Different Series of Epoxy Curing Agents and Their Characteristics
Each type of curing agent has its own advantages and is chosen based on the specific requirements of the application, such as cure speed, temperature resistance, chemical resistance, flexibility, and adhesion properties. Formulators often select curing agents based on these factors to achieve the desired performance characteristics in the final epoxy resin system.
1. Amine curing agents : Including aliphatic amines, aromatic amines, such as ethylenediamine (EDA), triethylphosphamide (TEPA), aniline, etc. This type of curing agent usually reacts with epoxy resins between amine and epoxy groups to form amino addition products, thereby curing the epoxy resin.
Features : Usually cures quickly and can effectively cure epoxy resins at room temperature.
Application : Commonly used in situations where rapid curing is required, such as coatings, adhesives, etc.
2. Acid anhydride curing agent : Mainly epoxy resin reacts with acid anhydride curing agent (such as formic anhydride) to generate epoxy group ring-opening products, thereby curing epoxy resin.
Features : Cures under mild conditions and is less affected by ambient humidity and moisture .
Application: Suitable for curing requirements in high humidity environments, such as concrete surface coatings .
3. Phenolic curing agent : Epoxy resin reacts with phenolic compounds, usually through the reaction of phenolic hydroxyl groups with epoxy groups of epoxy resin to form a cross-linking structure to cure epoxy resin.
Features : The cured product has excellent heat resistance and chemical resistance, and is especially suitable for high temperature and chemical corrosion environments.
Application : Used to prepare heat-resistant and chemical-resistant coatings, composite materials, etc.
4. Vulcanization curing agent : This type of curing agent is formed by the reaction of epoxy resin with active sulfur compounds (such as carbon disulfide), forming thioether bonds to cure the epoxy resin.
Features : The cured product usually has excellent flexibility and wear resistance, suitable for applications requiring weather resistance and abrasion resistance.
Application : Commonly used in adhesives, sealants and other fields that require flexibility and weather resistance.
5. Cationic curing agent : Epoxy resin reacts with compounds containing cationic active groups, such as carbamates, epoxy hydroxymethyl compounds, etc., to form a cured product through a ring-opening reaction.
Features : Fast curing speed and can be cured at low temperature.
Application : Mainly used in situations where the ambient temperature is low or rapid curing is required, such as electronic packaging materials, adhesives, etc.