Toughened phenolic adhesive, and preparation method and application thereof

The invention provides a toughened phenolic adhesive, and a preparation method and application thereof. Specifically, the toughened phenolic adhesive is prepared from the following raw materials: a phenolic adhesive, nitrile rubber, a modifier and a dispersant. The invention also provides the preparation method of the toughened phenolic aldehyde adhesive. The invention further provides a toughened resin film prepared from the toughened phenolic adhesive and glass cloth, and application of the toughened resin film as a toughened strain transition layer. The selected phenolic adhesive serves as a stress concentration center on a metal and composite material interface, a large number of crazes and shear bands can be induced, energy generated by interface resin curing can be consumed and absorbed, the expansion/shrinkage difference caused by mismatching of material linear expansion can be filled, the interface debonding problem is avoided, and the temperature resistance level is improved through the modifier; and