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By the interaction of phenyl (benzyl) substituted cyclopropylcarbinols with epichlorohydrin, the glycidyloxymethyl substituted phenyl(benzyl)cyclopropanes, used as active diluents of epoxide resin ED-20, were synthesized. It found that the addition of the obtained epoxy compounds to the epoxide resin decreases the viscosity of the resin and increases the lifetime of the compositions. The high degree of curing (96-98%) indicates the participation of the synthesized epoxycyclopropanes in the cross-linking processes. Some physical-mechanical characteristics of compounds made with the participation of the synthesized epoxycyclopropanes were established. The improvement of strength and heat-physical parameters of cured compositions in comparison with compositions made without diluents was revealed. [ABSTRACT FROM AUTHOR]

Catalytic activities of synthetic mordenite (SiO2/Al2O3=18) catalysts modified with metal cations (Pd2+, Ni2+, Co2+, Nd3+) calcinated in different air stream conditions in the temperature range of 300-420°C, at v=3,1 hour-1, H2:CH=3:1 were studied in disproportionation reaction of toluene to benzene and xylenes. It found that mordenite zeolite catalyst modified by Pd2+, and cations are more active than the catalysts containing Ni2+, Co2+, Nd3+. It revealed that samples activated in terms of dry and humid conditions are characterized by fullest activity and selectivity. [ABSTRACT FROM AUTHOR]

The sorption and complex-forming properties of a modified sorbent based on a copolymer of maleic anhydride with methacrylic acid in regard to vanadium (V) were studied and main parameters of metal sorption determined. Sorbent containing fragments of N, N' – diphenyl – guanidine for the selective extraction of vanadium (V) from solutions were proposed. The sorbent was synthesized according to well-known methods. The optimal conditions for sorption were determined. The sorption was studied under static conditions. In the presented work, a main emphasis was laid on the study into the effect of pH of the medium, time, ionic strength, and metal concentration in a solution on the vanadium sorption. A maximum degree of vanadium extraction by the sorbent was achieved from pH 5 solutions. The influence of the ionic strength of the solution was studied by photometric method. Vanadium (V) was sorbed from solutions containing 0.1-1.4 M KCl. Results of the study showed that a significant decrease in metal sorption was observed in KCl solutions with a concentration of more than 0.6 M. Results of the analysis showed that the sorption equilibrium was achieved in 2 hours. As the concentration of vanadium in the solution increased, its sorption rose as well, and at a concentration of 8·10-3 M it reached maximum: static capacity = 253 mg/g. Also, we researched into possibilities available to determine the conditions for desorption of vanadium (V) with various mineral acids (HClO4, H2SO4, HNO3, HCl) after concentration on the proposed sorbent. Analysis results showed that vanadium (V) was quantitatively desorbed by 2 M HNO3. Multiple uses of the regenerated sorbent for concentration are possible. The degree of extraction of vanadium (V) under optimal conditions exceeded 95%. [ABSTRACT FROM AUTHOR]

The article deals with the influence of the concentration of butyl rubber and vulcanizing agents on the process of reactive extrusion of elastoplastics based on a mixture of thermoplastic polyolefins. The mechanic-chemical synthesis of dynamically vulcanized elastoplastics was carried out in the process of reactive extrusions. Single screw extruder with ratio L / D = 24 consists of 4 zones: loading zone, compression zone, dosing zone, extruder head. The number of turnovers of the screw was regulated using an asynchronous engine. The head is equipped with a slotted console enabling to obtain continuous sheets 2 mm thick and 100 mm wide. As thermoplastic polyolefins there was used the polyethylene of low density, polypropylene. Vulcanization of polymer mixtures was carried out using the dicumyl peroxide and sulfur. The mechanochemical synthesis of elastoplastics was carried out at different temperatures of the zones of material cylinder and extrusion pressure. The results of the study of the influence of extrusion process parameters on the melt flow rate of elastoplastics were presented. For a mixture of polyethylene and butyl rubber of low density the optimum temperature for zones of the material cylinder varied within 100− 150 ° C, and the extrusion pressure was 5.2 − 7.0 MPa. For a mixture of polypropylene and butyl rubber the temperature regime varied within 140-210°С and pressure of extrusion -7.2-9.4 МPа. To add elastoplastic properties to the polymer mixtures, vulcanizing agents such as dicumyl peroxide and sulfur were introduced into their composition. Selective influence of vulcanizing agents on the nature of changes of technological parameters of reactive extrusion and melt flow index was investigated. It found that dynamic vulcanic elastoplastics with unique compatibility of structures and properties can be obtained in at concentrations of dicumyl peroxide − 0.5 wt.% or sulfur−5.0wt.%. It revealed that dynamic vulcanic elastoplastics with unique compatibility of structures and properties can be obtained in the concentration of dicumyl peroxide− 0.5 wt.% or sulfur− 5.0wt.%. It established that the concentration of butyl rubber in the mixture of LDPE+PP− 10, 20, 30, 40 wt.% softening temperature, according to thermo-mechanical tests, varies accordingly in the range of 125, 107, 89, 78 °C. [ABSTRACT FROM AUTHOR]

The influence of the concentration of butadiene-nitrile-rubber and technological regime of injection moulding on the complex of main properties of elastoplasts based on thermoplastic polyolefins - low-density polyethylene and polypropylene, was considered. The use of dicumyl peroxide as cross-linking agent made it possible to obtain, in the process of mechanochemical synthesis, dynamically vulcanized elastoplasts with improved physico-mechanical and technological properties. [ABSTRACT FROM AUTHOR]