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Polyacrylamide nanoparticles containing zinc nitrate were prepared via inverse miniemulsion polymerization using ultrasound emulsification. The effects of sonication time, mode of sonication, nature and type of emulsifier, amount of zinc salt, solvent in the dispersed phase, nature of dispersed and continuous phases, and type of initiator on the nucleation mechanism, conversion, molecular mass of polymer, and size distribution of the latex particles were investigated. The results showed that an increase in sonication time up to 4 min and using an amphiphilic polymeric surfactant with a relatively short hydrophilic part improved both the monodispersity and the stability of the zinc-containing latexes. An increase in viscosity of the continuous phase (changed by means of different nonpolar solvents) and decrease in viscosity of the dispersed phase (varied by the amount of water) had also a positive effect on the monodispersity. At the same time, the average diameter of the particles in the range of 225 nm changed only marginally. The use of either highly hydrophilic (ammonium persulfate) or highly hydrophobic (2,2′-azobis(2-methylbutyronitrile)) initiators, and the transfer from miniemulsion polymerization to dispersion, precipitation, or a combination of several polymerization types by the modification of the dispersed and continuous medium spread the polydispersity of the latex particles and impaired the stability. Samples with small content of salt were used for unconventional nanolithography by subjecting a highly ordered layer of the nanoparticles to a plasma etching process. Highly ordered arrays of particles containing ZnO nanocrystals were observed.

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Synthetic polymeric materials are established as being central to many modern approaches to medical treatments such as biomaterial induced tissue regeneration or drug eluting implants. Cytocompatible, antifouling materials, based on hydrophilic polymers such as poly(ethylene glycol), have been widely studied as a 'blank canvas' substrate; it is possible to apply various bioactive ligands to elicit specific tissue and cell responses. In recent years, branched polyglycerols have gained attention as a viable alternative to PEG as a protein-resistance providing chemical moiety. To this end we have embarked on the preparation of bulk polyglycerol-based films, which are readily synthesized from abundant starting materials, with the aim of evaluating their as yet undiscovered potential as macroscopic biomaterials. Herein we report syntheses, as well as mechanical, and rheological properties of a series of polyglycerolbased polymer networks. Polymeric films produced are highly crosslinked, have high thermal stability, and are flexible with thermal glass transition temperatures below body temperature.