Thin-film particles of graphite oxide 1: High-yield synthesis and flexibility of the particles

Thin-film particles of graphite oxide were synthesized in high yield by the modified Hummers' method, in which a very long oxidation period was combined with a high purity purification process. The particles obtained had an average thickness of several nanometers and an average width of about 20 mum. The yield was 122 wt% based on the raw graphite and the recovery of carbon was 68%. Moreover. excellent flexibility of the particles was observed for the original particle(s) itself, for the particle in matrix polymer, and for two kinds of secondary conformations (lamination-layer-aggregate and random-shape-aggregate). As generally expected and already observed partially, if the affinity between the particle and the dispersion medium was very high, the thin-film particle extended well, though a local crease or a large bend could be generated. At a medium degree of affinity, the particle slightly bent, and at very low affinity, the particle(s) randomly aggregated. (C) 2004 Elsevier Ltd. All rights reserved.