Single-component halogen-free flame-retardant epoxy adhesive and preparation method thereof

The invention relates to a single-component halogen-free flame-retardant epoxy adhesive and a preparation method thereof. The single-component halogen-free flame-retardant epoxy adhesive comprises a component A and a component B with the mass ratio being 1: (0.1-0.4), wherein the component A comprises epoxy resin, DB resin and an organic solvent with the mass ratio being 100: (10-30): (60-100); and the component B is formed by reaction of dicyandiamide and 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-oxide with the molar ratio being 1:1. The single-component halogen-free flame-retardant epoxy adhesive and the preparation method have the advantages that the comprehensive performance is excellent, the sources of the materials are convenient, the preparation process is simple, the cost is low, the application to bonding of base materials such as composite materials and rubber based on metal, plastic, ceramic, glass and resin can be achieved and the application prospect is wide.