Methods for dispersing of the thermally expanded graphite (TEG) in a dilute alcohol medium and for modifying the surface of a TEG with an ultradisperse dielectric - silicon dioxide (SiO2) are proposed. The new polymer nanocomposites (PNC) obtained based on polychlortrifluoroethylene (PCTFE) with a low content of dispersed TEG and a modified filler TEG/SiO2 are characterized by high rates of electrophysical properties. Using electron microscopy and X-ray photoelectron spectroscopy, the features of the electronic structure of the surface of composites are investigated. Using the two-contact method in the kilohertz frequency range, the features of change in the electrophysical properties of composites depending on the content of fillers and temperature have been established. Based on research and comparative analysis of thermophysical properties (specific heat capacity cp, temperature coefficient of linear expansion α) of the systems, the influence of the structural-morphological state of the components and their concentration, the level of interfacial interaction on the physical properties of nanocomposites was investigated. The fact of the appearance of interfacial polarization in the PCTFE-TEG/SiO2 interfacial layers due to the appearance of the TEG/SiO2 and PCTFE-SiO2 interphase layers is established, which, while preserving the complex of properties inherent to the polymer materials, increases the overall electrical conductivity of the composites. It was also established that the modified nanofiller exhibits greater activity in relation to the polymer matrix than the unmodified one. It is shown that the composites exhibit a dual effect of the modified nanofiller on the matrix structure, which manifests in the formation of a powerful crystalline structure in the zones of influence of the nanofiller and amorphization of the polymer matrix in the peripheral zones. It was found that the result of amorphization of the matrix is a decrease in the area of the peaks of temperature reflexes on the temperature dependences of the specific heat capacity and an increase in the absolute value of the temperature coefficient of linear expansion with an increase in the concentration of modified TEG.

A method of synthesis of acrylate-vinyl copolymers based on glycidyl methacrylate and styrene at different molar ratios and epoxy cyclocarbonates based on them was developed. Synthesis of styrene-glycidyl methacrylate (СP GMA/St) copolymers was carried out by the method of thermally initiated radical polymerization in steel reactors in the presence of 1% azo-bis-isobutyronitrile initiator at a temperature of 65 °C for 10 hours. The number of epoxy groups in the synthesized СP GMA/St, determined by the potentiometric titration method, naturally decreases with a decrease in the molar ratio of GMA/styrene. The synthesis of СP GMA/St epoxycyclocarbonates was carried out in a high-pressure autoclave by passing CO2 through the reaction mixture of a solution of KP in toluene with a catalyst (tetrabutylammonium bromide 5%) with stirring at a temperature of 110–120 °C, a pressure of (4-5) atm. The structure of СP and ECC was confirmed by IR spectroscopy. No bands of double bonds are observed in the IR spectra of СP GMA/St, there are vibration bands characteristic of oligostyrene and vibration bands of C=O, C–O–C and epoxy groups. During the formation of ECC, new vibration bands of cyclocarbonate groups with a maximum of 1802 cm-1 appear, changes are observed in the absorption region of C–O–C groups (1100–1300) cm-1, and the vibration bands of epoxy groups with a maximum of 843 cm-1 decrease. The study of relaxation transitions in acrylate-vinyl copolymers GMA/St and epoxy cyclocarbonates based on them using the DSC method showed that all samples are amorphous single-phase polymers. After changing the background, the excessive enthalpy observed during the first heating disappears, and the glass transition temperature shifts towards higher temperatures, which indicates the formation of a denser and thermodynamically balanced structure. The thermostability of the synthesized GMA/St copolymers and epoxy cyclocarbons was investigated by the method of thermogravimetry. It was established that all the obtained substances have one stage of weight loss and are heat resistant, since weight loss begins at a temperature above 240 °C. In the future, the obtained epoxycyclocarbonates will be used for the synthesis of polyurethanes by the non-isocyanate method.

Modified catechol chitosan was synthesized to examine the intricate connections between Fe(III) and catechol under different pH conditions. The conjugation of the catechol moieties, which determines the structure of the hydrogel, was evaluated by nuclear magnetic resonance spectroscopy and ultraviolet-visible spectroscopy. The gel formation was well maintained by the dual cross-linking networks of the electrostatic interactions between catechol chitosan solution (CCS) and Fe 3+ along with the covalent catechol-coupling-based coordinate bonds. Three pH conditions of 3, 5, and 7 were applied for ethylenediamine tetra-acetic acid (EDTA) treatment as a triggering factor in modifying the uniform hydrogel structure. The hydrogels demonstrated enhanced mechanical strength and cohesiveness at a pH of 5, and rheology analysis was used to determine the storage and loss moduli. Several analysis and characterization techniques were utilized to describe the crosslinking components and confirm the physical properties of the chitosan backbone polymer chain in the modified ironinduced hydrogel frameworks before and after EDTA treatment.

Graft polymers are gaining increasing interest because of their unique architectural characteristics. We recently reported a novel type of depolymerizable graft polymer based on poly(trans-cyclobutane fused cyclooctene), in an effort to address the trade-off between depolymerizability and controlled grafting-through polymerization. In this work, we examine the thermal, mechanical, and morphological properties of a graft copolymer thermoplastic material prepared by copolymerizing poly(Llactide) and margaric acid-based macromonomers. A copolymerization kinetics study reveals that the two macromonomers are incorporated almost randomly and that the domain spacing measured from small-angle X-ray scattering is consistent with the random distribution. An investigation of the crystallization behavior suggests that proper thermal treatment is required to maximize, or to even observe crystallinity. The physical states of the soft and hard domains, whether melt, glassy, or semicrystalline, significantly impact the tensile properties of the resulting copolymer materials. Finally, the rheological properties and morphological features are discussed.

Iris-patterned lenses have recently become popular in the field of soft contact lenses (SCLs), and SCLs are typical examples of an industrial application of gel materials. As these patterns can be printed using oxidized-metal-containing pigments, the oxidized metals may be exposed on the lens surface depending on the printing method, potentially accounting for various health hazards. To evaluate the state of the exposed oxidized metal on the lens surface, we analyzed the colored layer, mainly consisting of pigments, on the lens surface via multiple probing methods, such as transmission electron microscopy (TEM), scanning TEM with energy-dispersive X-ray spectroscopy, hard X-ray photoelectron spectroscopy, and X-ray absorption fine structure (XAFS). Furthermore, we confirmed that the XAFS conversion electron yield (CEY) and fluorescence yield (FY) methods demonstrated high sensitivity toward revealing the existence of pigments. Thus, the use of a combination of XAFS CEY and FY methods can facilitate the effective distribution analysis of various elements in the interior of materials such as cosmetic CLs.