Authors: A. Voronov, A. Kohut and W. Peukert
Affilation: Friedrich-Alexander University Erlangen-Nuremberg, Germany
Pages: 17 - 19
Keywords: smart silver nanoparticles, invertible polyesters, nanoreactors
A simple way to prepare uniform amphiphilic silver nanoparticles in concentrated solutions of an invertible polyester is developed. The mobility of polymer fragments increases by dissolving of the polyester in benzene. Experimental data show that microphase separation of polyester units resulting in subsequent large range ordering occurs. Incompatible hydrophilic and hydrophobic constituents of the polyester form micellar domains that are used for the synthesis of nanoparticles. The shape and size of the domains depend on the polyester concentration and the ratio between the lipophilic and hydrophilic constituents in the macromolecule as well as on solvent (reaction medium) polarity. The silver complex is trapped in the polymeric nanoreactors and is reduced by their hydrophilic poly(ethylene glycol) branches. Due to the invertible properties of the polyester, the developed silver nanocolloids are amphiphilic and form stable colloidal solutions in both polar and nonpolar dispersion media. Controlled packing of nanoparticles is achieved by self-organization of the stabilized clusters on casting from a solution. The described technique can be extended for the preparation of a variety of metal nanoparticles (for example, gold) under appropriate conditions.