Hydroxypropyl methylcellulose synthetic adhesive Powder HPMC

Adhesive Products are generally divided into three types: organic and inorganic adhesives, and metal powder adhesives. Common organic adhesives mainly include: epoxy adhesives, silicone adhesives. The main property difference between them and inorganic adhesives is temperature resistance. The maximum temperature resistance of organic adhesives is usually between 100-250 degrees, and the maximum is generally not more than 400 degrees. The temperature resistance of inorganic adhesives is usually between 600 and 1750 degrees Celsius. Organic adhesives can be soft or rigid, while inorganic adhesives are usually rigid and rigid. Common metal powder adhesives mainly include some low-melting metal powders, whose temperature resistance depends on the melting point of the metal powder.

Organic adhesives mainly include: epoxy adhesive, silicone adhesive, acrylic adhesive.

 

Inorganic adhesives mainly include silicate based adhesives, phosphate based adhesives, aluminates and so on.

 

Gold powder adhesive mainly includes: pure aluminum powder and so on.

 

Among them, organic adhesives are the most widely used, and epoxy adhesives in organic adhesives are closely related to our lives!

 

 

 

Epoxy adhesive

 

Generally, in the absence of oxygen, the thermal decomposition temperature of the epoxy resin body is higher than 300 ° C. When used in air, thermal oxidative decomposition usually occurs at 180 to 200 ° C. When aged at this temperature for a period of time, the strength is even lower. Most alicyclic epoxies are relatively stable below 200℃, but the thermal oxidation damage is more serious than that of bisphenol A epoxies above 200℃. This may be because alicyclic rings are less stable than aromatic rings. The thermal oxidation stability of bisphenol A epoxy cured by aromatic amine is not as good as that of alicyclic A type epoxy cured by alicyclic or aromatic cyclic anhydride. Because there are more hydroxyl groups in the amine cured epoxy structure. Dehydration is easy to occur at lower temperatures. In addition, the N atom on the amine is also more susceptible to thermal oxidation damage. However, hydroxyl groups are rarely formed in the cured products of acid anhydride. However, above 290 ° C, the molecular chain of the epoxy resin of the two curing agents will begin to break. It can be seen from the above that the high temperature resistance of bisphenol A type epoxy resin is poor. The cured product of acid anhydride has higher temperature resistance than that of aromatic amine.

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