Vovchenko L.L.


The influence of structure and morphology of nanocarbon component on thermal and electrical properties of carbon composites
01.04.07 – solid state physics
Doctor of Science Degree (Physics and Mathematics)

The thesis is devoted to study of structure, thermal and electrical properties of carbon-polymer composites and the parameters of the interaction with electromagnetic radiation (EMR) of microwave range (25.5-37.5 GHz). Three-dimensional (3-D) Monte Carlo simulation has been performed for predicting the percolation threshold in electrical conductivity of polymer composites filled with conductive particles of various morphologies – graphite nanoplatelets, carbon nanotubes, thermoexfoliated graphite (TEG). The model of effective electrical conductivity and extended mixture model for thermal conductivity have been developed for carbon-polymer composites. These models take into account the morphology of the carbon filler, its own electrical (thermal) conductivity, the spatial orientation of the carbon particles in composite and the electrical (thermal) contact resistance between them in formed continuous fillers chains. The electrical conductivity, complex dielectric permittivity, EMR reflection and absorption indexes have been defined for the pressed samples of TEG, TEG-metal (Co, Ni, Cu) and epoxy composites with carbon fillers of different structure and morphology. The effect of filler distribution in epoxy matrix on the efficiency of interaction with EMR has been established.
Key words: graphite nanoplatelets, carbon nanotubes, carbon-polymer composites, electrical conductivity, thermal conductivity, complex dielectric permittivity, electromagnetic radiation, EMR reflection index, EMR absorption index.

your comment: