Toughening-type epoxy resin and preparing method and application thereof

The invention discloses a toughening-type epoxy resin and a preparing method and application thereof. The toughening-type epoxy resin is prepared from, by weight, 100 parts of epoxy resin and 10-30 parts of modifying agent. The modifying agent is prepared from a multi-epoxy-group cycloaliphatic epoxy resin and core-shell-structure nanometer rubber particles; the core-shell-structure nanometer rubber particles are added into a matrix epoxy resin, the toughness of the matrix epoxy resin can be greatly improved, the Tg point of the matrix epoxy resin can be reduced, the core-shell-structure nanometer rubber particles are dispersed through the multi-epoxy-group cycloaliphatic epoxy resin, then the dispersed core-shell-structure nanometer rubber particles are added into the matrix epoxy resin, and the Tg of the toughening-type epoxy resin becomes high; when toughening-type epoxy resin is used for a high-voltage switch product, the cracking resistance and the high-and-low-temperature-resistant impact performance of the product can be improved. The toughening-type epoxy resin is high in toughness and Tg, and can be applied to the field of high-voltage switches.