DIELECTRICAL ANALYSIS OF COMPOSITE MATERIALS WITH RECYCLED CARBON FIBERS

A series of thin epoxy resin samples were prepared. Short recycled carbon microfibers in concentrations from Owt% to 33wt% were used as composite fillers. The geometry and structure of these fillers were characterized using SEM and Raman DXR microscopy images. It has been found that the dielectric properties of composites strongly depend on the RCF content and show an increase in values at and above the percolation threshold. Below the percolation threshold, the distance between the fibers is large enough so that there is no interaction of the local fields created by the adjacent fibers and the dielectric constant in this region increases slowly. As the filler concentration increases, the Maxwell Wagner effect increases and leads to a sharp increase in the real permittivity values. Furthermore, it was found in this work that the permittivity increases with increasing concentration of particles even after reaching the percolation threshold over the entire frequency band.

Automated summary

The study found that the dielectric properties of composite materials are significantly affected by the content of recycled carbon microfibers, with an increase in permittivity values above the percolation threshold. As the filler concentration increases, the real permittivity values sharply rise due to the Maxwell Wagner effect.