For the first time, the interaction of polyvinyl alcohol and a copolymer of sodium salts of styrenesulfonic and maleic acids in aqueous solutions has been studied using the techniques of static and dynamic light scattering and capillary viscometry. It has been shown that hydrogen-bonded complexes are formed between them, with compaction of polyvinyl alcohol coils occurring in dilute solutions and additional structuring of the solution in semidilute solutions. The activation parameters (enthalpy and entropy) of viscous flow have been assessed, confirming the formation of the complexes. The concentration regimes of solutions of polyvinyl alcohol, the copolymer, and the complexes have been studied. It has been shown that the semidilute entanglement-free regime disappears in solutions of the complexes.

Complexation in aqueous salt-free semidilute solutions of poly(styrenesulfonic acid) and poly(ethylene oxide) leading to the formation of soluble poly(styrenesulfonic acid)–poly(ethylene oxide) complexes is studied. It is shown that the interaction of the components in such complexes significantly weakens with an increase in temperature, as well as with a decrease in the poly(ethylene oxide) chain length. Using viscometry and light scattering, it is demonstrated that, in dilute aqueous and aqueous-saline solutions, no complexes are formed between poly(styrenesulfonic acid) and poly(ethylene oxide) and the system is a compatible mixture of the polymers in a common solvent.

The oxidative polymerization of aniline is studied for the first time in the presence of sulfonated poly(2,6-dimethyl-1,4-phenylene oxide). The polymerization leads to the formation of polyaniline-sulfonated poly(2,6-dimethyl-1,4-phenylene oxide) interpolyelectrolyte complexes in which polyaniline is in the protonated form (as emeraldine salt). It is shown that the polyaniline–sulfonated poly(2,6-dimethyl-1,4-phenylene oxide) complexes, depending on their composition, have either only proton conductivity from 0.015 to 0.1 S/cm, or mixed electronic-proton conductivity (10 –6 S/cm electronic conductivity and 0.015 S/cm proton conductivity), or only electronic conductivity (up to 10 –2 S/cm).

Core–shell polyaniline–latex particles have been obtained via oxidative polymerization of aniline hydrochloride in the presence of charged polystyrene latex. The polymerization conditions have been determined under which polyaniline is predominantly formed on the surface of latex particles to yield closed shells. The dependence of the electrical conductivity of the resulting particles on the initial concentration of aniline hydrochloride in the polymerization medium has been studied. Stable aqueous dispersions of polyaniline–latex particles have been prepared by modifying the particles with sodium 3-mercaptopropane sulfonate.

The effect of surface of multiwall carbon nanotubes on the course of oxidative polymerization of aniline has been studied. In the presence of amorphous carbon fragments at the nanotubes surface, the polymerization at the monomer: nanotubes mass ratio of 10 : 1 yields the composite based on polyaniline and carbon nanotubes. At the same components ratio, carbon nanotubes purified of amorphous carbon inhibit polymerization of aniline, and the process results in oxidation of the nanotubes surface; however, at the lower purified nanotubes content the polymerization proceeds to give the polyaniline/nanotubes composite. Purification of the nanotubes of amorphous carbon significantly enhances electrochemical stability of their composites with polyaniline.

Copolymers of various compositions have been synthesized via copolymerization of aniline with 3,4-ethylenedioxythiophene in the presence of a poly(4-styrenesulfonic acid) matrix, and a mechanism of copolymerization has been suggested. It has been shown that the synthesized copolymers are included in non-stoichiometric interpolyelectrolyte complexes with matrices stabilized by salt bonds and nonionic interactions. The copolymers of aniline and ethylenedioxythiophene possess electrical conductivity and can enter into redox and acid-base reactions.

Three-component systems containing multi-walled carbon nanotubes and silver nanoparticles dispersed in aqueous solutions of polyacrylic acid (M 2000 and 250000) have been studied by electronic absorption spectroscopy and transmission electron microscopy. The studied dispersions were stable during at least several months. Size of silver nanoparticles prepared in the absence and in the presence of the carbon nanotubes has been compared; the effect of polyacrylic acid molecular mass on silver nanoparticles size has been addressed as well.

Polymethylmethacrylated oligoaniline was synthesized by methylmethacrylate radical polymerization in the presence of oligoaniline. By means of IR-spectroscopy polymethylmethacrylated oligoaniline was characterized and its degree of oxidation was showed to be conserved. With the use of cyclic voltammetry its electroactivity was found to be preserved after modification.

Conformational properties of DNA have been studied by scanning probe microscopy and the advantages of this method have been shown for the study of biopolymer morphology. It has been shown that in aqueous-alcohol solutions the linear DNA has the toroid-like conformation without any compacting agents. The conformational transition of the supercoiled DNA into the unfolded circle occurs under the cyclic DNA-surfactant interaction, Morphology of linear DNA in the complex with a surfactant has been determined, It has been assumed that the toroid-like conformation of linear DNA is energetically favorable when the DNA charge is neutralized.

The published data on the interaction of DNA macromolecules with cationic amphiphiles (surfactants) are analyzed. The effect of the structure of surfactant molecules on their interaction with DNA and the structure of DNA-surfactant complexes is examined. The unique property of DNA molecules to preserve the double-helix conformation in complexes is considered. The structure of DNA-surfactant complexes in aqueous and organic solutions is discussed, and examples of the possible application of these complexes are presented.

The functionalization of multiwalled carbon nanotubes (MWCNTs) with sulfanilic acid through the diazotization reaction, which yielded the covalent bonding of sulfo groups to the nanotube surfaces, was performed. Stable aqueous nanotube dispersions were obtained. The sizes of functionalized nanotubes in aqueous salt and salt-free solutions and their hydrodynamic characteristics were measured by dynamic light scattering. The data were compared with the data of scanning electron microscopy.