Polymer grafted silver and copper nanoparticles with exceptional stability against aggregation by a high yield one-pot synthesis

A straightforward synthesis of silver nanoparticles (mean diameters well below 4 nm) with a graft-to polystyrene shell (PS@Ag) is described and different synthesis routes are compared. In addition to standard methods like TEM, XRD, UV/Vis and DSC the hybrid material has also been characterized by gel permeation chromatography (GPC). Long-term stable hybrid materials with silver contents up to 18 wt-% have been realized. The exceptional stability allows industrial-scale processing by melt extrusion. No aggregation or agglomeration of silver nanoparticles is observed after melt co-extrusion with conventional polystyrene at 190 C. The co-extruded blends with silver nanoparticle contents up to 1 wt-% show a homogenous dispersion of nanoparticles in the polystyrene matrix. The synthesis route has also been applied to PS-block-PMMA stabilized silver nanoparticles and to copper to yield polystyrene-stabilized copper nanoparticles with diameters well below 3 nm. (C) 2011 Elsevier Ltd. All rights reserved.