Expandable Graphite
Size
0.50mm or 0.106mm, etc
Package
25 kg small bags into ton bags
Origin
China
Features
Preservative/Electrical and thermal conductivity, etc.
Application
Fireproof sealing element, flame retardant, refractory brick, etc.
Expandable graphite crystal is a typical layered carbon material. Other heterogeneous particles such as atoms, molecules, ions, and even atomic clusters are inserted into the interlayer of crystalline graphite by physical or chemical methods to form a new layered compound, which is called graphite interlayer compound, namely expandable graphite.
Request a quoteExpandable graphite is a kind of graphite interlayer compound that can decompose rapidly and produce a large amount of gas at a suitable temperature, which makes the graphite expand dozens or even hundreds of times along the c-axis.It is estimated that the market value of expandable graphite will be USD 312 million in 2025
In recent years, expandable graphite functional materials have attracted more and more attention from scientists. It not only maintains some of the original excellent properties of graphite, such as conductivity, heat conduction, high-temperature resistance, corrosion resistance, self-lubrication, and so on but also adds some new special properties, of which the key is its expansibility. Moreover, expandable graphite can expand rapidly in heat or other functions to become expanded graphite, which can be widely used in chemical, mechanical, electronic, metallurgical, and other departments.
According to QYResearch, the global market value of expandable graphite in 2018 was US $214.6 million, which is expected to reach the US $312 million by the end of 2025, with a CAGR of 5.5% from 2018 to 2025. With the expansion of the expandable graphite market, relevant research needs to be further strengthened.
Common preparation methods of expandable graphite.The preparation methods of expandable graphite include chemical oxidation method, electrochemical method, gas phase diffusion method, mixed liquid phase method, melting method, pressurization method, explosion method, etc. At present, chemical oxidation and electrochemical oxidation are two common preparation methods.
At present, some progress has been made in the research of expandable graphite and expanded graphite.Recent research progress in the preparation of expandable graphite, the process of graphite expansion is achieved by mixing oxidant, intercalating agent, and graphite in the molar ratio of 1:1:50, stirring evenly, standing at atmospheric pressure and low temperature, and then the high temperature and high-pressure treatment. Compared with the previous production method, this method has the advantages of simple operation, low production cost, less three waste, and high product yield.
Preparation of graphite intercalation: natural fine flake graphite is used as raw material. After the first drying, oxidant and intercalator are mixed with natural fine flake graphite to saturated state under normal temperature and pressure to form graphite intercalation compound;
Washing treatment: filter the graphite intercalation compound, wash it repeatedly with deionized water until the pH value of the washing solution reaches 6, obtain the sample, and put the sample in the oven for the second drying;
Preparation: expand the sample after the second drying in a muffle furnace at a high temperature for a certain time, and then cool it to room temperature to obtain expanded graphite.
The invention uses a simple chemical intercalation method, which does not involve the process of high temperature and high pressure, and has a safe operation and no danger. By changing the volume ratio of hydrogen peroxide and concentrated phosphoric acid as oxidants and using the environmental friendly insertion agent tannic acid, the morphology and expansion rate of expanded graphene can be adjusted.
