A poly(methyl methacrylate)-intercalated graphite oxide/poly(methyl methacrylate) nanocomposite was prepared by emulsion polymerization of methyl methacrylate in the presence of graphite oxide (GO). GO was synthesized by the oxidization of natural graphite powder with KMnO4 in concentrated sulfuric acid. The functional groups and microstructure of the oxidized graphite and the composite were carefully characterized by use of X-ray diffraction, infrared, transmission electron microscopy, and elemental analysis. The electrical conductivity and mechanical properties were also measured. (C) 2004 Society of Plastics Engineers.