الفهرس 
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Abstract
The aim of this study is developing graphene/polyamide12 nanocomposites of good
mechanical performance as light-weight structural materials for structural applications
that demand (rigidity and light weight) such as, automotive, aerospace, and wind
turbine technologies. A new facile approach for the gram-scale synthesis of powdery
graphene nanoplatelets from glucose precursor has been developed. This approach
involves one-step hydrothermal treatment of glucose in presence of few milliliters of
ammonia, followed by moderate temperature thermal annealing under the inert
atmosphere. Firstly, reduced graphene oxide (RGO) has been prepared in gram-scale
via hydrothermal treatment of glucose. Upon increasing the vapor/liquid ratio for
aqueous glucose solution within the autoclave system to 3/2, RGO3/2 -rich graphitic
powder, containing small graphene oxide and amorphous carbon contents and having
a spherical morphology, is obtained. Then, the effect of chemical reagent/s combined
with glucose within the autoclave system has been studied (by introducing of few
milliliters of ammonia, ammonia-hydrazine hydrate mixture, HCl and NaOH into the
reaction medium). It is found that the number of H+, produced from the evolved
byproduct hydrogen gas, has a vital role in deoxygenating the aromatic sp2 domains
constituting the graphitic structure. The analyses reveal that increasing the number of
evolved H+ leads to the formation of less oxidized graphitic structure. The number of
evolved H+ is produced from the reagents in the following order: HCl then ammonia
and the maximum number is produced from the ammonia-hydrazine mixture. On the
other hand, it is found that NaOH does not produce any proton. Besides, the evolved
nitrogen gas produced from ammonia and ammonia-hydrazine creates fitted inert
atmosphere to cope any oxygenation process. Accordingly, hydrothermally graphitic
powder resulted from the addition of ammonia-hydrazine mixture, Amm-Hyz-
RGO3/2, represents the RGO sample of the best structural quality among all the
hydrothermally produced graphitic samples with minimum O and amorphous carbon
contents and best structural order interior of the aromatic sp2 domains. Actually, the
quality of the hydrothermally graphitic sample resulted from the addition of ammonia,
Amm-RGO3/2 is nearby to that of the Amm-Hyz-RGO3/2. However, Amm-RGO3/2
formed significantly in larger yield than Amm-Hyz-RGO3/2. Moreover, a flat
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nanoplatelets morphology has been confirmed for Amm-RGO3/2. Accordingly, Amm–
RGO3/2 is considered to be the optimum sample, regarding the quality as well as the
productivity. Afterward, RGO3/2 and Amm–RGO3/2 have been thermally.