Expandable graphite is heated at a high temperature can be rapid expansion, the expansion in multiples of up to several times to several hundred or even thousands of times, after the apparent volume of expanded graphite of 250 ~ 300mL / g or greater, expanded graphite exhibits wormlike , tenths of a millimeter to several millimeters in size between the inside with a large number of unique network-like pore structure, known as expanded graphite or graphite worms, expanded graphite has a lot of special excellent performance. Expandable graphite and extruded from expanded graphite, can be used in iron and steel, metallurgy, petroleum, chemical machinery, aerospace, atomic energy and other industrial sectors, broad range of applications. For example, the expandable graphite can be used as a flame retardant for plastics fire, fire retardant anti-static coating and other composite materials and products;
Expandable graphite can also be used as multi-band stealth Smokes and shielding materials, widely used in the military field; made of expanded graphite flexible graphite products known as the world's "King of the seal." In the mechanical seal, fire blocking material has an extremely important role in the field; expanded graphite in the field of environmental protection can be used as a material for sucking waste oil recycling and wastewater treatment microbial carrier.
Expandable graphite are two major categories of chemical oxidation and electrochemical preparation methods. Currently, chemical oxidation and electrochemical measurements in industry have been applied. Among them, the chemical oxidation is the industrial application of the largest and most sophisticated methods, the general process: take a certain amount of natural graphite flake, with constant stirring to add an oxidizing agent and intercalant solution, at a certain temperature of the reaction after a certain time, washed with water to neutral, filtration dewatering, drying, expandable graphite.