The disperse composition of trans-1,4-polyisoprene granules and supported titatium–magnesium catalyst particles in the ultrarapid polymerization of isoprene within 0.1–0.7 s is studied. It is shown that within this period the alteration of external and internal fragmentations occurs between two fractions of polymer granules that are formed by 0.1 s of polymerization and already contain significantly fragmented catalyst particles. The correlation between these processes and molecular mass characteristics of trans-1,4-polyisoprene is investigated. It is found that the external fragmentation is accompanied by a decrease in the average molecular masses of the polymer, while the internal fragmentation leads to formation of a higher molecular mass trans-1,4-polyisoprene. As a result, the fraction of polymer granules with a diameter of 7.5 μm is formed by 0.7 s of polymerization and replication to high conversions is developed on their basis.

The short-time polymerization of butadiene induced by heterogeneous titanium catalysts was studied for the first time. In the 0.1−0.3 s time interval, polymerization is characterized by a considerable decrease in the chain propagation rate constant and 1,4-stereospecificity of the catalysts. A structure kinetic continuum model was proposed in which the initiation step and the first propagation steps are kinetically continuous. The violation of this continuity changes the catalyst stereospecificity and creates conditions for chain transfer reactions.

Short-time polymerization of isoprene under the action of supported titanium–magnesium catalyst is carried out. The pulsation mixing of the reagent flows and the unit design features allow one to reduce the average residence time of reagents in the reaction zone and to study the first 0.7 s of the isoprene polymerization. It is found that, very early in polymerization, the propagation of polyisoprene macromolecules proceeds on the surface of the primary aggregates of catalyst particles characteristic of a high trans-1,4 specificity via the “living” mechanism with a high rate. Furthermore, the fragmentation of the initial aggregates of the catalyst particles occurs, which results in formation of new polymerization centers, a decrease in the average molecular masses of polyisoprene, and a broadening of the polymer MMD. The results are explained by the existence of a range of the kinetic continuity of the rapid initiation stage and several subsequent stages of macromolecule propagation, followed by a significant decrease in the chain propagation rate constant compared to the initiation constant.

Впервые исследована кратковременная полимеризации бутадиена под действием гетерогенных титановых катализаторов. Установлено, что в интервале 0,1-0,3 с полимеризация протекает в условиях значительного снижения константы скорости реакции роста полимерной цепи и 1,4-стереоспецифичности катализаторов. Предложена модель структурно-кинетического континуума, согласно которой стадия инициирования и самые первые акты роста являются кинетически непрерывными. Нарушение этой непрерывности приводит к изменению стереоспецифичности катализатора и создаёт условия для протекания реакций передачи цепи.

The short-time polymerization of isoprene under the action of a TiCl 4 / MgCl2−i -Bu 3 Al heterogeneous catalyst has been investigated. Pulse mixing of the catalyst and monomer in a cylindrical tubular reactor with a certain length followed by ethanol injection has made it possible to carry out polymerization for 0.1−0.7 s. In the first 0.3 s, when there is a considerable rise in the activity of the catalyst, living polymerization of isoprene takes place. In this period, polyisoprene has up to 95% trans -1,4 units. Extending the polymerization time to 0.7 s diminishes the average molar mass of polyisoprene, broadens its molar mass distribution, and decreases the concentration of trans -1,4 units to 83%. The data of this study have been analyzed on the basis of the kinetic continuity of the polymer chain initiation and growth.

The polyheteroarylenes of new type, called polyarylenediphthalides (PADPs), containing two adjacent phthalide groups regularly alternating with aromatic (heteroaromatic) fragments in the main chain have been developed. For obtaining PADPs, two approaches based on the dehalogenation reactions were used. In the first, polycondensation of the pseudo-acids chlorides was carried out that led to the polymers with random stereo configuration of diphthalide groups. In the second, stereospecific PADPs were formed using diastereoisomeric pure halogenated biaryl-3,3′-diphthalides (meso and racemic) as monomers that attach themselves to the growing polymer chain entirely keeping their stereo configuration. The obtained polymers start to soften and decompose at ≈350°C in inert atmosphere. Degradation of PADPs at deep carbonizing stages in the inert atmosphere is followed by formation of foamed coke with increased content of diamond-like carbon that possesses a high hardness (≥8 by Mohs scale).

Atomic-force microscopy is used to study the supramolecular structure of submicron films of electroactive thermally stable polymer (polydiphenylenephthalide (PDP)). It has been demonstrated that PDP films produced using centrifuging are solid homogeneous films with thicknesses down to several nanometers, which correspond to two or three monomolecular layers. The film volume is structurized at thicknesses greater than 100 nm. The study of the rheological properties of solutions used for film production yields a crossover point that separates the domains of strongly diluted and semidiluted solutions. A transition from the globular structure to the associate structure is observed in films that are produced using solutions with a boundary concentration. A model of the formation of polymer film that involves the presence of associates in the original solution is discussed.

The ultrasonic irradiation of the reaction mixture during its formation in the polymerization of butadiene and isoprene with a microheterogeneous titanium catalytic system causes acceleration of the process. In this case, the multicenter titanium catalytic system is transformed into a quasi-single-center system and the type of operating center depends on the nature of a polymerizing diene. During the polymerization of butadiene, this effect leads to an increase in the amount of trans-1,4-units and to a decrease in the average molecular masses. In the case of isoprene, the resulting polymer contains a higher amount of cis-1,4-units.

The mechanism of methyl methacrylate polymerization in the presence of 1,3,5-trithiane was studied.

Ультразвуковое облучение реакционной смеси в момент ее формирования при полимеризации бутадиена и изопрена на микрогетерогенной титановой каталитической системе приводит к ускорению. При этом полицентровая титановая каталитическая система трансформируется в квазимоноцентровую, а тип функционирующих центров зависит от природы полимеризующегося диена. При полимеризации бутадиена это приводит к увеличению 1,4-транс-звеньев и снижению средних ММ. В случае изопрена образуется полимер с более высоким содержанием 1,4-цис-звеньев.

Corrosion resistance of tantalum, titanium, and a number of carbon materials in a NaOH melt in the atmosphere of argon was studied in the temperature range 400–700°C.

Solvent effect on the molecular characteristics of polybutadiene and on the kinetic heterogeneity of catalytic systems based on TiCl4 was studied.

Copolymerization of butadiene and isoprene on the titanium catalyst proceeds on three types of active sites, and this correspond to the standard set of homopolymerization of isoprene. Sites responsible for the preparation of low-molecular-mass fractions of macromolecules are more active in the copolymerization as compared with homopolymerization of butadiene and isoprene. Change in the hydrodynamic regime in the reaction region is accompanied by an increase in the copolymerization rate due to an increase in the over-all concentration of active sites but it does not affect the typical set of growth sites of macromolecules. Distribution curve of active sites with respect to their reactivity is shifted to the high-molecular-mass region with increasing average weight molecular mass with decreasing average number molecular mass when the corresponding molecular-mass distribution becomes broader.

Controlled radical polymerization of methyl methacrylate and styrene initiated by azobisisobutironitrile or benzoyl peroxide in the presence of a chlorine-containing complex of FeIII with 5,15-bis(4’-tert-butylphenyl)-2,8,12,18-tetra(n-butyl)-3,7,13,17-tetramethylporphyrin was investigated.

The effect of fullerene C60 on the composition of macromolecules in the free-radical copolymerization of styrene with diallyl isophthalate is estimated. It is shown that the maximum amount of C60 is contained in the high-molecular-mass fraction of the products. Constants in the Kuhn-Mark-Houwink equation are determined for the fullerene-containing copolymer synthesized from an equimolar mixture of monomers.

Benzoyl peroxide-, lauryl peroxide-, and AIBN-initiated free-radical polymerization of methyl methacrylate has been studied in bulk and solution in the presence of macrobicyclic iron(II) bis(ferrocenyl borate) tris(nioximate). It has been found that the ferrocenyl-containing iron(II) clathrochelate forms efficient initiating systems with peroxides, whereas, in the case of AIBN, its presence has no effect on the kinetic parameters of the process and the properties of the resulting polymer. The use of clathrochelate complex-peroxide initiator systems accelerates the polymerization of methyl methacrylate and decreases the molecular mass of the polymer. The kinetic parameters of the process have been determined.