Structure and dielectric properties of composite material based on surface-modified BaTiO₃ nanoparticles in polystyrene

Department of Physics and Nanotechnology, Kursk State University, 33, Radishcheva Str., Kursk 305000, Russia

^a e-mail: nikita_emelyanov@bk.ru

Received: 26 August 2014
Revised: 24 November 2014
Accepted: 28 November 2014
Published online: 7 January 2015

Abstract

This article reports on studies of the structure and dielectric properties of composites materials based on BaTiO₃ nanoparticles in the polymer matrix. It is shown that nanoparticles of barium titanate obtained by peroxide method, have surface enriched hydroxyl (-OH) groups, which allow the formation of strong chemical bonds with the molecules of surfactant. This surface modification prevents agglomeration of nanoparticles, which leads to heterogeneity of mechanical and dielectric properties of the composites. It is shown that the effective dielectric constant for the studied composite material agrees well with the modified Kerner equation for the volume content of nanoparticles within the range from 5 to 35%.