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

Soft particles display highly versatile properties with respect to hard colloids, even more so at fluid-fluid interfaces. In particular, microgels, consisting of a crosslinked 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 network and is able to reproduce the experimentally observed shape of the microgel 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 crosslinking 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.