Organic–inorganic hybrid hollow spheres are prepared by using a TiO2‐stabilized Pickering emulsion polymerization method (see figure). By self‐organization of TiO2 nanoparticles at the interface of oil (monomer and solvent) and water, colloidosomes are formed and used as polymerization vessels to obtain the hybrid hollow spheres. The diameter and mechanical stability can be tailored by varying the relative amount of oil phase and the relative amount of divinylbenzene (DVB) in the monomer, respectively.

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Solid-stabilized, or Pickering, miniemulsion polymerizations using Laponite clay discs as stabilizer are investigated. Free radical polymerizations are carried out using a variety of hydrophobic monomers (i.e., styrene, lauryl (meth)acrylate, butyl (meth)acrylate, octyl acrylate, and 2-ethyl hexyl acrylate). Armored latexes, of which the surfaces of the particles are covered with clay discs, are obtained, as confirmed by scanning electron microscopy (FE-SEM) and atomic force microscopy (AFM). Overall polymerization kinetics of the Pickering miniemulsion polymerizations of styrene were investigated via gravimetry. Comparison with the bulk polymerization analogue clearly shows compartmentalization. Moreover, retardation effects up to intermediate monomer conversions are observed; they are more prominent for the smaller particles and are ascribed to the Laponite clay. A model is presented that allows for the prediction of the average particle size of the latexes produced as a function of the amounts of monomer and Pickering stabilizers used. It shows that under specific generic conditions the number of clay discs used correlates in a linear fashion with the total surface area of the latex particles. This is a direct result of the reversibility of the Laponite clay disc adhesion process under the emulsification conditions (i.e., sonication) used.