The expanded graphite can expand by 150~300 times in an instant at high temperature, changing from lamellar to worm-like, so that the structure is loose, porous and curved, the surface area is enlarged, the surface can be enhanced, and the adsorption of flake graphite is enhanced. The worm-like graphite can be self-imbedded, which increases its softness, resilience and plasticity. Expanded graphite is a high quality material for flexible graphite board and various sealing parts. It is widely used in machinery, petroleum, chemical industry, metallurgy, navigation, aerospace, transportation and other industrial fields.
Expanded graphite property
Expansive graphite material, also known as flexible graphite material, is a crystalline compound that USES physical or chemical methods to insert non-carbonaceous reactants into graphite layers and combines them with the hexagon network plane of carbon elements while maintaining the graphite-laminated structure. Not only does it keep graphite high temperature resistance, corrosion resistance, can withstand the neutron flux, x rays, and gamma irradiation for a long time, low friction coefficient, good self-lubrication, conductive thermal conductivity, and the anisotropy and other excellent physical and chemical properties, but due to the interaction of insert material and graphite layer presents the original graphite and intercalated materials do not have new performance, overcoming the natural graphite brittleness and impact resistant bad faults. Graphite with the interlayer compounds in high temperature, interlayer compounds will decompose, produce a kind of the graphite layer between the C axis of thrust, thrust is greater than the adhesion strength between the layers of graphite particles, under the action of the thrust, graphite layers was away, so that the graphite particles along the C axis high inflation, the expansion of the formation of vermicular graphite. Graphite layer and layer can be "embedded" into chemical substances and have expansibility. If the graphite can be treated with sulfuric acid, the graphite expands at high temperature after drying, which is caused by the embedding of sulfuric acid molecules into the graphite layer. The expansion of the expanded graphite flake characteristics different from other expansion agent, heated to a certain temperature, due to the absorption in interlayer matrix compound decomposition, expanded graphite began to swell, referred to as the initial temperature, completely at 1000 ℃, big volume. The expansion volume can be more than 200 times as large as it was at the beginning. Due to its excellent properties of compression, resilience, self-stickiness, self-lubricating and low density, expanded graphite components are widely used in petroleum, chemical industry, machinery, metallurgy, electric power, light spinning, instrumentation, electronics, nuclear industry, aerospace, military industry, medicine and transportation.