Flame retardant mechanism of aluminum hydroxide in epoxy resin

Aluminum hydroxide is an amphoteric hydroxide, which reacts with both acids and bases, is non-toxic, does not contain halogens, and does not produce corrosive substances. Its crystallization is perfect, and in epoxy resin, aluminum hydroxide has a special effect of flame retardant reaction. Properly increasing the proportion of aluminum hydroxide can effectively improve the oxygen index, and also enhance the arc resistance and arc trace resistance of epoxy resin. The increase of the amount of aluminum hydroxide can reduce the amount of smoke emitted when the epoxy resin burns, aluminum hydroxide has a good smoke elimination effect, and the flame retardant aluminum hydroxide has a good flame retardant effect on the epoxy resin system. Aluminum hydroxide decomposes by heat and absorbs heat, which inhibits the burning of epoxy resin. The dehydration of aluminum hydroxide generates a large amount of water vapor, which reduces the temperature and dilutes the concentration of oxygen and flammable gas, thus preventing the burning of epoxy resin. and smoke suppression effect.