graphene nanostructures were synthesized by hummer method. 1, 3, 5 and 7 wt% of graphene nanostructures were suspended in certain amount of acetone on a mechanical stirrer and stirred then added to epoxy resin. after 4 hours, solution and graphene platelets (gps) were prepared. nanostructures were characterized by x-ray diffraction (xrd), scanning electron microscopy (sem ), fourier transform i...

In this study, the mechanical properties of epoxy nanocomposites with graphene platelets, single-walled carbon nanotubes, and multi-walled carbon nanotube additives were compared at a nanofiller weight fraction of 0.1 +/- 0.002%. The mechanical properties measured were the Young's modulus, ultimate tensile strength, fracture toughness, fracture energy, and the material's resistance to fatigue c...

in the present study, the effect of various weight fractions of graphene nanoplatelet (gpl) on flexural fatigue behavior of epoxy polymer has been investigated at room temperature and generally the temperature was monitored on the surface of specimen during each test. the flexural stiffness of grapheme nano-platelet/epoxy nanocomposites at 0.1, 0.25 and 0.5 wt. % as a main effective parameter o...

Graphene nanostructures were synthesized by Hummer method. 1, 3, 5 and 7 wt% of graphene nanostructures were suspended in certain amount of acetone on a mechanical stirrer and stirred then added to epoxy resin. After 4 hours, solution and Graphene platelets (GPs) were prepared. Nanostructures were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM ), Fourier transform i...

In this study, tip-enhanced Raman spectroscopy (TERS) is used to characterize graphene-like and graphitic platelets composed of a few layers of graphene. Specifically, gap-mode TERS geometry provides a larger enhancement of the local electromagnetic field at the junction formed by a gold sharp tip and a gold substrate. Graphene-like platelets are deposited onto ultra-flat thin gold nanoplates u...

A theoretical model is proposed that describes the effect of graphene platelets pullout on fracture toughness ceramic/graphene composites. The dependences concentration and dimensions are calculated using a yttria-stabilized zirconia (YSZ)/graphene composite as an example. Calculations predict if from ceramic matrix dominant mechanism, then maximum achieved in case longest thinnest possible pla...

We prepared hydrazine-reduced materials from both graphite oxide (GO) particles, which were not exfoliated, and completely exfoliated individual graphene oxide platelets, and then analyzed their chemical and structural properties by elemental analysis, XPS, TGA, XRD, and SEM. Both reduced materials showed distinctly different chemical and structural properties from one another. While hydrazine ...

The development of new mechanical actuators that convert external stimuli such as thermal, light, electrical, or chemical energy to mechanical energy depends on the development of new materials. Reversible mechanical actuators based on carbon nanotubes (CNTs) and hydrogel polymers have suggested applications in robotics, sensors, mechanical instruments, microscopy tips, switches, and memory chi...

Chemically modified graphene platelets, produced via graphene oxide, show great promise in a variety of applications due to their electrical, thermal, barrier and mechanical properties. Understanding the chemical structures of chemically modified graphene platelets will aid in the understanding of their physical properties and facilitate development of chemically modified graphene platelet chem...

We report a remarkably rapid method for assembling pristine graphene platelets into a large area transparent film at a liquid surface. Some 2-3 layer pristine graphene platelets temporally solvated with N-methyl-2-pyrrolidone (NMP) are assembled at the surface of a dilute aqueous suspension using an evaporation-driven Rayleigh-Taylor instability and then are driven together by Marangoni forces....