsions, offering insights for the design of novel emulsifiers in industrial applications.

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Kojiro Suzuki, Yusei Kobayashi, Takashi Yamazaki, Toshikazu Tsuji, Noriyoshi Arai. 2024-08-21. Novel stabilization mechanisms for concentrated emulsions with tunable morphology via amphiphilic polymer-grafted nanoparticles. https://arxiv.org/abs/2408.11320

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