How much is the recovery of waste curing agent in Guizhou

Curing temperature and heat resistance of curing agent

The curing temperature of various curing agents is different, and the heat resistance of cured products is also very different. Generally speaking, the curing agent with high curing temperature can be used to obtain the cured product with excellent heat resistance. For addition polymerized curing agent, the curing temperature and heat resistance shall be increased in the following order:
Aliphatic polyamines<alicyclic polyamines<aromatic polyamines<phenolic aldehyde<anhydride

Classification by use
Curing agent can be divided into room temperature curing agent and heating curing agent according to the use. Epoxy resin generally has good performance when cured at high temperature, but coatings and adhesives used in civil construction need to be cured at room temperature due to heating difficulties; Therefore, aliphatic amines, aliphatic epoxides and polyamides are mostly used, especially the coatings and adhesives used in winter have to be used together with polyisocyanates, or polyisocyanates with foul smell are used.

As for medium temperature curing agent and high temperature curing agent, the choice should be based on the heat resistance of the object to be landed and the heat resistance, adhesion and drug resistance of the cured object. Polyamine and anhydride are selected. Because anhydride cured products have excellent electrical properties, they are widely used in electronics and electrical appliances.

The adhesive property, alkali resistance and water resistance of the cured product of aliphatic polyamine are excellent. Aromatic polyamines are also excellent in drug resistance. As the nitrogen element of amino group forms hydrogen bond with metal, it has excellent antirust effect. The higher the amine concentration, the better the antirust effect. Acid anhydride curing agent forms ester bond with epoxy resin, showing high resistance to organic acid and inorganic acid, and its electrical performance generally exceeds that of polyamine.

The variety of curing agent has a great impact on the mechanical properties, heat resistance, water resistance, corrosion resistance, etc. of the cured product. For example, curing agents such as aromatic polyamines, imidazole, and anhydride can cure heat resistant aliphatic polyamines and low molecular polyamide curing agents of epoxy resin; The water resistance of aromatic anhydride cured epoxy resin is better than that of aromatic diamine and aliphatic polyamine curing agents; The triethylenetetramine curing agent has good alkali resistance, but poor acid resistance and formaldehyde solution resistance. The resistance of epoxy resin cured by alicyclic polyamines (such as isophorone diamine) is excellent. Alkali resistance of epoxy resin cured with anhydride curing agent is better than acid resistance. Appropriate curing agent shall be selected according to different uses and performance requirements.

Curing agent can be divided into room temperature curing agent and heating curing agent according to the use. Epoxy resin generally has good performance when cured at high temperature, but coatings and adhesives used in civil construction need to be cured at room temperature due to heating difficulties.

The adhesive property, alkali resistance and water resistance of the cured product of aliphatic polyamine are excellent. Aromatic polyamines are also excellent in drug resistance. As the nitrogen element of amino group forms hydrogen bond with metal, it has excellent antirust effect. The higher the amine concentration, the better the antirust effect.

Curing agent, also known as curing agent, hardener and setting agent, can harden, seal and strengthen concrete; Its variety has a great influence on the mechanical properties, water resistance, heat resistance and corrosion resistance of cured products.