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Objectives. The main indicator that determines electrical conductivity of rubbers is specific volumetric electrical resistance (ρv ). The purpose of this work is to investigate changes in this indicator during swelling and deswelling of electrically conductive rubbers. When considering the swelling process of rubbers in liquid media at a molecular level, an analogy of this process with mechanical deformation of the material is drawn and common features and differences of these processes are revealed.Methods. For rubber compositions based on paraffinate and alkyl sulfonate nitrile butadiene rubbers, the degree of their swelling and the change in linear dimensions in heptane and in gasoline grades 80, 92, and 95 were determined. The ρ v value was determined by a potentiometric method: the initial value was measured after temperature control of rubbers for 1 h at 120°C, and the second measurement was carried out after these rubbers were swollen in the solvents for 48 h, followed by drying at 20°C to a constant weight and repeated temperature control under the same conditions. Using an IR Fourier spectrometer, spectra of the solvents used were obtained before and after identification of the investigated rubber samples in them.Results. It was shown that the type of rubber and solvent used influence the degree of rubber swelling. Rubber compositions based on natural rubbers with a large amount of attached acrylonitrile, obtained in the presence of an alkyl sulfonate emulsifier, have the highest resistance to swelling. The effect of the used solvent on the change in the degree of swelling is determined by its affinity for rubber and the presence of polar additives that increase the octane number of gasoline. It was established that the linear change of the samples upon swelling in the indicated solvents varies according to the length and thickness of the samples. Results show that depending on the type of rubber used and the degree of its filling, the described rubber processing technology leads to a decrease in the ρ v value by 2 to 20 times. The greatest effect of ρ v reduction is observed in low-filled rubber compositions based on paraffinate nitrile rubbers. The spectra of the frustrated total internal reflection of the solvents after their interaction with the studied rubbers show that particulate extraction of dibutyl phthalate, which was used as a plasticizer in rubber compounding, takes place as a result of rubber swelling.Conclusions. The proposed method of rubber processing reduces the ρ v value by removing dibutyl phthalate from the studied rubbers and forming a more developed carbon–elastomer structure. Furthermore, it solves the problem of the negative effect of the plasticizer on the ρ v value of rubber without excluding it from the rubber composition.

в работе изучены свойства композиции на основе модифицированных полиэтиленов. Полиолефиновые термоэластопласты были получены на основе этилен-пропиленовых эластомеров и полиэтилена высокой плотности двумя методами, в первом случае в качестве модифицирующего агента использовались серосодержащие соединения (альтакс, сера), во втором – ПДК. Термоэластопласты серии А получили совмещением исходных полимерных компонентов в расплаве на вальцах при температуре валков 433–453° К при зазоре между ними 0,2 мм. После плавления кристаллического термопласта добавляли этилен-пропленовый сополимер ЭПС и структурирующие агенты. Для достижения хорошей гомогенизации вальцевания осуществлялось в течение 25 минут. Рецептура композиций имела следующий состав (масс. ч.): СКЭПТ – 100; ПЭВП – 10–80; пероксид дикумила 1–2., the properties of a composition based on modified polyethylenes have been studied in the work. Polyolefin thermoplastic elastomers were obtained on the basis of ethylene-propylene elastomers and high-density polyethylene by the two methods: in the first case, as a modifying agent sulfur-containing compounds (altax, sulfur) were used, and in the second – MAC. Thermoplastic elastomers of the series A were obtained as a result of a combination of the original polymer components melt on the mill rolls at a temperature of 433–453 K° at the gap between them 0.2 mm. After crystalline thermoplastic melting ethylene copolymer problemby EPS and structuring agents were added. To achieve a good homogenization milling was carried out for 25 minutes. Formulation of the compositions had the following composition (pts. wt): EPDM – 100; HDPE – 10–80; dicumyl peroxide 1–2.

Актуальность работы обусловлена необходимостью исследований и разработки промывочных жидкостей для бурения геолого-разведочных скважин в сложных горно-геологических условиях Талнахского рудного узла. Цель работы: исследование влияния водных растворов простых солей и полиэлектролитов на гидратацию глинистых минералов при бурении скважин комплексами со съемными керноприемниками (КССК) на Талнахском рудном узле. Методы исследования: методы рентген-флюоресцентной спектрометрии, электронной микроскопии, рентгеноспектрального, спектроскопического и томографического анализа для определения минерального состава глинистых горных пород; гидратация глинистых минералов на тестере продольного набухания. Результаты. Проведены исследования гидратации монтмориллонита и иллита в растворах простых солей, водорастворимых полимерах и их комбинациях. Трансляционное движение молекул воды за счет наличия иона K-, обладающего отрицательной гидратацией, приводит к увеличению скорости проникновения молекул воды в поровое пространство глинистых минералов, независимо от их типов. В концентрированных растворах простых солей трансляционное движение молекул воды остается более интенсивным по сравнению с чистой водой, что приводит к дестабилизации горных пород, содержащих в своем составе глинистые минералы. Независимо от типа раствора пористость и проницаемость оказывают влияние на изменение линейных размеров глинистых образцов, что подтверждается графиками исследуемых образцов, изготовленных при разных давлениях. Полианионы и поликатионы способствуют более быстрому проникновению молекул воды в поровое пространство и далее в межплоскостное пространство глинистых минералов, что приводит практически к неограниченному набуханию. Скорость гидратации глинистых минералов замедляется в растворах, содержащих гидратирующиеся катионы (Ca2-, Mg2- ), стабилизация наступает за более длительный период, чем в случае с ионом калия. The relevance of the discussed issue is caused by the need to study and to develop drilling fluids for boring exploratory wells in difficult geological conditions of Talnakhskoe deposits. The main aim of the research is to study and assess the impact of simple salts and polyelectrolyte solutions on clay minerals hydration when drilling applying complexes with retrievable core receiver on Talnakhskoe deposits. The methods used in the study: methods of X-ray fluorescence spectrometry, electron microscopy, X-ray, spectroscopic and tomographic analysis to determine the clay mineral composition of rocks; hydration of clay minerals on the tester of longitudinal swelling. The results. The authors have studied illite and montmorillonite hydratation in simple salts solutions, water-soluble polymers and their combinations. Translational movement of water molecules due to the presence of K- ion which possesses negative hydration leads to increase in rate of penetration of water molecules into the pore space of clay minerals, regardless of their types. In concentrated solutions of simple salts the translational motion of water molecules is more intense in comparison with pure water, that results in destabilization of rocks containing clay minerals in their composition. Independently of the type of the solution, the porosity and permeability affect the change in linear dimensions of the clay samples, as evidenced by the graphs of the experimental samples made at different pressures. Polyanions and polycations facilitate more rapid penetration of water molecules into the pore space and further in the interlayer space of the clay minerals, which leads to virtually unlimited swelling. The rate of hydration of the clay minerals slows in solutions containing hydratable cations (Ca2-, Mg2-), stabilization occurs over a longer period than in the case of potassium ion.