curing agent can be divided into normal temperature curing agent and heating curing agent according to the purpose. Epoxy resins generally have excellent performance when cured at high temperatures, but coatings and adhesives used in civil engineering and construction are difficult to heat and need to be cured at room temperature; therefore, aliphatic amines, alicyclic mirrors, and polyamides are mostly used, especially in winter Coatings and adhesives have to be used in combination with polyisocyanates, or polythiols with malodorous odors must be used.

　　"As for the medium-temperature curing agent and the high-temperature curing agent, they should be selected based on the heat resistance of the object to be adhered and the heat resistance, adhesiveness, and chemical resistance of the cured product. The focus of selection is polyamines and acid anhydrides. Because the cured acid anhydride has excellent electrical properties, it is widely used in electronics and electrical appliances.

　　Aliphatic polyamine cured product has excellent adhesion, alkali resistance and water resistance. Aromatic polyamines are also excellent in chemical resistance. Since the nitrogen element of the amino group forms a hydrogen bond with the metal, it has an excellent anti-rust effect. The higher the amine concentration, the better the anti-rust effect. The acid anhydride curing agent and epoxy resin form an ester bond, which shows high resistance to organic and inorganic acids, and its electrical properties generally exceed those of polyamines.