Formation and morphological characteristics of selenium-containing nanostructures based on rigid-chain cellulose derivatives

Nanostructures arising from the reduction of ionic selenium by a selenite-ascorbate redox system in aqueous solutions of oxyethyl cellulose, methyl cellulose, and carboxymethyl cellulose have been studied by using a set of optical methods (flow birefringence and static and dynamic light scattering) and viscometry. The adsorption of a substantial amount of macromolecules (up to 3200) on selenium nanoparticles has been experimentally discovered. This effect leads to the formation of superhigh-molecular-mass spherical nanostructures with a high density of the polymer shell. The thermodynamic state of solutions of nanostructures has been characterized. In the region of occurrence of stable dispersions, the values of the free energy of macromolecule-selenium nanoparticle interaction have been calculated for polymer nanostructures. Radii of amorphous selenium nanoparticles occurring in the nuclei of nanostructures and the thickness of the polymer shell have been estimated. Given the fixed molecular mass and comparable rigidity of a polymer matrix, the structure of the monomer unit of the cellulose derivative defines the morphology of the nanostructure being formed.