Synthesis of monodispersed polystyrene-silver core-shell particles and their application in the fabrication of stretchable large-scale anisotropic conductive films

Monodispersed core-shell conductive particles are designed and produced as efficient electron transporting materials for anisotropic conductive films. Traditionally, particle size control was required usually owing to the demand of anisotropic conductive films. Here, an innovative and facile method is proposed to prepare large-scale anisotropic conductive films by incorporating organic-inorganic core-shell conductive particles. First of all, monodispersed polystyrene-silver (PS-Ag) core-shell particles were prepared by emulsifier-free emulsion polymerization and a modified electroless plating process. A series of variables were used to synthesize the PS-Ag conductive particles to enhance the mobility of electrons in a given medium. The resulting PS-Ag conductive particles had excellent bulk conductivity with Ag nanoshells compactly embedded on the surface of PS colloids. In addition, the PS-Ag conductive particles were further mixed with soft latex particles of poly(styrene-co-butyl acrylate), P(St-BA), and then followed by the film-forming process. After the formation of large-scale anisotropic conductive films by the gravity sedimentation method, a remarkable flexible behavior with good conductivity was obtained. The presented method shows the significance of developments in electronic fields and is expected to be a practical, facile, and general approach for the fabrication of anisotropic conductive films with good flexibility and stretchability.