[en] Full text: Expanding the practical use of products of radiation-vulcanized elastopolymers (RVEP) makes it necessary to increase their operational properties. Applied to the exploitation of polymers in the field of the ionizing radiation does not always meet shown requirements to them. In the present report the influence of sensitizer of disulpho chloride aromatic compounds on deformation-strength and their ageing under the influence of radiation exposure is being examined. The serial produced aromatic compounds of disulpho chloride bezene (DSCB) were used as sensitizers. It is established that, during the sensitization of radiation chemical vulcanization the mixture of butadiene-nitrile rubber with PVC with other ingredients affect the density of the spatial grid which determines the mechanical properties of vulcanized rubber. Two processes simultaneously run in the presence of sensitizing additives: inhibition of radiation oxidation which causes cross-linking and formation of the spatial grid in BNC. The role of sensitizer in the process of radiation vulcanization is defined first of all by reducing the doze of irradiation in the vulcanization process; simultaneously accelerate the cross-linking of the polymer chains. On the base of physical mechanical and structure of DSCB, can be judged that the influence of ionizing radiation leads the polar groups to ionization besides, their excited potential during ionization is very high which provides material with radiation resistance. Considering the resistance of DSCB to radiation, its practical value is high and can conduct vulcanization at low doses (150-300 kGy). (authors)

No abstract available

[en] Obtaining modified plasticizers as a result of crosslinking, improving the properties of their elastomers as a result of plasto-elastic, thermomechanical, diffusion and anti-burning effect, obtaining new types of elastomer materials by modifying polymer-based oil products using radiation-chemical method are considered interesting fields of research. In this regard, one of the important problems is to obtain new types of modified polymer plasticizers and to study the effect on many properties of the elastomer composition, as a result of crosslinking and dissolving in the oil-polymer molecule by the influence of gamma rays, by dissolving industrial petroleum oils with polymers in different weight ratios by the radiation-chemical method. In the research work it has been used an oil-polymer mixture obtained on the basis of industrial oils (U-61, 10W40) under the influence of gamma rays. As an industrial oil 10W40 (Azerbaijan) and U-61 (Russia) oils are used to prepare a composition. The composition was prepared with the presence of low-molecular compounds (HCPX, DFM, ZnO, P324). It has been shown that the effect of 500 kGy dose on the composite based on NBR and isoprene rubbers changes the amount of gel in the polymer macromolecule (70%), causing changes in the plasto-elastic properties of the polymer-based oil (plasticizer). Along with the change in carbon rubber gel, there is a 15-20% increase in Mooney viscosity. With the growth of the gel, there is an increase in the density of the chain network in the macromolecule, which leads to a decrease in plasticity by 50% (0.40-0.20). As the polymer plasticizer has a good diffusion rate in the polymer chain, it leads to a 25% time saving in the process of mechanical dissolution of the components (10 min). It was determined that the vulcanized elastomer mixture with the presence of other low molecular compounds in the composite system from 5.0 wt.h polymer-oil plasticizer under the influence of radiation reduces the hardness from 2500 gs to 1200-1500. As a result of the analysis of the vulcanized thermoradiation elastomer mixture (423K+5min+500 kGy), it was determined that the change in the hardness of the elastomer leads to an increase in elasticity. Experimental analysis determined the chemical transformations occurring in the chain molecule at the molecular level as a result of the influence of the plasticizer of the polymer oil NBR at the molecular level and the physical-mechanical properties of the vulcanisates obtained by the radiation method.

[en] Full text : Application and technological aspects of radiation vulcanization process of the chloroprene rubber and maleic acid in presence of different components were considered. The influence of different chemical bonds on the optimal complex properties of elastomers on the basis of new polyfunctional monomers was approved by radiation vulcanization

[en] Technically and financially, the advantage of neoprene elastomer over other synthetic rubbers is explained by the high (up to 70%) content of the polar C-Cl group, as well as cis and trans isomers, which cause changes in many properties of composite materials. Currently, in many countries around the world, the processing of neoprene rubber is carried out with the participation of sulfur and sulfur-containing compounds. Based on the prepared elastomer mixture, it can be said that since the average molecular weight of the obtained elastomers is above 500,000, a crystallization process with high strength and hardness takes place, which negatively affects its plasto-elastic and rheological properties. In order to overcome this problem, neoprene rubber BNK (SKN-18) is first modified with the presence of selected active low molecular weight compounds by applying new technology in laboratory conditions, using radiation-chemical technological methods. A new chemical structure (C-C) is formed in the macromolecule of the polymer as a result of the vulcanization process with the participation of a building agent and a sensitizer. This, in turn, causes a change in the properties of the obtained elastomer material. The main goal of the research work is to obtain an elastomeric material with high technical indicators by applying the radiation-chemical technological process. For this, the following scientific and technical experiments were carried out: By modifying Neoprene and BNK rubbers in different proportions, changing the amount of cis-trans isomer in Neoprene rubber and by increasing the unsaturation in the polymer chain, changing the sol-gel properties as a result of the effect of two polar groups (C-C, C-Cl) in the polymer chain due to the newly formed double bonds; Based on the prepared mixtures, building systems with the presence of a new active building agent, maleic acid diallyl ether (MTDAE), as a sensitizer, diaminophenylsimim triazine (DAFST) as a plasticizer, epoxy resin (ED-5), activator zinc oxide, and technical carbon, radiation of each of the selected components, to determine the process of destruction and construction of a macromolecule in a chemical process; To study the chemical transformations that occur in the macromolecules of the polymer composite systems as a result of the effects of both gamma rays and thermo radiation. As a result of the change in plasto-elastic and rheological properties under the influence of 500 kGy gamma rays, it was possible to lower the molecular weight of the polymer. This change made it possible to maintain the average molecular mass and the hardness and flexibility of the material. A capillary viscometer was used to determine the rheological properties of the composites obtained by all three technological methods (temperature, gamma, and thermo radiation). Research studies have shown that more effective changes occur in the polymer chain due to the effect of thermo radiation. In the IR-Fourier spectrometric analysis, an ionic molecular reaction can be assumed based on the change of intensity lines with intensities of 700, 970, 1240, and 2230 cm as a result of thermo radiolysis in the presence of Neoprene BNK and low molecular weight components.

[en] Due to the increasing use of elastomeric materials (EM), one of the requirements is their resistance to aggressive media (elevated temperature and radiation). Therefore, data relating to the ageing behavior of EM in aggressive media are of direct application value. In the present work, the processes of vulcanization of mixtures based on NBR (SKN-40M), as well as the establishment of their aging in fuel and under the influence of radiation, are studied. As the object of research, we used SKN-40 grade NBR; elastomeric mixtures were prepared according to the given recipe in the presence of 3.0 wt.% hexachloroparakisilol, 5.0 wt.% epoxy resin and 5.0 wt.% zinc oxide and the samples were vulcanized in an electric press at 150 C for 25 minutes. Similar experiments were performed for thermovulcanizates during their aging under the influence of an absorbed radiation dose (1000-2000 kGy). The work consisted of three stages: 1. Development of structuring systems for rubber SKN-40 M, 2. Study of the structural parameters of vulcanizates. 3. Study of the effect of temperature and radiation on the aging of elastomers in air and in fuel. The process of vulcanization of elastomeric mixtures with the participation of hexachloroparaxysilol and epoxy resin has been studied. Using the method of viscometry and sol-gel analysis, the structural parameters in thermovulcanizates were studied. Changes in polar groups in thermal and irradiated thermovulcanizates were determined. Properties of elastomers at 473 K temperature and at radiation (1000-2000 kGy) ageing have been determined by changing the accumulation of residual strain, stress relaxation and equilibrium modulus in air and in fuel. It is shown that some decrease in the degree of crosslinking and polar groups at high temperature (150-200 C) is probably due to an increase in the contribution of structural processes during their aging in fuel and under the influence of radiation. In contrast to the thermal aging of an elastomer, there is no correlation between the rate of residual strain accumulation and the rate of stress relaxation during radiation aging. The residual strain of the elastomer at doses of 1000-2000 kGy increases monotonically and amounts to 40-45%, i.e. in this case, the elastomer should practically not work as a sealant. Voltage at a dose of 2000 kGy drops by no more than 20-30%. Thus, the evaluation of the radiation resistance of elastomeric materials can be given both by the change in stress relaxation and by residual strain. When choosing elastomeric materials for operation under dynamic conditions and other types of aging, radiation resistance should be characterized by changes in dynamic characteristics.