Method for producing of thermally- and fire-resistant textile materials

FIELD: production of thermally- and fire-resistant textile materials, in particular, materials produced from mixture of thermally stable synthetic fiber and oxidized polyacrylonitrile fiber, which may be used for manufacture of protective clothing for rescuers, servicemen, firemen, oil industry workers, and gas industry workers, filtering fabrics for cleaning of hot gases from toxic dust in metallurgical, cement and other branches of industry, decorative materials, thermally-resistant isolation, and toxic asbestos substitutes.

SUBSTANCE: method involves mixing non-oxidized polyacrylonitrile fiber with thermally stable synthetic fiber in the ratio of from 30/70 to 80/20, respectively; subjecting resulting mixture in the form of yarn, tape, fabric to thermally oxidizing processing at temperature of 240-310 C during 10-180 min.

EFFECT: elimination of problems connected with textile processing of frangible oxidized polyacrylonitrile fibers owing to employment of elastic polyacrylonitrile fibers rather than such oxidized fibers.

2 cl, 7 tbl, 6 ex

 

The invention relates to a technology for termignoni textiles (yarn, cloth, tape, knitted fabrics, non-woven products) from a mixture of heat-resistant synthetic fibers and oxidized polyacrylonitrile (OPEN) fiber.

Armourstone textile materials from a mixture of heat-resistant synthetic and OPEN fibers can be used to produce various fire protective products, ensuring the safety of human life, protective clothing, rescue workers, military personnel, firefighters, oil and gas, filter cloth for cleaning hot gases from toxic dusts in the steel, cement and other industries, decorative and finishing materials for interior places and vehicles, heat-resistant electrical and thermal insulation, substitutes for toxic asbestos, etc.

At the present time in the world practice to create the most effective termignoni materials textile destination using heat-resistant synthetic fibers. Basically it methanamine (Nomex, konex, Carmel) and para-aramid (Kevlar, Twaron) fiber. Aramid fiber textile purposes, produced in industrial scale (several tens of thousands of tons per year, are very expensive materials. The cost per order is higher than normal rates of synthetic fibres, therefore, find application in textile materials from mixtures of heat-resistant fibers with conventional synthetic and natural fibers with a flame retardant impregnation last antipyrene. However, the fire retardant properties of such materials can vary during operation and practically does not remain after washing.

Relatively inexpensive and available thermogenetic fiber is a fiber-based oxidized polyacrylonitrile (OPEN), the starting product for the production of which is cheap polyacrylonitrile (PAN) fiber type Nitron. The advantage of OPEN fiber is a high degree of ognezashita (oxygen index 45-55% vs. 28-30% of aramids). Under various names (panox, Piron, pyramex, lastan and others) OPEN fibers are made of various foreign firms in the total number of the order of several thousand tons per year. They are widely advertised as the most accessible and affordable to use for the same purposes, and aramid fibers (the journal "Chemical fibres, 2003, No. 6, p.3-8). However, in the literature when describing the methods of preparation, properties and applications of OPEN fibers almost does not address the crucial question of the substantial difficulties of the textile processing of these fibers.

Difficulties arising during the processing of OPEN fibers in textiles, also decided the Lena not so much low strength fibers (16-22 CN/Tex), as argued, for example, in U.S. patent 6287686, 2001, as its fragility. The fragility of these fibers is not possible even to estimate their strength at break loop, as the fiber is destroyed when filling in the clamps of the bursting machine. It leads to the formation of large amounts of waste in the form of fragments of fibers and a decrease in strength of textile materials. Not by chance, therefore, patentable methods of co-processing of OPEN fibers with others, including heat-resistant aramid fibers (U.S. patent 4865906, 1989 and 6287686, 2001). The disadvantages of textile products from OPEN fiber is not only their low strength, but low resistance to abrasion.

In order to avoid difficulties processing OPEN fibers in textiles, the number of patents offered to get a first textile products (yarn, fabric) of POLYACRYLONITRILE fibres, which are then subjected to thermal-oxidative processing and subsequent heat treatment to obtain a carbon textile materials (SU 138324, 1966, SU 1835438, 1993). Thermal-oxidative treatment of polyacrylonitrile fiber or fabric made from it, SU 138324 carried out in air at temperatures between 120°to 200°C. And at 200°With fiber or fabric to withstand 25-30 hours. After this treatment, the fiber or cloth becomes black. the alley they are treated when 400-475° C for 1-1 .5 hours and fabric weighing 200 g/m2gets properties of the non-in the flame of the burner and satisfactory mechanical properties.

The method of obtaining carbon tissue on the basis of acrylic fibers, described in SU 1835438 involves the stages of thermal oxidation at 170-250°C for 4-6 hours and carbonization up to 1500-1800°when the tension of the warp and weft of the fabric. Fabric produced from different threads: PAN yarn with a linear density of 125 Tex on the basis of OPEN yarn in the weft, or, conversely, from OPEN threads in the base and PAN yarn in the weft. Therefore, the manufacture of such fabrics include weaving fragile OPEN threads presents certain difficulties. As the cloth for about half PAN threads have been moved into OPEN threads preliminary thermal-oxidative treatment, and thermal-oxidative treatment of the fabric is carried out at higher temperatures (170-250° (C) compared with tissues from one PAN threads, for which the temperature at the stage of thermal oxidation should not be above 200-220°that was not intensive gas in an isothermal process, thermal oxidation, and local overheating or ignition. Thus, thermal-oxidative treatment of tissue from one PAN fibers is carried out at temperatures of about 200°and long duration of the process from up to 30 hours.

In U.S. patent 4865908, 1989, claimed abrasion-resistant fire-resistant textile material such as felt or yarn, comprising OPEN fiber in a mixture of at least two other fibers selected from the following: polyvinyl chloride, polybenzimidazole, para-aramid, methanamine fiber of fire-protected polyester, fire-protected viscose fiber, fire protective coat, and OPEN fibers in the mixture contains from 25% to 85%, and if you are using para-aramid fiber, it is in the mixture should be no more than 35%. The mixture of fibers with the fibers of OPEN perform common in textile production methods, such as during drop-in cutting threads or through a mixture of bales of different fibers, combining beams of different fibers on the tape machine. The optimum content of OPEN fiber in composite textile material is about 70% to achieve a satisfactory abrasion resistance provided by other types of fibers, among which the best are Kevlar, Kevlar mixed with Nomex, fire protective coat.

However, the resistance of such materials is slightly reduced, remaining, however, is much higher fire resistance metaraminol fiber Nomex.

In U.S. patent 6287686, 2001, described armourstone textile materials based on fiber mixtures obtained what information and communications technology oxidized PAN fiber, the content of which in the mixture from 85.5% to 99.9%of at least one other fiber, providing increased strength and resistance to abrasion mixed products. For mixing use the following fibers: polybenzimidazole, polyparaphenylene-2,6-benzobisoxazole, para-aramid, methanamine, PVC, melamine, wool, fire-protected polyester, nylon, viscose, cotton.

However, as practice shows processing of mixtures containing OPEN fibres such palliative solutions do not resolve the difficulties of manufacture composite textile materials.

The technical result of the present invention is an improvement in textile processing mixtures of fibers with the production of finished textile products containing OPEN fiber. The desired result is achieved by using at the stage of mixing the fibers are not oxidized, and the original, elastic and easily recyclable acrylic fiber with its subsequent oxidation by heat treatment in air in the form of finished products (yarns, ribbons, fabrics), obtained in a mixture with a heat-resistant synthetic fibers at temperatures 240-310°and With duration from 10 to 180 minutes, and the mass ratio of heat-resistant fibers to polyacrylonitrile from 30/70 to 80/20.

This provides the tsya:

- ease of processing mixtures of fibers in textile materials;

- more ognezashita due to higher rates of OPEN fibers;

- the combination of the oxidation process of the PAN from the heat treatment process, for example, aramid fibers in order to give messagecast at elevated temperatures and significant hardening;

- staining materials in brown and black colors;

- a significant reduction termignoni textiles at the expense of the share of cheaper oxidized PAN.

Temperature range for the heat treatment in the air mixed textile materials in order to conduct the oxidation PAN is 240-310°With, its duration from 10 to 180 minutes. This process differs from the known process of oxidative processing of yarns and fabrics from one PAN fiber temperature-time regime, namely a high temperature heat treatment and lesser duration.

It is known that to obtain OPEN fibers as a starting material using conventional PAN fibers and type Nitron produced from a copolymer of Acrylonitrile with other monomers (methacrylate, taconova acid and others). The use of copolymers reduces the temperature of thermal-oxidative treatment of PAN fibers and increases the yield of the final thermolabile is consistent fiber (the journal "Chemical fibres, 2003, №6, p.3-6). Used PAN fiber-based copolymer of the following composition: Acrylonitrile was 92.3%, methacrylate 6.5% and taconova acid of 1.2%.

It is also known that the oxidation of PAN fibers, including thermal-oxidative dehydrogenation and cyclization with the formation of naphthyridinone cycles is carried out in air when heated in the temperature range 240-350°C. the time-Temperature conditions are selected such that increasing the glass transition temperature (softening) PAN fiber remained higher than the temperature of treatment and remained oriented supramolecular (fibrillar) the structure and form of the fiber to its full transition into a structured infusible, neraspavsheysya material (journal of Chemical fibers", 2002, №4, p.32-40). At the specified temperature and glass transition temperature of heat-resistant polymers. Therefore the heat treatment is carried out also at these temperatures, ensuring the passage of additional crystallization of the polymer with the elimination of heat shrinkage of the fibers and their thermal hardening. In this connection it is possible to combine the process of oxidation PAN in composite material with the heat strengthening process, for example, aramid fibers.

The above conditions of thermal oxidation of the PAN are pretty tough and unacceptable for conventional natural is s and chemical fibers. Therefore, the invention relates to a technology for termignoni textile materials based on heat-resistant and PAN fibers subjected to thermal-oxidative transformations in the form of ready mixed product.

As the heat-resistant fibers for mixing with PAN fibers, it is recommended to use industrial methanamine (Nomex, konex, Carmel) or para-aramid (Kevlar, Twaron, fiber-based depolimerizatia), as well as fiber-based polyparaphenylene-1,3,4-oxadiazole (Exelon) and in particular pilot metoposauridae fibers into the polymer for which, along with the links of the meta - and paraphenylenediamine includes a certain number of links with benzimidazole cycles. They are described in the patent of the Russian Federation 2180369, 2000 and the patent of the Russian Federation 2285760, 2006, Their advantage lies in the possibility of hardening of the fibers during the heat treatment without stretching, that is, in the free state, which is convenient to use the heat treatment of textile materials.

As a mixed textile materials of heat-resistant and PAN fibers receive the yarn, and strip width of 3 cm and fabric width 115 see Periodic processes for heat treatment of yarns and ribbons were carried out in laboratory heating Cabinet with adjustable temperature and a continuous process for heat treatment of ribbons and fabrics - the shop and production lines, intended for oxidation of PAN harnesses and PAN fabrics as the first stage of production of carbon materials. When periodic heat-treated yarn was in isometric condition (mounted on metal frames), and tape, in addition, in the free state. The speed of the tape at the shopfloor production line corresponded to the 10-minute stay in the furnace, and the fabric stays in the furnace from 10 minutes to 3 hours.

Yarn and ribbon from a mixture of aramid, POLYACRYLONITRILE fibres with a mass ratio of 30/70, 50/50 after oxidative treatment, as aramid material without PAN, have a brown color. Therefore, the above ratio fibers color aramid masks black color, OPEN. For dyeing black, it is recommended to use specially obtained aramid fiber, pan containing the additive in the amount of 5-15%, introduced in the spinning solution of aramid on the patent of the Russian Federation 2210649, 2001

The invention is illustrated in the following examples.

Example 1

Yarn from a mixture of fibers was obtained using aramid fiber-based copolymer consisting of 50% of the links metaphenylenediamine, 20% of the links paraphenylenediamine and 30% of the links 5(6)-amino-2(paraaminophenol)benzimidazole and terephthaloylchloride described in the patent of the Russian Federation 2285760, 2006, and fiber Nitron corresponding to THE 2272-041-05757601-97.

A mixture of bales of fibers Provo is or Ripper to obtain a mixed composition with a mass ratio of 80/20 and 50/50 aramid fiber and Nitron.

Physico-mechanical properties of individual fibers are shown in table 1

Table 1
Name of indicatorAramid fiberNitron
Linear density0,220,33
Strength, CN/Tex29,025,0
Elongation at break, %13,035,0
Fiber length, mm7070
Frequency crimp, Izv./cm3,24,0

Processing the mixture of fibers in the yarn was carried out according to the technology of processing of wool on two systems-spun using ring spinning and open-end spinning machines with similar results and included a loosening of the mixture, the formation of the canvas, getting the card sliver, sliver, rovings, of single yarn, twist yarn.

Yarn and produced from her belt and fabric had the following characteristics (table 2).

For carrying out the heat treatment of a mixed yarn with the aim of oxidation of polyacrylonitrile samples were wound on a frame (isometric conditions) and heated in a heating Cabinet in air (table 3). Similarly Provo is or heat treated ribbons, obtained from the same yarn in isometric conditions, the samples were put in frames) in the free state (table 4).

Table 3
Conditions of heat treatment of yarnIndicators of yarn commodity composition of 50/50
Temperature, °Duration, minLinear density, TexStrength, CN/TexBreaking elongation, %
Heat treatment no83,616,37,0
2402083,716,37,2
2406075,621,08,2
24018077,021,38,9

Effect of heat treatment of the yarn appeared after 60 minutes (table 3). It is to reduce the linear density due to drying and outgassing material, as well as in a significant increase of strength and rupture elongation. Nitron fiber in the yarn are black, and the non-flammable yarn.

Table 4
Conditions thermobreak the tapes Indicators tapes commodity composition of 50/50
Temperature, °Duration, minState sampleLinear density, g/mThe breaking load, kgfBreaking elongation, %
Heat treatment no8,6967,213,8
25030isometric8,3079,416,3
--"--60--"--8,4282,016,4
--"--90--"--8,4475,314,7

Continuation of table 4
Temperature, °Duration, minState sampleLinear density, g/mThe breaking load, kgfBreaking elongation, %
28015isometric8,3079,416,3
--"--30--"--8,2580,716,1
--"--45-"-- by 8.2281,314,0
3006isometric8,2387,713,6
--"--15--"--8,3388,014,0
--"--30--"--of 8.4784,313,3
25030free9,1071,022,9
--"--60--"--8,7980,821,6
--"--90--"--8,8980,021,7
28015free9,1072,325,7
--"-30--"--8,8076,122,7
--"--45--"--by 8.2272,322,3
3006free9,0072,720,0
--"--15--"--9,1175,724,9
--"--30--"--9,20 67,021,0

From the data of table 4, it follows that:

- the linear density of the tape is reduced in case of carrying out heat treatment in isometric conditions in the drying and outgassing of the material; on the contrary for tapes, heat-treated in a free state, it increases because of the predominance of the contribution of thermal shrinkage;

- the breaking load tapes in all cases the result of the heat treatment increases, but when heated in a free state it increases to a lesser extent, due to restructuring and strengthening of aramid, since the oxidation of polyacrylonitrile fibers, their strength decreases;

positive is a significant increase in the rupture elongation in all bands, especially when heated in a free state that for textiles is an important parameter characterizing their elasticity.

After the oxidative treatment, the ribbon does not light up in flames in contrast to the original tapes. They charred, but the burning and decay is not observed. As a result of tests on the resistance to open flame GOST 15898-70 shown that the tapes do not burn. Group Flammability heat-treated ribbons, GOST 12.1.044-89 - combustible.

Yarn and ribbon from a mixture of aramid and polyacrylonitrile after oxidative treatment have brown C is et.

Continuous thermal-oxidative treatment was carried out on a production line intended for oxidation of polyacrylonitrile harnesses (as the first stage of obtaining carbon materials) technology, providing the tension by setting the difference of the rotation speeds of the rollers before and after furnace component in this case 2% for the ratio of fibers in the ribbon 50/50. In a continuous process achieved higher strength tapes, however, with a significant decrease in rupture elongation. In addition, to obtain non-combustible materials with short-term implementation of the process within 10 minutes you want to use a temperature of about 300°With (table 5).

Table 5
Conditions for continuous heat treatment of the tapes under tensionIndicators tapes commodity composition of 50/50Flammability tapes
Temperature, °Duration, minLinear density, g/mThe breaking load, kgfBreaking elongation, %
Heat treatment no8,6967,213,8Burns
250107,8984,0/td> 10,0--"--
270107,9484,09,6--"--
300107,4698,09,5Not lit

Continuous thermal-oxidative treatment of ribbons and fabrics with a ratio of fibres by weight of 80/20 listed in table 2, was carried out on production lines, intended for the oxidation of acrylic binders and tissues as the first stage of obtaining carbon materials technology with slight tension due to shrinkage by setting the same speed of rotation of the rolls before and after the furnace. The obtained flame-retardant tape at a temperature of processing 300°and duration of 10 minutes and the fabric at a temperature of processing 240°and With the duration of 2 hours.

Example 2 (comparative)

Yarn was obtained from a mixture of 70% metaparameter fiber-based polymer with a chemical composition shown in example 1, and 30% oxidized polyacrylonitrile fiber processing cotton open-end-spinning method.

Physico-mechanical properties of individual fibers and yarn are shown respectively in table 6 and 7.

Table 6
The UNESCO is the indicator Aramid fiberOxidized polyacrylonitrile fiber
Linear density, Tex0,2610,192
Strength, CN/Tex26,013,2
Breaking elongation, %19,019,2
Fiber length, mm38to 38.3
The number of svetcov 1 cm3,03,0
Table 7
Name of indicatorYarn from 100% aramid fiberYarn raw material composition 70/30
29 Tex29×2 Tex
The actual linear density, Tex28,528,5×236,6
Strength, CN/Texthe 9.712,96,1
Breaking elongation, %7,3 9,37,0
Twists per 1 m720450720

Production of mixed yarn raw material composition 70/30 went with difficulties associated with the shooting down of the equipment units and the breakage of the yarn. Due to the increased fragility of oxidized polyacrylonitrile fibers on all transitions generated large quantities of fluff, consisting of fragments of fiber. The strength of this yarn (6,1 CN/Tex) was below the established requirements for the yarn for weaving and knitting purposes, although it should be at a level not lower than 8 CN/Tex, if to compare with the figures of yarn from 100% aramid fiber.

Example 3

Yarn from a mixture of fibers received in accordance with the description in example 1. Mixing took 50% acrylic and 50% modified aramid fibers with a composition of 90% aramid copolymer and 10% polyacrylonitrile. As aramid copolymer was used, the copolymer consisting of 70% of the links metaphenylenediamine and 30% of the links 5(6)-amino-2(paraaminophenol)benzimidazole and terephthaloylchloride described in the patent of the Russian Federation 2180369, 2003, Polyacrylonitrile was included in the polycondensation solution after synthesis aramid copolymer for forming the fibers on the patent of the Russian Federation 2210649, 2003 Aramid fiber switch is of polyacrylonitrile had the following indicators T/P/U=0,24/30/17, where T is the linear density, Tex; P-strength, CN/Tex; - breaking elongation, %. Got the yarn from a mixture of fibers with the performance of the T/P/Y=29,4x2/16,0/9,0, from which was developed the cloth of twill weave 2×2, width 115 cm, weighing 250 g/m2.

Continuous thermal-oxidative tissue processing was carried out on a production line intended for oxidation of polyacrylonitrile fabrics as the first stage of obtaining carbon materials technology, providing a 10%shrinkage with minimal tension and temperature 280°C for 60 minutes. Received the finished fabric in black with a breaking load on strip 50×100 mm, 12% more than for the same fabric to heat treatment, and a breaking elongation of 14%. The fabric is non-flammable. Black color fabric provided not only oxidized polyacrylonitrile fiber, but black aramid fibers, containing 10% OPEN.

Example 4

Yarn from a mixture of fibers received in accordance with the description in example 1. Mixing took 30% of para-aramid fiber, Twaron (fiber from polypara-phenyleneterephthalamide) with a linear density of 0.17 Tex, cutting length 60 mm, corrugated, with the strength of 160 CN/Tex and a breaking elongation of 3.4% and 70% acrylic fibre. Made of yarn of a linear density of 29.4×2 Tex with a strength of 22 CN/Tex and a breaking elongation of 6.0% of you who amityvale the band width of 3 cm with a linear density of 6.1 g/m, the number of threads on the base 20 and duck 12 to 1 cm in length and width. The breaking load of the tape 65 kgf, breaking elongation of 14%.

Oxidative processing of the tapes was performed in a heating Cabinet in the air in isometric conditions at 250°C for 90 minutes. Received non-flammable tape black color with a linear density of 5.7 g/m breaking load of 40 kgf and a breaking elongation of 10%.

Example 5

Yarn from a mixture of fibers received in accordance with the description in example 1. Mixing took 50% metaraminol fiber Nomex fiber from polymethacrylamide) with a linear density of 0.17 Tex, cutting length 50 mm, corrugated, with a strength of 42 CN/Tex and a breaking elongation of 22% and 50% acrylic. Made of yarn of a linear density of 29.4×2 Tex has developed a band width of 3 cm with a textile structure, described in examples 1 and 3 with a linear density of 6.4 g/m

Oxidative processing of the tapes was performed in a heating Cabinet in air under isothermal conditions at different temperatures from 240°With up to 310°and a duration of from 30 to 180 minutes. Received non-flammable tape brown shade with a linear density of 6.0 to 6.1 g/m breaking load by 10-15%, inferior to the breaking load for tapes prior to heat treatment.

Similarly, by carrying out thermal-oxidative treatment received non-flammable textile material (flax is s) of the composite yarn on the basis of acrylic and other fibers of heat-resistant polymers: heat-resistant and non-combustible metronidozole staple fiber kernel (for 80% of Carmela and 20% of Nitron); heat-resistant and morogorogo staple fiber terlon (fiber of a copolymer consisting of 90% of the links paraphenylenediamine with 10% links parabasalia, with a linear density of 0.33 dtex, a strength of 40 CN/Tex and a breaking elongation of 12%). His oxygen index of 29, which increased to 31 for 80% of terlano and 20% of Nitron after oxidative treatment strips with a linear density of 6.4 g/m and a width of 3 cm at 280°C for 30 minutes.

Received in the same way malagarasi textile material (tape) from a mixed yarn-based and heat-resistant Nitron, but fuel staple fiber, Exelon (polyparaphenylene-1,3,4-oxadiazoline fiber with an oxygen index of 22). Material from a mixed yarn composition of 70% acrylic and 30% of okalona after oxidative treatment can be attributed to malagarasi, and the presence of okalona in textile materials of an oxidized polyacrylonitrile fiber imparts increased resistance to abrasion.

Example 6

Yarn from a mixture of fibers received in accordance with the description in example 1. Mixing took aramid fiber and fiber Nitron shown in example 1. Physico-mechanical properties of individual fibers is shown in table 1. A mixture of bales of fibers held in the CSD to obtain a mixed composition with a mass ratio of 30/70 aramid fiber and n is the throne.

Got the yarn linear density of 29.4×2 Tex with strength 16 CN/Tex and a breaking elongation of 9%, with the number of turns 2-thread yarn 310 kr./m

The yarn was processed into a fabric width of 115 cm twill weave 2×2 number of threads-1.0 cm of fabric in the warp and weft 20 weighing 235 g/m2. The breaking load on the basis of the piece of fabric with a width of 50 mm (duck) and a length of 100 mm (50×100 mm) was 85 kgf, and a fracture elongation of 16%.

Continuous thermal-oxidative tissue processing was carried out on a production line intended for oxidation of polyacrylonitrile fabrics as the first stage of obtaining carbon materials technology with slight tension due to shrinkage by setting the same speed of rotation of the rolls before and after the furnace at a temperature of 24°and time 3 hours. Received non-flammable fabric dark brown, with a surface density of 247 g/m2, which had a breaking load 71 kgf (strips of fabric 50×100 mm) and breaking elongation of 14%.

1. The method of obtaining termignoni textile materials from a mixture of heat-resistant synthetic fibers and oxidized polyacrylonitrile fibers, characterized in that the first mix of heat-resistant synthetic fiber with non-oxidized polyacrylonitrile fiber mass ratio of from 30/7 to 80/20, and then oxidize the mixture directly in the form of yarns, ribbons, fabrics when 240-310°for 10-180 minutes

2. The method according to claim 1, characterized in that as the heat-resistant synthetic fibers using at least one kind of fibers of the following polymers: MetaFrame, paraaramid, meta-paraaramid with benzimidazole cycles in the main chain, metaraminol, polyparaphenylene-1,3,4-oxadiazol.



 

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31 cl, 6 dwg, 9 ex

FIELD: chemistry.

SUBSTANCE: present invention pertains to production of high-strength and high-modulus carbon ribbons, obtained from polyacrylonitrile threads and can be used for making high-tech composites. The method of making the ribbons involves putting the polyacrylonitrile threads on a textile machine, weaving a ribbon on the textile machine, thermal stabilisation of the obtained ribbon, carbonisation, electrochemical treatment, textile finishing and winding. Before thermal stabilisation, from 0.25 to 0.90 of the output of the textile machine per hour is accumulated. All operations take place in continuous mode. The production line for the given ribbons comprises furnaces for thermal stabilisation and carbonisation, apparatus for electrochemical treatment and textile finishing, a winding machine and equipment for transportation of the ribbons, fitted between the elements of the production line. Before the thermal stabilisation furnace, there is bobbin holder with warper's bobbins, textile machine and ribbon accumulator.

EFFECT: higher output due to longer operation between replacements (increased running time of the equipment).

8 cl, 3 dwg, 3 ex

FIELD: chemistry.

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.

11 cl

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