Determining the dielectric losses in polymers by using Molecular Dynamics simulations

Abstract

In order to increase the energy density in capacitors the properties of dielectric media has to be enhanced. One way of achieving this is to add voltage stabilizing additives, however, these may lead to increased the dielectric losses. In the current study Molecular Dynamics simulations are used to compute dielectric permittivities and losses for a polyethylene system with additives. From the dipole moment of the system the dielectric constant was computed. From the autocorrelation function of the total dipole moment the dielectric losses were computed. In order to decrease the wall clock time of the simulations a multi-scale model was developed which speeds up the calculations. The strengths and weaknesses of this model is discussed and it is concluded that it performs well in determining absolute dielectric permittivities and relative dielectric losses.