Composite insulating material based on dielectrophoretic force orientation and its preparation method

Abstract

A composite insulating material based on dielectrophoretic force orientation and its preparation method are provided. The method includes: S, preparing dielectric composite microspheres with a dielectric epoxy resin as a core and a hexagonal boron nitride sheet as a shell; S, dispersing the hexagonal boron nitride sheet and the dielectric composite microspheres in an organic solvent to obtain a dispersion liquid, and adding an epoxy resin, an epoxy resin curing agent, and an epoxy resin accelerator to the dispersing liquid, and evaporating the organic solvent to obtain a composite substrate; S, pouring the composite substrate into a container, wherein an upper surface and a lower surface of the container are connected with electrodes, respectively, transferring the container to a vacuum oven, and connecting a power supply of the container to adjust a voltage amplitude and a frequency of the electrodes, conducting dielectrophoretic force orientation on the dielectric composite microspheres in the composite substrate, so as to cause the dielectric composite microspheres to arrange along a direction of electric field; S, increasing a temperature of the container to cure the composite substrate, cutting off the power supply to the container after curing, and obtaining the composite insulating material.