Development of a novel polymer-metal nanocomposite obtained through the route of in situ reduction and its dielectric properties [capacitor applications]

Composites of metal particles within a dielectric medium have attracted a lot of attention because of the interesting properties exhibited by them. For integral capacitors, the polymer composite material has emerged as a potential candidate, since it meets the requirements of low processing temperature and reasonably high dielectric constant. Rao Yang and C.P. Wong (US Patent filed 4/29/2001) have demonstrated novel integral passive component materials with tremendously high dielectric constant (k>1,000) and high reliability performance. These materials have high dielectric constant, based on the interfacial polarization mechanism, but they need precision filler concentration control. The current study overcomes this drawback and achieves the composite through an in-situ reduction of silver in an epoxy matrix. Various parameters affecting the nanoparticle size are discussed and optimum conditions obtained. Material characterization was done through TEM, SEM, EDAX and X-ray analysis. Dielectric characterization is done through an LCR meter. Novel dielectric behavior has been observed and possible Coulombic blockade effects are discussed to explain the novel behavior.