Additives influence on the high density polyethylene dielectric strength

In this work, the effect of pigments (titanium dioxide and carbon black) and chemical additives (UV stabilizer and antioxidant) incorporation on dielectric strength of high-density polyethylene (HDPE) was studied A voltage ramp of 500V/sec was applied to specimens (thin films). The results where analysed by the Weibull distribution. The shape and scale parameters of the Weibull distribution were calculated by Graphical and Maximum Likelihood methods It was possible to conclude that: a) the carbon black is a critical factor as to the dielectric strength; b) the point most susceptible to channel formation is that of carbon black agglomeration; c) The β shape parameter of the Weibull statistics, when determined by Graphical method may represent scattering of dielectric strength results and this scattering is related to the dispersion of carbon black inside.