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The influence of the morphology of polyaniline derivatives on the electrical conductivity, sensory sensitivity to air humidity of thin-film structures based on them, and the reaction to ammonia vapors has been investigated. Aniline derivatives, as well as polymers based on them, poly-2-[(2E)-1-methyl-2-butene-1-yl]aniline and poly-2-(cyclohex-2-en-1-yl), were synthesized. Using a scanning electron microscope, the morphology of the surface of thin films obtained from a solution of synthesized polymers by centrifugation on sitall substrates was studied. Studying the nature of morphology is extremely important when creating sensory devices. On the basis of these polymers, samples of resistive thin-film structures were prepared, the dependence of their electrical conductivity on the relative humidity of the air and the dependence of the current passing through the sample with a change in the concentration of ammonia vapors were measured. The influence of the morphology of the surface of the films on the sensitivity of sensors to air humidity has been experimentally revealed and the prospects of using the studied films in humidity sensors have been shown. According to the experimental data, it can be seen that poly-2-[(2E)-1-methyl-2-butene-1-yl] aniline film has the highest conductivity at the same values of relative humidity.

The article is devoted to the topical problem of studying the supramolecular structure of petroleum asphaltenes. They are the prospective materials for molecular electronics and nanotechnology. At present, the properties of asphaltenes at the supramolecular level are studied by various experimental methods and methods of mathematical modeling. As objects of a research the asphaltenes concentrated in residual fractions of vacuum distillation of the West Siberian oil with a temperature of boiling more than 500 °C were used. Asphaltenes of samples allocated with dissolution of fractions in toluene with the subsequent sedimentation by surplus of n-heptane by Golde's technique. Results of ASM-researches show existence of steady units from nanoclusters of oil asphaltenes in the form of structures of an ellipsoidal form about 4.5 nm high and with a lateral size up to 100 nm. The research of supramolecular structure of nanoclusters of oil asphaltenes in the GAUSSIAN software package is executed. Calculation was carried out by method of molecular mechanics of MM with full optimization of geometry. The structure of molecular fragments of a nanoparticle of asphaltenes is defined according to data of 1H, 13C NMR and IR of spectroscopy and the chemical analysis earlier. These data will be agreed with results of works on identification of molecules of asphaltenes by the ASM method of high resolution. Follows from calculations that the nanoclusters having an appearance of quasicrystal reniform structures with number of molecular fragments from 2 to 10 are steadiest, at the same time the distance between the planes of molecular fragments of a nanocluster is in the range from 3.53 up to 3.67 Å, and diameter of particles 11-40 Å. Data on height of nanoclusters will well be agreed with results of ASM-researches for small structures. Calculations of supramolecular structure of oil asphaltenes by method of molecular mechanics show considerable energy of intermolecular interaction of structural molecular fragments of 60-118 kJ/mol that testifies to a possibility of self-assembly of ordered structures from these nanoparticles visualized by means of ASM. The received results are confirmed by data of the X-ray diffraction analysis and electric measurements on energy of activation of hopping conductivity (129.58 kJ/mol) and also the carried-out earlier thermodynamic calculations. As appears from calculations, the increased stability of quasicrystal structure which arises, most likely, as a result of transfer of a charge between fragments as molecules have the low potential of ionization and high affinity to an electron is characteristic of nanoclusters.