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Introduction. Polyethylene is the most widely used material in various fields of the national economy, and products made of it have essential advantages, such as lightness, insolubility in organic solutions with quite satisfactory strength. However, the mechanism of its destruction is quite complex and depends on the working conditions and substances, which are in contact with it. The research purpose was to study the polyethylene resistance to oil and associated water under the static and dynamic conditions and at room temperature.Methods and Materials. The research was carried out on a laboratory device for passing various liquids (oil, associated and distilled water) in polyethylene pipes, assembled by the author of the article. While working, methods of statistical and dynamic data processing were applied.Results. Based on the results of previous experiments, graphs were plotted for the change in the weight and volume of immersed granules over time. They have shown that polyethylene has a quadratic dependence, and diffusion for the three liquids studied in this work (distilled water, accompanying water and oil) is described by Fick's law. This indicates the fact that the rate of liquid diffusion through polyethylene is the key factor.Discussion and Conclusions. The obtained results have shown that the rate of liquid diffusion through polyethylene is the key factor. Immersion in oil has a greater impact than immersion in associated or distilled water due to the presence of salts. It has been found out that the relative change in the weight and thickness of the polyethylene pipe walls through which oil passes is greater than those through which the associated water passes. Moreover, the microscopic cross sections images in the samples before and after the tests have confirmed the obtained results.

Objectives. To obtain and study the properties including degradability of polymer composite materials (PCM) based on low-density polyethylene (LDPE) obtained by introducing an environmentally friendly additive comprising an oxo-decomposing additive (ODA) based on an amphiphilic polymer-iron metal complex, which accelerates the process of polymer degradation.Methods. PCMs based on LDPE and ODA were produced by processing in laboratory extruders in the form of strands, granules, and films. Thermodynamic properties were determined by differential scanning calorimetry in the temperature range 20-130 °C. In order to assess the performance characteristics (physical and mechanical properties) of the PCM, tensile strength and elongation at break were determined. The biodegradability of PCM was evaluated by Sturm's method, with the biodegradation index being determined by the amount of CO2 gas released as a result of microorganism activity, as well as composting by placing the PCMs for six months in biohumus. Changes in physical and mechanical properties and water absorption of the films during storage were evaluated. The photochemical degradability of the PCM was determined by exposing it to ultraviolet radiation for 100 h (equivalent to approximately one year of exposure of the films under natural conditions). The appearance of the composite samples following removal from the biohumus was determined using an optical microscope with ×50 magnification in transmitted and reflected light.Results. Following biodegradation by composting, the physical and mechanical properties of PCMs decrease by an average of 40.6%. This is related to the structural changes that occur in composites during storage in biohumus, i.e., the formation of a looser structure due to the development of large clusters of microorganisms that affect the formation of microcracks. It leads to the stage of fragmentation of the polyethylene matrix and indicates the progress of biological degradation of composites. In this case, the water absorption of the composite samples was 63% after 96 h of exposure. The biodegradability index determined by the Sturm method after 28 days of bubbling had changed by 82%, indicating an intensive biodegradation process. Exposure to ultraviolet radiation for 96 h resulted in the complete destruction of the PCMs, which turned into small “flakes.” This method is the most effective for the degradation of LDPE- and ODA-based PCMs.Conclusions. According to the results of the study of ODA-containing PCMs based on an amphiphilic polymer-iron metal complex, the tested filler-modifier can be recommended for the production of PCMs offering an accelerated degradation period.

ABSTRACT: Introduction. Polyethylene is by far the most widely used polymer in the production of wood-polymer composites both in Russia and in other countries. Nevertheless, these composites have a number of disadvantages: low adhesion between polymer matrix and wood filler, which reduces the strength characteristics of the products, high elasticity, and low weather resistance. In industry, such issues are often solved by using complex additives in the form of granules including binding agents, lubricants, and various thermo- and UV-stabilizers. Methods and materials. New experimental data on technological and operational characteristics of wood-polymer composites (WPC) based on low-pressure polyethylene modified with complex processing additive have been obtained. In addition to stabilizers and lubricants, multi-wall carbon nanotubes (MWCNT) were introduced in WPC to facilitate the extrusion process, their content was 30% of the total composition. WPC-based products are mainly intended for outdoor performance under mechanical load, which places special demands on them in terms of strength, weathering and water resistance. Results. An increase in the mechanical characteristics was found for WPC after the introduction of the complex additive: at a concentration of 2.6 phr, the tensile strength increased by 35%, and at 53.3 phr, the flexural strength became higher by 12%. The introduction of the additive led to a decrease in the abrasion and water absorption of the modified sample compared to that of the initial material. Regardless of the additive content, all the samples were uniformly colored, which indicated a uniform distribution of the modifier over the volume of the WPC melt during processing in the extruder. Conclusion. The introduction of a complex processing stabilizing additive into the composition of a wood-polymer composite based on polyethylene was carried out. The results of the research showed that the additive in a wide range of concentrations contributes to the improvement of the technological and operational properties of the resulting composites

Relevance. The questions of research of physical and chemical characteristics of reinforcing tapes, peculiarities of chemical connection of composite material and reinforcing component of the splint, physical indicators of strength of their connection, optimal thickness of composite material for reinforcing tape covering remain not fully studied and require further work in this direction in order to optimize splinting stages of mobile teeth in various clinical situations and nosological forms of diseases. The aim of the study - to study the microscopic structure of splinting constructions containing in their structure reinforcement tapes based on organic and inorganic matrices. Material and research methods. 10 groups of 10 specimens of splinting construction, with different chemical composition of reinforcing tapes, 8 of which were made using tapes based on inorganic matrix, 2 - based on organic. Results of the study. Microscopic examination of the splinting samples showed good integration of the composite polymer matrix into the structure of the tapes in the samples using inorganic matrix-based tapes. Peripheral layer delamination was not detected, pores in the splint thickness were absent or were single, which may be due to silanization of glass fibers incorporated into the thermoplastic polymer and light-curing composite matrix. Conclusion. Resin-impregnated inorganic parallel fiberglass tapes impregnated in the factory showed an advantage compared to woven and braided tapes and unimpregnated tapes.

The neutron activation analysis for short-lived radionuclides at the WWR-K uses a pneumatic transport system (Austria) with specific transport capsules. The irradiated samples are not removed from the transport capsules and are measured directly in the capsule. It is necessary to take into account the fact that the induced activity of the capsule material itself acts as the background radiation in relation to the induced activity of the sample under study. A study of the capsule material and the polyethylene tubes used as sample fixing devices in the center of the transport capsule was performed. Earlier it was found that the HDPE T50 capsule material contains impurity elements Ti, Cl, Al, Na, Ca. It was found that the fixing material contains a larger amount of impurities, which leads to the increase of spectrometric equipment loading and to the increase of relative contribution of individual radionuclides to the final spectrum. The induced activity spectra were analyzed and processed, the content of elements in polyethylene was calculated and it was shown that the analytical signals of Mg-27, Mn-56 and Sb-122m, Cr-51 and Sb-122 refer exclusively to the induced activity of the fixer-tube material. This circumstance does not allow to determine small concentrations of these elements in the samples themselves. The necessity of search of other more pure material for its use as sample fixers at placement in a transport capsule is shown. [ABSTRACT FROM AUTHOR]

Over the past few years, a group of new processes was developed for high-temperature, including plasma electric arc spraying (at ambient pressure) and spheroidizing of some ceramic and metal powder materials with the use of gaseous hydrocarbons in the heat carriers as well as with feeding of organic additions into a high-temperature jet, in particular, polymeric ones, to control porosity of sprayed metallic functional coatings. The paper considers the possibility to modify such technological processes by introducing solid fuel additions of a polymer type into the operating fluid of an apparatus for gasthermal (plasma or other) treatment, which provides melting of metal or oxide powders. For this, with the help of thermodynamic analysis, the processes have been evaluated at temperatures (300–3000) K for the set of such reacting five component systems as C–H–O–N–Me (at ambient pressure 0.101 MPa) with five variants of Ме – aluminum, titanium, chrome, copper, nickel. This makes it possible to consider these systems as simulants for potential technologies for the treatment of oxide powders (Al2O3, TiO2, Cr2O3) as well as metallic ones (Cu, Ni and their alloys). In order to obtain high exothermic contribution to the heating of powders, the combination “air + polymeric addition (polyethylene) of LDPE grade” was chosen as mixed heat carrier (operating fluid) for the basic version of simulated process. During the analysis of equilibria for the considered multicomponent systems (17 variants), a set of following parameters has been used to characterize the energy intensity of the target powder heating process: the equivalence ratio for reacting mixture and its adiabatic temperature; the energy efficiency of material heating with and without taking into account the effect of fuel addition; specific energy consumption for the powder melting; autothermicity degree of the process during the combined heating (electrothermal heating by the arc of plasma torch and heat flux from the “air + solid fuel additions” mixture) of refractory powders. As a result of the assessment, the preferred (from thermodynamic standpoint) regimes of the considered processes have been found and the possibility to realize an energy-efficient heating of these oxide and metal materials (without oxidation of the latter to CuOx, NiO) with a reduced part of the electric channel of energy transfer, resulted from the carrying out of appreciable effect of the fuel-initiated mechanism of heating in the analyzed C–H–O–N–Mesystems, has been shown in the paper.

The sanitary and hygienic safety of modern packaging is determined by the layer of packaging material in direct contact with the food product. This layer in most cases is a synthetic polymer of the polyolefin class — low density polyethylene. This material is used as a stand-alone packaging and in multilayer and combined packaging materials. During thermal and photooxidation, compounds can form in it that negatively affect the safety of the package, which can migrate into the product. Food technologies use methods of disinfecting packaging materials and packaging before filling or bottling products. These methods include ultraviolet irradiation of the surface, which has a bactericidal effect. Using spectral methods of analysis, researches have been carried out on changes in the polyethylene layers structure in the film’s composition, multilayer films and combined packaging materials when exposed to pulsed ultraviolet radiation in a wide spectral range (irradiation with a pulsed xenon lamp). Deformations of polyethylene macromolecules chemical bonds on the surface and boundary layers under the influence of pulsed UV-irradiation have been revealed. The IR spectra of ATR (Attenuated Total Reflection) were obtained, the analysis of which showed that the monofilm is subject to the greatest destructive effect, as evidenced by the appearance of characteristic absorption bands responsible for the formation of aldehyde, ketone groups, as well as for the polymer chain termination. It is shown that the use of food soot in the composition of multilayer packaging films blocks their photo destruction. Upon irradiation of a combined material based on cardboard intended for bottling milk, an absorption band was found in the spectra, which is responsible for the onset of the destruction process with the formation of aldehyde and carboxylate groups with the formation of aldehyde and carboxylate groups.Comparison of changes in structure in three different packaging objects containing a polyethylene layer shows the feasibility and necessity of using combined and multilayer materials for food products packaging, in which, even under extreme UV-irradiation, there are practically no photo destruction processes, which is confirmed by spectral researches.

Polyethylene (PE) and polyvinyl chloride (PVC) are used in many areas of human activity, in the production of various goods, which is carried out mainly on the basis of imported raw materials. This production is almost entirely focused on the domestic consumption, and the pricing policy directly depends on customs duties and taxes. On the Ukrainian market are presented imported fabricated products with uprated specification, in particular, pipe products made of polymeric materials. The article is aimed at studying the volumes and structure of export-import operations of Ukraine in terms of the group «Polymeric materials, plastics and products from them», identifying problems and prospects of Ukrainian producers of pipe products and their participation in foreign economic activities. The analysis of structural changes in volumes and balance of the foreign trade in goods and services of Ukraine in dynamics is carried out; the volume of export-import operations in goods is determined; averages for the period are computed. The participation of Ukrainian enterprises in the implementation of foreign economic activities is characterized, including: quantity, regional placement in the territory of the country, the average volume of operations. The volumes and dynamics of export-import operations in the group 39 «Plastics, polymeric materials», both the commodity and the geographical structure are analyzed. The authors consider the main producers of fabricated polymer-pipe products together with the producers of domestic raw materials, their proportion in the sale of goods in the foreign market; the suppliers of imported raw materials and the impact of changes in customs tariffs and fees on prices. The range of average export-import prices for 1 kg of polyethylene pipes for the top five countries is calculated. Market problems are identified and the relevant recommendations are made.

Objectives. Determination of the influence of molecular weight on the modulus of elasticity, yield, strength, and retardation processes in polyethylene.Methods. We used vane samples (thickness: 4 mm; length: 100 mm; width.: 10 mm) made by injection molding at p = 60 MPa, T = 210 °C, τ = 15 s from the following polyethylenes: HDPE 27773 (Stavrolen, Lukoil, Russia); BorSafe HE3490-IM (Borealis, Austria; black); CRP 100 Hostalen (Basell Polyolefins, Netherlands; black); Stavrolen PE4PP-25B (Stavrolen, Lukoil, Russia; black). The samples were in accordance with the defined standards for the AL 7000 LA-5 tensile testing machine. The study of relaxation characteristics was carried out in two modes: relaxation and retardation.Results. We obtained stress-strain diagrams at various temperatures under isothermal conditions (T = const) and determined the influence of polyethylene molecular weights on the modulus of elasticity, yield, and strength of polyethylenes. We have shown that under isothermal conditions, when the stress equals the yield strength, the removal of the external action results in a two-stage response. The first stage is the stress relaxation. The second stage characterizes the elastic features of the studied materials under the external action ε = const.Conclusions. We have established that temperature increase affects the physicomechanical characteristics of polyethylenes differently, depending on their molecular weights. The experiments have shown that when the stress exceeds the yield strength, at constant deformation, there is a complex response of the polyethylenes to external action. This response is characterized by two stress stages throughout the course of time. The first stage is characterized by asymptotic decrease in stress down to a constant value; the second stage is characterized by constant stress throughout the course of time. We have determined relaxation times for the relaxation stage (stage I) and calculated activation energy. We have also established that the activation energy depends on molecular weights of the polyethylenes. It has been shown that an increase in polyethylene molecular weight leads to a decrease in relaxation time and activation energy.

Background. Polyethylene (PY-342) and polyamide (PA-6) are the largest-tonnage, available and demanded from the whole range of polymers produced by the industry. Therefore, the search for technical solutions aimed at simplifying the processing of polyolefins and creating new types of composite materials based on them is an urgent task. Purpose: to study the possibility of creating thermoplastic composites based on polyolefins (PO) with improved properties (physical, mechanical, physicochemical, thermophysical, electrophysical, magnetic, optical, etc.). Methodology. The physical and mechanical properties of filled polypropylene and polyamide compositions, the melt flow rate were determined by viscometry, flexural strength (two-support bending), Charpy impact strength. Originality. The rheological characteristics of composite materials based on polyethylene with metal oxides have been determined. Findings. To obtain a composite material based on polyethylene the content of metal oxides was changed from 1 mass to 5 mass parts. Evaluation of the rheological properties of filled composites showed that with an increase in the content of metal oxides, the fluidity of the compositions decreases, but the resulting compositions can be processed by injection molding. The data obtained show that the optimal are compositions containing: 5 mass.h. metal oxides. [ABSTRACT FROM AUTHOR]

Introduction. Polymeric materials (PM) are increasingly used in various industries and agriculture. Under the action of UV light, PM are destroyed. UV stabilizers are used to protect PM from photodegradation. Their action is based on the absorption of the photoactive sunlight component or on the deactivation of excited molecules that have already absorbed a light quantum, as well as on the inhibition of dark light-induced reactions. The work objective is to provide a comparative analysis of compounds of the sterically hindered phenols (SHP) series and nitroxide radicals (NR) as the PM photodegradation inhibitors.Materials and Methods. Reagents of the “purum” grade, LDPE premium grade 15803-020 polyethylene film were used for the investigations. The stabilizer was applied to the film by dipping. Carbonyl groups in polyethylene were determined by IR spectroscopy. IR spectra were recorded on Varian-640 instrument.Research Results. 2,4,6-tri-tert-amylphenol (1), 2-methyl-4,6-di-tert-butylphenol (2), 4-acetylamino-2,2,6,6-tetramethylpiperidin-1-oxyl (3), 3-carboxamido-2,2,5,5-tetramethylpyrrolin-1-oxyl (4) were tested as stabilizers for photo-oxidative degradation of polyethylene. It is known that the accumulation of carbonyl and hydroxyl groups is recorded in PM samples under irradiation in the process of photodegradation through the IR spectroscopy. The absorption band of the carbonyl group at 1720 cm- 1 appears in the IR spectra of oxidized polyethylene. The IR spectra analysis shows that the content of carbonyl groups in the check samples is significantly higher than in the samples treated by stabilizer solutions.Discussion and Conclusions. The experiments show that ni-troxide radicals of 3-carboxamido-2,2,5,5-tetramethylpyrrolin-1-oxyl series and 4-acetylamino-2,2,6,6-tetramethylpiperidin-1-oxyl are the best photostabilizers of polyethylene. Moreover, there is no significant difference between the radicals of the 2,2,6,6-tetramethylpiperidine and 2,2,5,5-tetramethylpyrroline series. Sterically hindered phenols, under photodegradation, have a far smaller stabilizing effect, falling short of nitroxide radicals.

Radiation effect on the PA/PE/Eva film material with a thickness of 55 μm was investigated at theBurnazyanCenterusing radiation processing plant (RPP) with the UELR‑10–10–40 accelerator at 10 MeV. Polymer films were irradiated with doses of 0 to 18 kGy. The study of IR spectra showed that when processing the PA/PE/Eva film with fast electrons with a dose of up to 18 kGy using the UELR10–10–40 plant with a power of 10 MeV the number of functional -CH3 and -NHgroups in the IR spectra changes to 0.0060 relative units with radiation doses of 12 to 18 kGy, which leads to degradation of the sample and its crosslinking simultaneously. Using confocal laser microscopy, it was demonstrated that after irradiation of PA/PE/Eva sample with doses of 18 kGy, the surface of the film becomes smooth in РА layer and in Eva layer, and a spot thinning of the sample occurs. These characteristics may cause a change in the barrier properties of the film material and affect the shelf life of food in a packaging.

Currently, halogen-free cable compositions are becoming increasingly common in the manufacture of cable compositions. The concept of halogen-free or “zero halogen” becomes a symbol of fire resistance, low-smoke characteristics, low toxicity of volatile products of combustion, the absence of the toxic, corrosive and irritating gas - hydrogen chloride - and other hydrogen halides in the volatile products. More and more manufacturers of cable products are beginning to pay increasing attention to the problems of processing, toxicity and fire safety. It should be noted that the requirements for improving the fire safety of cable products are constantly becoming tougher, since the main problem of most of these polymeric materials is their flammability, high smoke generation and high flame spread rate. In this regard, there is a burning question to increase these characteristics and bring them to the level of compounds based on PVC. The main way to increase the flame-retardant characteristics of halogenfree cable compositions is to introduce mineral fire retardants into these compositions. The study of the composition and packaging of these mineral fillers-flame retardants makes it possible to increase the level of flame-retardant characteristics of halogen-free cable compositions. The paper presents the results of studies on the thermal stability of cable compositions based on PE + EVA mixtures containing magnesium hydroxide crystalline hydrate as a filler-flame retardant. It is shown that cable compositions containing magnesium hydroxide crystal hydrate are characterized by higher heat resistance and thermal stability (~ 2-fold) compared to a polymeric matrix based on PE + SEVA. This allows to process them at high temperatures (more than 200°C) by extrusion and pressure casting.

The paper discusses methods for increasing stability of polyethylene’s electret state by adding diatomite particles to its composition. The results of studying the IR spectra, the studied materials’ temporal and temperature stability are presented. Mechanisms for improving the stability of the composite polyethylene’s electret state are discussed.

Objectives. The main idea of the present study was the production of polymer composites based on synthetic isoprene elastomer and low-density polyethylene containing nanoparticles of carbon black and aluminium in various amounts.Methods. An exponential approach was used throughout the study to better control the region of small additives; this control was impossible to achieve using a linear distribution of nanofillers among the small additives. The composites were filled with nanosized aluminium and DG-100 carbon black particles with a specific adsorption surface of 100 m2 /g and having an average particle size of 20-30 nm. Electrophysical parameters were measured by conventional techniques of electron microscopy, electron shadow microscopy and hydrostatic weighing. Maxwell-Wagner theory and polarisation model were applied.Results. For a composite containing 80% of isoprene synthetic rubber (SCI-3) and 20% of low-density polyethylene, the dielectric permeability and specific volume resistivity dependences were studied experimentally and their graphs were plotted against the concentration of nanosized particles of aluminium and carbon black fillers. The features of these curves were considered. It is shown that, for small amounts of Al and carbon black nanoparticles in the composite, significant changes (extrema) take place on the curves ԑ '= ԑ' (C) and ρᵥ = ρᵥ (C), which do not conform to the Maxwell-Wagner polarisation model. For some heterogeneous polymer mixtures, a distribution of carbon black particles was observed that led to a superadditive electrical resistance.Conclusion. It is shown that for small amounts of Al and carbon black nanoparticles in composite materials, significant changes (extrema) take place on the curves ԑ '= ԑ' (C) and ρᵥ = ρᵥ (C) that do not fit within the framework of the Maxwell-Wagner polarisation model.

The paper considers a possibility to use sand asphalt concrete as a material for protection of asphalt concrete and cement concrete road pavements against affection of external destructive factors. Advantages and disadvantages of sand asphalt concrete road pavements have been determined in the paper. The paper provides recommendations on improvement of sand asphalt concrete properties and contains an analysis of possible variants for usage of complex-modified sand asphalt concrete in the road construction. It has been noted that according to its potentially possible physical and mechanical properties activated quartz sand being micro-reinforced by dispersive industrial wastes is considered as an efficient component for creation of constructive layers in road asphalt concrete pavements. The paper reveals only specific aspects of the efficient application of quartz sand in road asphalt concrete. The subject of the paper loоks rather interesting for regions where there are no rock deposits for obtaining broken-stone ballast but there is rather significant spreading of local quarts sand. Its successful application is connected with the necessity to develop special equipment for physical and chemical activation of sand grain surface that permits strongly to increase an adhesive strength in the area of phase separation within the “bitumen–SiO2” system. The considered problem is a topical one and its solution will make it possible to local sand in a maximum way and partially to exclude application of broken stone in road construction.

The polymer material (РА/РЕ/Eva) with a width of 55 μm was studied. Sterilization was carried out on the unit GU–200 at doses from 3 to 18 kGy in the Research Institute of Technical Physics and Automation, Rosatom, Moscow, Russia. The structure of the polymermaterial samples was studied by IR spectroscopy before and after irradiation in a range of 400–5000 сm–1. According to the results of the analysis of the IR spectrum structure, the changes in the structure were insignificant upon irradiation at doses up to 6 kGy. Upon irradiation at doses from 9 kGy and higher, an increase in quantity of ester groups (2340 сm–1) and insignificant increase in other functional groups were observed, which can suggest a simultaneous process of intra-molecular cross-linking with the intermediatestage of cross-linking occurring with formation of vinylene groups. This causes destruction of a polymer material and radiation oxidation. These disorders can lead to changes in physico-mechanical and barrier parameters of a polymer material, which can be notably reflected in the shelf life of agricultural products.

Copyright of Electronic Processing of Materials / Elektronnaya Obrabotka Materialov is the property of Institute of Applied Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nanosistemi, Nanomateriali, Nanotehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

High-strength polyethylene films containing 0.5-1.0 wt. % of nanocrystalline silicon (nc-Si) were synthesized. Samples of nc-Si with an average core diameter of 7-10 nm were produced by plasmochemical method and by laser-induced decomposition of monosilane. Spectral studies revealed almost complete (up to ~95 %) absorption of UV radiation in 200- 400 nm spectral region by 85 micron thick film if the nc-Si content approaches to 1.0 wt. %. The density function of particle size in the starting powders and polymer films containing immobilized silicon nanocrystallites were obtained using the modeling a complete profile of X-ray diffraction patterns, assuming spherical grains and the lognormal distribution. The results of X-ray analysis shown that the crystallite size distribution function remains almost unchanged and the crystallinity of the original polymer increases to about 10 % with the implantation of the initial nc-Si samples in the polymer matrix.

The rheological properties of polyethylene with different molecular weight characteristics were studied. Difference of molecular weight characteristics was found on the basis of melt flow index, and slip effect in the molten polyethylene flow was studied. The presence of slip effect is found in case of flowing polyethylene with a higher molecular weight in contrast to polyethylene with lower molecular weight at different temperatures. Changes of the slip effect parameters upon mixing polyethylenes with very much different molecular weight characteristics were studied.

Copyright of Electronic Processing of Materials / Elektronnaya Obrabotka Materialov is the property of Institute of Applied Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The effect of the low quantity of renewable functional additives on polyethylene degradation has been studied. Modified soybean and rapeseed oil as additives were used and added in an amount of 1% of the weight to the polyethylene compositions. The strength characteristics of the compositions after UV irradiation and the effectiveness of modified vegetable oils were established. It's shown that the loss of strength of the composites after UV-irradiation was equal to 38 and 55 % and loss of elongation - 88 and 96% for rapeseed and soybean oil, respectively. The thermal destruction of polyethylene compositions with functional additives by pyrolytic mass spectrometry was studied. An analysis of the results shows that structural transformations take place due to the added renewable additives, which are fixed by mass spectrometry. It is revealed the number and intensity of ion fragments are higher for the composites containing additives than for the initial PE. [ABSTRACT FROM AUTHOR]

Samples of the «polyethylene — VO2» composite have been obtained using technologies for manufacturing self-healing polyswitch fuses. The volume fraction of vanadium dioxide in the samples ranged from 0,25 to 0,6. It is shown that the electrical conductivity of the composite is of percolation character. The paper presents research results of the microstructure, the resistance temperature dependence and current-voltage characteristics of polymer composite samples, as well as the impact of the VO2 content on the samples.

Mechanical properties of composites based on polyethylene and rubber powder (10-800 µm) at high temperature (20-80°C) was investigated. The tensile strength of the composites within the rubber powder content from 36 to 66 vol. % practically does not change as filing rate increases, but decreases as temperature rises. The influence of rubber powder concentration on deformation at rapture is determined by investigation temperature.

The influence of external factors, including mechanical processing modes on quality characteristics of treated surfaces of polymer composite materials are investigated. Determined that when polyethylene-based polymer composite material is drilling by R6M5 drill the best quality of the holes observed by cutting speed 1,4 m / sec. Key words: composite materials, cutting tools, handling, wear resistance, quality. [ABSTRACT FROM AUTHOR]

Two methods of rooting of Zelkova softwood cuttings were analyzed: (1) quick-dip method and (2) contact method - the thin polyethylene film (20 mm) laid directly over the cuttings during the rooting process. The control for contact method was a low tunnel with a thick polyethylene film. One group of cuttings in the contact method was treated with quick-dip (IBA 2,500 μg.mL-1, carrier - ethyl alcohol) during 5 sec, and the other group was treated with water solution of IBA (50 μg.mL-1) in 24-hour treatment. The third group was control - untreated cuttings. The same groups of cuttings were also used in low tunnels. The number and length of primary and secondary roots were measured on rooted cuttings. The results of all treatments show that contact method in combination with water solution of IBA was the best with 92% of rooted cuttings. No significant differences were obtained between this treatment and quick-dip + contact method (85.3%). Rooting of cuttings under low tunnel was significantly lower. In general, contact method was better than low tunnel, disregarding the carrier used. These results recommend the almost unknown contact method in nursery propagation of Zelkova, as an alternative, non-invasive species for the conditions in Serbia [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]

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]

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]

We consider the research of the cascade extruder with a disk melter-gomogenizer and a melt supercharger in the form of the gear-type pump. We also present our research results of processing high pressure polythene of grade 15803-020 in the form of nomogram aimed at determining the extruder's operating mode. [ABSTRACT FROM AUTHOR]