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The conformations of molecules in a diene (butadiene, isoprene) complex with hydrogen peroxide and isopropyl alcohol, for which local energy minima are identified, and a mechanism of hydrogen peroxide decomposition have been studied by the quantum-chemical density functional theory method. It has been shown that depending on the initial multiplicity of the system, the decomposition can result in the formation of different intermediate and final products, which indicates the probability of singlet to triplet conversion of hydrogen peroxide in the real system. [ABSTRACT FROM AUTHOR]

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The hydroxyl groups in ORD oligomers obtained by radical polymerization in alcohols under the action of hydrogen peroxide have been studied by Fourier IR-spectroscopy method. The acetylation reaction was used to identify the hydroxyl groups. It was found that the spectra of hydroxyl groups of oligomers obtained in various alcohols are close excluding stretching vibrations O-H in the field of 3000-3500 cm-1. In this field, a form and frequencies of bands differ as a result of a different association of hydroxyl groups in bulk. Associates do not destroy even at extreme dilutions both inert and active solvents. Microstructure of oligomers is typical for rubbers of radical polymerization and do not depend of an alcohol nature. [ABSTRACT FROM AUTHOR]

The urethane formation between phenylisocyanate and hydroxyl-containing oligoisoprenes ORD obtained by radical polymerization in the butyl alcohol solutions under the action of hydrogen peroxide has been studied by Fourier transformation IR-spectroscopy. The rate constants were determined and the possible causes of various reactivity of hydroxyl groups have been discussed. [ABSTRACT FROM AUTHOR]

Analytical and graphic dependences are presented for determining the fraction of molecules of oligomers of different functionality and the number-average functionality of oligomers obtained in mixtures of initiators of different functionality. The dependences can be used for practical calculations associated with the production of oligomers with specified functionality and functionality distribution of the molecules. [ABSTRACT FROM AUTHOR]

The urethane formation reaction between phenylisocyanate and hydroxyl-containing oligoisoprenes obtained by radical polymerization in the C1-C3 alcohol solutions initiated with hydrogen peroxide has been studied by Fourier transformation IR-spectroscopy. A stepwise change of the reaction rate was discovered during its course, which was explained by structural changing in the oligomer matrix. [ABSTRACT FROM AUTHOR]

An initial rate of the isoprene polymerization under the influence of the hydrogen peroxide depends on the properties of solvents. First of all, the electrophylic solvation of the hydrogen peroxide has an influence on the studied process; the non-specific interaction into a system has a lesser impact. [ABSTRACT FROM AUTHOR]

The orders by monomer and initiator in the reactions of radical polymerization of isoprene initiated with benzoyl peroxide and hydroperoxide of isopropylbenzene in the solution of isopropyl alcohol as well as with hydrogen peroxide in acetone and cyclohexanone. The values of the orders has been analyzed from the positions of chemical and intermolecular interactions between polymerization system components. [ABSTRACT FROM AUTHOR]

Regularities and features of the reaction aminolysis of copolymers of ethylene with vinyl acetate with various concentrations of vinyl acetate units were installed. It is shown that the reaction of aminolysis of the conversion of acetate groups in EVA copolymers with increasing content decreases and the content of hydroxyl groups and the number of substituted hydroxy acetate units increases, it is revealed that the grafting of hydroxyl groups in vinyl acetate links on the surface of granules of the copolymer contributes to improving their physical mechanical characteristics. [ABSTRACT FROM AUTHOR]

Kinetic acetylation of hydroxyl groups of oligodienes obtained with various methods have been conducted to differentiate their reactivity. The contents of hydroxyl group with divers reactivities and the acetylation rate constants have been determined. [ABSTRACT FROM AUTHOR]

The azoinitiator of radical polymerization - 2,2'-azo-bis-2-methylpropionamide is synthesized with the use of peroxide hydrogen and an 2,2'-azo-bis-2-methylpropiononitrile [ABSTRACT FROM AUTHOR]

Modification of isoprene and acrylonitrile cooligomers has been conducned in week alkaline medium. The cooligomers were synthesized with epoxide group contents to 13,5 % . They were tested as the modifiers at rubber-plastics preparing. [ABSTRACT FROM AUTHOR]

The work is devoted to the study of self-organization processes in disperse systems. The most relevant aspect of such self-organization is the relationship between structure and properties in polymer composites. In this paper, we are talking about dispersion media (matrices), namely, the mechanisms of phenomena and interactions that occur during the deformation of disperse systems. These interactions depend on the properties and processes of self-organization of dispersion media and determine the properties of future polymer composites. One of the most popular dispersion media are diene oligomers (liquid rubbers). In this work, the rheology of diene oligomers with terminal hydroxyl groups (HRD) was studied in a wide range of shear rates and temperatures. It was assumed that in the case of oligoisoprene, an increase in the activation energy of viscous flow (from 46 to 95 kJ/mol) with decreasing temperature is associated with an increase in the density of the fluctuation dynamic structure with an increase in the volume content of associates of polar OH groups (i.e., nonionic micelles) with a decrease in thermal energy kT (k is the Boltzmann constant). The results of rheological studies for the first time (for nonionic liquids) were presented within the framework of the Angell's concept, from which it followed that these systems are fragile, i.e. they are very promising in terms of studying structure formation in a shear field. [ABSTRACT FROM AUTHOR]

The graft block copolymer (GBC), based on the functionalized ethylene-vinyl acetate copolymer and monoisocyanateurethane of reactive olygomers of soybean oil, was synthesized. The structure of the copolymer was confirmed by IR-spectroscopy and gel permeation chromatography. Physico-chemical characteristics of the GBC were studied by thermal gravimetric analysis and differential scanning calorimetry. It was found that the obtained GBC has high heat resistance, the glass transition temperature of the copolymer is shifted towards lower temperatures. Efficient use of GBC as compatibilizer for composite materials based on recycled polypropylene and crumb rubber was shown. [ABSTRACT FROM AUTHOR]

Graft block copolymer (GBC) based on functionalized ethylene-vinyl acetate copolymer and macrodiisocyanate based on liquid rubber was synthesized, the structure of GBC was confirmed by IR-spectroscopy. Physico-chemical characteristics of the GBC were investigated by thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC). It was found that the GBC has a higher thermal stability compared with the original components, and the glass transition temperature is shifted to lower temperatures. Efficient use of PBS as compatibilizer for composite materials based on recycled polypropylene and crumb rubber was shown. [ABSTRACT FROM AUTHOR]

The methods of synthesis of monomers and oligomers containing 5-membered cyclocarbonate group have been investigated. Particular attention is paid to the technologically attractive way of obtaining cyclocarbonate by the reaction of epoxy compounds with carbon dioxide. In recent years, many studies focus on the reaction of carbonation epoxidized vegetable oils, which allows obtaining biomaterials that can be an alternative to polymeric materials based on petroleum feedstock. Synthesis of cyclic carbonates is regarded as one of the most important ways to reduce global CO2 emissions, and industrial search for ways to use it. [ABSTRACT FROM AUTHOR]

Structural studies of original and functionalized copolymers of ethylene and vinyl acetate and compositions based on them containing crumb rubber by IR-spectroscopy, X-ray analysis and DSC were carried out. It was shown that vinyl acetate content affects on structuring of the copolymers and their physical and chemical properties. Filling the copolymer rubber crumb did not significantly affect on structuring of polymer matrix and leads to a decrease in mechanical properties. [ABSTRACT FROM AUTHOR]

Synthesis methods of reactionary of derivative vegetable oils and their use for modification and development of composite polymeric materials are considered. Application of the received materials are defined. [ABSTRACT FROM AUTHOR]

The synthesis of oligomeric azoinitiator on the base of diazoaminobenzene and threeisocyanate of castor oil was developed. The synthesis and properties of block-copolymers obtained on the base of oligomeric polyazoinitiators by termoinitiated radical polymerization with the use of the synthesized oligomeric azoinitiator and a monomer of styrene or monomers of pyrolysis fraction C9 of petroleum products was investigated. Kinetic peculiarities of processes of synthesis by differential calorimetry have been investigated. The structure of synthesized block-copolymers were confirmed by the FTIR-spectroscopy. The molecular weight distribution and viscosity of the BCPs were determined. [ABSTRACT FROM AUTHOR]

For the first time an influence of small additives of a modificator RU-1 on property of secondary polythene and its composites with a rubber crumb is investigated. Their structural features with the help of methods of FTIR-spectroscopy, X-REY analysis are investigated. Physicomechanical properties, character changes an index of fluidity of compositions, changes of the contents of gel-fraction at presence RU-1 are investigated. [ABSTRACT FROM AUTHOR]

Kinetics and chemistry process of polydiene sulfuric vulcanization in the presence of quaternary ammonium salts (QAS), synthesized from accessible domestic raw material have been investigated. It was established, that QAS is not only the accelerator of vulcanization of low activity, but also can be used as the multifunctional additive in the absence in a mixture of the vulcanization activator. Unlike traditional accelerators of vulcanization, QAS, possibly, does not interact directly with rubber and does not crosslinked it. Nevertheless, QAS easily reacted with sulfur, that is an initial act of adduct formation - the polysulphidic agent of vulcanization that react with rubber with formation of active addition products, and in the further of vulcanization network. [ABSTRACT FROM AUTHOR]

An urethane formation reaction between phenylisocyanate and hydroxyl-containing oligodiene prepared by radical polymerization in isopropyl alcohol solution in the presence of hydrogen peroxide has been studied by FTIR spectroscopy. The graded increase in the reaction rate constant during a reaction course has been stated. It was accounted for by the reaction product catalysis and the structural changes in the area of a reaction course. [ABSTRACT FROM AUTHOR]

Kinetic acetylation of hydroxyl groups in oligobutadienes obtained by modification with mercaptoethanol and hydrogen peroxide. Contents of the hydroxyl groups with a different reactivities and rate constants of acetylation of hydroxyl groups were determined. [ABSTRACT FROM AUTHOR]

The regularities of the creation rubber-plastics on the base of the secondary polyethylene of low density, primary polyethylene, dispersed rubber crumb and modifiers based on liquid rubber with functional groups have been investigated. Their structure and physico-mechanical characteristics have been studied. [ABSTRACT FROM AUTHOR]

Influence of process of updating of a rubber crumb by urea hydrogen peroxide on properties of rubber plastic is studied, shown that the inoculation of hydroxyl groups on a crumb surface promotes improvement of physicomechanical characteristics and decrease in degree of swelling of composites. [ABSTRACT FROM AUTHOR]

Influence of additives peroxyds dicumyl and benzoyl, and chemical - active connections urotropin and a product of interaction resorcinol (1,3-benzenediol) with urotropin (RU-1) on properties of compositions is investigated on the basis of secondary polythene. The method of FTIR -spectroscopy, DSC, by measurement of the contents of gel - fraction, a parameter of fluidity of compositions , carries out researches of their structural features, thermal, physical and mechanical properties, etc. [ABSTRACT FROM AUTHOR]