Dielectric Properties of Recyclable Epoxy Resins Based on Dynamic Borate Ester Bonds

In this paper, an epoxy resin system based on dynamic boron ester bonds was designed and synthesized, successfully achieving a synergistic enhancement between insulation performance and material recyclability. Experimental results demonstrate that the dielectric loss of the proposed epoxy resin under conventional conditions is significantly lower than that of traditionally anhydride-cured epoxy resins. Meanwhile, its breakdown field strength at ambient temperature has been notably improved. The introduction of dynamic boron ester bonds allows the resin network to undergo topological rearrangement at specific temperatures, thereby endowing the material with excellent reprocessability. After repolymerization, the recycled material retains a breakdown strength retention rate of 90 %. This work provides a novel technical perspective and practical foundation for the recycling and reuse of insulating materials in high-voltage electrical equipment.