Research on formulation system of high thermal conductivity and low viscosity epoxy resin for dry-type transformers

In this study, bisphenol A epoxy resin (DGEBA) was used as the resin matrix, methyl tetrahydrophthalic anhydride (MTHPA) as the curing agent, phenol as the promoter, and boron nitride as the filler. The variation characteristics of the viscosity and thermal diffusivity of the epoxy anhydride system after introducing boron nitride filler were studied by viscometer and laser thermal conductivity meter. The relationship between the viscosity and temperature of the epoxy anhydride system after adding 0%, 1%, 2%, and 5% concentration of boron nitride filler was analyzed during the curing process, and the relationship between the thermal diffusivity and temperature after adding 1%, 2%, and 5% concentration of boron nitride filler. The results show that the viscosity increases with the increase of boron nitride concentration, and the thermal diffusivity increases with the increase of boron nitride concentration. When adding 2% concentration of boron nitride, the viscosity is relatively low and the thermal diffusivity is relatively large. This provides a reference for developing epoxy resin composites with low viscosity and high thermal conductivity in dry transformers.