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Epoxy resin is a kind of organic compound with two or more epoxy groups in its molecule. Its relative molecular weight is not high except for a few. The molecular structure of epoxy resin is characterized by the active epoxy group in the molecular chain, which can be located at the end, middle or ring-like structure of the molecular chain. Because of the active epoxy group in the molecular structure, they can react with various curing agents to form insoluble polymer with three-way network structure. All the polymer compounds containing epoxy group in molecular structure are called epoxy resin. The cured epoxy resin has good physical and chemical properties. It has excellent bonding strength, good dielectric properties, small variable shrinkage, good dimensional stability, high hardness, good flexibility, and is stable for alkali and most solvents. Therefore, it is widely used in various departments of national defense and national economy as castable, impregnated and laminated materials , adhesives, coatings, etc.