Impact of Particles Surface Functionalization on Interphase Properties of PI/Si3N4 Nanocomposites Using AFM

Abstract

In the electrical insulation field, polymer nanocomposites (NC) organic/inorganic hybrid materials assure a distinct improvement of their macroscopic dielectric properties. These improvements are related to the nanoparticle/matrix interphase, a region where the presence of the nanoparticle changes the matrix properties. Moreover, recent studies show that a surface functionalization allows a better dispersion of the particles within the host matrix. This better dispersion plays a major role in the nanocomposite improvement properties. The aim of this work is to present the effect of the surface functionalization of spherical silicon nitride (Si <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> N <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> ) nanoparticles on the interphase regions within a polyimide (PI) matrix. For this reason, mechanical (Young modulus) and electrical (permittivity) interphase nanoscale properties are measured using the quantitative nano mechanical (PF QNM) and the electric force microscopy (EFM) modes of the atomic force microscopy (AFM). These mechanical and electrical quantitative results allow us to compare the interphase dimension and properties between treated and untreated Si <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> N <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> nanoparticles in order to correlate them to macroscopic properties modification.