The performance of expanded vermiculite is determined by its own structure. After processing, expanded vermiculite is developed according to the functional characteristics of concrete structure in combination with its own properties. It combines the advantages of various fire retardant materials and is therefore highly praised by Chinese people. After being calcined at high temperature, the volume of vermiculite can rapidly expand several times to dozens of times. The average volume weight of expanded vermiculite is 100~130kg/m3. It has a small air compartment, which can keep heat, insulate heat, absorb sound and resist frost corrosion. Therefore, it is suitable for use in refractory materials. Vermiculite will expand when it meets fire, and after expansion, it will protect the concrete structure inside, thus improving the fire resistance limit of concrete and achieving the effect of fire prevention. The advantages of expanded vermiculite in fire prevention are as follows: ① high bonding strength ② good water resistance ③ thin coating ④ high fire resistance time limit ⑤ good physical and chemical performance.

Vermiculite has the effect of fire prevention, which is the nature of vermiculite. However, unprocessed vermiculite raw ore and vermiculite flakes will expand after encountering high temperature, so in many applications, expansion will occur after high temperature, affecting the use of vermiculite. Therefore, it is suitable to use expanded vermiculite in fire prevention. Expanded vermiculite not only has the effect of fire prevention but also has the effect of heat insulation at high temperature. Expanded vermiculite can withstand 1700 degrees of high temperature without melting. Vermiculite has been widely used in tunnel fire prevention and fire prevention coatings. Expanded vermiculite is widely used in thermal insulation materials, fire prevention materials, seedling cultivation, flower planting, tree planting, friction materials, sealing materials, electrical insulation materials, coatings, plates, paints, rubber Refractory, hard water, smelting, construction, shipbuilding, chemical and other industries.