Influence of Polymer Nature on Electroadhesion.

Electroadhesive systems are promising for creating delicate robotic manipulators operating both in the natural environment and in space conditions. Using thermosetting epoxy resin, polyurethane and polyester resin as examples, the influence of the polymers' natures, potential differences and current strengths on electroadhesive interactions in polymer-polymer systems was studied. The investigations were carried out by recording the force of normal separation of substrates from electroadhesives using contact and contactless methods at various electrical parameters of the systems and their components.

Regulation of the Phase Structure in the Crystallizing Curing System PCL-DGEBA.

Qualitative and quantitative aspects of the formation of various types of phase structures, sizes and compositions were considered. For the studied polycaprolactone-epoxy resin/4,4'-diaminediphenylsulfone system, a phase diagram characterized by amorphous separation with a lower critical solution temperature was constructed and its evolution was traced with increasing conversion degree of epoxy groups. A method is proposed for determining the temperature-concentration parameters that determine the type of phase structure of composite materials, based on the optical interferometry method.

Phase Equilibria and Interdiffusion in the Ternary System Epoxy Oligomer-Polysulfone-Alkyl Glycidyl Ether.

Phase equilibria, interdiffusion and structure in the initial uncured mixtures of epoxy oligomer-polysulfone-alkyl glycidyl ether were studied. Binodal curves were constructed on isothermal sections of the ternary phase diagram. Thermodynamic mixing parameters were calculated and spinodal curves were plotted.

Density Fluctuations Inside an Individual Polymer Coil.

More than five hundred images of individual macromolecules of random styrene-butadiene copolymers and styrene-isoprene block copolymers dissolved in a polystyrene matrix were analyzed. The presence of density fluctuations inside the macromolecular coil has been established. Within the framework of the model of harmonic oscillations, the radial distribution of such density fluctuations is estimated.

Methods of Formation of Protective Inhibited Polymer Films on Tungsten.

A comparative study of anticorrosive inhibited polymer films on the tungsten surface formed from an aqueous solution of inhibited formulations (INFOR) containing organosilane and corrosion inhibitors was carried out by means of the prolonged exposure of a tungsten product in a modifying solution and by the method of cataphoretic deposition (CPD). Depending on the method of forming films on tungsten, the molecular organization of the near-surface layers was studied (ATR-FTIR), and the subprimary structure of the films was explored (TEM). The optimal modes of cataphoresis deposition (CPD duration and current density applied to the sample) for the formation of a protective inhibited polymer film on the tungsten surface were established by means of SEM.

Effect of Molecular Weight on Phase Equilibrium in the Polystyrene-Poly(methyl methacrylate) System.

Data on the solubility of oligomer polystyrene (PS) and poly(methyl methacrylate) (PMMA) of various molecular weights have been obtained. The binodal and spinodal curves of the phase state diagram with the upper critical solution temperature (UCST) are constructed through simulation within the framework of the Flory-Huggins theory. The influence of the molecular weight of polymers on the contribution to their mixing has been compared, and correlation curves have been plotted.

Epoxyorganosilane Finishing Compositions for Fibrous Fillers of Thermosetting and Thermoplastic Binders.

The development of universal finishing compositions for fibers of various natures is an urgent task for polymer composite materials science. The developed finishes can be used for the fiber reinforcement of polymer matrices with a wide range of surface free energy characteristics. Epoxy systems modified with diaminesilane in a wide concentration range were examined by optical interferometry, FTIR spectroscopy, DSC and the sessile drop technique.

Phase Equilibrium and Interdiffusion in Blends of Polystyrene with Polyacrylates.

The solubility and interdiffusion of polystyrene (PS) with polymethyl acrylate (PMA), polyethyl acrylate (PEA), polybutyl acrylate (PBA), and polyethylhexyl acrylate (PEHA) have been studied by the optical interferometry method. Phase state diagrams are plotted. It is shown that they are characterized by the upper critical solution temperatures (UCST), which are localized in the temperature range above 450 K.

Phase Equilibrium and Interdiffusion in Poly(Vinyl Methyl Ether)-Water System.

The phase state diagram of the poly(vinyl methyl ether)-water system in a wide concentration range was obtained by the optical interferometry method. It was shown that this system was characterized by a complicated phase equilibrium with two lower critical solution temperatures, one of which was located in the concentrated region at 21 °C, and the other one in the region of a dilute solution at 31 °C. In the framework of the Flory-Huggins theory, pair interaction parameters were calculated for different parts of the binodal curves, and an attempt was made to reverse simulate the diagram in different conditions.