Fibre precursor for carbon fibres, carbon fibre and method of producing carbon fibre
SUBSTANCE: invention relates to fibre precursor for carbon fibres, carbon fibre and a method of its production. Fibre precursor of carbon fibre contains a polymer of general formula (1): (1), where Ar1 is an aryl group, expressed by any structural formulae (1)-(5), and Ar2 is an aryl group, expressed by structural formula (6) or (7), except a combination, where Ar1 is a group, expressed by structural formula (3), and Ar2 is a group, expressed by structural formula (6), and combination, where Ar1 is a group, expressed by structural formula (1), and Ar2 is a group, expressed by structural formula (6): .
EFFECT: technical result is obtaining carbon fibre with excellent mechanical strength without non-fusible treatment.
8 cl, 10 dwg, 1 tbl, 2 ex
SUBSTANCE: fibre from completely aromatic metatype polyamide, in fact, does not contain layered clayey mineral, and amount of solvent, remaining in fibre, constitutes 1.0 wt % and less counted per the weight of total fibre. Rupture strength of fibre is in the range from 4.5 to 6.0 cN/dtex. For this purpose components or conditions of coagulation bath are properly controlled to obtain dense coagulation state, which does not include structure "shell-core". Plastic stretching within specific degree is carried out with further provision of obtaining appropriate conditions of further stretching at heating.
EFFECT: invention relates to novel fibre from completely aromatic metatype polyamide, which is characterised by high limit of rupture strength and can inhibit coloration or change of colour at high temperatures with simultaneous preservation of hidden properties of fibre from completely aromatic metatype polyamide, such as heat resistance and flame retardation.
3 cl, 1 tbl, 5 ex
SUBSTANCE: invention relates to production of chemical fibres and a method of producing high-strength, high-modulus aramid fibres. The method includes wet or dry-and-wet moulding of a solution of an aromatic heterocyclic copolyamide with a para-structure in a water-amide settling bath, followed by plastification of by stretching to 120%, washing, two-step drying with brief immersion of the fibres between the drying steps into a composition with a hydrophobisation organosilicon liquid, followed by heat treatment and hot-stretching. The two-step drying includes preliminary drying of the fibres at 120-150°C to moisture content of 60-80% under tension of 1-5 cN/tex and final drying at 120-150°C to moisture content of 7.0-20% under tension of 0.1-0.3 cN/tex.
EFFECT: invention enables to obtain high-strength, high-modulus aramid fibres with an improved set of physical-mechanical and operational characteristics.
4 cl, 1 tbl, 8 ex
SUBSTANCE: invention relates to technology of obtaining filamentous threads from paraaromatic polyamide. Optically anisotropic aramide spinning solution is filtered through filter with passing holes inside spinneret device and extruded inside spinneret device through multitude of spinning plates and air clearance with drawing and collection in water coagulation bath. Spinning solution in spinneret device is supplied through means of hydraulic resistance to spinning passing holes. Means of hydraulic resistance is located closer to spinning passing holes than filter. Means of hydraulic resistance and filter are located at a distance from each other.
EFFECT: application of invention ensures prevention of filament breaking in the process of spinning and increase of fibre strength.
12 cl, 6 dwg, 1 ex
SUBSTANCE: method includes extrusion of, at least, 15 wt % acidic acid of aromatic polyamide through linearly located draw plate holes; passing thread the base through layer of non-coagulating flow medium into coagulating bath; passing thread cloth through spinning tube, injection of additional coagulating liquid near threads downward at angle from 15° to 75° with respect to threads at constant rate, constituting approximately 50-100% of the rate of threads, movement of supplied coagulating liquid down together with the base of threads through spinning tube into coagulating bath. Tube has elongated transverse section and contains, at least, two opposite sides, parallel to the base of threads, with the length of the sides being, at least, equal to the width of the base of threads. Coagulating liquid is injected through injector channel from any one side of spinning tube, parallel to the base of threads, where injector channel has, at least, the same width as the base of threads.
EFFECT: invention relates to technology of production of synthetic fibres, in particular, to production of multitude of highly strong, high-modulus threads from aromatic polyamide.
6 cl, 3 tbl, 3 ex
SUBSTANCE: method involves preparing a spinning solution containing, in an aprotic solvent, 20-25 wt % polyamide imide and 5-15 wt % organic compound selected from a group comprising benzotriazole, benzoimidazole and imidazole. A dry-and-wet method is used to form hollow fibre from said solution. The fibre is washed and dried. Subsequent heat treatment is carried out at temperature not higher than 360°C.
EFFECT: invention enables to obtain hollow fibre based on polyamide imide, having improved strength properties and selectivity with respect to separated gases - nitrogen and oxygen.
3 cl, 2 dwg, 1 tbl, 9 ex
SUBSTANCE: method of production involves synthesis of a copolyamide by low-temperature copolycondensation of a mixture of 5(6)-amino-2(4-aminophenyl)benzimidazole, para-phenylenediamine and terephthaloyl chloride in an amide solvent solution with addition of 2.5-4.5 wt % LiCl or CaCl2, moulding the obtained polycondensation solution, washing, drying, heat-treating and hot-stretching the obtained fibre. In one version, synthesis is carried out with addition into the reaction mass of a viscosity stabiliser in amount of 4-25 mol % of the mixture of diamines and excess terephthaloyl chloride in amount of 0.15-1.2 mol % of the mixture of diamines. In another version, the viscosity stabiliser is added in amount of 4-7.5 mol % of the mixture of diamines, and at the end of synthesis, terephthalic acid is added in amount of 0.15-1.2 mol % of the mixture of diamines and stirred until complete dissolution, and copolymer terminal groups are converted during heat treatment in an inert medium at temperature of 340-360°C. The result is obtaining an aramid fibre which is characterised by ultimate strength of 260 gf/tex or higher, initial modulus of elasticity of 16000 kgf/mm2 or higher, wherein the increase factor of strength of the fibre in microplastic is 1.6 or higher, and breaking stress is 620 kgf/mm2 or higher.
EFFECT: high ultimate strength and elasticity of the fibre.
10 cl, 1 tbl, 11 ex
SUBSTANCE: invention relates to the technology of producing moulded articles in form of fibres and threads made from a heterocyclic aromatic polyamide. Disclosed is a method of producing moulded articles from a heterocyclic aromatic polyamide, involving polycondensation of terephthaloyl chloride with a mixture of aminoimine 5(6)-amino-2(para-iminoquinone) benzamide, having melting point of 235±3°C, with aromatic diamine 5(6)-amino-2(para-aminophenyl) benzimidazole, having melting point of 216±3°C, with content of the latter of 5-60 wt % and para-phenylene diamine in amount of 0-30 wt %. The obtained polycondensation solution with dynamic viscosity of 300-800 P is homogenised, moulded into a settling aqueous-organic bath, washed, dried at temperature not higher than 120°C. The end products can be used to produce high-strength composite materials, articles operating under high loads, fabrics for making protective articles etc.
EFFECT: obtained articles have improved physical and mechanical properties (breaking tenacity, modulus of elasticity, breaking stress in microplastic) with low fluctuation of characteristics.
2 cl, 1 dwg, 5 tbl, 5 ex
FIELD: textiles, paper.
SUBSTANCE: invention relates to hollow fiber comprising a cavity located in the center of the hollow fiber, macropores located near the cavity, and mesopores and picopores located near macropores, and picopores are connected to each other in three dimensional space to form a three-dimensional net structure, and hollow fiber comprises polymer derived from polyimide, and polyimide comprises repeating structural unit derived from aromatic diamine comprising at least one functional group comprising OH, SH or NH2, which is in the ortho position in relation to the amino group, and dianhydride. Also the spinning solution composition for obtaining the above mentioned hollow fiber and method of producing the hollow fiber is described.
EFFECT: creation of hollow fibers having improved gas permeability and selectivity in relation to gases, creation of new membranes for separation of gases based on these materials.
48 cl, 18 ex, 1 tbl, 9 dwg
SUBSTANCE: aromatic polyamide fibres, containing a heterocycle-containing aromatic polyamide, undergoes thermal treatment in conditions with oxygen content of 1 vol. % or less after stretching. The aromatic polyamide fibres are characterised by tensile strength of 20 cN/dtex or higher, initial modulus of 500 cN/dtex or higher, and the amount of substance dissolved in sulphuric acid equal to or less than 45%.
EFFECT: disclosed heterocycle-containing aromatic polyamide fibres demonstrate an excellent balance between tensile strength, initial modulus and strength in a direction perpendicular the axis of the fibre, are characterised by high strength retention coefficient under heat and moisture conditions and excellent fire-resistance, bullet-proof properties and cutting resistance.
11 cl, 1 tbl, 12 ex
SUBSTANCE: fibre is obtained via wet spinning of a solution which contains poly-meta-phenyleneisophthalamide as the main component, and an amide solvent containing a salt in settling bath. The water coagulation bath contains 40-60% amide solvent and 0.3-10% salt. The obtained porous fibre is stretched 1.5-10 times in a stretch bath with aqueous 20-70% solution of amide solvent at 20-70°C and then washed with water. The fibre then undergoes thermal treatment in an atmosphere of saturated vapour at 0.02-0.5 MPa with stretch ratio of 0.7-5.0 and then undergoes dry thermal treatment at 250-400°C with stretch ratio of 0.7-4.0. The ready fibre contains 1.0% or residual solvent, a small amount of volatile substance which is dangerous at the step for thermal treatment at high temperature, and capable of preventing dyeing of the product made from the fibre. The degree of dry thermal setting at 300°C is equal to or less than 1.6% and breaking strength is equal to or more than 3.0 cN/decitex.
EFFECT: excellent high-temperature processability.
11 cl, 1 tbl, 6 ex
SUBSTANCE: first step includes obtaining low-hydroxylated insoluble fullerenols by reacting concentrated fullerene solution in o-xylene with aqueous ammonia solution in the presence of a tetrabutylammonium hydroxide phase-transfer catalyst at 35-40°C. At the second step, the obtained low-hydroxylated insoluble fullerenols are hydroxylated to transform them into a water-soluble form by mixing with 6-15% aqueous hydrogen peroxide solution and heating for 4-5 hours at 65°C. Water-soluble fullerenols are then precipitated from an alcohol-containing solution.
EFFECT: simplifying the method while preserving quality characteristics and full extraction of the end product.
2 cl, 1 dwg, 4 tbl, 3 ex
SUBSTANCE: invention can be used in obtaining coatings, reducing coefficient of secondary electronic emission, growing diamond films and glasses, elements, absorbing solar radiation. Colloidal solution of nano-sized carbon is obtained by supply of organic liquid - ethanol, into chamber with electrodes, injection of inert gas into inter-electrode space, formation of high-temperature plasma channel in gas bubbles, containing vapours of organic liquid. High-temperature plasma channel has the following parameters: temperature of heavy particles 4000-5000K, temperature of electrons 1.0-1.5 eV, concentration of charged particles (2-3)·1017 cm3, diameter of plasma channel hundreds of microns. After that, fast cooling within several microseconds is performed.
EFFECT: simplicity, possibility to obtain nanoparticles of different types.
3 cl, 1 dwg
FIELD: process engineering.
SUBSTANCE: invention relates to production of sealed articles for chemical industry and metallurgy. First, carcass of refractory fibre is made that features linear expansion factor approximating to that of the matrix material components. Then, carcass is compacted by carbon-bearing material to get the billet of porous carbon-bearing composite impregnated with ceramics-forming binder that makes a precursor of silicon nitride and/or carbide. Plastic billet is formed at binder solidification temperature and processed at its final temperature of 1300-1600°C. Then, carbon is introduced in material pores. Then, siliconising is performed by vapour-liquid-phase process at heating, holding and cooling in silicon vapours. For this capillary condensation of silicon vapours is conducted at 1300-1600°C and reactor pressure not over 36 mmHg followed by holding at 1600-1700°C for 1-2 hours. Finished article finished is cooled and withdrawn from the unit.
EFFECT: longer life.
4 cl, 1 tbl, 11 ex
SUBSTANCE: invention can be used in chemical industry. Natural or synthetic graphite or thermally expanded graphite contacts to oxygen or ozone at a temperature of -30°C to 700°C. The produced precursor representing a graphite material functionalised by oxygen groups (FOG) with molar ratio of carbon/oxygen more than 8:1 is reduced by chemical or physical aids. The chemical recovery involves using water gas, hydrogen, hydrazine, and methyl hydrazine. The physical recovery involves heating to at least 600°C at a temperature gradient of more than 10°C a minute. The molar ratio of carbon/oxygen in the prepared nanosized graphene plates is more than 20:1.
EFFECT: expandable thermoplastic polymer compound contains the thermoplastic polymer matrix; 1-10 wt % in relation to a polymer of the expanding agent; 0,004-15 wt % in relation to a polymer of the prepared nanosized graphene plates having high electric conductivity and dispersing ability in non-polar and low-polar polymers.
9 cl, 1 dwg, 11 ex
SUBSTANCE: invention relates to chemistry and nanotechnology. The method includes first preparing a solution of polyacrylonitrile (PAN) and acetyl acetonate Fe(CH3COCH=C(CH3)O)3·6H2O in dimethyl formamide at 40°C; adding cobalt acetate solution Co(CH3COO)2·4H2O to the dimethyl formamide; concentration of PAN is 5% of the weight of dimethyl formamide and concentration of iron and cobalt is 5-20% and 5-20% of the weight of PAN, respectively; holding the solution until complete dissolution of all components, followed by removal of dimethyl formamide by evaporation at temperature not higher than 70°C. The obtained solid residue is heated with high-intensity infrared radiation by holding for 15 minutes at 150°C-200°C and then for 10 minutes at final temperature of 600-800°C. Heating the solid residue at all steps is carried out at a rate of 20°C/min at pressure in the reaction chamber of 10-2-10-3 mmHg. The obtained metal-carbon nanocomposite FeCo/C contains FeCo nanoparticles with size of 5-50 nm.
EFFECT: avoiding the need to use additional reducing agents.
1 tbl, 3 dwg, 3 ex
SUBSTANCE: invention relates to chemical industry. A method of separating fullerenes includes dissolving fullerenes in o-xylene, high-temperature treatment of the obtained solution at 70-90°C for 60-120 minutes to obtain a C60 concentrate and a solution which is fed for low-temperature treatment at temperature of (-15) to (-25)°C for 10-30 hours. Separation is carried out in multiple steps to obtain at each n step C60 and C70 concentrates with counterflow of the solutions and the solid phase from the high-temperature treatment. Several high-temperature treatment steps are carried out at each n step. At the first high-temperature treatment step of each n step, a solid extract of a fullerene mixture is fed and at the next steps, a solid phase from the previous high-temperature treatment step is fed. A solution from the first high-temperature treatment step is fed for low-temperature treatment to obtain a C70 concentrate and a solution which is fed to the last high-temperature treatment step. A solution from the next high-temperature treatment step is fed as a recycled solution to the previous step, and a solution from the second high-temperature treatment step is fed for mixing with the solid extract of the fullerene mixture of the next n>1 step. The C60 concentrate is the solid phase of the last high-temperature treatment step of each n step.
EFFECT: low material consumption and simple process.
2 cl, 2 dwg, 1 tbl, 2 ex
SUBSTANCE: invention relates to apparatus for producing inorganic materials. The apparatus comprises a working chamber 1, which includes a high-temperature ionised medium 2 source and an inert gas 4 source, the housing of which has a cooling system in the form of a jacket 8 filled with a coolant, the cavity of the chamber 1 is linked with a container 3 of the starting inorganic powdered material - silicon or carbon, the working chamber 1 is fitted with a vacuum apparatus 5, and the cavity of the chamber 1 is fitted with a heat exchanger 8 for accumulating the processed starting material, connected to the source of a heat-exchange medium and mounted on one side of the working chamber 1, connected to the housing by a hinge 10.
EFFECT: obtaining materials with negligible power consumption when processing the starting component and high resistance to aggressive media.
SUBSTANCE: invention relates to chemistry and can be used in producing nanoelectronic, optoelectronic, sensor and photovoltaic devices, as well as for storing energy. The method includes depositing an aluminium film with thickness of 1-100 nm on an insulated substrate, sputtering thereon a film of a transition metal, e.g. Fe, Co or Ni, with thickness of 0.1-10 nm, annealing in air at temperature of 200-950°C for 0.1-10 min, heating to temperature of 700-1000°C in a reactor which is evacuated to pressure of 10-4-10-10 Torr. The method further includes successively releasing a carbon-containing gas to pressure of 1-10-4 Torr and evacuating the reactor every 1-30 s while simultaneously cooling to room temperature at a rate of 1-100°C/min.
EFFECT: invention enables to obtain films of hybrid graphene and carbon nanotubes with a given configuration at predetermined places using a simple and technologically effective method.
5 cl, 5 dwg, 5 ex
FIELD: medicine, pharmaceutics.
SUBSTANCE: invention can be used in the chemical industry, cosmetics and medicine in making cosmetic products, therapeutic agents, antioxidants, antimicrobial agents, radioprotective substances, compounds for gene material delivery. An aqueous nanodispersion of fullerene is produced by solving C60 fullerite crystals in N-methylpyrrolidone. The prepared solution is mixed with water and a stabilising agent, which is presented by amino acid, monosaccharide, peptide, polyvinylpyrrolidone or glycerol. That is followed by the dialysis of the prepared mixture. After the dialysis, the solution can be concentrated, e.g. by vacuum vaporisation. The process is safe as uses no toxic solvents.
EFFECT: simplifying the process by eliminating the use of pre-milled fulleren crystals, ultrasonic treatment and heating.
2 cl, 26 dwg, 4 ex
SUBSTANCE: carbon nanomaterials - nanotubes or graphene, particles of which contain hydroxyl and/or carboxyl groups on the surface are modified by treating with a solution containing triethanolamine titanate and fatty acid derivatives - triethanolamine stearate or triethanolamine palmitate. The molar ratio of said fatty acid derivative to titanium ranges from 1:1 to 3:1, and the weight ratio of said fatty acid derivative and titanium compounds with respect to titanium dioxide to nanotubes or graphene ranges from 0.75:1 to 2:1. The obtained suspension is treated with carbon dioxide gas until coagulation of the system and the precipitate is then washed with water.
EFFECT: obtained modified carbon nanomaterial disperses well in nonpolar media without using ultrasound.
2 cl, 1 tbl, 9 ex