Space charge analysis of epoxy boron nanocomposites and the importance of dispersion techniques

The present research work analyzes the space charge
(S.C.) behavior and correlated dynamics in epoxy based nano-
composites (NC) with hexagonal boron nitride (hBN) nano- particles.
The importance of adopting an effective particle dispersion technique
for producing such nano-composites is also experimentally validated.
Three different dispersion techniques are contrasted in terms of the
corresponding space charge behavior exhibited, and the interplay
between increasing filler content and dispersion techniques is
investigated and reported. It is observed that an effective particle
dispersion technique results in a homogeneous distribution of nano-
particles in the polymeric matrix, which in turn gives rise to evenly
distributed trap sites and affects the local mobility of charge carriers,
effectively restraining them. More significantly, since most of the
developed trap-sites are located close to/in the interfacial zone
between the injecting electrode and nano-composite specimen, an
initial, reasonably homogeneous distribution of nano-particles at
relatively lower loading (vol. %) is just as efficient in restricting bulk
space charge accumulation as higher loaded nano-composite
specimens – proving the importance of adopting an effective particle
dispersion technique. Achieving lower levels of bulk space charge
accumulation (as demonstrated in this work) results in smaller
internal electric field distortion and stress in insulation material, thus
having the beneficial effect of prolonging operational life-time and
increased reliability.