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arXiv · 1904.02953

Microgels Adsorbed at Liquid-Liquid Interfaces: A Joint Numerical and Experimental Study

Fabrizio Camerin·Miguel Angel Fernandez-Rodriguez·Lorenzo Rovigatti·Maria-Nefeli Antonopoulou·Nicoletta Gnan·Andrea Ninarello·Lucio Isa·Emanuela Zaccarelli
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Abstract

Soft particles display highly versatile properties with respect to hard colloids, even more so at fluid-fluid interfaces. In particular, microgels, consisting of a cross-linked polymer network, are able to deform and flatten upon adsorption at the interface due to the balance between surface tension and internal elasticity. Despite the existence of experimental results, a detailed theoretical understanding of this phenomenon is still lacking due to the absence of appropriate microscopic models. In this work, we propose an advanced modelling of microgels at a flat water/oil interface. The model builds on a realistic description of the internal polymeric architecture and single-particle properties of the microgel and is able to reproduce its experimentally observed shape at the interface. Complementing molecular dynamics simulations with in-situ cryo-electron microscopy experiments and atomic force microscopy imaging after Langmuir-Blodgett deposition, we compare the morphology of the microgels for different values of the cross-linking ratios. Our model allows for a systematic microscopic investigation of soft particles at fluid interfaces, which is essential to develop predictive power for the use of microgels in a broad range of applications, including the stabilization of smart emulsions and the versatile patterning of surfaces.

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Fabrizio Camerin, Miguel Angel Fernandez-Rodriguez, Lorenzo Rovigatti, Maria-Nefeli Antonopoulou, Nicoletta Gnan, Andrea Ninarello, Lucio Isa, Emanuela Zaccarelli. 2019-04-05. Microgels Adsorbed at Liquid-Liquid Interfaces: A Joint Numerical and Experimental Study. https://doi.org/10.1021/acsnano.9b00390

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