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The cationic polymerization of p-methoxystyrene (pMOS) in miniemulsion in the presence of dodecylbenzenesulfonic acid (DBSA) was studied. DBSA acts as both protonic initiator and surfactant (INISURF). The recipe was first optimized to generate stable latexes from a miniemulsion, i.e., droplets/ particles of constant size throughout the polymerization. The miniemulsion polymerization process was highly reproducible, quite fast at high temperatures (100% conversion in 8 h at 60 °C) and applicable even at high monomer content (typically 40 wt %). Poly(pMOS) of small average molar masses (≈1000 g mol -1 ) and controlled functionality were synthesized. The sharp increase in molar masses at low conversion was indebted to a decrease of water content at the interface through a cosurfactant effect. Above 20% conversion, the chain length limitation, also observed in previous ionic polymerizations in emulsion studies and referred to as critical DP, was confirmed by modeling simple kinetics. At final conversion, polymer degradation occurred as revealed by SEC, MALDI-TOF, and 1 H NMR. The particles quickly coalesced in the absence of a cosurfactant.

Supracolloidal interpenetrating polymer network reinforced capsules are prepared by using micron-sized colloidosomes of poly(methyl methacrylate-co-divinylbenzene) microgels as reaction vessels. An interpenetrating polymer network as scaffold is generated via radical polymerisation of the interior phase to produce hollow supracolloidal structures with a raspberry core-shell morphology. Their flexibility is tailored by variation of the monomer feed composition.Solid particles can undergo directed self-assembly onto liquid/ liquid or liquid/gas interfaces. This enhances the stability of the interface and is often referred to as Pickering stabilisation. 1,2 Hildebrand et al. 3 suggested that the reason for stabilisation is that the particles are partially wettable by the two phases involved. Moreover, they postulated that when solid powders are used to stabilise emulsions, the type of emulsion produced is determined by the angle of contact of the interface with the solid. ''In order for the powder to remain in the interface the angle must be finite, and unless the angle is 90u, the interface will be on one side or the other of the points of contact of the particles, and its tension will cause the film to be concave on that side.'' Pieranski demonstrated, by solely taking into account interfacial tensions, that the solid particles are in essence trapped in a surface energy well, with an escape barrier to re-enter either one of the bulk phases of several orders of magnitude larger than the thermal energy, k B T. 4 Recently, Pickering stabilisation has been used advantageously to create supracolloidal structures using particles as building blocks. Velev et al. described the synthesis of hollow structures via assembly of polystyrene latex on the interface of