Influence of the conductive network creation on electrical, rheological, and mechanical properties of composites based on LDPE and EVA matrices

Electrically conductive polymeric composites are more and more popular as an object of scientific research and as a material applied in different branches of electric, electronic, and heating industry. Complex knowledge of their properties and behavior is needed to take full advantage of the application of these materials. This study focuses on the relationship between the polymeric matrix properties and the process of creating the conductive network within a composite. Two types of composites, based on low‐density polyethylene (LDPE) and poly(ethylene‐co‐vinyl acetate) (EVA), filled with 10–20 wt% of conductive carbon black, have been prepared. Resulting composite samples have been subjected to different tests, including uniaxial drawing test, rotational rheology, and dielectric spectroscopy in order to evaluate the relationship between their composition and properties. It has been observed that creation of the filler network is easier in case of more linear and polarEVAmatrix, whereas electrical and rheological percolation threshold values are higher in the case of the composites containing branchedLDPEmatrices. Therefore, it can be concluded that the process of creation of conductive filler network and the pattern of changes of mechanical, rheological, and electrical properties are vastly influenced by the inherent properties of the polymeric matrix, that is, its branching level and polarity.