On the dielectric properties of bisphenol A and F epoxy resins blends based on molecular dynamics

Bisphenol A and F epoxy resins are often used as the primary insulation in power equipment. This paper investigates the influence of network structure on the dielectric properties of bisphenol A, bisphenol F epoxy resin and their blends. The results show that substituting isopropyl with methylene in epoxy resin enhances the molecular chain packing efficiency, thus limiting the polarization effect while reducing glass transition temperature (Tg). As the content of bisphenol F resin in the blends increases, the polarization loss of the blends continues to decrease, to even lower than that of bisphenol F resin. For the blend containing 20% bisphenol F resin, the Tg and AC breakdown strength at high temperatures are higher than that of bisphenol A resin. Furthermore, based on molecular dynamics simulation, the reason for the limited polarization effect of the blends is further discussed.