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Nanoemulsions of water, Brij 56 and hexyl methacrylate (with a small amount of squalene as hydrophobe or costabilizer) were made by the phase inversion temperature (PIT) method and then polymerized. In the absence of squalene, the nanoemulsions destabilized within minutes; however with squalene, the nanoemulsions were kinetically stable for at least several hours, which is long enough to carry out the reactions, with diameters of narrow size distribution in the range from 32 to 44 nm, depending on the surfactant concentration. Polymerizations, carried out a 20°C using a par redox, were extremely fast (ca. 100% conversion in less than 5 min) yielding polymer particles of ca. 40 nm, which were similar to the original nanoemulsion droplets (ca. 35 nm), indicating that the nanoemulsion droplets act as templates, and that squalene diminishes substantially monomer diffusion between reacting and nonreacting monomer droplets. Molar masses were high and alike to those produced by microemulsion polymerization of this monomer, suggesting that chain transfer to monomer is the main termination mechanism.

The synthesis of poly(hexyl methacrylate) nanoparticles in nanoemulsions containing squalane as hydrophobe is reported here. A comparison of the polymerization kinetics of nanoemulsions prepared by Phase Inversion Temperature (low energy method) and microfluidization (high energy method), as well as polymer characteristics are presented. Nanoemulsion polymerizations carried out a 20°C were extremely fast using a par redox especially for the low-energy nanoemulsions. The particles obtained were only slightly larger than the original nanoemulsion droplets, indicating that the droplets acted as templates, and that squalane diminished substantially monomer diffusion between reacting and non-reacting monomer droplets. Molar masses and glass transition temperatures of the poly(hexyl methacrylate) obtained here were practically independent of conversion and surfactant concentration, as well as of the nanoemulsification method used.

New oil-in-alcohol highly concentrated emulsions were formulated and were used as a templates to obtain macroporous poly(furfuryl alcohol) monoliths by a one-step method. The oil-in-alcohol highly concentrated emulsions were prepared by stepwise addition of the oil phase to the surfactant-alcohol solution and were characterized by optical microscopy and by laser diffraction. The typical structure of highly concentrated emulsions, with close-packed polyhedral droplets, has been observed. Poly(furfuryl alcohol) monoliths were obtained by polymerizing in the external phase of these emulsions. These materials are mainly macroporous and retain the size distribution and morphology from the highly concentrated emulsions. The internal structure of the monoliths was observed by scanning electron microscopy. The images showed an interconnected network with pore size similar to the droplet size of the highly concentrated emulsions used as templates.

A simple method for the preparation of carbonaceous materials, by pyrolization of poly(vinylidene chloride) macroporous foams is described, by polymerizing in the external phase of highly concentrated emulsions. These emulsions are characterized by a volume fraction of the disperse phase larger than 0.74, the maximum volume fraction for the most compact arrangement of uniform spherical droplets. The polymerized macroporous foams have an interconnected pore network with very high total pore volume, which replicated the original emulsion that was used as a template. After pyrolization, carbonaceous porous materials can be obtained, with high pore volume and large specific surface area. These materials could be used for pollutant removal to energy storage.

Highly concentrated emulsions (dispersed phase volume fraction exceeding 0.74) also known as high-internal-ratio-emulsions (HIPREs) or gel emulsions are interesting as templates for advanced materials. By polymerization of the continuous phase, materials with dual meso/macroporous structure have been obtained. Control of the pore size and morphology of the material is achieved by controlling the size and size distribution of the emulsion droplets and the nanostructure of the continuous phase. The objective of this work was to obtain carbonaceous materials with a high pore volume by a simple method. To fulfill this aim, 1,1-dichloroethene was used as oil phase and a block copolymer as surfactant as emulsifier. The carbonaceous material was obtained by polymerization of 1,1-dichloroethene in the external phase of the highly concentrated W/O emulsion followed by pyrolyzation. The resulting materials have been characterized by electron microscopy and N sorption isotherms. The results have shown that the carbonaceous materials possess a high pore volume and a complex porous texture.