Statistical analysis of mechanical properties and electrical conductivity of high density polyethylene composites

Various additives are used in composite production to improve the mechanical performance and electrical conductivity of polymers. In this thesis study, a total of 26 samples based on high density polyethylene (HDPE) were produced using calcite, graphite, crosslinker, ethyl vinyl acetate (EVA) and elastomer. For composite production, extrusion and injection processes were applied to the mixtures prepared according to the response surface method (RSM) experimental design. Experimental data regarding hardness, tensile strength, elongation, rupture strength, yield strength and electrical conductivity of the samples were evaluated by analysis of variance (ANOVA). Accordingly, it was determined that the yield strength was in compliance with the second-order model (quadratic), while the others were in compliance with the first-order (linear) model. Electrical conductivity results were not compatible with any model. According to SEM and EDS results, it was observed that the additives did not exhibit a homogeneous distribution in the HDPE matrix and there was a weak interaction between the particle and the matrix.