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© 2017 Trans Tech Publications, Switzerland. The infrared absorption spectra of aqueous dispersions of carbon nanotubes in the presence of surfactants and alkali metal salts in the frequency range from 1000 cm-1 to 3000 cm-1 have been studied. The possibility of controlling the characteristics of local environment of carbon nanotubes by varying external electrolyte and modulation the surfactant micelle structure has been shown.

© 2016, Springer Science+Business Media New York.The dispersing action of the surfactant (sodium dodecyl sulfate, SDS) on the carbon nanotubes (CNT) in aqueous medium has been studied. Electron microscopy, molecular docking, NMR and IR spectroscopies were applied to determine the physical-chemical properties of CNT dispersions in SDS—water solutions. It was established that micellar adsorption of the surfactant on the surface of carbon material and solubilization of SDS in aqueous medium contribute to improving CNT dispersing in water solutions. It was shown that the non-polar hydrocarbon radicals of a single surfactant molecule form the highest possible number of contacts with the graphene surface. Upon increase of the SDS in solution these radicals form micelles connected with the surface of the nanotubes. At the sufficiently high SDS concentration the nanotube surface becomes covered with an adsorbed layer of surfactant micelles. Water molecules and sodium cations are concentrated in spaces between micelles. The observed pattern of micellar adsorption is somewhat similar to a loose bilayer of surfactant molecules.

The surfactant-base membrane mimetic supramolecular structures and their reaction on the presence of carbon nanotubes were studied. On an example of cetyltrimethylammonium bromide (CTAB) it was shown that CTAB molecules can form structures which in texture, shape and sizes imitate the morphology of biological membranes, - the sheets with a typical size of several tens of micrometers. It has been established that the presence of carbon nanotubes leads both to the change in the characteristic size of the sheets in the direction of their increase, and the appearance of new structural state - the sheets which form the «flower structures» (nanoflowers). This means that the presence of the carbon nanoparticles may change the geometry of the membrane structure, thereby altering membrane properties and thus causing disturbances in the activity of biological organisms.