Laboratory line of production and research of carbon fibres
FIELD: technological processes.
SUBSTANCE: line includes two interconnected independent units: a thermal chamber for oxidative thermostabilization of polymer fibres up to 300°C, a through furnace for treatment of oxidized polymer fibres from 800 to 3200°C and an aggregate for possible finishing of the carbon fibre produced. The thermal chamber unit contains a thermostatically controlled sealed thermal chamber 1 with a temperature control system configured to control the temperature of the walls and the supply air according to a predetermined program in an automatic mode, a system 4 of fibre feeding, receiving and holding, equipped with a worm gear, a heated air supply system including an air pump 3 and a heater 2, a fibre tension measuring system comprising of a device 6 for fixing the deformation changes in the fibre, a roller 7 and a weight 8 for creating the required load. The through furnace unit of the oxidized polymer fibre heat treatment includes a heat treatment furnace body, divided into a precarbonization furnace 9 and a carbonization furnace 10, hermetically connected to each other, a system for fixing and controlling the temperature in the furnace, a system for removing and neutralizing the thermal destruction gases, a fibre feeding system containing a creel 11 and seven-rolls 13, a system for receiving fibre from the furnace, including the seven-rolls 13 and a receiving-winding device 12, a roll speed control system, a tension force measuring system and an inert gas supply system including a container 15. The apparatus for finishing the produced carbon fibre comprises of an impregnating bath 19, three-rolls 18 and a drying oven 20.
EFFECT: study of the mechanism of thermostabilization, carbonization and graphitization, improvement of fibre characteristics.
5 cl, 6 dwg
SUBSTANCE: proposed method consists in pinching of the cord between two clips, constant crosswise load being applied to cord centre, and in measuring the maximum sag. Pre-tensioning force F is calculated by the formula:
EFFECT: simplified procedure.
FIELD: machine building.
SUBSTANCE: hollow cylindrical post 7 rigidly secured on bed 1 to embrace turned-up cup flexible element 2 accommodates annular rest 8. Plate 11 is arranged under said rest. Plate top surface stays in contact with said rest 8. Plate bottom surface stays in contact with driving ball 10 arranged in recess 5 of flexible element barrel bottom 4. Detachable locating ring 12 is fitted on said rest 8 to accommodate additional driving ball 16. Through cutouts 13 are made at locating ring bed opposite ring generating line. Through holes 14 are made in hollow post 7 to be aligned with said cutouts 13 to receive rods 15 locking ball 16 in diametral plane perpendicular to device axis of symmetry.
EFFECT: higher accuracy of measurement.
1 tbl, 3 dwg
SUBSTANCE: formed fibres are subjected to thermal processing in an air medium with heating. The fibres with introduced carbon nanoparticles, which are represented by technical carbon in an amount of 0.2-10%, with the surface, containing oxygen in an amount not less than 4.8 atomic %, are subjected to oxidative stabilisation with an increase of temperature from 180 to 230°C at a rate of 0.5°C per minute for 90-110 minutes.
EFFECT: complete performance of the process of oxidative stabilisation of PAN fibres, filled with technical carbon, simplification of the technology due to reduction of the time of the process performance, with the simultaneous reduction of heat conductivity by the fibres, achieved due to the introduction of technical carbon into the fibres, which is necessary for further obtaining of a carbon material, used as a heat insulator for furnaces of an inert medium.
1 tbl, 5 ex
SUBSTANCE: invention relates to production of high-strength carbon bundles used to produce high-quality composites and a method of binding fibrous polyacrylonitrile (PAN) material when carrying out steps of producing carbon fibre therefrom. A method when carrying out steps which require process continuity when producing carbon fibre therefrom or producing express samples for processing phased modes and analysing a PAN precursor for suitability comprises binding short carbon fibres to a long PAN fibre with a braid consisting of two carbon fibres and one analysed fibre, such that the carbon fibre is an intermediate link between the PAN fibres, the length of the braid is not less than 100 mm with 3-4 weaves per cm.
EFFECT: high content of carbon fibres in the composite and maximum realisation of mechanical properties of the composite material.
SUBSTANCE: moulded fibres are subjected to heat treatment in an air medium while heating and maintaining a constant length. Content of carbon nanotubes in the fibres is 0.3-0.5%. The surface of the nanotubes contains oxygen in amount of not less than 3.5 at %. Oxidative stabilisation is carried out by raising temperature from 180°C to 230°C at a rate of 0.5°C per minute for 110-130 minutes.
EFFECT: simple technique owing to shorter process duration and improved strength properties of polyacrylonitrile fibres owing to low content of carbon nanotubes.
1 tbl, 7 ex
SUBSTANCE: method includes a spinning process, first drawing, drying and second drawing. Second drawing includes any process from (a)-(c): (a) drawing on air, where temperature of the thread from its point of separation on a hot roller to the point of first contact on the next roller is 130°C or higher, (b) drawing, where the distance from the point of separation of the thread on a hot roller to the point of its first contact on the next roller is equal to or less than 20 cm, (c) drawing in the drawing zone of a hot plate, where the hot plate is situated between two rollers, one of which is a heating roller which is mounted in front of the drawing zone of the hot plate, and the hot plate is placed such that the initial point of contact between the hot plate and the thread is at a distance of 30 cm or less from the point of separation of the thread on the heating roller, and the rotational speed of the heating roller is 100 m/min or more.
EFFECT: improved method.
10 cl, 8 dwg, 10 tbl, 57 ex
SUBSTANCE: polymer is soluble in a polar organic solvent and is modified in said solvent by an amine-based compound and an oxidising agent. The polymer has a structure which gives signals in the region of 150-200 h/million, determined via 13C-NMR, where the orientation of molecules according to measurement results obtained via wide-angle diffraction of X-ray radiation is 65% or higher, and specific weight is equal to or greater than 1.35.
EFFECT: fibre has high fire-resistance and strength retention value.
2 cl, 5 dwg, 30 ex
FIELD: machine building.
SUBSTANCE: chamber consists of working part of pass-through type for input and output of material, of directing shafts, of facilities for supply of oxidant and gas medium and for removal of pyrolysis product. Also, chamber consists of heating elements. The working part consists of successively connected sections in form of pressure tight interconnected central, inlet and outlet module sections with channels. Inlet and outlet module sections are pressure tight attached with their ends to inlet and outlet sluice boxes; a lower section is pressure tight isolated, while channels of the sections, except the second one from below, are closed on ends with gas gates.
EFFECT: intensification of treatment process, increased uniformity of fibres characteristics, safety and reduced power expenditures.
7 cl, 2 dwg
SUBSTANCE: stabilisation method involves putting carbonaceous fibre into a gaseous medium, its treatment with microwave radiation while simultaneously heating the gaseous medium. In a special case, the fibre is put into a working chamber containing a gaseous medium, heating the gaseous medium by heating the chamber (its walls) while simultaneously treating the fibre with microwave radiation. The method of producing carbon fibre involves at least a stabilisation step and carbonising the fibre. Precursor stabilisation is carried out using the method described above. The fibre can undergo further graphitation after carbonisation. Complex treatment with microwave radiation can be carried out while simultaneously heating the medium in which the fibre is put in order to carry out carbonisation/graphitation.
EFFECT: shorter time for stabilising precursor fibre, which results in low power consumption and high efficiency of the process of producing carbon fibre.
SUBSTANCE: starting material used is average-strength carbon fibre with linear density of 200-1600 tex and modulus of elasticity of 200-250 GPa. This fibre is twisted to 30-60 twists/m with finish agent content of more than 1%. The fibre is further finished with finishing agent content less than 1%. The twisted bundle undergoes primary thermal treatment at 2300-2500°C for 1-10 minutes until achieving at least 300 GPa modulus of elasticity of the carbon bundle. Second thermal treatment is carried out at temperature not lower than 3000°C for 1-20 s while pulling the bundle to 10% until modulus of elasticity of the carbon bundle increases to at least 450 GPa.
EFFECT: high quality is achieved owing to compact form of obtained carbon bundles, which ensures high content of carbon fibres in the composite material and maximum mechanical properties of the composite material.
FIELD: process engineering.
SUBSTANCE: invention relates to production of high-modulus carbon fibers made in PAN yarns used in fabrication of high-quality composites. In compliance with proposed method, initial PAN yarn with the number of filaments varying from 3K to 24K and made from copolymer containing at least 85% of PAN is subjected to preliminary twisting to 10 to 20 twist per metre and oxidised in air to density of 1.39 to 1.43 g/cm3. Then yarn is, again, subjected to twisting to 30 to 60 twist per metre and carbonised in two steps in neutral medium. First stage of carbonisation is performed at 2100°C to 2500°C till yarn elastic modulus of 300 GPa, while second stage is carried out at up to 3000°C.
EFFECT: avoiding entanglement of adjacent yarns, producing high-quality carbon yarns of various linear density.
SUBSTANCE: invention concerns technique of high-strength, high-modulus carbon fibers receiving. Method includes oxidation of precursor and its further high-temperature processing under tension, providing fiber drawing out. Beforehand fiber-precursor is processed by microwave radiation. Then at the first stage of thermal treatment it is implemented oxidation of fibers in nonequilibrium low-temperature plasma till receiving of fibers with consistency value 1.38-1.43 g/cm3. At the second stage thermal treatment is implemented in inert atmosphere at pressure from 20 till 750 torr or in vacuum with pressure lower than 10-2 torr, at that oxidised fiber till 400-450°C. At the third stage fiber is heated till temperature 600-650°C. At the fourth stage of thermal treatment fiber is processed at temperature 1100-4500°C. Received high-strength, high-modulus carbon fibers allows strength 400-510 kg/mm2 and modulus of elasticity 39000-49000 kg/mm2.
EFFECT: it is provided continuity of fiber receiving that provides improving of productivity and energy consumption reduction at receiving of fiber.
4 cl, 2 tbl
SUBSTANCE: thermal cycler contains holder, made with possibility of holding bioreservoir filled with reaction mixture and liquid, which has smaller specific weight that reaction mixture, and does not mix with reaction mixture. Bioreservoir contains channel, in which reaction mixture moves. Thermal cycler also contains heating unit, made with possibility of heating liquid in the first part of channel, when bioreservoir is in holder, and drive unit, made with possibility of rotating holder and heating unit around rotation axis to switch between first position and second position. First position is such that first part of channel is located below second part of channel with respect to direction of gravity, when bioreservoir is in holder. Second position is such that said second part of channel is located below first part of channel with respect to direction of gravity, when bioreservoir is in holder. Drive unit is made with possibility of holding holder and heating unit in first position for first period of time and holding holder and heating unit in second position for second period of time.
EFFECT: facilitation of control over heating time period.
15 cl, 16 dwg
SUBSTANCE: apparatus for controlling temperature of a reaction mixture contained in a reaction vessel comprises: an infrared source for exposing the reaction vessel to radiation in order to heat the reaction mixture, a temperature sensor for measuring temperature, which is an indicator of temperature of the reaction mixture and a controller for controlling the radiation source in accordance with temperature of the reaction mixture in order to selectively heat the reaction mixture. The method of controlling temperature of the reaction mixture involves determining temperature of the reaction mixture using information obtained from the temperature sensor, controlling the radiation source which is designed to expose the reaction vessel to radiation with subsequent heating of the reaction mixture, wherein the radiation source is controlled by the controller in accordance with temperature of the reaction mixture, as a result of which said temperature is controlled.
EFFECT: improved control of temperature of reaction mixtures, enabling real-time analysis of a reaction taking place in a vessel and with sufficiently high efficiency.
20 cl, 12 dwg
SUBSTANCE: invention relates to a single-step method of producing acetaldehyde via oxidation of ethylene in the presence of aqueous catalyst solution consisting of copper chloride and palladium chloride solution, while maintaining circulation of the aqueous catalyst solution in a reactor with a recirculating loop consisting of a reactor and a fog trap, characterised by that the entire outer wall of the reactor with a recirculation loop is heat insulated and its part which is under pressure is made from material which is resistant to corrosion by the aqueous catalyst solution or from ordinary material which is not resistant to corrosion by the aqueous catalyst solution, wherein the inner wall of the reactor is coated with corrosion-stable material having sufficient thermal stability at reaction temperature.
EFFECT: use of the present method improves volume-time-output factors, thereby increasing efficiency of the apparatus.
7 cl, 1 dwg
SUBSTANCE: invention refers to two chamber thermoelectric thermostat. Thermostat contains semiconductor thermoelectric modules, two cooled compartments and heat exchanger, consisting of radiator, blown by fan air flow. Cooled compartments are located on both sides of heat exchanger which contains two isolated heat-eliminating channels represented by two radiators located with their ribs tops opposite each other and separated by isolation plate.
EFFECT: equal temperature in the chamber and precision of its maintaining and autonomous work of bith chambers and exclusion of heat and atmosphere vapor influence on efficiency of the device.
5 cl, 3 dwg
SUBSTANCE: device for liquid sample introduction into the fluid carrier flow running through a continuous flow tube having an outlet and a common inlet wherein there are introduced both a carrier flow, and a liquid sample; the device comprises a tank for continuous fluid carrier supply into the inlet; the tank is designed to maintain the constant fluid carrier level above the inlet and fluid connected with the continuous flow tube in such a manner that when used, the fluid carrier flow and liquid sample are absorbed through the continuous flow tube when the tank is under atmospheric pressure and when the fluid carrier represents a hydrophobic liquid, while the liquid samples represents water test. The method involves the use of the device described above, creation of fluid connection of the continuous flow tube inlet and the tank, introduction of the fluid carrier in the tank and introduction of the liquid sample in the fluid carrier; while the fluid carrier flow and liquid sample are absorbed through the continuous flow tube when the tank is under atmospheric pressure. Also the method can involve immersion of a liquid sample distributor in the fluid carrier which is contained in the tank, liquid sample distribution in the inlet and running of the distributed dosed liquid sample by the liquid sample distributor so to supply the distributed liquid sample into the inlet and to absorb it through the continuous flow tube. The fluid carrier flow and liquid sample are absorbed through the continuous flow tube when the tank is under atmospheric pressure. Also the group of inventions includes a continuous flow system which contains the device specified above, and a method of nucleic acid amplification in PCR or LCR format, with the use of specified system.
EFFECT: method improvement.
21 dwg, 4 ex, 8 cl
FIELD: chemical or physical laboratory apparatus.
SUBSTANCE: knife comprises handle, intermediate section, working plate, and electric heater. The electric heater is mounted inside the intermediate section made of a tube. The working plate is connected with the tube in block. The handle is made of a 12-cm cylinder made of a heat-resistant material..
EFFECT: enhanced efficiency.
2 cl, 3 dwg
FIELD: heat exchange apparatus.
SUBSTANCE: concentrator-evaporator comprises housing with control unit and unit for temperature control, heater, and funnel-shaped evaporating vessel made of evaporating cap provided with opening in its bottom and guiding cone. The detachable concentrate collector is pressed to the guiding cone with a pressing device. The outer transparent surface of the collector is provided with the pickup of the concentrate level. The heater is mounted on the outer surface of the evaporating cap which is provided with heater-fan provided with air duct. Heated air is supplied to the evaporating surface tangentially. The concentrator-evaporator has at least two evaporating caps.
EFFECT: reduced sizes and power consumption.