Permittivity estimation of hydrocarbon-based thermosetting resin using quantum chemical calculation

In recent years, development of computers and progress of calculation algorithms promote understanding of the various mechanisms of characteristics of electrical insulating materials using quantum chemical calculation. This paper deals with quantum chemical calculation of the relative permittivity εr of dicyclopentadiene and tricyclopentadiene resins expected as the next generation electrical insulating materials based on density functional theory and Clausius-Mossotti's, Onsager's or Kirkwood's equation. As a result, estimated values of the relative permittivity are found to reasonably agree with experimental ones. In addition, we investigate the influence of the number of repeating units in the molecular structure on εr. As a result, it is found that the estimated εr is almost independent of the number of repeating units.