Model poly(glycerol monomethacrylate)-based macromonomers have been used to prepare sterically stabilized polystyrene latexes by either aqueous emulsion or alcoholic dispersion polymerization, affording mean latex diameters of approximately 107 or 1188 nm respectively as judged by dynamic light scattering. Such PGMA50−PS latexes have appropriate surface wettability to stabilize 25−250 μm oil-in-water Pickering emulsions, depending on the latex concentration and oil type. Colloidosomes were formed by covalent cross-linking of the hydroxyl-functional stabilizer chains from within the oil droplets using a polymeric diisocyanate (tolylene 2,4-diisocyanate-terminated poly(propylene glycol) [PPG-TDI]. This oil-soluble cross-linker was confined within the oil droplets, allowing colloidosomes to be prepared at 50 vol % solids without any aggregation. The resulting microcapsules survive removal of the internal oil phase using excess alcohol, unlike the noncross-linked Pickering emulsion precursor. These observations confirm the robust nature of these covalently stabilized colloidosomes. A method for controlling the permeability of these colloidosomes by exploiting the solvent properties of binary oil mixtures has also been evaluated. Finally, microcapsule permeability has been explored via dye release experiments. Less permeable microcapsules can be obtained by deposition of polypyrrole onto the colloidosome exterior.

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Phthalonitrile polymers with amide and ortho-, meta-, and para-substituted ether linkages in the backbone were synthesized successfully and their thermal properties were investigated. The monomer building blocks for these polymers were cured without the addition of catalysts due to the self-catalyzing nature of the monomer's amino group. The ether and amide functionalities in the chain enhanced their processability without compromising thermal stability. The resins exhibited a low complex viscosity over a wide processing window between the monomer melting temperature and the polymer cure temperature, with the processing temperature range varying significantly for para-, ortho-, and meta-substituted polymer architectures. All three systems exhibited high thermal and thermo-oxidative stability. The high char yields, which ranged from 66-75% at 900 °C under nitrogen atmosphere, and the high glass transition temperatures of the polymers indicate a high crosslinking density in the network structure.

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