Method of obtaining carbon nanomaterials

FIELD: chemistry.

SUBSTANCE: invention can be used for obtaining carbon nanotubes and nanofibres. Solid disperse catalyst is periodically loaded into reactor, gases are injected and subjected to contact with catalyst particles at the temperature of carbon nanomaterial synthesis. Loading of each following portion of catalyst is performed on the layer of growing nanomaterial. Alternate pressure of gaseous medium is created in reactor by injection of gases when pressure in reactor increases and their discharge, when pressure decreases. Stages of injection of gases into reactor and discharge of gases from reactor are performed by repeated periodical creation of vacuum in lock-chamber.

EFFECT: simplification of hardware process realisation, increased productivity due to uniform catalyst distribution.

2 cl, 2 dwg, 2 ex

 

The invention relates to the technology of carbon materials, specifically to the technology of production of carbon nanomaterials, including nanotubes and nanofibers, the method of chemical deposition from the gas phase.

Hereinafter in the description the following terms are used, which, although they are generally used by experts in the field of technology, but require clarification in the context of the claimed invention.

The term "carbon nanomaterial" - CNM, can mean carbon nanotubes, carbon nanofibers, and other nanostructured forms of carbon.

The term "Chemical deposition of carbon nanomaterials from the gas phase" (common English designation CVD - Chemical Vapor Deposition) means that the particles of the dispersed catalyst or a catalyst layer deposited on any porous, fibrous or flat substrate, is brought into contact with the gas-carbon source, which can be used carbon monoxide, hydrocarbons, alcohols, amines, and other organic substances. When the respective values of technological parameters (temperature, pressure, concentration, flow velocity components) of a substance is the source of carbon is decomposed on the catalyst particles on the carbon and gaseous products, and released the carbon crystallizes in the form of nanostruct the s.

There are various ways of producing carbon nanomaterials using CVD technology. Next, we consider those that are closest to the claimed technical solution.

There is a method of producing carbon nanotubes, in which solid catalyst particles and particles growing on them carbon nanotubes supported in the state of the fluidized bed due to the transmission of the upward flow of gas through the layer of solid particles. In relation to the production of carbon nanotubes this method is described in many publications. As an example we can cite the work of [1] Morancais A., Caussat Century, Y. Kihn, Kaick P., D. Plee, Gaillard, P., Bernard D., P. Serp A parametric study of the large scale production of multi-walled carbon nanotubes by fluidized bed catalytic chemical vapor deposition // Carbon, 2007, vol. 45, p.624-635. [2] Y. Wang, F. Wei, G. Luo, Yu PL, Gu G. The large-scale production of carbon nanotubes in a nano-agglomerate fluidized-bed reactor //Chemical Physics Letters, 2002, vol.364, p.568-572. [3] H. Yu, Q. Zhang, F. Wei, W. Qian, Luo G. Agglomerated CNTs synthesized unit in a fluidized bed reactor: Agglomerate structure and formation mechanism // Carbon, 2003, vol.41, p.2855-2863. The gas mixture passed through a layer of solid particles, typically contains an inert gas and a gas source of carbon, usually hydrocarbons (ethylene, propylene, methane, propane-butane, and others). By adjusting the speed of the gas flow, the support layer in a fluidized condition. Some of the most fine particles which are carried away by the gas stream from the reactor, cyclone catch and return is up in the reactor. System recovery and return to the reactor fluidized bed of small particles using a cyclone is well known [4] Perry, R.H., Green D.W. Perry's Chemical Engineers' Handbook. Me Graw Hill Companies, Inc. 1999.

The growth of carbon nanotubes (CNTS) hold at a given temperature, supported by means of a heating device and Comptroller.

The advantage of the method fluidized bed is relatively high productivity per unit volume of reactor. As the gas stream moves relative to the catalyst particles and through the layer of catalyst particles can skip any given volume of gas-carbon source, the growth of carbon nanoparticles in this way is not limited.

The disadvantages of the considered solutions are the following. The speed of the upward flow of gases through the reactor is determined by the conditions of maintaining the fluidized state of the layer of catalyst particles together with growing on them particles CNM. At too low speed layer ceases to be fluid, at too high a gas flow rate of solid particles are carried out of the reactor, forcing complicate the device, using the device to capture rendered particles and return them to the reactor. This bounded on two sides by the velocity of the gas stream may differ from the speed of supply of gases, optimal the Noi for the efficient growth of CNM. In addition, with the rise CNM physical layer parameters (density, size of particles and their agglomerates) are changed into dozens of times, which complicates the problem of maintaining the optimum gas flow rate. The disadvantage of this method, as well as other technical solutions, in which the reactive gas is passed through the gas distribution grid or mesh at the reaction temperature, is the fact that these structural elements of the reactor over time acquire carbon deposits that require periodic cleaning of the reactor.

There is a method of producing carbon nanomaterials, in which the catalyst particles together with growing on them particles of the carbon nanomaterial is moved on the inclined surface of the substrate from the loading zone of the catalyst to the discharge area of the carbon nanomaterial under the action of vibration. This oscillatory motion is attached to the substrate, which is the inner surface of the reactor, made in the form of an inclined pipe [5] Cancers EG Methods of continuous production of carbon nanofibers and nanotubes // Chemical technology, 2003, No. 10, pp.2-7. This method provides a continuous process for the production of carbon nanomaterial.

The disadvantage of this method is the inefficiency of energy transfer to the vibrational motion of the part of the am of the catalyst and the carbon nanomaterial, the mass is small compared with the mass elements of the reactor, to which is supplied the energy of vibrational motion. In addition, this solution decreases the reliability of the reactor and its structural elements, vibrating at a high temperature, and also increases the likelihood of breakage of assistive devices, which to some extent also feel the vibration. Complicated by the seal of the reactor and its individual nodes.

There is a method of producing carbon nanomaterials, in which solid catalyst particles and particles of growing nanotubes are maintained in fluidized condition by vibration of the container, in which the catalyst and growing carbon nanotubes [6] Tkachev A.G., Zolotukhin I. Apparatus and methods for the synthesis of solid-state nanostructures. Moscow, Publishing house engineering-1", 2007. - 316 S. - Section 6.2. [7] S.V. Mishchenko, Tkachev A.G. Carbon nanomaterials. Production, properties, applications. - M.: "engineering", 2008. - 320 S. - Section 2.2. The consumption of gas components can be adjusted in an optimal way, based on the velocity of the flowing reaction, and does not depend on the constraints of maintaining a fluidized bed. In various embodiments, the implementation of this method, the gas mixture can be fed to the reactor che is ez gas distribution grid, as in the conventional method, fluidized bed, or through pipes or channels that are included in the bottom zone of the fluidized bed.

The advantage of the method vibramicina layer is no limit on the maximum speed of the gas flow, which allows to choose the optimal feed rate of the gas components, based on the speed of chemical reactions. The advantage is that in some versions it is possible to do without the gas distribution grid, introducing gas through pipes or channels in the bottom zone of the fluidized bed, in spite of the local introduction of gases, which ensures good mixing of the reaction mixture.

The disadvantage of this method is the fact that bringing a massive reactor or container in an oscillatory motion (vibration) requires a great expenditure of energy. The mass of the reaction layer, typically hundreds of times less than the mass of the oscillating structures, so that the efficiency of energy transfer to the vibrational motion of the catalyst particles and the carbon nanomaterial is extremely small. In addition, this solution dramatically reduces the reliability of the reactor, requires special vibration-proof performance of the structural elements of the reactor and auxiliary devices, increases the likelihood floors and structural members, creates problems with the sealing of the reactor. In addition, the vibration of the reaction mixture leads to the segregation of light and heavy particles, it is possible stratification of the reaction mass. In addition, under the action of vibration may seal the product that affects its properties.

There is also known a method of producing carbon nanomaterials described in [6, 7]. The catalyst is periodically loaded into the form of a fixed layer on the working surface of the reactor capacitive type, in which the temperature required for the growth of carbon nanomaterials. Later in the reactor gas serves as a source of carbon (e.g., propane-butane). After completion of the synthesis reactor is rinsed with an inert gas, the product (carbon nanomaterial) unloaded into the receiving hole of the hopper by means of the spiral scraper, next technological cycle is repeated specified number of times.

The advantage of this method is simplicity of design, the lack of entrainment of catalyst and carbon product in the form of dust from the gas stream, the absence of moving inside the reactor design elements for which critical fouling carbon.

The disadvantages of this method is, first, that the irrational use of the digester volume. The growth process of the carbon nanomaterial is in a relatively thin layer catalysis is the Torah, while the volume of the reactor is large enough. Secondly, due to the slow diffusion of gases in the layer of catalyst particles and growing the carbon nanomaterial layer thickness necessary to limit to ensure access of gas throughout the entire layer thickness. This reduces the performance of the reactor and leads to heterogeneity of the product formed in the top and bottom of the layer.

Known also adopted for the prototype method for producing carbon nanomaterials described in European patent EP No. 1790613, IPC C01B 31/02, 2007. The method includes loading into the reactor a solid dispersion of the catalyst, the inlet gases in the reactor, contacting the gases with the catalyst particles at a temperature synthesis of carbon nanomaterial, the release of gases from the reactor, and the catalyst was fed into the reactor periodically due to which the load of each subsequent portion of the catalyst is performed on the layer of growing carbon nanomaterials.

The known method is characterized by the complexity of instrumental performance, in the catalytic pyrolysis reactor made of quartz tube, it is difficult to achieve uniform distribution of the catalyst. This leads to poor performance of the reactor during the production of carbon nanomaterials.

The present invention is the task by changing the physical parameter the gas environment, to eliminate the above mentioned disadvantages of the prototype method.

The problem is solved because, according to the method of producing carbon nanomaterials, including loading in the reactor, a solid dispersion of the catalyst, the inlet gases in the reactor, contacting the gases with the catalyst particles at a temperature synthesis of carbon nanomaterial, the release of gases from the reactor and discharging the carbon nanomaterial from the reactor, and the catalyst was fed into the reactor periodically, due to which the load of each subsequent portion of the catalyst is performed on the layer of growing carbon nanomaterials, according to the invention in the reactor to create a variable pressure gas environment, the inlet gases is carried out at a pressure in the reactor, and release when the pressure decrease in the reactor, and the stage of the intake gases in the reactor and the release of gases from the reactor is repeated periodically, and discharging the carbon nanomaterial from the reactor is produced by re-periodic lowering the pressure of the gas medium in the lower part of the layer of the carbon nanomaterial.

Discharging the carbon nanomaterial from the reactor produced through the lock chamber, in which repeated periodically create a vacuum.

The following describes specific embodiments of the claimed method of producing carbon nanomaterials.

Example 1

Paul is an increase in the carbon nanomaterial is carried out in the reactor, shown schematically in figure 1. With the help of the furnace 1 in the reactor, maintain the temperature required for the synthesis of carbon nanomaterials (CNM). Typically, when used as a carbon source hydrocarbons optimum temperature synthesis CNM is 600-900°C. Case 2 reactor in the upper part is cylindrical, it narrows down on the cone. Through the pipe 3 into the reactor serves gases, and through the pipe 4 from the reactor output gases. Through the pipe 5, provided in the lower part of the dispenser flow in the reactor serves powder catalyst in the form of an aerosol in an inert gas or in the working gas mixture containing hydrocarbons. The flow of catalyst can be carried out both continuously and periodically recurring pulses. Devices used for aerosol and air transportation of powdery substances known in the art and there is no need to consider them in detail. Inside the reactor there is a layer of CNM. Unloading CNM from the reactor produced using the unloading device 6, which may be any known device that provides moving powdered material, for example, auger, conveyor belt, various pneumatic devices known in the art. The finished product is placed in the hopper 7. To eliminate contact CNM with air, and fixed what I diffusion of exhaust gases into the hopper (which can lead to contamination of ready CNM adsorbed hydrocarbons), through pipe 8 to produce the boost a weak flow of inert gas (argon, nitrogen). The process of obtaining CNM carried out as follows. Initially charged to the reactor to above the conical part of the reactor vessel prior CNM, made by any known method. Further, after the optimum temperature, the powdered catalyst loaded into the reactor continuously or periodic pulses, and the catalyst particles are deposited on the surface layer of the growing carbon nanomaterial. The stationary level of the layer of carbon nanomaterial control with level sensor (not shown), which may act on any physical principle, for example, measuring the capacity of insulated conductor, or measuring the parameters of the microwave field generated by the upper part of the reactor. Such sensors are known in the art. Unloading CNM is produced from the bottom of the layer CNM using auger with such a rate as to maintain a given fixed level of the layer of the carbon nanomaterial. Unloading CNM, as well as the catalyst loading can be made either continuously or periodically recurring pulses (portions). Flow of gases into the reactor through pipe 3 produce when the pressure of the gas environment in the reactor, which is achieved by overlapping in this Premiata the time of the outlet pipe 4. Since the volume of the hopper, which is connected to the reactor, much more free volume in the reactor above the layer of the carbon nanomaterial, rather a very small pressure increase above the layer that the components of the gas medium has penetrated into the layer of the carbon nanomaterial in sufficient depth. This is achieved by increasing the effective volume in which the growth of the particles of the carbon nanomaterial. Then the inlet 3 overlap and make the release of the gas mixture through the pipe 4. When this pressure falls, the gaseous reaction products out of the depth of a layer of carbon nanomaterial and out of the reactor. The cycles of intake and exhaust gas, accompanied by an increase and decrease the pressure of the gas environment in the reactor, repeat periodically. However, the duration of one cycle is selected based on the known laws of growth of carbon nanomaterials. Duration cycles of raising and lowering the pressure may be from several seconds to several minutes. The optimal duration of cycles can be selected on the basis of known data on the kinetics of growth of carbon nanomaterials using a specific catalyst and hydrocarbon. The pressure needed to penetrate components of the gas environment in the depth of the layer of catalyst, can the t can be calculated from the elementary laws of physics, knowing the volume of the reactor and the hopper, the cross-sectional area and thickness of the carbon nanomaterial, in which it is necessary to ensure the penetration of the components of the gas environment. Changing the volume of the tank or any tank connected to the reactor, it is possible thereby to set the desired pressure in the cycle of intake gas into the reactor. Practically these options, it is advisable to choose so that the maximum value (in the cycle of pressure increase), the excess pressure in the reactor was in the range of 0.001 to 0.01 MPa.

An example of the calculation. The diameter of the cylindrical part of the reactor is 0.6 m, the stationary level of the layer of the carbon nanomaterial is at a distance of 0.6 m from the ceiling of the reactor, hence the amount of free space above the layer of carbon nanomaterial 0,170 m3. Let the volume of the hopper together with the conical part of the reactor is 2 m3. You want to ensure penetration of the components of the gas among the layer of the carbon nanomaterial to a depth of 0.2 m from the surface layer.

Calculation (approximate). Layer volume CNM, in which there is contact with components of the gas environment is (diameter of 0.6 m, height 0.2 m) 0,0565 m3. Since the volume of the hopper together with the bottom part of the reactor is much greater than the volume of a layer of carbon nanomaterial, approximately can be considered that the reactor neo who should be let 0,0565 m 3gas at the temperature of the process (for example, 700°C), which is 0,0159 m3cold gas under normal conditions. The increase in the pressure in the entire system reactor + bunker will be{0,0565/(2+0,0565+0,170)}·1 ATM=0,025 bar=0,0025 MPa. This increase in pressure, even in re-periodic mode, has absolutely no influence on the service life of the structures of the reactor.

Thus, the claimed invention allows the growth of carbon nanomaterial with the layer thickness of the carbon nanomaterial, in this example, 0.2 m, which is impossible according to the method of the prototype with a layer of catalyst at constant pressure of the gas environment.

An additional advantage of the proposed method in comparison with other known technical solution is that it eliminates the entrainment of the dispersed particles from gases. So, for the fluidized bed due to intensive mixing and collision of particles form very fine particles of the catalyst and the carbon nanomaterial, which are carried away from the reactor by the gas flow. In the present the invention, the surface layer of the growing carbon nanomaterials are not mixed. As shown by numerous experiments, in terms of the fixed layer of particles of carbon nanomaterial intertwined in a loose agglomerate, which is almost not pilit in which the Otok gas.

Example 2

Production of carbon nanomaterial is carried out in the reactor, shown schematically in figure 2. With the help of the furnace 1 in the reactor, maintain the temperature required for the synthesis of carbon nanomaterials (CNM). Typically, when used as a carbon source hydrocarbons optimum temperature synthesis CNM is 600-900°C. Case 2 reactor in the upper part is cylindrical, it narrows down on the cone. Through the pipe 3 into the reactor serves gases, and through the pipe 4 from the reactor output gases. Through the pipe 5, provided in the lower part of the dispenser flow in the reactor serves powder catalyst in the form of an aerosol in an inert gas or in the working gas mixture containing hydrocarbons. The flow of catalyst can be carried out both continuously and periodically recurring pulses. Devices used for aerosol and air transportation of powdery substances known in the art and there is no need to consider them in detail. The exhaust gases from the reactor through a mesh segment 9, located below the steady state level of the layer of the carbon nanomaterial. Thus, the incoming gas passes through the layer of carbon nanomaterial, and in this volume, there is the growth of particles CNM. Due to the relatively large thickness of the active layer CNM reaches the I high compared with the method of the prototype performance of the process. Next, the exhaust gases pass between the walls and out of the reactor through pipe 4. Unloading CNM from the reactor is performed using a device for unloading 6, including the lock chamber 10, the upper cover 11 and lower cover 12 and valve 13. Unloading CNM in the hopper 7 is carried out by lowering the pressure in the lower part of the layer of carbon nanomaterial through the lock chamber 10, in which periodically generate the vacuum. Unloading is carried out again periodically. To do this periodically in the air lock chamber 10 to create a vacuum. At the moment of unloading lock chamber is disconnected from the vacuum line valve 13. Thus the output from the reactor is sealed by a top cover 11 and lower cover 12, which separates the lock chamber 10 from the hopper 7, also hermetically closed. The lower cover 12 is closed in the period between unloading of product to be fed to the reactor gas was not in the lock chamber 10 and then into the hopper 7. Because these caps are at a temperature not exceeding 100-200°C, ensuring the tightness is not an issue. For example, can be applied silicone rubber seals. After detaching the lock chamber 7 from the vacuum line valve 8 open the top cover 11. At the same time for a short time shutting off the gas supply to the reactor, to prevent leaks of hydrocarbons in the lock chamber 10 and further into the bunker PI in the lock chamber 7 of the reactor 2 is sucked some of the carbon nanomaterial, which quickly cools, because, as a rule, has a low bulk density. Next, the upper cover 11 is closed, open the bottom cover 12 and the material is poured into the hopper 7. In order to prevent diffusion of exhaust gases into the lock chamber 10 and into the hopper 7 which can lead to contamination of ready CNM adsorbed hydrocarbons), through the pipe 8 to produce positive pressure low flow of inert gas (argon, nitrogen).

Thus, by using pulses of negative pressure (vacuum) to produce periodic unloading of the carbon nanomaterial from the reactor. In this case, the catalyst loading can be carried out both continuously and repeated periodically, depending on a threshold level fluctuations of the surface layer of the carbon nanomaterial. The frequency and amount of paged for one pulse of the carbon nanomaterial adjusted so as to maintain within the specified limits of the stationary level of the layer of the carbon nanomaterial in the reactor. The stationary level of the layer of carbon nanomaterial control with level sensor (figure not shown), which may act on any physical principle, for example, measuring the capacity of insulated conductor, or measuring the parameters of the microwave field generated by the upper part of the reactor. Such sensors are known in the art.

Considered in example 2, a variant implementation of the proposed method provides a process for the production of carbon nanomaterial in quasi-continuous mode. Due to the fact that the growth process of the carbon nanomaterial is in a fairly thick layer defined by the height of the layer of material over the net, to achieve high performance in comparison with the prototype. Compared with other known technical solutions, for example, pseudoainhum layer, the advantage of the proposed method is the lack of entrainment of solid particles from the reactor with the gas stream. When this net segment 9, through which exhaust gases from the layer of the carbon nanomaterial, is cleaned periodically by pulses of negative pressure that it eliminates clogging. In the hot zone of the reactor contains no moving mechanical parts, which increases reliability and durability of the reactor.

Possible embodiments of the claimed invention is not limited to the given examples. So, the possible combination of examples 1 and 2, in which the penetration of the components of the gas environment in the depth of the layer of the carbon nanomaterial is achieved by re-periodic increase and decrease the pressure in the reactor, as in example 1, and the discharge of carbon nanomaterial from the reactor implementation of tlaut not auger, as in example 1, and the pulses of vacuum as in example 2. In this embodiment, the lid airlock in the periods of time between unloading of product is constantly open, unlike in example 2.

The invention can find application for the industrial production of carbon nanomaterials, particularly carbon nanotubes.

1. Method of producing carbon nanomaterials, including loading in the reactor, a solid dispersion of the catalyst, the inlet gases in the reactor, contacting the gases with the catalyst particles at a temperature synthesis of carbon nanomaterial, the release of gases from the reactor and discharging the carbon nanomaterial from the reactor, and the catalyst was fed into the reactor periodically, due to which the load of each subsequent portion of the catalyst is performed on the layer of growing carbon nanomaterials, characterized in that the reactor creates a variable pressure gas environment, the inlet gases is carried out at a pressure in the reactor and the exhaust at low pressure in the reactor, and the stage of the intake gases in the reactor and gases from the reactor is repeated periodically, and discharging the carbon nanomaterial from the reactor is produced by re-periodic lowering the pressure of the gas medium in the lower part of the layer of the carbon nanomaterial.

2. The method according to claim 1, characterized t is m, that the discharge of the carbon nanomaterial from the reactor produced through the lock chamber, in which repeated periodically create a vacuum.



 

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4 cl, 1 dwg, 2 ex

FIELD: process engineering.

SUBSTANCE: invention relates to power metallurgy, particularly, to production of metallic nano-sized powders.Initial powder of metal oxide compounds with particle size not exceeding 50 mcm is fed by carrier gas into reactor of gas discharge plasma. Initial material is heated to temperature exceeding that of oxides sublimation to evaporate metal and to reduce metal oxides in hydrogen flow or its mix with nitrogen or by argon. Metallic powder is isolated on cooling metal vapors by pulsating inert gas flow at gas flow rate of 1·10-6-1·10-3 m3/s.

EFFECT: ruled out or minimised agglomeration of condensed nano-sized pareticles.

7 cl, 3 ex

FIELD: process engineering.

SUBSTANCE: invention relates to physical chemistry and can be used for production of photon crystals with preset physical properties. Substrate with pre-applied silica microspheres is placed into reactor. Reactor chamber is evacuated to 10-4 torr. Substrate is heated to 192-230°C to feed precursor vapors at 45-56°C into reaction zone. Vapors are held for at least 1.5 s. Air is fed into reaction chamber to pressure of 10-2 torr. Reaction mix is held for, at least 2 seconds and reactor is evacuated to initial vacuum.

EFFECT: simplified process, expanded process performances due to production of preset size nanoparticles.

3 cl, 3 dwg

FIELD: medicine, pharmaceutics.

SUBSTANCE: group of inventions refers to medicine, particularly toxicology and radiology, to drug preparations based on antioxidant proteins and methods of using them. The pharmaceutical composition for treating toxic conditions wherein the therapeutic effect is ensured by the action of antioxidant, antimicrobial, antitoxic human lacroferrin protein on the human body contains non-replicating nanoparticles of human adenovirus serotype 5 genome with inserted human lactoferrin expressing human lactoferrin in the therapeutically effective amount in the body, and an expression buffer with the particle content not less than 2.33×1011 of physical particles per ml of the expressing buffer. The method of therapy involves administering the composition in the therapeutically effective dose of 7×1011 of physical particles to 7×1013 of physical particles per ml of the expressing buffer per an individual; the composition is administered intravenously.

EFFECT: invention provides the stable therapeutic effect after the single administration of the composition.

17 cl, 14 ex, 4 dwg

FIELD: metallurgy.

SUBSTANCE: ingot manufacturing method involves tempering of an ingot, multiple forging with series change of orientation axis through 90° at the temperature interval of 773-923 K with total true deformation degree of not less than 3 and further annealing at the temperature above isothermic forging temperature by 50 K during 1-5 hours.

EFFECT: obtaining an austenitic steel ingot with nanocrystalline structure and improved strength properties.

2 dwg, 1 ex

FIELD: chemistry.

SUBSTANCE: invention relates to cold curing epoxide compositions and can be used in making structures, including large-sized structures, from polymer composite materials by vacuum infusion in engineering fields. The epoxide composition includes an epoxide base containing epoxy-diane resin, an active diluent and a curing system based on an amine curing agent and a surfactant, characterised by that the epoxy-diane resin used is a resin or a mixture of resins with molecular weight 340-430, the active diluent used has viscosity of up to 0.1 Pa·s, the amine curing agent is a mixture of a curing agent basedd on an aromatic amine and a cold curing catalyst, and the curing system further includes a heterocyclic imidazole-type compound and a nanomodifier. The technical result is preparation of a high-technology epoxy composition, curable without the need for additional heat and without a large exothermic effect, and characterised by improved physical and mechanical properties.

EFFECT: composition is characterised by high modulus of elasticity of 3,8-4,2 GPa, which allows its use in making deformation-resistant articles from polymer composite materials with higher structural strength.

7 cl, 3 tbl, 12 ex

FIELD: chemistry.

SUBSTANCE: invention can be used in chemical industry. Cerium oxide CeO2 nanoparticles are obtained by mixing 0.2 M Ce(NO3)3 · 6H2O solution with supercritical water. The reaction is carried out at temperature of 370-390°C and pressure of 240-260 atm. The ratio of the volume of the cerium salt solution to the volume of supercritical water is preferably equal to 2:10.

EFFECT: synthesis of metal oxide nanoparticles and creating an ecologically clean, wasteless technology.

2 cl, 1 ex, 2 dwg

FIELD: chemistry.

SUBSTANCE: invention is meant for electronics and microelectronics and can be used in making coatings performing carrier transfer or storage functions, in transistors, electrodes, light sources, solar cells, field-emission cathodes, displays and sensors. The coating contains molecules of carbon nanobuds linked to each other by at least one fullerene group 2. Functional groups can be bonded to molecules of carbon nanobuds.

EFFECT: coating has on-off ratio greater than 1, which increases its stability, reduces the size of electric elements, increases their rate of operation and efficiency.

11 cl, 12 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to method of obtaining nanocomposites based on polyolefins, used in obtaining different products, such as films, sheets, tubes, threads and fibres. Carbon nanotubes are preliminarily ground in water with addition of water-soluble polymer with concentration 0.01-0.1 wt %. After that, suspension is dispersed by ultrasound at maximal medium temperature not higher than 70° C. After that, suspension is applied on the surface of polyolefic granules and dried. Obtained granules of nanocomposite contain to 0.5 wt % of carbon tubes.

EFFECT: nanocomposite materials possess high volumetric and superficial electroconductivity, heat-conductivity and high rigidity, with simultaneous increase of tensile modulus of elasticity to 50%, and limit of tensile strength to 30%.

3 cl, 4 dwg, 3 tbl

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