RU2803288C1 - Halogenated polymer based on nitrile rubber and method for its production - Google Patents

Abstract

FIELD: rubbers.

SUBSTANCE: present invention relates to heat-resistant nitrile butadiene rubber and a method for its production. A halogenated polymer based on nitrile rubber is a heat-resistant halogenated diene-containing copolymer, which contains from 20 wt.% to 75 wt.% of halogenated groups based on the total weight of the copolymer, is characterized by a temperature of 5% weight loss from 230°C to 265°C, weight average molecular weight 50-200 thousand amu, content of residual double bonds of at least 0.5 wt.% based on the total weight of the copolymer, softening point of at least 120°C, an average granule size of 20 mcm. A method is also described for producing the above halogenated polymer based on nitrile butadiene rubber, which includes the following steps: a) dissolving the original copolymer in a hydrocarbon solvent by stirring at a temperature of 10 to 50°C, whereas the mass ratio of the hydrocarbon solvent to the original copolymer can be from 5:1 to 30:1, the dissolution process time is from 10 to 60 minutes; b) halogenation is carried out by adding the solution of the initial copolymer obtained in step a) in a hydrocarbon solvent to the halogenating agent, the molar ratio of the initial copolymer and the halogenating agent is from 1:1.5 to 1:5, the ratio is chosen in such a way as to ensure the achievement of the pH no more than 5.5; halogenation is carried out at a temperature from 0 to 50° C, the process time is from 15 to 120 minutes, whereas the resulting mass comprises a halogenated copolymer and a solvent; c) neutralizing the reaction mass obtained in step b) containing the halogenated copolymer solution by adding an aqueous solution of a neutralizing agent, followed by washing the neutralized reaction mass with water and separating the aqueous layer and the organic layer containing the halogenated copolymer, whereas the molar ratio of the neutralizing agent and the halogen added at stage b) in the modifying system is from 1:1 to 3:1, whereas the ratio is chosen in such a way as to ensure the achievement of a pH of at least 7.5; the neutralization process is carried out at a temperature of 15 to 50°C, wherein the neutralization is carried out using at least a one-time excess of water relative to the volume of the reaction mass subjected to neutralization, resulting in the separation of the reaction mass into two layers: an organic layer containing a halogenated copolymer and an aqueous layer; d) separating the halogenated copolymer by precipitation, to precipitate the halogenated copolymer, an alcohol-precipitant is added to the organic layer obtained in step c) in a mass ratio of alcohol-precipitant: halogenated copolymer from 1 to 10; f) the halogenated copolymer is filtered at a temperature of 20 to 40°C inclusively and the copolymer is dried at a temperature of 50 to 105°C and pressure from 1 to 20 kPa.

EFFECT: obtaining a halogenated polymer based on nitrile-butadiene rubber with improved properties of its distribution in the polystyrene mass, as well as providing high fire-retardant properties to expandable polystyrene.

12 cl, 1 dwg, 1 tbl, 7 ex

Description

Field of technology to which the invention relates

Group of inventions “Halogenated polymer based on nitrile-butadiene rubber and a method for its production” relates to a heat-resistant butadiene-nitrile block copolymer, mixed polymer compositions and methods for their production. The group of inventions can be used in the chemical industry and in other areas of industrial production aimed at producing and using polymer materials with fire retardant functions, such as construction, the automotive industry, the production of household appliances and electronics.

State of the art

Known invention BROMINATED

BUTADIENE/VINYLAROMATIC COPOLYMERS, MIXTURES OF SUCH COPOLYMERS WITH VINYLAROMATIC POLYMER AND POLYMER FOAM MATERIALS OBTAINED FROM SUCH MIXTURES (patent document RU 2414479 C2), heat-resistant brominated copolymer, wherein the copolymer contains butadies polymerized in it an ene fragment and a vinyl aromatic monomer fragment, and before bromination the copolymer characterized by a content level of vinyl aromatic monomer in the range from 5 to 90% wt. based on the weight of the copolymer, a level of 1,2-butadiene isomer greater than 0 weight percent based on the weight of the butadiene moiety, and a weight average molecular weight of at least 1000, wherein the brominated copolymer is characterized by a level of unbrominated, non-aromatic double bonds , less than or equal to 15% based on the level of non-aromatic double bonds in the copolymer before bromination as determined by 1H NMR spectroscopy, and a five percent mass loss temperature of at least 200 degrees Celsius as determined by thermogravimetric analysis ( TGA). Also described is a method for producing the above heat-resistant brominated copolymer, where mild and selective agents such as tetraalkylammonium tribromide or pyridinium tribromide can be used as a brominating agent, a polymer mixture containing a vinyl aromatic polymer and a flame retardant amount of the above brominated copolymer is described, and a molded a product containing the above polymer mixture.

The disadvantages of this flame retardant include relatively low thermal stability, which manifests itself at high temperatures of polystyrene processing and limited compatibility of highly brominated butadiene-styrene block copolymers, which can cause difficulties in obtaining a homogeneous structure of foaming polystyrene. The disadvantages of the disclosed production method include the use of expensive halogenating agents, as well as the need for their subsequent effective extraction from the resulting product, since they can negatively affect the properties due to their presence in it.

Brominated and epoxidized combustion retardants are known (patent document RU 2530021 C2), within the scope of the patent description a brominated and epoxidized organic compound is claimed, having a molecular weight of at least 1500, in which bromine atoms are bonded directly to aliphatic carbon atoms, and the brominated and epoxidized organic compound is a brominated and epoxidized butadiene homopolymer or a brominated and epoxidized ester of a polyol and one or more fatty acids, and has a bromine content of at least 35% by weight, and at least one oxirane group in the molecule, and where the brominated and epoxidized organic compound has a temperature of 5% mass loss of at least 180°C. Variants of the method for producing brominated and epoxidized organic compounds and an organic polymer composition are also claimed.

The disadvantage is that despite the fact that this fire retardant contains epoxy groups that increase the effectiveness of antipyretic properties and are designed to absorb HBr released during the combustion of polymer compositions based on foaming/extruded polystyrene, low compatibility of such a fire retardant with polystyrene is observed.

A known method for producing a modified diene-containing (co)polymer and its use as a fire retardant (patent document RU 2732675 C1) which includes the stages: a) halogenation of a solution of a diene-containing (co)polymer in an organic solvent to form a reaction mass containing a halogenated diene-containing (co)polymer in an organic solvent, as well as a vapor-gas mixture containing a solvent and an excess amount of unreacted halogen; b) neutralizing the reaction mass obtained in step (a), followed by separating the aqueous and organic layers, where the aqueous layer contains water, a residual amount of neutralizing agent and, optionally, a solvent, and the organic layer contains a halogenated diene-containing (co)polymer and a solvent; c) deposition of the organic layer obtained in step (b) to separate the target product - a halogenated diene-containing (co)polymer, followed by filtration and drying of the precipitated product; and d) neutralizing the excess amount of unreacted halogen from the vapor-gas mixture from step (a) by passing said vapor-gas mixture through the aqueous layer obtained in step (b) containing water, residual amounts of the neutralizing agent and, optionally, a solvent. A modified diene-containing (co)polymer is used as a flame retardant (fire retardant) for polymer compositions based on foaming polystyrene. The technical result is the development of an economical and simple method suitable for industrial use for producing a halogenated diene-containing (co)polymer, which ensures the effective removal of excess amounts of unreacted halogen from the vapor-gas mixture formed during the halogenation process.

The disadvantage of this solution is the production of a fire retardant with relatively low thermal stability, which manifests itself at high temperatures of polystyrene processing and limited compatibility of highly brominated butadiene-styrene block copolymers.

The closest analogue is a MODIFIED (CO)POLYMER, METHOD OF ITS PRODUCTION AND APPLICATION (patent document WO2020139110), within which a hydroxy-epoxy-brominated diene-containing (co)polymer is disclosed, characterized by a temperature of 5% weight loss of at least 180°C , and suitable for use as a fire retardant for polystyrene. The described fire retardant does not have many of the disadvantages inherent in the fire retardants described above, however, the heat resistance of this fire retardant also turns out to be insufficient under processing conditions, and the resulting expanded polystyrene granules containing this fire retardant exhibit color, which limits their use in a number of areas, in particular, in the production of decorative materials. panels. In addition, fire retardants that can be used in the production of extruded polystyrene are subject to increased heat resistance requirements. It is important that it can undergo very little thermal degradation, preferably no thermal degradation in melt mixing, injection molding and extrusion foaming processes (and other processes involving the use of polymer melts), where temperatures can exceed 200°C, sometimes reaching up to 230 °C. In addition to heat resistance, such flame retardants must demonstrate other key characteristics, including compatibility with foamable polymers and foaming agents used in foaming, and no adverse effect on foam cell formation or foam cell size. Thus, another disadvantage of the fire retardant disclosed in the closest analogue is its insufficient heat resistance for use in the production of extruded polystyrene, and the presence of hydroxy groups in the structure of the fire retardant can lead to negative effects in the production of extruded polystyrene, in particular a decrease in thermal stability and melting point, which leads to deterioration of strength characteristics and fire retardant properties.

Thus, within the current field of technology, the problem of obtaining polymer flame retardants that are equally suitable for both foaming and extruded polystyrene, characterized by increased heat resistance, and also exhibiting good compatibility and at the same time providing excellent fire retardant properties to polystyrene, has not been solved.

It is an object of the present invention to overcome the above disadvantages by developing a halogenated nitrile rubber based polymer which can be used as a flame retardant for polystyrene suitable for all applications.

Disclosure of the invention

The technical result consists in obtaining a halogenated polymer based on nitrile butadiene rubber with improved properties of its distribution in the polystyrene mass, as well as providing high fire-retardant properties to foaming polystyrene, satisfying the following characteristics:

- temperature of 5% weight loss of at least 230°C,

- weight average molecular weight 50-200 thousand amu,

- the content of residual double bonds is at least 0.5 wt. % based on the total weight of the copolymer,

- softening temperature not less than 120°C.

An additional technical result consists in obtaining, according to one embodiment of the invention, a halogenated polymer based on nitrile butadiene rubber with an average granule size of at least 50 microns, which ensures the production of a finished copolymer having the required bulk density (not more than 500 g/l), as a result which eliminates the need to crush granules of the halogenated butadiene-nitrile block copolymer and improves its compatibility with styrene.

Another technical result is to increase the fire-retardant properties of a halogenated polymer based on nitrile-butadiene rubber due to the presence of nitrogen-containing groups in the polymer structure, which leads to a reduction in consumption rates in the manufacture of fire-resistant products and an increase in the antipyretic properties of the product.

The present invention relates to a halogenated copolymer of conjugated diene and acrylonitrile, as well as a mixture of conjugated diene and acrylonitrile with a copolymer of conjugated diene and monovinyl aromatic hydrocarbon and a method for producing the claimed products.

The copolymer of conjugated diene and acrylonitrile has a weight average molecular weight of 50-200 thousand amu, preferably 60-150 thousand amu, more preferably 70-100 thousand amu. The acrylonitrile block content is at least 20% by weight, preferably at least 25% by weight. %, more preferably 30 wt. % based on the total weight of the copolymer.

The copolymer of a conjugated diene and a monovinyl aromatic hydrocarbon has a weight average molecular weight of 50-150 thousand amu, preferably 60-130 thousand amu, more preferably 70-120 thousand amu. The content of the monovinyl aromatic hydrocarbon block is at least 20% by weight, preferably at least 25 wt. %, more preferably 30 wt. % based on the total weight of the copolymer.

The resulting halogenated diene-containing copolymer contains at least 20 wt. %, preferably at least 50 wt. %, more preferably 75 wt. % or more halogenated groups based on the total weight of the copolymer.

According to the present invention, the resulting halogenated nitrile rubber polymer is a heat-stable halogenated diene-containing copolymer which has a 5% weight loss temperature of at least 230° C., preferably at least 245° C., more preferably at least at least 265°C.

The resulting halogenated nitrile rubber polymer has an average granule size of at least 50 microns, preferably at least 30 microns, most preferably at least 20 microns.

Structural formulas:

Where

x - halogenated butadiene block y - acrylonitrile block

Where

x - vinyl bezol block

y, z - halogenated butadiene block

n - acrylonitrile block.

To practice the present invention, the halogenated nitrile rubber polymer of the present invention can be produced by a process that includes the following steps:

a) dissolution step (optional): dissolving the starting copolymer/polymer mixture in a hydrocarbon solvent, wherein the starting copolymer is optionally subjected to pre-grinding prior to said dissolution;

b) halogenation step: adding the dissolved copolymer from step a) to the halogenating agent (or vice versa);

c) neutralization and separation stage: adding an aqueous solution of a neutralizing reagent to the reaction mass obtained in stage b) and separating the aqueous and organic layers;

d) separation step: precipitation or degassing of the halogenated copolymer from the organic layer obtained in step (c);

e) the step of filtering and drying the halogenated copolymer isolated in step (d).

Brief description of drawings

Figure 1 shows a block diagram of the preparation of the claimed compound. The numbers on the figure indicate:

1 - block for dissolving the initial block copolymer

2 - halogenation block

3 - neutralization block (if necessary)

4 - block for washing and separating the reaction mixture

5 - selection block Implementation of the invention.

The claimed connection can be obtained by following the following procedure:

Stage a) dissolution

At this stage, the initial copolymer is dissolved in a hydrocarbon solvent. The starting copolymer may optionally be pre-comminuted before dissolution.

Grinding of the initial conjugated copolymer can be carried out by any methods known from the prior art, for example, using crushers (knife, hammer, rotary), mills (jet, screw), etc.

Dissolution of the starting copolymer can occur with stirring. Mixing can be carried out by any method known from the prior art, for example, using an apparatus with a stirrer, a static mixer. Mixing can take place at a temperature of from 10 to 50°C, preferably from 15 to 40°C, more preferably from 20 to 30°C.

Suitable solvents may include, but are not limited to, hydrocarbon solvents, preferably having a purity of 99% or greater, and being ethers, for example, tetrahydrofuran, halogenated saturated aliphatic hydrocarbons, for example, carbon tetrachloride, chloroform, dibromomethane, dichloromethane, 1,2 -dichloroethane, cycloaliphatic hydrocarbons, for example cyclohexane, aromatic hydrocarbons, for example toluene, halogenated aromatic hydrocarbons, for example bromobenzene, chlorobenzene and dichlorobenzene. Preferred hydrocarbon solvents are those that are liquid under the conditions of halogenation of the starting copolymer, and which do not react with the modifying system or the starting copolymer. Preferably, the solvent used is chloroform, dichloromethane, dichloroethane, toluene, most preferably chloroform, dichloromethane is used.

The weight ratio of hydrocarbon solvent to starting copolymer may be from 5:1 to 30:1, preferably from 8:1 to 20:1, more preferably from 12:1 to 15:1.

The dissolution process can take no more than 60 minutes.

The mass obtained as a result of the dissolution step described above is a solution of the original copolymer in a hydrocarbon solvent.

Stage b) halogenation

At stage b) the modification involves adding the solution of the original copolymer obtained in stage a) in a hydrocarbon solvent to a halogenating agent (or vice versa, a halogen solution to a copolymer solution).

Chlorine, fluorine, bromine or iodine can be used as the halogen in the halogenating agent. It is preferable to use bromine, since the resulting iodine-containing and chlorine-containing modified copolymers are less stable over time and thermally stable than bromine-containing ones.

As a halogenating agent, molecular bromine (Br2) can be used as such, as well as in the form of a solution in a hydrocarbon solvent with a bromine content of 50 wt. % up to 70 wt. %, more preferably no more than 60 wt. %, most preferably no more than 50 wt. %.

Suitable halogenating agents also include, but are not limited to, quaternary ammonium bromides, for example, phenyltriethylammonium bromide, benzyltrimethylammonium bromide, tetramethylammonium bromide, tetraethylammonium bromide, tetrapropylammonium bromide, tetra-n-butylammonium bromide, and quaternary phosphonium bromides, for example, tetramethylphosphonium bro mid, tetraethylphosphonium bromide, tetrapropylammonium bromide, tetra-n-butyl-ammonium tribromide, or mixtures thereof.

Preferably, a mixture of molecular bromine (Br2) and quaternary ammonium bromides or quaternary phosphonium bromides is used as the halogenating agent. The use of quaternary ammonium bromide or quaternary phosphonium bromide avoids significant substitution of hydrogen with bromine at tertiary and/or allylic carbon atoms, which, in turn, affects the thermal stability of the resulting halogenated copolymer.

The molar ratio of the starting copolymer to the halogenating agent may be from 1:1.5 to 1:5, more preferably from 1:2 to 1:4, most preferably from 1:2.5 to 1:3. The ratio is chosen in such a way as to ensure the achievement of a pH value of no more than 5.5.

The halogenation step of the invention can be carried out at a temperature of -5 to 50°C, preferably 5 to 45°C, more preferably 10 to 30°C, and atmospheric pressure.

The time of the modification step can be any convenient time sufficient to achieve the desired degree of modification of the starting block copolymer described above. Preferably, the modification time is at least 15 minutes, at least 20 minutes, at least 25 minutes, at least 30 minutes, at least 45 minutes, at least 60 minutes, at least 120 minutes.

The mass obtained at stage b) contains the target product - a halogenated copolymer and a solvent.

Stage c) neutralization and separation

The neutralization stage is carried out when the ratio of the original copolymer and the halogenating agent is violated and the pH value is less than 5.5.

Step c) involves neutralizing the reaction mass containing the halogenated copolymer solution obtained in step b) by adding a solution of a neutralizing agent, followed by washing the neutralized reaction mass with water and separating the aqueous layer and the organic layer containing the halogenated copolymer.

As a neutralizing agent, aqueous basic solutions known from the prior art can be used, but are not limited to them, for example, solutions of sodium hydroxide, sodium thiosulfate, sodium bisulfite, sodium carbonate. Preferably, an aqueous sodium hydroxide solution is used.

The molar ratio of the neutralizing agent to the halogen added in step b) in the modifying system can typically be from 1:1 to 3:1, preferably from 1:1 to 2:1, more preferably 1:1. The ratio is chosen in such a way as to ensure the achievement of a pH value of at least 7.5.

Preferably, the neutralization process is carried out at a temperature of 15 to 50°C, preferably 20 to 40°C, more preferably 25 to 30°C, and atmospheric pressure.

Washing with water can be carried out using at least one, preferably at least two, more preferably at least three times excess of water relative to the volume of the reaction mass subjected to neutralization, resulting in the separation of the reaction mass into two layers: an organic layer, containing a halogenated copolymer, and an aqueous layer. It is preferable to carry out washing with control of the pH value of the washing water. The pH value should be no more than 8.0.

Separation of the organic and aqueous layers can be carried out using any equipment known from the prior art, for example, using a separating funnel, separator, settling tank. In industry, layer separation can be carried out using density meters.

Stage d) isolation

In the case where the isolation step d) is a process of precipitation of the resulting halogenated copolymer: to precipitate the halogenated copolymer, a precipitating alcohol is added to the organic layer obtained in step c) in a weight ratio of alcohol to precipitant halogenated copolymer from 1 to 10, preferably from 5 to 15, more preferably 4 to 5.

Suitable precipitant alcohols include, but are not limited to, aliphatic alcohols having 1 to 4 carbon atoms. Examples of such alcohols include, but are not limited to, methanol, ethanol, propanol, isopropanol, butanol, isobutanol. Preferably, methanol and ethanol are used as the precipitating alcohol.

In the case where the isolation step d) is the degassing of the resulting halogenated copolymer, the isolation step d) involves adding water to the organic layer obtained in step c) followed by distilling off the water-solvent mixture at elevated temperature and reduced pressure to isolate the target product and removing from it water and/or its vapors, solvent and/or its vapors.

In the context of the present invention, the water may be, but is not limited to, distilled, deionized, demineralized, osmotic, bidistilled water.

In this case, the volume ratio of added water:organic layer can be from 5:1 to 0.1:1, preferably from 3:1 to 1:1, more preferably 2:1.

The temperature of the water when added to the system may be no more than 30°C, preferably no more than 25°C, more preferably no more than 20°C.

Degassing can be carried out in any suitable equipment known in the art, in particular in devices that provide good mixing, heat exchange and maintenance of reduced pressure. Examples of such apparatus include, but are not limited to, continuous or batch agitator, jacketed, or spray drying apparatus.

The temperature of the degassing step may be from 20 to 200°C, preferably from 50 to 180°C, most preferably from 80 to 150°C.

The pressure in the degassing step can be maintained at less than 800 mbar, preferably less than 300 mbar, more preferably less than 100 mbar.

Preferably, the time of the degassing step is at least 30 minutes, more preferably at least 60 minutes, most preferably at least 120 minutes.

Stage e) filtration and drying (after isolation by precipitation)

At stage e) to purify the halogenated copolymer from residual solvent and precipitant alcohol, filtration is carried out in any apparatus known from the prior art, for example, in filters equipped with porous filter partitions, suction filters, etc.

Filtration of the halogenated copolymer can be carried out at temperatures from 20 to 40°C inclusive.

In order to remove water and/or its vapors, solvent and/or its vapors from the resulting halogenated copolymer, the process of drying the said copolymer is carried out. The process of drying a halogenated copolymer can be carried out using physical methods usually used for the separation and purification of organic substances (solvent distillation under reduced pressure, drying in a vacuum oven, etc.), as well as using drying reagents that remove moisture due to adsorption, formation hydrates or chemical reactions with water and solvents.

Drying of the halogenated copolymer can be carried out in any drying apparatus known from the prior art, for example, drum dryers, spray dryers, etc.

Preferably, drying is carried out at a temperature from 50 to 105°C and a pressure from 1 to 20 kPa.

The resulting connection makes it possible to achieve the stated technical result. The applicant conducted studies of both the composition of the halogenated copolymer in all declared temperature/ratio ranges and its properties. To determine the completeness of halogenation and the effectiveness of antipyretic properties, the copolymer undergoes an unsaturation test.

Basic research methods:

Thermogravimetric analysis (TGA)

In order to determine the thermal stability of the resulting modified diene-containing copolymer, the temperature of 5% mass loss was measured by studying the thermal behavior of copolymer samples using synchronous thermal analysis (STA) (combined differential scanning calorimetry (DSC) and thermogravimetry (TG) methods) in accordance with ISO11358.

Experimental conditions: inert atmosphere (argon) in the temperature range from 30°C to 600°C, heating rate - 20°C/min.

Gel Permeation Chromatography (GPC)

The molecular weight characteristics of the samples of the original diene-containing copolymer and the modified diene-containing copolymer were determined by low-temperature GPC in accordance with ISO16014-3 on a liquid chromatograph with a refractometric detector.

Analysis conditions: eluent - tetrahydrofuran; dissolution and measurement temperature - 40°C, eluent flow rate 1.0 ml/min; column PLgel Mixed-C (2-3 pcs). The calculation was carried out using relative calibration using polystyrene standards using the Mark-Houwink constants for the copolymer K = 0.000374, a = 0.699.

Unsaturation test

The determination is based on the addition of iodine at the site of the fire retardant/rubber double bonds in the presence of trichloroacetic acid and mercuric acetate. The solution should remain dark brown.

Determining the free burning time of polystyrene slabs

Determination of free burning time is carried out according to OST 301-05-202-92E (clause 4.8 of the normative act).

The results of laboratory tests are listed in the table:

Example 1 describes the preparation of a halogenated polymer based on nitrile rubber according to the invention. The resulting flame retardant has high thermal stability (264°C), is compatible with styrene, and works effectively in polystyrene compositions (free burning time 1 s).

Example 2 (comparative) describes the preparation of a halogenated polymer based on nitrile rubber with a reduced amount of solvent. In this case, halogenation of the product does not occur; a viscous reaction mass is formed, which cannot be separated into the product.

Example 3 (comparative) describes the preparation of a halogenated polymer based on nitrile rubber with an increased amount of solvent. In this case, increasing the amount of solvent does not lead to a deterioration in the properties of the product, but is excessive from an economic point of view.

Example 4 (comparative) describes the preparation of a halogenated polymer based on nitrile rubber with an increased amount of halogen (bromine) to pH 2.0. In this case, the resulting product is insoluble in styrene due to the binding of molecular units into a wide-mesh three-dimensional network (polymer cross-linking). The product cannot be used for its intended purpose.

Example 5 (comparative) describes the preparation of a halogenated nitrile rubber polymer using degassing/spray drying. In this case, the isolation method does not lead to a deterioration in the properties of the product.

Examples 6 and 7 (comparative) describe the preparation of a halogenated polymer based on nitrile butadiene rubber in a mixture of conjugated diene and acrylonitrile with a copolymer of conjugated diene and monovinyl aromatic hydrocarbon. The resulting products are highly compatible with styrene and can be used in technologies for producing expanded polystyrene.

Claims (17)

1. Halogenated polymer based on nitrile butadiene rubber is a heat-resistant halogenated diene-containing copolymer, which contains from 20 wt.% to 75 wt.% halogenated groups based on the total weight of the copolymer, characterized by a temperature of 5% weight loss from 230°C up to 265°C, weight average molecular weight 50-200 thousand amu, content of residual double bonds of at least 0.5 wt.% based on the total mass of the copolymer, softening temperature of at least 120°C, has an average granule size from 20 microns. 2. A halogenated polymer based on nitrile butadiene rubber according to claim 1, characterized in that it has an average granule size of 50 microns. 3. A method for producing a halogenated polymer based on nitrile butadiene rubber according to claims. 1, 2, including the following stages: a) dissolve the original copolymer in a hydrocarbon solvent by stirring at a temperature from 10 to 50°C, while the mass ratio of the hydrocarbon solvent to the original copolymer can be from 5:1 to 30:1, the dissolution process time is from 10 to 60 minutes; b) carry out halogenation by adding the solution of the starting copolymer obtained in step a) in a hydrocarbon solvent to a halogenating agent, the molar ratio of the starting copolymer and the halogenating agent is from 1:1.5 to 1:5, the ratio is chosen in such a way as to ensure the achievement of the pH value no more than 5.5; halogenation is carried out at a temperature from 0 to 50°C, the process time ranges from 15 to 120 minutes, and the resulting mass contains a halogenated copolymer and a solvent; c) neutralize the reaction mass obtained in step b) containing a solution of halogenated copolymer by adding an aqueous solution of a neutralizing agent, followed by washing the neutralized reaction mass with water and separating the aqueous layer and the organic layer containing the halogenated copolymer, the molar ratio of the neutralizing agent and the added at stage b) the halogen in the modifying system is from 1:1 to 3:1, with this ratio being chosen in such a way as to ensure the achievement of a pH value of at least 7.5; the neutralization process is carried out at a temperature from 15 to 50°C, while neutralization is carried out using at least a one-fold excess of water relative to the volume of the reaction mass subjected to neutralization, resulting in the division of the reaction mass into two layers: an organic layer containing a halogenated copolymer, and an aqueous layer; d) the halogenated copolymer is isolated by precipitation; to precipitate the halogenated copolymer, an alcohol-precipitant is added to the organic layer obtained in step c) in a mass ratio of alcohol-precipitant: halogenated copolymer from 1 to 10; f) filter the halogenated copolymer at a temperature from 20 to 40°C inclusive and dry the copolymer at a temperature from 50 to 105°C and a pressure from 1 to 20 kPa. 4. A method for producing a halogenated polymer based on nitrile butadiene rubber according to claim 3, characterized in that at stage a) the original copolymer is subjected to preliminary grinding before dissolution. 5. A method for producing a halogenated polymer based on nitrile butadiene rubber according to claim 3 or 4, characterized in that either chloroform or dichloromethane or dichloroethane or toluene is used as a solvent in step a). 6. A method for producing a halogenated polymer based on nitrile butadiene rubber according to claim 3, or 4, or 5, characterized in that at stage b) chlorine, fluorine, bromine or iodine is used as a halogen in the halogenating agent. 7. A method for producing a halogenated polymer based on nitrile butadiene rubber according to claim 3, or 4, or 5, characterized in that at stage b) a solution of molecular bromine in a hydrocarbon solvent with a bromine content of 50% is used as a halogen in the halogenating agent up to 70 wt.%. 8. A method for producing a halogenated polymer based on nitrile butadiene rubber according to claim 3, or 4, or 5, characterized in that in step b) quaternary ammonium bromide is used as a halogen in the halogenating agent. 9. A method for producing a halogenated polymer based on nitrile butadiene rubber according to claim 3, or 4, or 5, characterized in that at stage b) a mixture of molecular bromine Br ₂ and quaternary ammonium bromides or quaternary bromides is used as a halogen in the halogenating agent phosphonium. 10. A method for producing a halogenated polymer based on nitrile butadiene rubber according to claim 3, or 4, or 5, or 6, or 7, or 8, or 9, characterized in that at stage c) a hydroxide solution is used as a neutralizing agent sodium or sodium thiosulfate or sodium bisulfite or sodium carbonate or mixtures thereof. 11. A method for producing a halogenated polymer based on nitrile butadiene rubber according to claim 3, or 4, or 5, or 6, or 7, or 8, or 9, or 10, characterized in that at stage d) as an alcohol - The precipitant is aliphatic alcohols with the number of carbon atoms from 1 to 4. 12. A method for producing a halogenated polymer based on nitrile butadiene rubber according to claim 3, or 4, or 5, or 6, or 7, or 8, or 9, or 10, or 11, characterized in that at stage d) isolation represents the degassing of the resulting halogenated copolymer by adding water to the organic layer obtained in step c), followed by distillation of the water-solvent mixture at elevated temperature and reduced pressure in order to isolate the target product and remove water and/or its vapors, solvent and/or its vapor, while the volume ratio of added water: organic layer is from 5:1 to 0.1:1, and the temperature of water when adding it to the system is no more than 30°C, the degassing temperature is from 20 to 200°C, pressure maintained at less than 800 mbar, degassing time is at least 30 min.