▎ 摘　　要

NOVELTY - The method for exfoliating a layered material to produce nano-scaled graphene platelets having a thickness smaller than 1 mu m, comprises subjecting a layered material to a gaseous environment at a temperature and a pressure to cause gas species to penetrate into the interstitial space between material layers to form a gas-intercalated layered material (10), and subjecting the gas-intercalated layered material to a second pressure, or a second pressure and a second temperature to allow gas species residing in the interstitial space to exfoliate the layered material to produce the platelets. USE - The process is useful for exfoliating a gas-intercalated layered material to produce nano-scaled platelets (claimed). ADVANTAGE - The process economically produces large quantities of nano-scaled graphene platelets with a uniform thickness. DETAILED DESCRIPTION - The method for exfoliating a layered material to produce nano-scaled graphene platelets having a thickness smaller than 1 mu m, comprises subjecting a layered material to a gaseous environment at a temperature and a pressure to cause gas species to penetrate into the interstitial space between material layers to form a gas-intercalated layered material (10), subjecting the gas-intercalated layered material to a second pressure, or a second pressure and a second temperature to allow gas species residing in the interstitial space to exfoliate the layered material to produce the platelets, and air milling, ball milling, mechanical attrition and/or sonification to separate and/or reduce a size of the platelets. The layered material comprises particles with a dimension smaller than 1 mu m. The platelets comprise single graphene sheets having a thickness of 0.34 mm. The second pressure is lower than the first pressure and second temperature is higher than first temperature. The step of subjecting the layered material comprises placing the material in a sealed vessel containing a pressurized gas and opening the vessel to partially or totally release the gas. After gas release, placing the gas-intercalated material in a heated zone or subjecting the gas-intercalated material to microwave or dielectric heating. The layered material reacts with a gas in the environment. The platelets are in a liquid to form a suspension or in a monomer- or polymer-containing solvent to form a nanocomposite precursor suspension. The suspension is converted to a mat or paper or the nanocomposite precursor suspension to a nanocomposite solid. The platelets are mixed with a monomer or polymer and converting the mixture to obtain the nanocomposite solid. The graphite oxide is partially or totally reduced after the formation of the suspension. The layered material is placed in a sealed vessel. Vaporizing a liquid inside the vessel produces the gas environment. DESCRIPTION OF DRAWING(S) - The drawing shows an apparatus for producing nano-scaled graphene platelets. Layered material (10) Sealed vessel (12) Tubing (18) Pressure gauge (20) Gas regulator (22) Gas cylinder. (24)