The synthesis and characterization of a new family of dendritic polymers comprising a hyperbranched polyamidoamine core and polyethyleneglycol-derivative units is reported. The mentioned polymers have either core-shell or core-multishell architectures. Their intrinsic properties (solubility in a wide range of solvents, ability to interact with hydrophilic or hydrophobic compounds, etc.) allows the one-step in situ synthesis of water-soluble ZnO quantum dots via decomposition of an organometallic precursor. The effect of structural properties of the polymer (nature of the shell, core molecular weight, etc.), as well as external stimuli (temperature, ionic strength, etc.) on the formation and/or stabilization of nanoparticles has been evaluated. The as-synthesized nanoparticles could be easily redispersed in various solvents and presented stable photoluminescent properties.

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Branched thermotropic liquid crystals were successfully obtained from ionic interactions between hyperbranched polyamidoamine and sodium dodecylsulfate. These complexes present columnar rectangular and lamellar thermotropic mesophases as demonstrated by polarized optical microscopy, differential scanning calorimetry, and small-angle X-ray scattering. The relationships between the structural characteristics of the polymers (size of the hyperbranched core, hyperbranched or dendritic nature of the core, and substitution ratio) and the mesomorphic properties were studied. In situ formation of gold nanoparticles was then performed. The templating effect of the liquid crystal mesophase resulted in the formation of isotropic nanoparticles, the size of which was dictated by the local organization of the mesophase and by the molar mass of the hyperbranched complex.

Zinc oxide nanoparticles were obtained from the hydrolysis of an organometallic precursor in pure hexadecylamine. Interestingly, we demonstrate that the final (anisotropic or isotropic) shape of the nanoparticles is strongly correlated to the existence of a critical temperature. This suggests that the organization of the fatty amines is a paramount parameter in this synthesis. Moreover, the final hybrid ZnO materials systematically exhibit a liquid-crystal smectic phase, whereas no liquid-crystal phase was observed in the pristine reaction media. This simple process is, therefore, a direct and straightforward method to synthesize liquid-crystal hybrid materials.