Imidazole hardeners are a class of hardeners developed in recent years. Imidazole compounds as a new curing agent and accelerator of epoxy resins have a unique advantage: high temperature curing is not required because its curing mechanism is similar to that of tertiary amines, which is anionic catalytic polymerization, but there is no chain transfer like tertiary amines requiring high temperature curing, so medium temperature curing is sufficient. The thermal deformation temperature of the cured material is high, and other properties are similar to those of aromatic amine curing agent. Imidazole curing agents are less alkaline, less volatile and odorless, and much less toxic than aliphatic and aromatic amines. Thermal stability is good, usually they almost do not decompose below 250 ° C.
Imidazole and its modified epoxy curing agent are a very important anionic polymerization epoxy resin curing agent, with small dosage, long application period, medium temperature curing, low volatility, low toxicity or non-toxic, excellent curing properties, excellent bonding strength, excellent heat resistance, mechanical properties and electrical insulation. Now there are many varieties such as 2MI, 2EI, 2E4MI, 2PI and 2P4MI are both excellent curing agents, but also show the unique excellent properties of curing accelerators.
Imidazole and its derivatives are mainly used as curing agents for epoxy resins. With the development of industry, the demand increases year by year, and the modified imidazole curing agent is also commonly used in adhesives, sealants, coatings, potting and sealing materials and composite materials.