Том 65, № 2 (2023)

The publications of domestic and foreign researchers devoted to studies of Ziegler–Natta catalytic systems based on neodymium, vanadium, and titanium modified with organochlorine compounds and used in the synthesis of polyolefins and polydienes are scrutinized. The relevant patent literature has been explored, and the main development trends in the field of metal complex catalysis using organochlorine compounds have been analyzed. The advantages and disadvantages of such catalytic systems are considered in comparison with classical unmodified catalysts, in which alkylaluminum chlorides are used as a source of chlorine. The authors analyzed in detail published data on the role of the chlorine atom as a ligand in active sites for the polymerization of olefins and dienes. The role of mono- and polychlorinated organic compounds in neodymium, vanadium, and titanium–magnesium catalytic systems has been revealed and described

Polybenzoxazine based on 3-phenyl-2,4-dihydro-1,3-benzoxazine is studied by X-ray photoelectron spectroscopy. It is shown that during polymerization, along with oxazine ring opening, formation of methylol and other functional groups involved in three-dimensional structure development occurs.

The radical copolymerization of sodium styrene sulfonate with vinyl saccharide 2-deoxy-2-methacrylamido-D-glucose in water is studied. For sodium styrene sulfonate and 2-deoxy-2-methacrylamido-D-glucose the reactivity ratios are found to be r1 = 1.58 ± 0.05 and r2 = 0.18 ± 0.01, respectively. Water-soluble copolymers of varying compositions and molecular weights demonstrating high antiviral activity are synthesized.

Kinetics of the production of nanofibrils from chitin of different origin in the reaction of acid hydrolysis has been studied. The features of splitting of the microparticles to the nanoscale (into nanofibrils) have been investigated by means of scanning electron microscopy and the difference in the geometric size of the nanofibrils has been revealed.

Cadmium sulfide nanosized particles doped with Eu3+ ions are synthesized by colloidal synthesis in polymerizing methyl methacrylate. Highly transparent glassy CdS- and Eu3+-containing composites, which exhibit the broadband luminescence of CdS and the narrowband luminescence of Eu3+ ions, are obtained by the bulk radical polymerization of methyl methacrylate. These composites are intended for use as luminescent elements of various electronic devices, optical sensors, lenses, and prisms. The glass transition temperature and the degradation temperature of the composites are determined. The spectral regions of absorption and photoluminescence excitation are ascertained. It is shown that semiconductor modifiers affect the thermal and spectral-luminescent properties of poly(methyl methacrylate) and corresponding composites.

For butadiene polymerization with the multicenter catalyst TiCl4–Al(i-C4H9)3 the inverse kinetic task with identification of the kinetic scheme and determination of the kinetic parameters is solved. The preliminary experimental molecular weight distribution of polybutadiene macromolecules is approximated by the superposition of Flory distributions. Polymerization is modeled by the Monte Carlo method using a novel fast “inversion” algorithm that enables the time of calculations to be reduced by two orders of magnitude compared with the classical scheme of the method. It is shown that for identification of the kinetic scheme of diene polymerization in the presence of multicenter catalysts coincidence between the experimental and calculated dependences of monomer conversion on time and the dependences of average weights (or average degrees of polymerization) on polymerization time is insufficient. Coincidence between molecular weight distributions at all polymerization times is also required