Graphite nanoplatelets and compositions

Abstract

Disclosed are graphite nanoplatelets produced by a process which comprises thermal plasma expansion of intercalated graphite to produce expanded graphite followed by exfoliation of the expanded graphite, where the exfoliation step is selected from ultrasonication, wet milling and controlled caviation and where greater than 95% of the graphite nanoplatelets have a thickness of from about 0.34 nm to about 50 nm and a length and width of from about 500 nm to about 50 microns. The intercalated graphite is intercalated for example with a mixture of sulfuric and nitric acids. The plasma reactor for example employs an RF induction plasma torch. All three exfoliation methods are performed in an organic solvent or water. The exfoliation steps may be performed with the aid of for example a nonionic surfactant. Also disclosed are plastic, ink, coating, lubricant or grease compositions comprising the graphite nanoplatelets.

Dependencies are inferred from the claim text.