Local Dielectric Spectroscopy of Nanocomposite Materials Interfaces

TL;DR

This study uses local dielectric spectroscopy via electrostatic force microscopy to analyze how inorganic nano-inclusions affect the relaxation dynamics and dielectric properties of ultra-thin polymer films at nanometer resolution.

Contribution

It introduces a method to spatially resolve dielectric property variations at the nanoscale in polymer nanocomposites using electrostatic force microscopy.

Findings

Spectral changes occur at the polymer-inclusion boundary.

Dielectric loss spectra vary across nanostructures.

Spatial dielectric variations are visualized at nanometer resolution.

Abstract

Local dielectric spectroscopy is performed to study how relaxation dynamics of a poly-vinyl-acetate ultra-thin film is influenced by inorganic nano-inclusions of a layered silicate (montmorillonite). Dielectric loss spectra are measured by electrostatic force microscopy in the frequency-modulation mode in ambient air. Spectral changes in both shape and relaxation time are evidenced across the boundary between pure polymer and montmorillonite sheets. Dielectric loss imaging is also performed, evidencing spatial variations of dielectric properties near to nanostructures with nanometer scale resolution.