Epoxy resin is a kind of polymer with the molecular formula (C₁₁H₁₂O₃)n , which refers to a class of polymers containing more than two epoxy groups in the molecule. It is a polycondensation product of epichlorohydrin with bisphenol A (C₁₅H₁₆O₂) or polyols. Due to the chemical activity of the epoxy group, a variety of compounds containing active hydrogen can open the ring when they react with it, so as to solidify and cross-link to form a network structure, so it is a thermosetting polymer synthetic material.
