Microgel-Based Adaptive Hybrid Capsules with Tunable Shell Permeability

In the present work, we demonstrate the preparation of adaptive hybrid capsules with microgel/SiO 2 composite walls. During the first stage of the capsule synthesis process, microgel particles stabilize the oil droplets in water and become self-assembled on the oil/water interface. At the second stage, microgels are subsequently glued by the sol–gel reaction of a silica precursor-hyperbranched polyethoxysiloxane (PEOS) which occurs at the oil/water interface. Consequently, hybrid capsules consisting of silica shell with embedded microgels are obtained. Responsive microgels present in the capsule wall act as transportation channels for different encapsulated materials. The use of smart microgels allows us to design capsules with controlled size, morphology, and wall permeability able to operate in both water and organic solvents.