Dispersion of Fullerene C60 in Organized Media

Abstract
In the process of manufacturing of dispersions of carbon nanostructures via ultrasound exposure, the use of amphiphilic compounds as dispersing and stabilizing additives is promising. In this paper, the optimal conditions for the ultrasonic dispersion of fullerene C₆₀ in supramolecular organized micellar aqueous solutions of non-ionic surfactants – ethoxylated isononylphenols with varying average degree of ethoxylation were found. By the methods of absorption spectroscopy, dynamic and electrophoretic light scattering, it was established that the use of surfactants increases the content of C₆₀ particles in the dispersion volume by more than 3 times, decreases the average hydrodynamic diameter of the particles and increases stability of the system during storage in 40–50 times. It was revealed that effective values of surfactant concentrations significantly exceed the corresponding values of critical micelle concentration (CMC).
It was established, that the colloidal properties of dispersions and the disaggregation of fullerene particles are influenced by the hydrophilic-lipophilic balance of surfactants, their concentration in solution and the size of micelles. It was shown that homologues with the average ethoxylation degree n = 8 and n =12, have the greatest dispersant and stabilizing effect, correspondingly. The effect of surfactant concentration and the number of oxyethylene groups in dispersing additives on electrokinetic properties and structure of C₆₀ dispersions was revealed. Assumptions about adsorption nature of the interaction of ethoxylated isononylphenols and their associates with fullerene surface have been made. The destruction of the agglomerates of fullerene nanoparticles was confirmed by confocal microscopy data.
Stable dispersions of fullerene C₆₀ can be used for biochemical and biomedical research, in the processes of obtaining nano-modified polymer composite materials using non-toxic and safe water media

Keywords: fullerenes, ethoxylated isononylphenols, surfactants, ultrasonication, absorbance spectroscopy, average hydrodynamic diameter, dispersion, stabilization, electrokinetic potential