The curing temperature of various curing agents is different, and the heat resistance of cured products is also very different. Generally speaking, the use of curing agent with high curing temperature can obtain excellent heat resistant curing materials. For addition polymer-based curing agents, curing temperature and heat resistance are increased in the following order: aliphatic polyamines < aliphatic polyamines < aromatic polyamines ≈ phenolics < anhydride.

The heat resistance of the curing agent is generally at the level of aromatic polyamines. The heat resistance of anionic polymerization (tertiary amine and imidazole compounds) and cationic polymerization (BF3 complex) is basically the same, which is mainly due to the formation of ether-bond bound network structure in spite of the different reaction mechanism at the beginning.

The curing reaction is a chemical reaction, which is greatly affected by the curing temperature. When the temperature increases, the reaction speed speeds up and the gel time becomes shorter. The log value of gelation time generally shows a straight downward trend with the increase of curing temperature, but the curing temperature is too high, the properties of curing materials often decline, so there is an upper limit of curing temperature. A temperature that compromises the curing speed and the properties of the cured material must be chosen as the appropriate curing temperature.

Curing agent can be divided into four categories according to curing temperature: curing temperature of low temperature curing agent is below room temperature; Curing temperature of room temperature curing agent is room temperature ~ 50℃; Medium temperature curing agent is 50 ~ 100℃; The curing temperature of high temperature curing agent is above 100℃. There are few kinds of curing agent belonging to low temperature curing type, such as polyol type, polyisocyanate type, etc. The T-31 modified amine and YH-82 modified amine developed and put into production in China can be cured below 0℃. There are many kinds of room temperature curing type: aliphatic polyamines, aliphatic polyamines; Low molecular polyamide and modified arylamine. It belongs to the intermediate temperature curing type of a part of the alicyclic polyamines, tertiary amines, squints and boron trifluoride complex. Belong to the high temperature type of curing agent are aromatic polyamines, anhydride, formic phenolic resin, amino resin, dicyandiamide and hydrazide.

For high temperature curing system, curing temperature is generally divided into two stages, using low temperature curing before gel, after reaching the gel state or slightly higher than the gel state, and then high temperature heating for post-cure (post-cure), relative to the previous segment curing (pre-cure).

The epoxy resin must react with the curing agent to form a three-dimensional structure to be of practical value. Therefore, the structure and quality of curing agent will directly affect the application effect of epoxy resin. The research and development of curing agent abroad is far more active than that of epoxy resin. Compared with epoxy resin, there are more kinds of curing agent, and the confidentiality is very strong. Each development of a new curing agent can solve a problem, is equivalent to the development of a new epoxy resin or open up a new use of epoxy resin. It can be seen that the development of new curing agent is far more important than the development of new epoxy resin.