Amino-Functionalization of Graphene Sheets and the Fabrication of Their Nanocomposites

Expandable graphite oxide (EGO) was functionalized with different amine groups after sequential steps as thermal expansion, oxidation, acylation, and amidation. Three types of amino-functionalized graphenes (a-Gphs) were prepared by exfoliating amino functionalized EGOs(a-EGO) through controlled ultrasonication. Fourier transform infrared spectroscopy, elementary analysis, X-ray diffraction, and thermogravimetric analysis separately confirmed the chemical structure of a-EGO. The effect of ultrasonic power on the particle sizes of exfoliated a-EGOs was estimated by dynamic light scattering. Single layered graphene (0.43 nm) was achieved after ultrasonicating at 500 W for 20 min, which was affirmed by the results of atomic force microscopy and transmission electron microscopy. Ultra violet-visible spectroscopy also indicates the good dispersion properties of a-Gphs in these solvents. The thermal properties of composites are obviously increased by adding a-Gphs and a-EGOs as nanofillers. POLYM. COMPOS., 31:1987-1994, 2010. (C) 2010 Society of Plastics Engineers