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The paper considers the possibility of using integrated multifunctional additives based on carbon nanotubes and zeolites (natural and synthetic) in construction materials. The nanotubes were produced by catalytic chemical vapor deposition. The streamlined modification of the zeolite structure was performed by impregnating initial materials with a nanotubes-supported catalyst. The present experimental research focused on studying the effect of the synthesized nanomodifying additive on the physicomechanical properties of a composite construction material. Based on the obtained data, it was assumed that when entering the concrete structure, zeolite acts not only as mineral additive but also as nanotubes carrier under the chosen nanomodification conditions for the construction material, thereby allowing for uniform distribution of carbon nanoparticles in the composite matrix; on the other hand, the adsorption properties of zeolite can be reinforced by the presence of carbon in the structure. Structures of nanomodifying zeolites and obtained building composite were evaluated by scanning electron microscopy (SEM). Electron micrographs of the objects makes it possible to explain the processes of formation of the concrete structure, nanomodified complex multifunctional additive based on synthetic and natural zeolites and carbon nanomaterial.

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]