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The possibility of stabilizing aqueous dispersions of carbon nanotubes (CNTs) using phenol-formaldehyde resin (PFR) and aminocumulene (AC) is shown. The preliminary oxidation of CNTs contributes to their higher solubility in the presence of these stabilizing agents. The concentration of pristine and oxidized CNTs in weakly alkaline solutions containing 2.5 g/L of PFR is 3.0 and 11.4 g/L, respectively. AC promotes the formation of stable dispersions in acidic media with the concentrations of pristine and oxidized CNTs, respectively, 3.3 and 20.4 g/L. A decrease in the effective sizes of agglomerates of both pristine and oxidized CNTs in the presence of PFR and AC has been shown by dynamic light scattering method. According to TG/DSC analysis and Raman spectroscopy data, it was concluded that the oxygen-containing groups of oxidized CNTs interact with the surfactants used. Schemes for the formation of hydrogen and chemical bonds between CNTs and PFR or AС were proposed, which made it possible to explain the effect of dispersion. [ABSTRACT FROM AUTHOR]

This article discusses the nature of the distribution of intact polyaniline-functionalized graphene nanoplatelets (GNPs) in the surface layer of nanomodified films of ultra-high molecular weight polyethylene (UHMWPE) using a Raman mapping method. On the Raman maps, D, G, and 2D peaks can be observed for the 0.1 wt.% GNPs content in the UHMWPE. In the surface layer of the films containing 1.0 wt.% GNPs, these signals are not detected, thereby indicating the displacement of the nanomodifier into the polymer bulk. In contrast, the polyaniline-functionalized GNPs tend to migrate to the surface of the UHMWPE nanocomposite film and evenly distribute in the surface layer as the concentration increases from 0.1 to 2.0 wt.%. [ABSTRACT FROM AUTHOR]

In the present paper, the features of obtaining a metal oxide Fe–Co/Al2O3 catalyst for the synthesis of carbon nanostructured materials through thermal decomposition are considered. It was experimentally proved that the temperature and duration of the stage of thermal decomposition of the initial components solution significantly affect the catalyst activity in the synthesis of carbon nanostructured materials by the CVD method. It was found that controlling the mode parameters of the thermal decomposition of the initial components solution of the Fe–Co/Al2O3 catalyst, one can not only obtain a catalyst with the required characteristics but also directionally synthesize carbon nanostructured materials over the resulting catalytic systems. During the experiments, rational modes for the implementation of the method for producing catalysts were determined, allowing to form a metal oxide system with a specific surface area of 108 m2/g, the use of which in the synthesis of carbon nanostructured materials leads to the formation of multi-walled carbon nanotubes with an external diameter of 30 nm. [ABSTRACT FROM AUTHOR]