WO2023075648A1

WO2023075648A1 - Composite materials with a polymer matrix subjected to thermal aging and low-temperature carbonziation and method of producing same

Info

Publication number: WO2023075648A1
Application number: PCT/RU2022/050344
Authority: WO
Inventors: Андрей Александрович СТЕПАШКИН
Original assignee: Общество с ограниченной ответственностью "Эластокарб Технолоджис"
Priority date: 2021-11-01
Filing date: 2022-10-31
Publication date: 2023-05-04

Abstract

The invention relates to the field of creating polymeric and composite materials, and more particularly to a method of forming, in a composite material, a matrix based on a polymer subjected to thermal aging and low-temperature carbonization. The resulting composite materials can be used as an alternative to traditional heat-resistant polymeric materials and composites in the production of assemblies and parts of machines and appliances, and can also be used in pumping machinery, for manufacturing parts of friction assemblies, as materials for chemical equipment, in electrode assemblies in electrochemical cells, and in heat sinks for electronic devices. The technical result of the invention is the production of composite materials that are able to act as an alternative both to polymeric structural materials such as polysulphone, polyethersulphone, polyphenylene sulphide, polyether ether ketone and others, as well as to other structural materials such as, for example, graphite and metals, and have improved performance characteristics such as: an ultimate tensile strength of up to 100 Mpa, a compressive strength of up to 300 MPa, a density of from 0.4 to 12 g/cm3, a Brinell hardness, according to GOST 4670–91, of up to 400 MPa, a total porosity of from 2 to 90%, including an open porosity of from 0.1 to 60%, chemical stability in acids and bases within a range of pH 1-14, a mass change rate of not more than 1% over 30 days, an electrical conductivity of up to 40 S/cm, a thermal conductivity of up to 15 W/mK, an operational thermal resistance of up to 300°С, and the ability to operate under dry friction. A discreetly reinforced composite material contains a polymer matrix consisting of a thermally modified composite polymer and/or elastomer and, distributed in said polymer matrix, a functional and/or reinforcing filler and an auxiliary component, with the following ratio of components distributed in 100 pbw of polymer matrix: 1-1200 pbw functional and/or reinforcing filler, and 0.5-50 pbw auxiliary component.

Description

Composite materials with a polymer matrix subjected to thermal aging and low-temperature carbonization, and a method for their preparation

FIELD OF TECHNOLOGY

The invention relates to the field of technologies for the creation of polymeric and composite materials, and in particular to a method for forming a matrix in a composite material based on a polymer subjected to thermal aging and low-temperature carbonization. The obtained composite materials can replace traditional heat-resistant polymeric materials and composites in the production of units and parts of machines and devices, be used in pumping equipment, for the manufacture of parts for friction units, as materials for chemical equipment, in electrode blocks of electrochemical cells, in radiators of electronic devices.

BACKGROUND OF THE INVENTION

The use of polymeric materials in various industries is steadily increasing every year. This trend is due to a combination of low density, chemical and corrosion resistance with a complex of physical, mechanical, thermal, tribological and other operational properties, combined with the low cost of manufacturing products from polymers. The production of complex-shaped products using well-established practically waste-free technologies for processing polymers (extrusion, injection molding) can significantly reduce the cost of production. Composite materials with polymer matrices make it possible to achieve a level of properties that significantly exceeds the characteristics of pure unfilled polymers. The prospect of using polymers and composite materials based on them as an alternative to metal and ceramic materials in various industries initiates the active development of research in the field of creating such composites.

To date, one of the significant problems that limit the use of polymeric materials in technology is their low heat resistance, since most of the polymers and elastomers used have operating temperatures below 150–200°C, and the few existing high-temperature polymers, such as polyimides, polybenzimidazoles , polybenzothiazoles, phthalonitriles, are currently produced in small volumes, difficult to process, and have a high cost. Increasing the heat resistance of products made from mass-produced polymers and elastomers available on the market will significantly expand the scope of their application in engineering due to a more complete realizing their advantages, such as low price, light weight and high specific characteristics.

It is known that one of the methods for increasing the heat resistance of polymeric materials is controlled aging under the action of heat, oxygen, and ozone. In the process of aging, the properties of polymers change, for example, the values of destructive stresses change under various types of loading, the corresponding values of deformations, crack resistance, impact strength, etc. decrease.

It is known that changes in properties that occur during aging are due to the occurrence in polymers of competing reactions of degradation and crosslinking in polymer macromolecules. Destruction reactions lead to a decrease in the molecular weight of the material and deterioration of its characteristics. During polymer crosslinking reactions, adjacent macromolecules or parts of one macromolecule are crosslinked to form a three-dimensional network of bonds. As a result of such cross-linking, the structure of the material changes, its deformations decrease under various types of impact, and thermal stability increases. The use of this approach in engineering makes it possible to increase the heat resistance of various polymers by 5O...7O°C, while the limiting aging temperatures do not exceed 200...250°C.

It is known that when providing protection against oxidation, all-carbon matrices have the highest thermal stability, and carbon-carbon composite materials are capable of operating at temperatures up to 2800...3000°C. The main approaches to the preparation of such matrices are accelerated carbonization of polymeric binders that are stable up to temperatures of 900°C. The course of carbonization begins at temperatures of 180...200*C, with increasing speed, while in the temperature range of 400...550°C, the complete destruction of the polymer component occurs, and at higher temperatures, the structuring of the resulting carbon residue (semi-coke) begins with formation of continuous nets of carbon atoms.

A known method for manufacturing products of complex shape based on a hybrid composite matrix, disclosed in RU 2670869 C1, publ. 10/25/2018, prototype. A method for manufacturing a product of complex shape based on a hybrid composite matrix based on discrete solid materials, including the use of at least a reinforcing filler or fillers, as well as a vulcanizable elastomeric polymer, a vulcanizing agent, characterized in that it includes the following manufacturing steps, in which:

- first, the initial ingredients of the hybrid composite matrix are homogeneously mixed with a vulcanizable elastomeric polymer as a binder based on a carbon- and / or silicon-containing polymer, while the prepared primary elastomeric mixture is vulcanizable into an elastic preform, after vulcanization, it has an elongation at break of at least 30% and a strength of at least 0.3 MPa, the ratio between the filler / fillers and the vulcanizing agent, acting as discrete materials and forming the basis of the hybrid composite matrix, and the binder elastomeric polymer is selected within 30 .. .1200 May. shares by 00 May. proportions of an elastomeric binder polymer;

- further, workpieces are made from the initial elastomeric mixture to form the product workpiece;

- the workpiece is vulcanized according to the molded or moldless technology for the production of an elastomeric product, while the temperature of 390...480 K and the process duration of 5...50 minutes are set to achieve the properties of the vulcanizate corresponding to the parameters T70-T90 of the rheogram;

- an elastic vulcanized workpiece is subjected to curing by heat treatment in the temperature range of 470...700 K for 1... Shore "D".

The disadvantages of the above method are:

- The use of only elastomeric polymers vulcanized using a vulcanizing agent, which significantly limits the conditions for obtaining semi-finished products (temperature 390 ... 480 K and the duration of the process 5 ... further thermal aging of blanks:

- Restriction on the deformation characteristics of the vulcanized semi-finished product (the primary elastomeric mixture vulcanized into an elastic preform has an elongation at break of at least 30% after vulcanization);

- The inability to obtain materials with high porosity and hardness (limited with porosity not more than 2% and hardness within 30 ... 98 units Shore "D"), the inability to regulate the ratio between open and closed porosity in the materials obtained;

- Limiting the size of the fillers used (preferably less than 300 microns);

- The absence of controlled cooling of the obtained products, which significantly affects the level of internal stresses in them.

DISCLOSURE OF THE INVENTION

The objective of the claimed invention is the development of compositions (composition) of composite materials with high performance and a method for their production. The technical result of the invention is the production of composite materials capable of replacing both structural polymeric materials, such as polysulfone, polyethersulfone, polyphenylene sulfide, polyetheretherketone, etc., and other structural materials, such as graphite and metals, with improved performance characteristics, such as: tensile strength up to 100 MPa, compressive strength up to 300 MPa, density from 0.4 to 12 g/ ^cm3 , Brinell hardness according to GOST 4670-91 up to 400 MPa, total porosity from 2 to 90%, including open porosity from 0, 1 to 60%, chemical resistance in acids and alkalis, within pH 1 ... 14, - weight change over 30 days is not more than 1%, electrical conductivity up to 40 S/cm, thermal conductivity up to 15 W/mxK, operating heat resistance up to 300 °С, the ability to work under dry friction conditions.

The specified technical result is achieved due to the fact that the discretely reinforced composite material contains a polymer matrix of thermally modified polymer and/or elastomer and a functional and/or reinforcing filler and an auxiliary component distributed in the polymer matrix, with the following ratio distributed in 100 wt.h, polymer matrix of components, wt.h: functional and/or reinforcing filler - 1 ... 1200; auxiliary component - 0.5...50. As a reinforcing filler, at least one component is used, selected from the group: carbon fibers based on hydrated cellulose, carbon fibers based on polyacrylonitrile, pitch carbon fibers, basalt fibers, polyacrylonitrile fibers.

As a reinforcing filler, dispersed particles ranging in size from 10 nm to 0.5 mm are used, selected from the group: carbon black (soot), silicon oxide (white soot).

The polymer matrix contains at least one polymer selected from the group: organic, inorganic, and organoelement polymers polypropylenes, polybutylenes, polyphenylene oxides, polystyrenes, polyarylates, polyamides, polysiloxanes, and/or at least one elastomer selected from the group: butadiene, butadiene - styrene, butadiene-nitrile, isoprene, ethylene-propylene, propylene-oxide, silicone rubbers.

The polymer matrix contains phenol-formaldehyde resins, and/or petroleum and/or coal tar pitches or mixtures thereof, in a total amount of 0.1 to 50 wt.% of the initial polymer.

As an auxiliary component, cross-linking agents are used - dicumyl peroxide, benzoyl peroxide, octyl-phenol resole resins, butyl-phenol resole resins, octyl-phenol resole resins modified with bromine, agents controlling the course of thermal destruction processes - sodium tetraborate, phosphorus (V) oxide.

As a functional filler, at least one component is used, selected from the group: discrete particles of artificial or natural graphite, carbon nanotubes, thermally expanded intercalated graphite, graphene, fullerenes, mesophase carbon, silicon carbide, boron nitride, titanium nitride, shungite fillers, glass microspheres , ceramic microspheres, d-element powders.

The specified technical result is also achieved due to the fact that the method of obtaining the composite material disclosed above includes the following steps: a) drying of the initial components, including a polymer and/or elastomer, a functional and/or reinforcing filler and an auxiliary component; b) surface treatment of the original components, including polymer and/or elastomer, functional and/or reinforcing filler and auxiliary component; c) obtaining a homogeneous mixture by mixing the initial components; d) the formation of the workpiece using molded or moldless technology; e) vulcanization of the workpiece at a temperature of 12O...22O°C and a pressure of 0.1...10 MPa for 5...60 minutes or heat treatment at temperatures of 17O...22O°C for 1...12 hours, or radiation exposure with an exposure dose of 1...35 Mrad; f) heat treatment of the billet in a controlled gas environment, including heating the billet to a temperature of 280...550°C at a rate of 0.01...10°C/min; e) cooling the billet to room temperature, while the billet is cooled to a temperature of 80°C at a rate of 0.001 ... 2.5 ^° C / min.

In step a) vacuum drying can be carried out.

In step f), one or more isothermal exposures can be additionally carried out at a temperature of 240...500°C for 0.5...100 hours

Step f) can be carried out both in the free, unloaded state of the workpiece, and with pressure applied to the workpiece from 0.1 to 10 MPa.

Step f) can be carried out in a flowing gas atmosphere of an inert gas with a supply of 0.01 to 50 ml/min per 1 g of composite material, both with a static state of the furnace atmosphere and with its dynamic stirring. BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be better understood from the description, which is not restrictive and given with reference to the accompanying drawings, which show: Fig. 1 - Change in heat resistance of a material containing 400 wt.h. silicon carbide before and after thermal aging and low temperature carbonization.

Fig. 2 - Microstructure of vulcanized samples (a, b) - degree of filling 50 mass parts of SiC, (c, d) - degree of filling 450 mass parts of SiC, distributed in 100 mass.h. polymer matrix.

IMPLEMENTATION OF THE INVENTION

The claimed discretely reinforced composite material contains a polymer matrix of thermally modified polymer and/or elastomer and a functional and/or reinforcing filler and an auxiliary component distributed in the polymer matrix, in the following ratio distributed in 100 wt.h. polymer matrix of components, wt.h: functional and/or reinforcing filler - 1 ... 1200; auxiliary component - 0.5...50.

As a reinforcing filler, at least one component is used, selected from the group: carbon fibers based on hydrated cellulose, carbon fibers based on polyacrylonitrile, pitch carbon fibers, basalt fibers, polyacrylonitrile fibers. These carbon fibers have a length of 0.01 ... 100 mm.

The polymer matrix contains at least one polymer selected from the group: organic, inorganic, and organoelement polymers, polypropylenes, polybutylenes, polyphenylene oxides, polystyrenes, polyarylates, polyamides, polysiloxanes, and other polymers, and/or at least one elastomer selected from groups: butadiene, butadiene-styrene, butadiene-nitrile, isoprene, ethylene-propylene, propylene-oxide, silicone rubbers.

As an auxiliary component, cross-linking agents are used - dicumyl peroxide, benzoyl peroxide, octyl-phenol resole resins, butyl-phenol resole resins, bromine-modified octyl-phenol resole resins, agents that control the course of thermal degradation processes - sodium tetraborate, phosphorus (V) oxide - As a functional filler, at least one component with a particle size of 10 nm to 0.5 mm is used, selected from the group: discrete particles of artificial or natural graphite, carbon nanotubes, thermally expanded intercalated graphite, graphene, fullerenes, mesophase carbon, silicon carbide, boron nitride, titanium nitride, shungite fillers, glass microspheres, ceramic microspheres, powders of d-elements (Ti, V, Cr. Mn, Fe, Co, Cu, W, Mo, Zr, Nb, Hf, Ta, etc.), as well as their oxides, nitrides, carbides, borides.

The method for obtaining the composite material disclosed above includes the following steps.

At the first stage, the initial components are dried, including polymer and/or elastomer, functional and/or reinforcing and auxiliary components. Drying is carried out at a temperature of 50 ... 115 ° C for 0.5 ... 120 hours using various known drying devices, for example, drying cabinets, heating chambers, incl. vacuum, etc. Drying of the initial components makes it possible to reduce the amount of sorbed moisture and thus reduce the amount of oxygen in the system.

After drying, the surface treatment of said initial components is carried out. Surface treatment includes, if necessary, at least one of the following operations: desizing, surface activation, whiskering, subsizing, chemical cleaning, finishing of fibrous fillers, surface treatment of fillers, including chemical surface treatment using alkalis, acids, organic compounds, including including using organofunctional silanes. Surface treatment of fibrous fillers provides an optimal level of adhesive interaction, which makes it possible to provide the required level of physical and mechanical characteristics of the composite material - crack resistance and impact strength. Processing of dispersed fillers is aimed at obtaining functional groups on their surface that are capable of forming chemical bonds with macromolecules in the process of polymer crosslinking in order to achieve an optimal level of adhesive interaction for the formulation.

Then, after surface treatment, a homogeneous mixture is obtained by sequentially introducing a functional and/or reinforcing filler and an auxiliary component into the polymer matrix, followed by mixing the polymer matrix with the components introduced into it using standard devices: one- or two-screw extruders, rollers, closed-type rubber mixers. types, intermixes, dosing and mixing systems for liquid fillers and rubbers. After obtaining a homogeneous mixture, the workpiece is formed using molded or moldless technology. In molding technology, molding of the workpiece is carried out in a mold, for example, by casting the resulting homogeneous mixture into a mold. With shapeless technology, the shape of the product is given by the mouthpiece of the extruder, through which the molded product of the required shape exits and is subsequently cut to the required length.

Then, after molding the blank, the mold is fixed by vulcanizing the blank at a temperature of 120,..220 ° C and a pressure of 0.1 ... 10 MPa for 5 ... 60 minutes or heat treatment at temperatures of 170 ... 220 ° C within 1...12 hours or radiation exposure with an exposure dose of 1...35 Mrad.

After fixing the mold, the final heat treatment of the workpiece is carried out in a controlled gas environment (argon, nitrogen, air, etc.), which includes heating the workpiece to a temperature of 28O...55O°C at a rate of 0.01...10°C7 min and leading to thermal aging and low-temperature carbonization of the workpiece. To implement the final heat treatment, standard furnaces with a controlled gas atmosphere are used, equipped with control systems that ensure heating at specified rates for a specified time and ensure a given uniformity of the thermal field inside the furnace. Heat treatment is carried out in order to form the final structure and material properties of products. Heating is carried out in a flowing gas atmosphere in order to remove gaseous pyrolysis products from the reaction zone; argon, nitrogen, air, etc. can be used as gases to create a flowing atmosphere.

At the last stage, the workpiece is cooled to room temperature!, while up to temperature! 80°C, the workpiece is cooled at a rate of 0.001...2.5°C/min. As a result, the final product is obtained - the claimed composite material, which can be machined to give the final geometry of the products. Cooling is carried out by known methods, for example together with the furnace in which the heat treatment takes place, or in air after leaving the furnace, or in a separate cooling device.

Heat treatment', leading to the processes of thermal aging and low-temperature carbonization of the workpiece, is carried out at a variable heating rate of the workpiece to a temperature of 28O...55O°C at rates varying in the range of 0.01...10°C/min.

During heat treatment, leading to processes of thermal aging and low-temperature carbonization of the billet, one or more isothermal holding at a temperature of 240...500°C for 0.5...100 hours is additionally carried out. Heat treatment, leading to the processes of thermal aging and low-temperature carbonization of the workpiece, is carried out in a free, unloaded state of the workpiece or at pressure applied to the workpiece from 0.1 to 10 MPa.

Heat treatment, leading to the processes of thermal aging and low-temperature carbonization of the workpiece, is carried out, if necessary, in a flowing gas atmosphere of inert gas with a supply of 0.01 to 50 ml/min per 1 g of composite material or in a flowing gas atmosphere of inert gas with a supply from 0.01 to 50 ml/min per 1 g of composite material with dynamic stirring of the atmosphere in the oven.

Example

To obtain a composite material, nitrile butadiene rubber, silicon carbide, and dicumyl peroxide are used as initial components.

NBR was dried in a vacuum oven at 50°C for 6 hours, weight loss 0.6%

Silicon carbide is dried in an oven for 6 hours, at a temperature of 115°C, weight loss of 0.9%.

After drying the initial components, a homogeneous mixture is obtained. To do this, 100 wt.h. are added to the rubber mixing rollers. butadiene-nitrile rubber, and then sequentially add from the content of the specified rubber 300 wt.h. silicon carbide and 1 wt.h. dicumyl peroxide and the initial components are mixed at a ratio of shaft speeds of 1:1.25 for 40 minutes.

Then the workpiece is molded in the form of plates 210x290x4 mm, for this a homogeneous mixture is placed in a steel tooling and the elastomer blanks are vulcanized in a steel tooling at a temperature of 160°C for 20 minutes, on a vulcanization press at a constant mold closing force of 5 MPa.

The resulting plates are subjected to heat treatment in an inert atmosphere (argon) when heated from room temperature to temperature! 340°C at a rate of 10 to O.GS/min for 12 hours in a muffle ashing furnace. Heat treatment leads to thermal aging and low-temperature carbonization of the workpiece.

Next, the heat-treated billet is cooled to a temperature of 80°C at a rate of 0.25'C/min in the furnace, and then it is unloaded from the furnace and cooled to room temperature in air.

As a result, a composite material is obtained, the properties of which are presented in Table 1.

Example 2 Example 2 is similar to example 1, except that with stirring in 100 wt.h. butadiene-nitrile rubber add 1 wt.h. silicon carbide and 0.5 wt.h. 1,3 1,4-bis (tert-butylperoxyisopropyl) benzene (LUPEROX F 40 E). Vulcanization of the workpiece is carried out at a temperature of 120°C and a pressure of 0.1 MPa for 5 min; heat treatment leading to thermal aging and low-temperature carbonization of the workpiece is carried out up to a temperature of 340°C at a rate of 10 to 0.1°C/min for 8 hours; cooling the billet to a temperature of 80°C at a rate of 0.5 ^eC /min in a furnace,

Example 3

Example 3 is similar to example 1, except that with stirring in 100 wt.h. butadiene-nitrile rubber add 600 wt.h. silicon carbide and 2 wt.h. dicumyl peroxide, as well as 2 wt.h. P2O5. Vulcanization of the workpiece is carried out at a temperature of 170°C and a pressure of 5 MPa for 15 min; heat treatment leading to thermal aging and low-temperature carbonization of the workpiece is carried out up to a temperature of 400°C at a rate of 5 to 0.1'C/min for 10 hours; with isothermal exposure at a temperature of 320°C for 1 hour, cooling the billet to a temperature of 80°C at a rate of 0.6°C/min in the furnace.

Example 4

Example 4 is similar to example 1, except that with stirring in 100 wt.h, butadiene-nitrile rubber add 1200 wt.h. tungsten carbide and 0.5 parts by weight of dicumyl peroxide. Vulcanization of the workpiece is carried out at a temperature of 120°C and a pressure of 10 MPa for 60 min; heat treatment, leading to thermal aging and low-temperature carbonization of the workpiece, is carried out to a temperature of 550°C at a rate of 5 to 0,GS/min for 12 hours; cooling the billet to a temperature of 80°C at a rate of 0.GS/min in a furnace.

Example 5

Example 5 is similar to example 1, except that with stirring in 100 wt.h. butadiene-nitrile rubber add 60 wt.h. silicon carbide, 190 wt.h. crushed artificial graphite with a particle size of D50 = 35 μm, 40 wt.h. carbon fiber 50 mm long, 1 wt.h. multi-walled carbon nanotubes, 9 wt.h. carbon black brand P-234 and 1 wt.h. dicumyl peroxide. Nitrile butadiene rubber is dried in a vacuum oven at a temperature of 50°C, in within 6 hours, weight loss 0.6%; silicon carbide is dried in an oven for 6 hours at a temperature of 115°C, weight loss of 0.9%; crushed artificial graphite is dried in an oven for 6 hours at a temperature of 115°C, weight loss 1.7%; surface treatment of carbon fibers is carried out in a muffle furnace at a temperature of 400°C for 10 minutes in an air atmosphere to remove the sizing and moisture. Heat treatment leading to thermal aging and low-temperature carbonization of the billet is carried out up to a temperature of 360°C at a rate of 5 to 0.1°C/min for 8 hours.

As a result, a composite material is obtained, the properties of which are presented in table 1,

Example 6

Example 6 is similar to example 5, except that with stirring in 100 wt.h. butadiene-nitrile rubber add 290 wt.h. silicon carbide, 50 wt.h. crushed artificial graphite with a particle size of D50 = 71 μm, 9 wt.h. technical carbon brand P-234, 50 wt.h. carbon fiber 50 mm long, 1 wt.h. multi-walled carbon nanotubes, 10 wt.h. modified alkylphenol resin Eteztobond T 6000 and 5 wt.h. butyl-phenol resole resin Eiaztobond C 650. Vulcanization of the workpiece is carried out at a temperature of 170 ^C and a pressure of 5 MPa for 25 minutes; heat treatment leading to thermal aging and low-temperature carbonization of the workpiece is carried out to a temperature of 360°C at a rate of 5 to 0.01°C/min for 24 hours, cooling of the workpiece to a temperature of 80°C at a rate of 1.25°C/ min in the oven.

Example 7

Example 7 is similar to example 5, except that with stirring in 100 wt.h. butadiene-nitrile rubber add 0.25 wt.h. titanium nitride, 0.25 wt.h. natural graphite GL-1 with particle size D50 = 140 μm, 0.25 wt.h. carbon fiber 100 mm long, 0.25 wt.h. multi-walled carbon nanotubes brand "Taunit" and 5 wt.h. octyl-phenol resole resin SP 1045 N. Vulcanization of the workpiece is carried out at a temperature of 120°C and a pressure of 1 MPa for 50 min; heat treatment leading to thermal aging and low-temperature carbonization of the workpiece is carried out up to a temperature of 280°C at a rate of 10 to 0.33°C/min for 6 hours; cooling the billet to a temperature of 80°C at a rate of 0.25°C/min in the furnace.

As a result, a composite material is obtained, the properties of which are presented in the table.

Example § Example 8 is similar to example 5, except that with stirring in 100 wt.h. styrene-butadiene rubber add 850 wt.h. tungsten carbide, 25 wt.h. crushed artificial graphite with a particle size of D50 = 140 μm, 20 wt.h. carbon fiber 100 mm long, 5 wt.h. multi-walled carbon nanotubes and 2.5 wt.h. di(tert-butylperoxyisopropyl)benzene. Vulcanization of the workpiece is carried out at a temperature of 150°C and a pressure of 10 MPa for 60 min; heat treatment leading to thermal aging and low-temperature carbonization of the workpiece is carried out up to a temperature of 340'C at a rate of 10 to 0.33°C/min for 24 hours; cooling the billet to a temperature of 80°C at a rate of 0.001°C/min in a furnace.

Example 9

Example 9 is similar to example 1, except that with stirring in 100 wt.h. butadiene-nitrile rubber add 225 wt.h. dispersed shungite filler Karbosil T-20 with a particle size of D50 = 6 μm, 25 wt.h. carbon fiber 10 mm long, 50 wt.h. technical carbon brand P-234, 3 wt.h. octylphenol resole resin SP 1045 H.

The nitrile butadiene rubber was dried in a vacuum oven at 50° C. for 6 hours, weight loss 0.6%.

Shungite filler Karbosil T-20 is dried in an oven for 6 hours at a temperature of 115°C, weight loss 1.0%.

Surface treatment of carbon fibers is carried out in concentrated nitric acid at a temperature of 25°C for 12 hours, after which the fibers are dried in an oven for 6 hours at a temperature of 115°C, weight loss of 2.7%.

During thermal aging and low-temperature carbonization, heating is carried out to a temperature of 340°C at a rate of 5 to 0.33°C/min for 8 hours and isothermal exposure at a temperature of 340°C for 2 hours.

Example 10

Example 10 is similar to example 2, except that with stirring in 100 wt.h. a mixture of butadiene-nitrile rubber with low-temperature coal tar pitch, taken in a ratio of 90:10, add 200 wt.h. crushed artificial graphite with a particle size of D50 = 71 μm, 50 wt.h. technical carbon grade P-234, 150 wt.h. carbon fiber 50 mm long, 10 wt.h. modified alkylphenol resin Elaztobond T 6000, 5 wt.h. butyl-phenol resole resin Elaztobond C 650 and 1 wt.h. 1,3 1,4-bis(tert-butylperoxyisopropyl)benzene (LUPEROX F 40 E). NBR mixed with low temperature coal tar pitch was dried in a vacuum oven at 50 ^° C for 6 hours, weight loss 1.4%; crushed artificial graphite is dried in an oven for 6 hours at a temperature of 115°C, weight loss 1.7%; surface treatment of carbon fibers is carried out in a muffle furnace at a temperature of ZOSGS, for 40 minutes in an air atmosphere to remove the sizing and alagi. Vulcanization of the workpiece is carried out at a temperature of 120°C and a pressure of 2.5 MPa for 10 min; Heat treatment leading to thermal aging and low-temperature carbonization of the workpiece is carried out up to a temperature of 340 ^C at a rate of 10 to 0.1°C/min for 8 hours; cooling the billet to a temperature of 80°C at a rate of 0.25°C/min in the furnace.

Example 11 Example 11 is similar to example 6, except that while stirring in

100 wt.h. ethylene vinyl acetate brand lotader 3210 add 600 wt.h. basalt fibers 10 mm long, 10 wt.h. carbon black brand P-234 and 2.5 wt.h. sodium tetraborate. To fix the shape of the workpiece, instead of vulcanization, heat treatment is used at a temperature of 170°C for 6 hours. As a result, a composite material is obtained, the properties of which are presented in table 2.

Example 12

Example 2 is similar to example 4, except that with stirring in 100 wt.h ethylene vinyl acetate brand lotader 3210 add 1200 wt.h, basalt fibers and 0.5 wt.h. P2O5. To fix the shape of the workpiece, instead of vulcanization, heat treatment is carried out at a temperature of 170°C for 6 hours.

As a result, a composite material is obtained, the properties of which are presented in table 2.

Example 13 Example 13 is similar to example 2, except that instead of vulcanization, radiation crosslinking is carried out, which is carried out using an electron accelerator "Electronics ELU-6" with an energy of 6 MeV, a flux density of 10' ^and e/cm ² xs and an irradiation dose of 1 Mrad.

Example 14

Example 14 is similar to example 3, except that instead of vulcanization, radiation crosslinking is carried out, which is carried out using an accelerator electrons "Electronics ELU-6" with an energy of 6 MeV, a flux density of 10 ^th e/cm ² xs and an irradiation dose of 15 Mrad.

As a result, a composite material is obtained, the properties of which are presented in table 2,

Example 15

Example 15 is similar to example 4, except that instead of vulcanization, radiation crosslinking is carried out, which is carried out using an electron accelerator "Electronics ELU-6" with an energy of 6 MeV, a flux density of 10 ¹¹ e/cm ² *o and an irradiation dose of 35 Mrad.

Example 16

Example 16 is similar to example 2, except that instead of vulcanization, heat treatment is carried out at a temperature of 170°C.

Example 17

Example 17 is similar to example 3, except that instead of vulcanization, heat treatment is carried out at a temperature of 195°C.

Example 18

Example 18 is similar to example 4, except that instead of vulcanization, heat treatment is carried out at a temperature of 220°C.

Example 19

Example 19 is similar to example 10, except that with stirring in 100 wt.h. a mixture of butadiene-nitrile rubber with low-temperature coal tar pitch, taken in a ratio of 90:10, add 100 May hours of technical carbon grade P-234, 300 wt.h. polyacrylonitrile fibers, 10 wt.h. modified alkylphenol resin Eiaztobond T 6000, 5 wt.h. butyl-phenol resole resin Elaztobond C 650 and 2.5 wt.h. sodium tetraborate.

Example 20

Example 20 is similar to example 10, except that with stirring at 100 mao.h. mixtures of butadiene-nitrile rubber with low-temperature coal pitch, taken in a ratio of 90:10, add 300 wt.h. basalt fibers, 20 wt.h. modified alkylphenol resin Eiaztobond T 6000, 5 wt.h. butyl-phenol resole resin Eiaztobond C 650 and 2.5 wt.h. sodium tetraborate.

Example 21

Example 21 is similar to example 1, except that the processes of thermal aging and low-temperature carbonization are carried out with dynamic mixing of the atmosphere in the furnace (supplying air flow into the furnace using a fan).

The invention has been described above with reference to a specific embodiment. For specialists, other embodiments of the invention may be obvious, without changing its essence, as it is disclosed in the present description. Accordingly, the invention is to be considered limited in scope by the following claims only.

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SUBSTITUTE SHEET (RULE 26)

SUBSTITUTE SHEET (RULE 26)

SUBSTITUTE SHEET (RULE 26)

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SUBSTITUTE SHEET (RULE 26)

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SUBSTITUTE SHEET (RULE 26)

Claims

CLAIM

1. Discretely reinforced composite material containing a polymer matrix of a thermally modified polymer and/or elastomer and a functional and/or reinforcing filler and an auxiliary component distributed in the polymer matrix, in the following ratio distributed in 100 wt.h. polymer matrix of components, wt.h: functional and/or reinforcing filler - 1...1200; auxiliary component - 0.5...50.

2. A composite material according to claim 1, characterized in that at least one component selected from the group is used as a reinforcing filler: carbon fibers based on hydrated cellulose, carbon fibers based on polyacrylonitrile, pitch carbon fibers, basalt fibers, polyacrylonitrile fibers.

3. Composite material according to claim 1, characterized in that as a reinforcing filler, dispersed particles ranging in size from 10 nm to 0.5 mm are used, selected from the group: carbon black (soot), silicon oxide (white soot).

4. Composite material according to claim 1, characterized in that the polymer matrix contains at least one polymer selected from the group: organic, inorganic, and organoelement polymers - polypropylenes, polybutylenes, polyphenylene oxides, polystyrenes, polyarylates, polyamides, polysiloxanes, and / or at least one elastomer selected from the group: butadiene, styrene-butadiene, nitrile butadiene, isoprene, ethylene-propylene, propylene oxide, silicone rubbers.

5. Composite material according to claim 4, characterized in that the polymer matrix contains phenol-formaldehyde resins, and/or petroleum and/or coal tar pitches or mixtures thereof, in a total amount of 0.1 to 50 wt.% of the mass of the original polymer.

6. Composite material according to claim 1, characterized in that cross-linking agents are used as an auxiliary component - dicumyl peroxide, benzoyl peroxide, octyl-phenol resole resins, butyl-phenol resole resins, bromine-modified octyl-phenol resole resins, control agents the course of thermal destruction processes - sodium tetraborate, phosphorus (V) oxide.

7. Composite material according to claim 1, characterized in that at least one component selected from the group is used as a functional filler: discrete particles of artificial or natural graphite, carbon nanotubes, thermally expanded intercalated graphite, graphene, fullerenes, mesophase carbon, carbide silicon, boron nitride, titanium nitride, shungite

22 fillers, glass microspheres, ceramic microspheres, powders of cl-elements.

8. The method of obtaining a composite material according to any one of paragraphs.1-7, including the following steps: a) drying the original components, including polymer and/or elastomer, functional and/or reinforcing filler and auxiliary component; b) surface treatment of the original components, including polymer and/or elastomer, functional and/or reinforcing filler and auxiliary component; c) obtaining a homogeneous mixture by mixing the initial components; d) the formation of the workpiece using molded or moldless technology; e) vulcanization of the workpiece at a temperature of 12O...22O°C and a pressure of 0.1...10 MPa for 5...60 min or heat treatment at temperatures of 17O...22O°C for 1...12 hours or radiation exposure with an exposure dose of 1 ... 35 Mrad; f) heat treatment of the billet in a controlled gas environment, including heating the billet to a temperature of 280...550°C at a rate of 0.01...10°C/min; e) cooling the billet to room temperature, while the billet is cooled to a temperature of 80°C at a rate of 0.001...2.5°C/min;

9. Method according to claim 8, characterized in that in step a) vacuum drying is carried out.

10. The method according to claim 8, characterized in that at step f) one or more isothermal exposure is additionally carried out at a temperature of 240 ... 500 ° C for 0.5 ... 100 hours.

11. The method according to claim 8, characterized in that step f) is carried out in a free, unloaded state of the workpiece.

12. The method according to claim 8, characterized in that step f) is carried out with a pressure applied to the workpiece from 0.1 to 10 MPa.

13. The method according to claim 8, characterized in that step f) is carried out in a flowing gas atmosphere of an inert gas with a supply of 0.01 to 50 ml/min per 1 g of composite material.

14. The method according to claim 8, characterized in that step f) is carried out in a flowing gas atmosphere of an inert gas with a supply of 0.01 to 50 ml/min per 1 g of composite material with dynamic stirring of the atmosphere in an oven.