The purpose of the work is to characterize the lubricants based on Llitol-24 and synthetic solidol with additives copper(II) carboxylates when using them in friction nodes in loading conditions and temperature. The lubricant compositions with additives copper(II) carboxylates based on synthetic solidol and Litol-24 form the columnar mesophases depending on thermodynamical conditions and concentration of additives.Methods. We study the lubricant compositions with dielectric spectroscopy and и polarization light microscopy. The studies lubricant compositions are tested on the frictional machines by preceding authors, which performed their synthesis and numerical estimations for their geometry parameters. It is shown, that the columnar mesophase formed by the compositions with copper(II) carboxylates simulates favourable tribological conditions for lubrication (reduction of the friction coefficient at the appointed range of additive concentrations and reduction of wear) and unlike to crystalline phases, shows orientation effects at the surface of interacting surfaces of machine elements and devices. These factsmotivate the study of influence of physicochemical properties and composition on mesomorphism of considered lubricant compositions.Results. In our measurements, we found the main dielectric characteristics of two kinds of the lubricant compositions: dielectric constant and dielectric loss, electroconductivity, dissipation factor, the Arrhenius functions are plotted, and the activation energies of the lubricant compositions we study are calculated. The microphotogram for textures of the lubricant compositions depending on temperature and concentrations are received. The differences in mesomorphic properties of the lubricant compositions with additives Cu(II) valerate and isovalerate are confirmed.The conclusion of the work is that the composition of the lubricant is optimized by the choice of additive concentration, the length of the mesogenic chain of the copper(II) carboxylate molecule and its conformation.

Basing on the data of small-angle neutron scattering for the nanocomposite composed of fullerene C60 (16.5 wt. %) in the matrix of isotactic polypropylene, we received information on clusterization of nanoparticles and defined their geometric parameters and dimensionality. In this paper, we propose interpretation of particle aggregation possessing the properties of surface fractal in the size range up to 80 nm observed using small-angle neutron scattering method. Basing on the well-known theories of defect structures of a fullerene molecule C60 in non-Euclidean metrics, in particular, of disclinations and monopole in two-dimensional spherical Gödel space—time, we formulate a lattice version for the action of monopole gas, in which with the lattice Monte Carlo method, using abelian projection, we estimate the energy of monopole currents at different monopole concentrations. In frames of the proposed model, it is possible to calculate fractal properties of the fullerene C60 in a polymer composite and also to interpret evolution of disclinations.

Based on small angle neutron-scattering data from a nanocomposite composed of fullerene C60 (16.5 wt

We propose the theoretical description for the temperature and concentration phase transformations in composite lithium grease doped with the mesogenic additives of the copper(II) carboxylates family, copper(II) valerate and isovalerate, in the concentration range 1, 5, 10, 20 wt. percents. The changes in character of specific electric conductivity of these composites manifested in experiments on dielectric spectroscopy in the measuring electric field of the frequencies 100 Hz - 1 MHz and polarization microscopy, are reliable caused by reversible phase transitions from the discotic phase to isotropic one or at heating from room temperature to 391 K. We study correlations between defect structure and electrical properties of these composites using the model of the BKT transition. This transformation from the discotic to isotropic phase is associated with the evolution of topological defects dislocations induced by the mesogenic additives. The screw, transverse edge and longitudinal dislocations are realized in this case. We apply the numerical Monte Carlo technique to define their critical properties in the BKT transition.

Conducting polymers have wide technological applications in sensors, actuators, electric and optical devices, solar cells etc. To improve their operational performance, mechanical, thermal, electrical and optical properties, such polymers are doped with carbon allotrope nanofillers. Functionality of the novel nanocomposite polymers may be stipulated by size characteristics of nanoparticles and the polymer, different physical effects like charge transfer in such objects etc. We characterize and analyze structure, elastic, electric properties and of novel polymer nanocomposites, isotactic polypropylene (iPP) with high crystallinity, doped with graphene nanoplates (GNP) and nanographite particles at different concentrations and sizes about 100 nm, basing on the results of dynamic mechanical analysis (DMA), dielectric spectroscopy, small-angle neutron scattering (SANS) and theoretical modeling. Carbon NPs aggregated in fractal objects in the bulk of iPP change its mechanical plastic, elastic and electric properties comparing with pristine polymer. We study modification of nanofiller morphology with the concept of Cosserat elasticity which involves description of the behavior of linear topological defects caused aggregation of nanographite and GNPs. We supply our experimental data with numerical simulations on the lattice in frames of the model of Cosserat elasticity to estimate some mechanical characteristics of the whole composite iPP.

Data on the morphology of carbon allotrope nanoparticles in an isotactic polypropylene (IPP) matrix are analyzed. They are obtained using the small-angle neutron scattering method and a YuMO spectrometer at the IBR2 reactor of the Frank Laboratory for Neutron Physics, Joint Institute for Nuclear Physics (Dubna, Russian Federation). The fractal dimensionality is calculated, the form is reconstructed, and the geometric dimensions of the obtained particles and aggregates of single-wall carbon nanotubes (SWCNTs) in the IPP volume taken in concentrations of 1.2, 2.6, and 8 wt % are determined using ATSAS software. It is established that nanotubes form fractal nanoobjects with a rough surface in the IPP volume. Composite IPP/SWCNT systems are polydisperse to a significant degree; nanotubes twist into coils and knots and become more densely packed; in the polymer volume, the dimensions of the formed nanoparticles and their aggregates are several times larger than the initial ones used during synthesis. A model of knot formation in polymer materials based on calculating the asymptotic Hopf invariant and the lattice fractal dimensionality is used in this paper to interpret the results and predictions of the possible morphology forming in samples of such a type. The energies and probabilities of knot formation are estimated qualitatively using the Monte Carlo method.

We study the aggregation of carbon allotrope nanofillers in the matrix of isotactic polypropylene with direct small-angle neutron scattering measurements. With the ATSAS software, we analyzed the data and determined the fractal shape, dimension, and sizes of nanofiller aggregation in the bulk of isotactic polypropylene over the range of the scattering angles. We estimated the volume distributions and aggregation of different types of carbon nanofillers at different concentrations: nanographite, graphene nanoplatelets (GNP), fullerenes, single-walled carbon nanotubes (SWCNT), multi-walled carbon nanotubes (MWCNT) and binary fillers MWCNT/GNP. We reconstructed the shape of nanoscale particles and aggregates of a few nanofillers SWCNT, MWCNT and MWCNT/GNP and found that the systems are polydisperse; nanofillers associate in the volume of isotactic polypropylene as fractal dense aggregates with rugged surface, their sizes exceeding original dimensions of nanofillers several times.

The possibility of determining the kinetic parameters of a reaction proceeding in a reactor with a fixed catalyst bed under critical conditions of ignition is demonstrated. The device of the measuring reactor and the consequences of ignition are described in detail. The proposed approach can be applied to corresponding variants of Fischer–Tropsch synthesis for hydrocarbons, along with other types of synthesis that employ fixed catalyst beds and high energies of activation. It is an easy way of determining the activity of catalysts.

We provide numerical Monte Carlo modeling of conductive properties of polymer composites, comprised by doping a polymer matrix with carbon nanotubes and III-IV GaAs nanowires. We apply the basic Su-Schrieffer-Heeger model, which is considered universal for every component of such ternary systems, and in a general case with required parameters. Such modeling of conductive characteristics is motivated by requirements of optimization of geometry and structure of novel photovoltaic devices.

1Институт теоретической и экспериментальной физики им. А. И. Алиханова НИЦ «Курчатовский институт», ул. Большая Черемушкинская, 25, 117218 Москва, Россия. E-mail: elnikova@itep.ru 2Институт синтетических полимерных материалов им. Н. С. Ениколопова РАН, ул. Профсоюзная, 70, 117393 Москва, Россия. E-mail: Anapon@ispm.ru, Shev@ispm.ru 3Ивановская государственная сельскохозяйственная академия ул. Советская, 45, 153012 Иваново, Россия. Е-mail: vladim-terent@yandex.ru 4Ивановский государственный университет, ул. Ермака, 39, 153025 Иваново, Россия. Е-mail: ob_akopova@mail.ru

In order to improve the wear resistance of machine parts in industry and agriculture, the various synthetic lubricants with mesogenic additives are used. It is established that adding an additive to the base lubricant leads to a decrease in the friction coefficient and a decrease in the wear of the machine parts. Such multi-component systems, lubricants and additives, are lyotropic liquid crystals (LC) and exhibit rich mesomorphism which also affects their tribological characteristics. The composing of phase diagrams of LC lubricants with additives depending on the concentration and thermodynamic quantities is an important research task in connection with the need to optimize the composition of lubricants and to determine the regimes of their most effective employment. In this regard, in addition to mechanical testing of specimens in the presence of lubricant compositions, it is necessary to study the physicochemical properties and carry out structural studies of multicomponent lubricants. We were motivated by the possibility to complement the existing data on the optical and X-ray spectroscopy, electron microscopy and theoretical studies of the thermodynamic parameters of lubricant composites by dielectric spectroscopy (DE). Using the method of DE spectroscopy, we first investigated the electrical properties of lubricating compositions based on Litol's-24 comprising mesogenic additives as homologues carboxylates of copper (II), valerate and isovalerate copper in the concentration range 1, 5, 10 and 20 wt. %. We found the frequency dependence of the dielectric permeability, conductance, dielectric loss, as well as the temperature and concentration dependence of the electrical quantities of lubricant compositions in the measuring electric field of the frequency range 100 Hz – 1 MHz and at heating from room temperature to temperatures exceeding Litol's-24 melting temperature. The paper confirms the possibility of the occurrence of phase transitions between the columnar and isotropic liquid-crystalline phases at the concentrations of additives of 1, 5 and 10 wt. %, and estimates the activation energies of the lubricant compositions in order of magnitude. The obtained results are applicable for the analysis of tribological characteristics of lubricant compositions.

The paper studies of kinetics of epoxy resin curing by dielectric analysis method. Kinetic parameters largely depend on the measurement mode. During curing, time dependence tgδ passes two maximum loss, the first of which occurs only in the case of measurement at low frequencies. The position of both maxima is largely determined by frequency at which the measurements are performed. The latter circumstance is very important, due to the fact that the time of occurrence of the maximum is usually associated with gelation of the system, the first maximum determines the transition from viscous state to viscoelastic one, and corresponds to the onset of gelation process. In connection with these methods the possibility of using them in additive technologies is discussed.

The paper deals with the methods of controlling processes and crosslinking curing reactions in resins and other polymers by measuring their dielectric properties. The methods of hardware design and the means of measuring conductivity and dielectric losses are presented.

Во второй части статьи обсуждается пространственное перераспределение ионов в электрическом поле и его следствия для ионной полимеризации.

Reaction mixtures in which polymerization processes proceed are investigated both in an electric field and under classical conditions. The observed kinetic effects are explained using a model concept of the primary contribution to the revealed field effects from the dissociation of ion pairs due to the spatial redistribution of ions. This model may be applied to both cationic and anionic polymerization processes.

The first part of this paper considers the physical methods of research of polymers and copolymers, the impact of the electric, magnetic and electromagnetic fields on their properties and characteristics, and new physical effects in the dynamics of chemical reactions. At the present time, these areas are developing successfully, including through research on additive technologies.