RU2537591C2 - Method of production of nanofibres from aliphatic copolyamides by electroforming, composition of forming solution for this method, and method of modifying nanofibres produced by this method - Google Patents

Abstract

FIELD: nanotechnology.

SUBSTANCE: invention relates to the technology of electroforming nanofibres with a diameter not exceeding 500 nm, and the processes occurring in forming nanofibres in the chamber of the forming device. The invention relates to preparing the forming solution to produce nanofibres from aliphatic copolyamides, and methods of modifying nanofibres through various compositions of forming solution. Improvement of consumer properties of products based on the nanofibres is connected with diameter of the nanofibres obtained and with the surface morphology, or the substantial reduction in defects both of nanofibres and the material produced from them. When using the material based on nanofibres from aliphatic copolyamides it is necessary to provide bio-inertness and nontoxicity when in contact with body tissues, and also the possibility of biodegrading and recycling.

EFFECT: invention provides production of fibres with improved physical-chemical properties, which, in turn, improves significantly the product quality.

32 cl, 18 dwg, 2 tbl

Description

The invention relates to the technology of electrospinning of nanofibers with a diameter not exceeding 500 nm, and to processes occurring during the formation of nanofibers in the chamber of the molding device. In particular, the invention relates to the preparation of a molding solution for producing nanofibers from aliphatic copolyamides and methods for modifying nanofibers by means of various compositions of the molding solution.

The purpose of the proposed group of inventions is to obtain nanofibers from aliphatic copolyamides for medical dressings and dressings, as well as for filter materials. The invention allows to eliminate the disadvantages of the known technologies of electrospinning, in which the production of nanofibers is characterized by high energy consumption and low productivity. Also the purpose of the group of inventions is to obtain fibers (with improved physico-chemical properties), which, in turn, significantly improves the quality of the products. Improving the consumer properties of products based on nanofibers is associated with the diameter of the obtained nanofibers and with surface morphology, or with a significant reduction in defects of both nanofibers and the material obtained from them. In addition, when using material based on nanofibers from aliphatic copolyamides, it is necessary to ensure bioinertness and non-toxicity in contact with body tissues, as well as the possibility of biodegradation and disposal.

It is known from the prior art that the physicochemical and physicomechanical properties of materials consisting of polymer fibers are significantly improved by reducing their diameter to the nanometer range. Nonwoven materials based on nanofibers are widely used in the production of medical supplies, filter materials, and membrane materials.

Nanofibers are obtained by electrospinning from polymer solutions under the influence of an electrostatic field. The required properties of the resulting nanofibers are achieved due to the physicochemical properties of the polymer, solvent, modifying additives, as well as parameters of the electroforming process, such as electric field strength and the distance between the electrodes.

An inventive task is to determine the physicochemical properties of the molding solution and the corresponding process parameters, ensuring the achievement of a continuous process of electroforming of nanofibers, forming a defect-free non-woven material with a uniform surface morphology.

Therefore, for the electroforming process it is necessary:

- establish the physico-chemical properties of the molding solution (viscosity, surface tension, electrical conductivity), ensuring its suitability for the conduct of the electroforming process;

- for the established physicochemical properties of the molding solution, determine the conditions for the continuous process of electrospinning of nanofibers (electric field strength, distance between electrodes, temperature and humidity in the electrospinning chamber).

Thus, based on the inventive task, it follows the need to achieve the following technical result:

1. ensuring the continuity of the process of obtaining nanofibers from solutions of aliphatic copolyamides on high-performance equipment for electroforming in a variety of ways (capless and capillary);

2. obtaining a nonwoven material based on nanofibres of aliphatic copolyamides, the properties and characteristics of which provide the desired function of the product, for example, porosity, vapor permeability, sorption, elasticity, biodegradability, antibacterial activity;

3. improve the quality characteristics of the obtained nonwoven material based on nanofibres of aliphatic copolyamides, such as the absence of defects, uniform surface morphology, uniform distribution of nanofibers in diameter.

The invention eliminates the disadvantages of the known technologies of electrospinning, in which the production of nanofibers is characterized by high energy consumption and low productivity. Also the purpose of the group of inventions is to obtain fibers (with improved physicochemical properties), which, in turn, significantly improves the quality of the products. Improving the consumer properties of products based on nanofibers is associated with the diameter of the obtained nanofibers and with surface morphology, or with a significant reduction in defects of both nanofibers and the material obtained from them. In addition, when using material based on nanofibers, it is required to ensure bioinertness and non-toxicity to body tissues, as well as the possibility of biodegradation and disposal.

Technological processes for producing nanofibers include three main stages: the transfer of the formed material into a viscous flow state, the formation of fibers and their curing. The ability of polymers to fiber formation is determined by the following physicochemical properties of the polymer solution: viscosity, surface tension and electrical conductivity, consistent with each other. With different methods of electroforming nanofibers, it is necessary to provide both process parameters and the physicochemical properties of the molding solution. Moreover, the values of viscosity, surface tension and electrical conductivity of the molding solution depend on the nature of the solvent and polymer.

The preparation of polymer nanofibers by electrospinning depends on many parameters, of which three main ones can be distinguished: the properties of the polymer solution, the conditions for the electrospinning process, and the environmental impact on the electrospinning process.

The physicochemical properties of polymer solutions, such as viscosity, electrical conductivity, surface tension, as well as the conditions for conducting the electroforming process (electric field voltage, distance between electrodes, solution feed rate) have a significant effect on the morphology of nanofibers. Accordingly, by varying all these parameters, it is possible to obtain nanofibers with uniform morphology and uniform distribution over the diameter.

An inventive task is to determine the physicochemical properties of the molding solution and the conditions for conducting the electroforming process, providing a nonwoven material based on nanofibers with uniform morphology and uniform distribution in diameter.

Various methods are known in the art for producing polyamide-based fibers, which are mainly used for the production of textiles, yarn, fabrics. Films, faux fur, leather, and household filters are also made from polyamides. Mainly used for these purposes are the technologies of extrusion, sintering, pressing, extrusion, injection molding.

Thus, upon receipt of a molding solution with the desired physicochemical properties of the components, the following technical result is achieved:

- providing the possibility of continuous production of nanofibers from a molding solution based on aliphatic copolyamides when using high-performance technological equipment for electroforming;

- obtaining a non-woven material consisting of nanofibers, the properties and characteristics of which provide the desired purpose and function of the product;

- improving the quality of the obtained material from nanofibers based on copolyamides by determining the optimal physico-chemical properties of the molding solution and its modification.

The invention is known, patent FR 97/01534 from 08.29.1997, RU 2194055, publ. 12/10/2002, IPC C08B 37/00, which uses polycarboxylic polymers using the Eudragits L and S technology. Use copolymers that are prepared in an aqueous medium. The advantage of such copolymers is that, despite the presence of residual traces of aqueous solvents in the polymer structure, their use in medical devices is allowed. However, solutions based on these copolymers cannot be used in electroforming.

The invention is known "A method of obtaining a filter material, filter material and a means for protecting respiratory organs", patent RU 2385177, publ. 03/27/2010, IPC B01D 39/16, in which electroforming is carried out from a polymer solution in an organic solvent having a viscosity of 3.5-5.0 Poise at an electric field voltage of 60-140 kV, a tetraethylammonium solution is used as a technological additive for controlling the electrical conductivity in ethanol. According to the characteristics of the obtained fiber, the method allows to obtain a filter material with high mechanical characteristics while maintaining the protective characteristics necessary when using this material in respiratory protection. However, this material is not suitable for medical dressings. The technological parameters of this method and the properties of the molding solution do not provide fibers of the desired diameter.

Closest to the proposed method is the invention "A method of producing nanofibers from aliphatic copolyamides by electrospinning", patent RU 2447207, publ. 04/10/2012, IPC D01F 6/80, B82B 3/00, which is defined as a prototype. In accordance with this method, aliphatic copolyamides and an alcohol-water mixture are used as a solvent to obtain a molding solution. Moreover, the invention partially establishes a relationship between the value of the electrostatic voltage in the working chamber of the equipment and the distance between the electrodes. In this case, fibers with a diameter of d = 50-4500 nm are obtained. In addition, only water-ethanol mixtures are used as a solvent at various ratios of components, which leads to phase separation, does not allow for continuity of the electroforming process at room temperature and long-term storage of the molding solution. In addition, the composition of the molding solution cannot be used with the capless method of electroforming.

The basic properties of polyamides can be changed by introducing various additives into their composition: flame retardants, light and heat stabilizers, impact modifiers, hydrophobic additives; mineral fillers, fiberglass, or, as proposed in the present method, the use of mixed polyamides (copolyamides). Mixed polyamides based on ε-caprolactam and salts of adipic acid (polyhexamethylene adipinamide), salts of sebacic acid (polyhexamethylene sebacinamide) at different ratios have good solubility in alcohols, which allows them to be processed through the dissolution stage and to use such solutions as molding during electrospinning in various ways.

Depending on the values of viscosity, conductivity and surface tension of the molding solution, the corresponding technological parameters of the electroforming process are determined, such as the voltage of the electric field, the distance between the electrodes and the humidity in the working chamber. In the proposed method receive nanofibers with a diameter of from 80-400 nm and with uniform morphology.

The proposed method provides the possibility of continuous production of nanofibers from a molding solution based on aliphatic copolyamides when using high-performance technological equipment for electroforming, obtaining a non-woven material consisting of nanofibers, the properties and characteristics of which provide the desired purpose and function, improving the quality of the obtained material from nanofibers, by determining the optimal physico-chemical properties of the molding solution and its modification tions.

This result is achieved due to the fact that the method of producing nanofibers from aliphatic copolyamides by electroforming involves the conversion of an aliphatic copolyamide into a viscous flow state and directly the process of electroforming of nanofibers, and a molding solution is obtained with the specified physicochemical properties, ensuring the continuity of the process of producing nanofibers, by electroforming as on capillary and capillary-free electroforming equipment. The method differs from the known ones in that as a result of dissolution of aliphatic copolyamides in an aqueous-organic mixture with weak acidic properties, a molding solution with the following physicochemical properties is obtained: dynamic viscosity η = 100-800 mPa · s, specific conductivity æ = 40- 250 μS / cm and surface tension σ = 25-37 mN / m. The dissolution of the aliphatic copolyamide is carried out with vigorous stirring and heating to a temperature of T = 60-105 ° C, followed by cooling to a temperature of T = 22-27 ° C, after which the obtained molding solution is electroformed at an electric field between the molding and precipitation electrodes E = from 50 to 110 kV and the distance between the forming and depositing electrodes L = from 100 to 170 mm. Moreover, the air humidity inside the chamber is from 30 to 60%, the air temperature in the chamber is from 21 to 28 ° C. Due to the provision of the indicated properties of the molding solution and the environment in which the nanofibers are formed, nanofibres with a diameter of 80-400 nm are obtained, which are deposited on a substrate material located directly below or above the precipitation electrode. In particular, a molding solution is prepared from aliphatic copolyamides dissolved in a mixture containing saturated monohydric alcohols and / or saturated mono-basic carboxylic acids. To obtain the required properties of the solution during the preparation of the molding solution, a sample of aliphatic copolyamide is placed in the required volume of solvent, calculated by the formula

$$\omega =\frac{m_{\mathrm{one}}}{{\mathrm{<figure-callout\; id="2"\; label="m"\; filenames="00000009.png,00000011.png"\; state="\{\{state\}\}">m</figure-callout>}}_2}\times \mathrm{one\; hundred}\%;{\mathrm{<figure-callout\; id="3"\; label="m"\; filenames="00000011.png,00000017.png"\; state="\{\{state\}\}">m</figure-callout>}}_3=m_2-m_{\mathrm{one}},$$

where m ₁ is the mass of copolyamide, g; m ₂ is the mass of the solution, g; m ₃ is the mass of solvent, g; ω is the mass concentration of copolyamide in solution,%.

To obtain a homogeneous solution, the mixing of the components of the molding solution is carried out, for example, using a magnetic stirrer or an overhead paddle mixer or rotary disperser, while the stirring speed is from 100 to 1000 rpm, and the operating time of the dispersant does not exceed 30 minutes. When heating the components of the molding solution, for example, electric or induction or microwave heating is used. Nanofibers from aliphatic copolyamide are obtained both by the capillary method of electrospinning and the capillary method of electrospinning, for example, according to the Nanospider technology. As a molding (working) electrode, in particular, a metal cylindrical electrode or a string electrode with the number of metal strings from 1 to 12 pieces is used. and provide a mold electrode rotation speed of 0.1 to 16 rpm. In addition, in the particular case, provide the speed of the substrate material adjacent to the precipitation electrode from 0.1 to 40 m / min. In addition, nanofibers are applied to the substrate material in a uniform layer with a specific gravity of from 0.01 to 65 g / m ² , and as the substrate material, for example, foil or synthetic non-woven material, or cellulose-paper material, or cellulosic material . In this case, a predetermined air humidity in the electroforming chamber can be achieved by pre-drying the supply air stream, a predetermined air temperature in the electroforming chamber can be achieved by pre-heating or cooling the supply air stream. In this case, nanofibers are applied in a uniform layer forming a nonwoven material, consisting of aliphatic copolyamide homogeneous in morphology and defect-free nanofibers. At the same time, in a particular case, it is taken into account that the molding solution must be stored before use under specified conditions, for example, at a temperature of 4 to 8 ° C without exposure to direct sunlight for no more than 2 months, and before the start of electroforming, the temperature of the molding solution is brought, in particular, up to a temperature of 22 to 27 ° C.

Thus, a non-woven material is obtained, consisting of nanofibers, having predetermined values of specific gravity, porosity, vapor and water permeability, bioinertness, adhesion. Fibers are non-toxic, have a developed specific surface area and the ability to deliver biologically active substances to body tissues, which allows their use in medicine. The resulting fibers and, accordingly, non-woven material from them can be used for the manufacture of wound dressings, dressings, filter material and a carrier of drugs.

The ability of polymers to fiber formation is determined by the following physicochemical properties of the polymer solution: viscosity, surface tension and electrical conductivity. Certain values of viscosity, surface tension and electrical conductivity should be consistent with each other and with the technological parameters of the installation for electrospinning. With various methods of forming fibers, the quality of the obtained fiber and the continuity of the fiber formation process depend on the physicochemical properties of the polymer and the solution, and the characteristics of the medium in the forming chamber.

The method is illustrated by the following graphic material.

Figure 1 presents SEM images (micrographs) of samples of non-woven material consisting of nanofibers obtained from a solution of the following composition: 50.0 g of polyamide, 385.0 g of ethanol, 95.0 g of distilled water. With values of E = 73 kV, L = 125 mm.

Figure 2 presents SEM images (micrographs) of samples of non-woven material based on nanofibers obtained from a solution of the following composition: 50.0 g of polyamide, 264.6 g of propanol, 113.4 g of isobutanol, 30.0 g of 99.8% acetic acid, 42.0 g of distilled water. At E = 73 kV, L = 125 mm. In this case, the viscosity of the resulting solution was η = 147 MPa · s, electrical conductivity 0 = 0.095 mS / cm.

Figure 3 presents SEM images (micrographs) of samples of a nonwoven fabric based on nanofibers obtained from a solution of the following composition: 2.5 g of polyamide, 368.4 g of isopropanol, 64.0 g of 99.8% acetic acid and 65.1 g of distilled water. At E = 73 kV, L = 125 mm. In this case, the viscosity of the resulting solution was significantly reduced and amounted to η = 67 MPa · s, and the specific conductivity was σ = 0.075 mS / cm.

Figure 4 presents SEM images (micrographs) of samples of a nonwoven fabric based on nanofibers obtained from a solution of the following composition: 175.0 g of polyamide, 300 g of isopropanol and 15.0 g of 99.8% acetic acid, 10.0 g of distilled water. At E = 65 kV, L = 130 mm. In this case, the viscosity of the resulting solution is significantly overestimated and amounted to a value greater than η = 900 MPa · s.

Figure 5 presents SEM images (micrographs) of samples of a nonwoven fabric based on nanofibers obtained from a solution of the following composition: 50.0 g of polyamide, 264.6 g of propanol, 113.4 g of isobutanol, 30.0 g of 99.8% acetic acid, 42.0 g of distilled water. The viscosity of the resulting solution was η = 147 mPa · s, electrical conductivity σ = 0.095 mS / cm, i.e. corresponding to the specified design physicochemical properties of the solution. With technological characteristics E = 73 kV and a reduced distance between the electrodes to L = 90 mm.

Figure 6 presents SEM images (micrographs) of samples of nonwoven fabric based on nanofibers obtained from a solution of the following composition: 50.0 g of polyamide, 264.6 g of propanol, 113.4 g of isobutanol, 30.0 g of 99.8% acetic acid, 42.0 g of distilled water. In this case, the viscosity of the resulting solution was η = 147 mPa · s, electrical conductivity σ = 0.095 mS / cm, i.e. corresponding to the specified design physicochemical properties of the solution. With technological characteristics: increased E = 120 kV and the same distance between the electrodes to L = 90 mm.

Figure 7 presents the dependence of the specific gravity (γ) of the material based on nanofibers on the speed (v) of the movement of the substrate material.

On Fig presents the dependence of the productivity of the process of electroforming nanofibers (P) on the value of relative humidity in the working chamber (RH).

Figure 1 shows SEM images (microphotographs) of samples of a nonwoven material consisting of nanofibers, from which it is seen that a significant number of defects are formed in the form of droplets with an electrostatic field voltage of 73 kV and a distance between electrodes of 125 mm, which is associated with the properties of the solvent, not having the required evaporation rate at the time of deposition of the fibers on the substrate material (Used a solution similar to the prototype).

Figure 2 shows SEM images (microphotographs) of samples of a nonwoven material consisting of nanofibers, from which it is seen that with the proposed physicochemical properties of the molding solution and with the same parameters of electrospinning, nanofibres with uniform morphology are obtained.

Figure 3 shows SEM images (microphotographs) of samples of a nonwoven material consisting of nanofibers, from which it is seen that when the viscosity of the molding solution decreases, fiber defects appear in the form of droplets and an uneven distribution of the nanofibers on the substrate material.

Figure 4 shows SEM images (microphotographs) of samples of a nonwoven material consisting of nanofibers, from which it is seen that with increasing viscosity of the molding solution, provided that the distance between the electrodes and the decrease in electrostatic voltage decrease, defects appear in the form of “bonding” of fibers and uneven distribution of nanofibers on the substrate material.

Figure 5 shows SEM images (microphotographs) of samples of a non-woven material consisting of nanofibers, from which it is seen that with the proposed physicochemical properties of the molding solution and with a decrease in the distance between the electrodes, fibers with a wide diameter distribution are obtained.

Figure 6 shows SEM images (microphotographs) of samples of a nonwoven material consisting of nanofibers, from which it is seen that with the proposed physicochemical properties of the molding solution and with increasing values of electrostatic voltage, nanofibres with a wide distribution in diameter but with uneven morphology are obtained .

Thus, the actual material confirms the achievement of improved quality of the obtained fiber by morphology, uniform distribution of fibers by diameter in the material based on the physicochemical properties of the molding solution and technological parameters of the electroforming agreed upon.

The claimed result on the possibility of using high-performance equipment is also confirmed by the above laws, which characterize the dependences indicated in Figs. 7 and 8, which demonstrate the dependence of the specific gravity of the material consisting of nanofibers on the feed rate of the substrate and the dependence of the productivity of the process of electroforming nanofibers on the relative humidity chamber for electroforming.

Thus, in the proposed invention, it is possible to continuously obtain nanofibers from a molding solution based on aliphatic copolyamides when using high-performance technological equipment for electroforming. At the same time, a non-woven material consisting of nanofibers is obtained, the properties and characteristics of which provide the desired purpose and function of the product, improving the quality of the obtained material from nanofibers by determining the optimal physicochemical properties of the molding solution and its modification.

Upon receipt of products from polyamides, including fibers, mainly melt technologies are used, because polyamides do not dissolve in most non-polar solvents - in hydrocarbons, esters, chlorine derivatives of hydrocarbons, while dissolving in highly polar solvents - phenol, cresol, chloral, trifluoroethanol, as well as formic, monochloracetic, trifluoroacetic acids. Typically, polyamides are used to produce adhesives, varnishes, prosthetic and orthopedic products, but melts or films obtained from solutions are traditionally used.

Mixed polyamides based on ε-caprolactam and salts of adipic acid (polyhexamethylene adipinamide), salts of sebacic acid (polyhexamethylene sebacinamide) in different proportions have good solubility in an aqueous-alcoholic medium, which allows them to be processed through the dissolution stage.

Fibers obtained from aqueous-alcoholic acidified solutions of aliphatic copolyamides by electrospinning do not contain solvent residues, which allows their use in medicine.

An inventive task is to determine the composition of a molding solution having optimal properties that ensure the continuity of the electroforming process to obtain defect-free fibers with a diameter of 80-400 nm. At the same time, it is required to ensure the use of this molding solution on high-performance technological equipment, in particular, by capillary-free electroforming using Nanospider technology.

It is known from the prior art that the physicochemical properties of polymer solutions, such as viscosity, electrical conductivity, surface tension, have a significant effect on the morphology of nanofibers. Therefore, it is required to provide a molding solution with desired physicochemical properties.

The invention is known "A method of obtaining a filter material, filter material, respiratory protection", patent RU 2248838, publ. 03/27/2005, IPC B01D 39/16, A62B 23/02, in which fibers are prepared by electrospinning from a molding solution of a styrene-acrylonitrile copolymer in an organic solvent in the presence of electrolytic additives. Based on this solution, a filter material is obtained from fibers of a styrene-acrylonitrile copolymer having increased mechanical strength. However, stabilization of the fiber production process is achieved by the addition of electrolytic additives, such as bromide or iodide salts of tetraethyl or tetrabutylammonium. In addition, the unbalanced properties of the viscous flow state of this solution do not allow the capless method to be used and do not provide the required ratio of the solution viscosity, its electrical conductivity and surface tension relative to the technological characteristics, which leads to significant defects in the resulting fiber.

Known invention "Spinning solution for electroforming", patent RU 2427673, publ. 08/27/2011, IPC D01D 1/02, D01D 5/00, in which silicon carbide fibers are obtained by electroforming a molding solution containing a 50-70% solution of polycarbosilane, which provides the necessary viscosity of the solution, a crosslinking agent and a photoinitiator. Such fibers can be used in the manufacture of high-temperature filtering and insulating materials, but are not acceptable for medical dressings.

The closest in essence and the achieved result is the invention "A method for producing nanofibers from aliphatic copolyamides by electrospinning", patent RU 2447207, publ. 04/10/2012, IPC D01F 6/80, B82B 3/00, in which nanofibers are obtained from aliphatic copolyamides by electrospinning, and the dependences of the structure of nanofibers on the concentration of the copolyamide solution and the electric field strength are established. In this case, waterproof fibers are obtained using an environmentally friendly solvent.

However, only water-ethanol mixtures are used as a solvent at various ratios of components, which leads to phase separation, cannot ensure the continuity of the electroforming process at room temperature, the optimal physicochemical properties of the molding solution and the quality of the obtained nanofibers on the precipitation electrode. In addition, the composition of the molding solution cannot be used with the capless method of electroforming.

The proposed composition of the molding solution takes into account all the requirements for the physicochemical properties of the molding solution in relation to the technological parameters of the electroforming process.

The claimed technical result is achieved due to the fact that using the composition of the molding solution for the method according to claim 1, above, and including polymers and a solvent. In the molding solution, an aliphatic copolyamide obtained as a result of copolymerization of ε-caprolactam with an adipic acid salt (polyhexamethylene adipinamide), copolymerization of ε-caprolactam with an adipic acid salt (polyhexamethylene adipinamide) and a sebacic acid salt (polyhexamene ratio) is used as a polymer as a solvent, a mixture of saturated monohydric alcohols and / or saturated monobasic carboxylic acids, which are organic Oritel.

The composition of the molding solution is characterized by the following ratio of components of the total amount of solution, wt.%:

- aliphatic copolyamide 1-30

- solvent 30-90

- the rest is distilled water.

Moreover, the composition of the molding solution for the above method according to claim 1 may include, as a polymer, an aliphatic copolyamide obtained by copolymerization of ε-caprolactam with a salt of adipic acid (polyhexamethylene adipinamide), copolymerization of ε-caprolactam with a salt of adipic acid (polyhexamethylene adipinamide) and with a sebaci salt acids (polyhexamethylene sebacinamide) in arbitrary proportions of components, and as a solvent, a water-alcohol mixture containing saturated monohydric alcohols and e monobasic carboxylic acids, in the following ratio of components of the total amount of solution, wt.%:

- aliphatic copolyamide 5-30

- acid 1 ÷ 30

- alcohol 30-90

- the rest is distilled water.

In another embodiment, the composition of the molding solution for the method according to claim 1, may include, as a polymer, an aliphatic copolyamide obtained by copolymerization of ε-caprolactam with a salt of adipic acid (polyhexamethylene adipinamide), copolymerization of ε-caprolactam with a salt of adipic acid (polyhexamethylene adipinamide) and salt of sebacic acid (polyhexamethylene sebacinamide) in arbitrary proportions of components, and as a solvent, an aqueous-acidic mixture containing saturated monobasic carboxylic acids, etc. and the following ratio of components from the total amount of solution, wt.%:

- aliphatic copolyamide 1-30

- acid 50-80

- the rest is distilled water.

In special cases, use:

- as an aliphatic copolyamide use copolyamide PA 6 / 66-3 or copolyamide PA 6 / 66-4 with a concentration of 5-30 wt.%. The solvent used is a mixture of an aqueous solution of n-propanol with a concentration of 80 wt.% And acetic or formic acid with a concentration of 2-20 wt.%;

- as an aliphatic copolyamide use copolyamide PA 6 / 66-3 or copolyamide PA 6 / 66-4 with a concentration of 5-30 wt.%. The solvent used is a mixture of an aqueous solution of n-propanol with a concentration of 70 wt.% And acetic or formic acid with a concentration of 1-10 wt.%;

- as an aliphatic copolyamide use copolyamide PA 6 / 66-3 or copolyamide PA 6 / 66-4 with a concentration of 10-30 wt.%. The solvent used is a mixture of an aqueous solution of n-propanol with a concentration of 60 wt.% And acetic or formic acid with a concentration of 12-17 wt.%;

- as an aliphatic copolyamide use copolyamide PA 6 / 66-3 or copolyamide PA 6 / 66-4 with a concentration of 5-30 wt.%. The solvent used is a mixture of an aqueous solution of n-propanol with a concentration of 50 wt.% And acetic or formic acid with a concentration of 14-30 wt.%;

- as an aliphatic copolyamide use copolyamide PA 6/66 / 610-5 with a concentration of 5-30 wt.%. The solvent used is a mixture of an aqueous solution of n-propanol with a concentration of 80 wt.% And acetic or formic acid with a concentration of 5-30 wt.%, And a mixture of n-propanol and isobutanol in a ratio of 70/30 ÷ 40/60, respectively, and 5 -30 wt.% Acetic or formic acid, the rest is distilled water;

- n-propanol, and / or isopropanol, and / or n-butanol, and / or sec-butanol, and / or isobutanol or tert-butanol are used as the main solvent to obtain the water-alcohol mixture;

- as the aliphatic copolyamide use copolyamide PA 6 / 66-3 or copolyamide PA 6 / 66-4 or copolyamide PA 6/66 / 610-5 with a concentration of 1-30 wt.%. As a solvent, an aqueous solution of acetic or formic acid with a concentration of 50-80% is used.

The indicated compositions of the molding solution are correlated in their physicochemical properties with technological parameters that ensure the continuity of the electroforming process and the production of defect-free nanofibers, as described above.

The drawings show the dependence of the changes in the physicochemical properties of polymer solutions on the concentration of components and their molecular weight.

Figure 9 shows the change in viscosity (η) of solutions with increasing concentration (ω) of the polymer. Curves 1, 2, and 3 correspond to polymers of different molecular weights; molecular weight decreases from curve 1 to curve 3.

Figure 10 shows the change in surface tension (σ) of solutions with increasing concentration (ω) of the polymer.

11 shows the change in surface tension (σ) of solutions with increasing viscosity (η) of solutions.

On Fig shows the change in the diameter (d) of the fibers with increasing viscosity (η) of the molding solution.

On Fig shows the change in surface tension of solutions of n-propanol. Thus, the ratio of the components in the molding solution was correlated with the parameters of the electroforming process with a satisfactory result. It was shown that: 1 - an aqueous solution, 2 - a solution of n-propanol in isobutyl alcohol, ω,% - mass percentage of n-propanol.

On Fig shows the change in electrical conductivity of aqueous solutions of n-propanol - 1 and isopropanol - 2. ω,% mass percent alcohol in the solution.

On Fig shows the dependence of surface tension (σ, mN / m) of aqueous solutions of n-propanol (a) and isopropanol (b) with an alcohol concentration of 1-50%, 2-60%, 3-70%, 4-80 % of the concentration of acetic acid in solution. ω,% - mass percentage of acid in an aqueous-alcoholic solution.

On Fig shows the dependence of surface tension (σ, mN / m) of solutions of n-propanol in isobutanol with a concentration of n-propanol: 1-50%, 2-60%, 3-70%, 4-80% of the concentration of acetic acid in solution, ω,% - mass percentage of acid in the solution.

On Fig shows the dependence of the electrical conductivity of aqueous solutions of n-propanol with an alcohol concentration of 1-50%, 2-60%, 3-70%, 4-80% of the concentration of acetic acid in the solution, ω,% - mass percentage acids in a water-alcohol solution.

On Fig shows the dependence of the surface tension of water-alcohol solutions of copolyamide on the concentration of acetic acid. ω,% - mass percentage of acid in an aqueous-alcoholic solution.

The presented solution is prepared as follows.

1. For the preparation of water-alcohol solutions of PA 6/66 / 610-5, a concentration of 5%.

Example 1. A portion of a copolyamide weighing 25.0 g was added to a solvent mixture consisting of 400.0 g of propanol, 25.0 g of 99.8% acetic acid and 50.0 g of distilled water. Intensively mixed on a magnetic stirrer while heating 60 ÷ 105 ° C. Next, the solution was kept at room temperature until completely cooled.

Example 2. A portion of a copolyamide weighing 25.0 g was added to a solvent mixture consisting of 350.0 g of propanol, 5.0 g of 99.8% formic acid and 120.0 g of distilled water. Intensively mixed on a magnetic stirrer while heating 60 ÷ 105 ° C. Next, the solution was kept at room temperature until completely cooled.

2. For the preparation of water-alcohol solutions of PA 6/66 / 610-5, concentration of 30%.

Example 3. A portion of copolyamide weighing 150.0 g was added to a solvent mixture consisting of 242.0 g of propanol, 76.0 g of isobutanol, 30.0 g of 99.8% acetic acid. Intensively mixed on a magnetic stirrer while heating 60 ÷ 105 ° C. Next, the solution was kept at room temperature until completely cooled.

Example 4. A portion of a copolyamide weighing 150.0 g was added to a solvent mixture consisting of 214.6 g of propanol, 63.4 g of isobutanol, 30.0 g of 99.8% acetic acid and 42.0 g of distilled water. Intensively mixed on a magnetic stirrer while heating 60 ÷ 105 ° C. Next, the solution was kept at room temperature until completely cooled.

3. For the preparation of water-alcohol solutions of PA 6 / 66-3 and PA 6 / 66-4 with a concentration of 5%.

Example 5. A portion of copolyamide weighing 25.0 g was added to a solvent mixture consisting of 297.5 g of propanol, 127.5 g of water, 50.0 g of 99.8% acetic acid. Intensively mixed on a magnetic stirrer while heating 60 ÷ 105 ° C. Next, the solution was kept at room temperature until completely cooled.

Example 6. A portion of a copolyamide weighing 25.0 g was added to a solvent mixture consisting of 315.0 g of propanol, 135.0 g of water, 25.0 g of 99.8% formic acid. Intensively mixed on a magnetic stirrer while heating 60 ÷ 105 ° C. Next, the solution was kept at room temperature until completely cooled.

4. For the preparation of water-alcohol solutions of PA 6 / 66-3 and PA 6 / 66-4 with a concentration of 30%.

Example 7. A portion of a copolyamide weighing 150.0 g was added to a solvent mixture consisting of 235.0 g of propanol, 65.0 g of water, 50.0 g of 99.8% acetic acid. Intensively mixed on a magnetic stirrer while heating 60 ÷ 105 ° C. Next, the solution was kept at room temperature until completely cooled.

Example 8. A portion of a copolyamide weighing 150.0 g was added to a solvent mixture consisting of 252.5 g of isopropanol, 72.5 g of water, 25.0 g of 99.8% formic acid. Intensively mixed on a magnetic stirrer while heating 60 ÷ 105 ° C. Next, the solution was kept at room temperature until completely cooled.

5. For the preparation of aqueous acidic solutions of PA 6 / 66-3, PA 6 / 66-4 and PA 6/66 / 610-5 with a concentration of 1%.

Example 9. A weighed portion of copolyamide weighing 5.0 g was added to a solvent mixture consisting of 240.0 g of water, 255.0 g of 99.8% acetic acid. Intensively mixed on a magnetic stirrer while heating 60 ÷ 105 ° C. Next, the solution was kept at room temperature until completely cooled.

6. For the preparation of aqueous-acidic solutions of PA 6 / 66-3, PA 6 / 66-4 and PA 6/66 / 610-5 with a concentration of 30%.

Example 10. A portion of copolyamide weighing 150.0 g was added to a solvent mixture consisting of 75.0 g of water, 275.0 g of 99.8% formic acid. Intensively mixed on a paddle stirrer while heating 60 ÷ 105 ° C. Next, the solution was kept at room temperature until completely cooled.

The properties of this molding solution with the claimed composition of the components are confirmed by actual studies.

Thus, the presented solution compositions provide the necessary physicochemical properties of the molding solution suitable for electrospinning.

In this case, the compositions of the solutions in general are prepared as follows. A portion of the copolyamide is placed in the required amount of solvent, intensively mixed on a mixer with heating at 60 ÷ 105 ° C. Next, the solutions are kept at room temperature up to 22-27 ° C. The calculation of the mass of the components is carried out based on the concentration of copolyamide according to the above formula.

The copolyamide solvents were aqueous solutions of propanol and isopropanol, to which acetic (or formic) acid was added; a mixture of n-propanol and isobutanol alcohols, to which acetic (or formic) acid or only one acid was added.

Thus, the compositions of the solutions and their properties, as well as the parameters of the electroforming process, were verified with an increase in the concentration of copolyamide in the solution from 1 to 30% with a diameter of the resulting nanofibers from 100 to 400 nm.

On Fig and 14 presents the changes in the properties of water-alcohol solutions.

On Fig-17 presents the changes in the properties of water-alcohol solutions and a mixture of n-propanol / isobutanol with the addition of acetic acid.

On Fig presents changes in the surface tension of copolyamide solutions.

With an increase in the concentration of copolyamide and acetic acid, the surface tension of the solution increases. A similar view will have a graph of the change in the conductivity of the solution.

When using formic acid, the appearance of the curves on the graph will be the same.

In this case, the compositions of the solutions in general are prepared as follows. A portion of the copolyamide is placed in the required amount of solvent, intensively mixed on a mixer with heating at 60 ÷ 105 ° C. Next, the solutions are kept at room temperature up to 22-27 ° C. The calculation of the mass of the components is based on the concentration of copolyamide according to the above formula.

Thus, the compositions of the solutions and their properties, as well as the parameters of the electroforming process, were verified with an increase in the concentration of copolyamide in the solution from 5 to 30% with a diameter of the resulting nanofibers from 200 to 400 nm.

Thus, the ratio of the components in the molding solution was correlated with the parameters of the electroforming process with a satisfactory result.

The results are shown in the table.

Table 1 Solvent composition The concentration of SPA, wt.% Solution properties Electroforming process parameters η, MPa · s æ, mS / cm σ, mN / m HV, kB L mm RH% Copolyamide PA 6 / 66-3 80-50 wt.% Aqueous solution of n-propanol, 2-20 wt.% Acetic acid (or formic acid) 5-30 300-700 0.04-0.25 25.6-34 60-75 120-140 30-40 50-80 wt.% Aqueous solution of acetic (or formic) acid 1-30 200-800 0.15-0.25 31, -36.4 60-75 120-140 30-40 Copolyamide PA 6 / 66-4 80-50 wt.% Aqueous solution of n-propanol, 2-20 wt.% Acetic acid (or formic acid) 5-30 300-700 0.04-0.25 25.7-28 60-75 120-140 30-40 50-80 wt.% Aqueous solution of acetic (or formic) acid 1-30 200-800 0.14-0.22 30.5-37 60-75 120-140 30-40 Copolyamide PA 6/66 / 610-5 80 wt.% Aqueous solution of n-propanol, 2-20 wt.% Acetic acid (or formic acid) 5-30 100-400 0.5-0.1 25.5-31 60-75 120-140 30-40 A mixture of n-propanol / isobutanol in a ratio of 80 / 20-40 / 60, 2-20 wt.% Acetic acid (or formic acid) 5-30 100-400 0.08-0.19 26,4-30 60-75 120-140 30-40 50-80 wt.% Aqueous solution of acetic (or formic) acid 1-30 100-400 0.13-0.21 32.4-36.7 60-75 120-140 30-40

Based on the task, it is necessary to ensure the production of material from nanofibers, the physicochemical properties of which simultaneously provide the required function of the material, for example, porosity, vapor permeability, sorption, elasticity, biodegradability, antibacterial activity.

The properties of solutions from polyamides, in particular from aliphatic copolyamides, can be changed by introducing antiseptic, coloring additives, impact modifiers, hydrophobic additives, mineral fillers, and other polymers into the solution.

Depending on the selected modifier, it is possible to give the resulting nonwoven material the necessary properties, for example biodegradability and non-toxicity.

In particular, nanoparticles of d-element compounds, or additives that modify the copolymer by adding a polymer, for example a polysaccharide, can be used as modifying additives.

In this case, the physicochemical properties of the modified molding solution will be maintained to ensure the production of high quality fibers.

By adding modifying additives, a smaller nanofiber diameter of up to 80 nm can be achieved.

The invention is known "Biopolymer fiber, the composition of the molding solution for its production", patent RU 2468129, publ. 07/10/2012, IPC D01F 4/00, A61L 15/22, A61L 15/28, in which biologically active substances of antiseptic, disinfectant, anti-inflammatory or topical anesthetic or antibacterial and bacteriostatic or proteolytic or hemostatic effects are used as additives . However, this solution does not meet the requirements of a continuous process of electroforming with obtaining non-woven material consisting of nanofibers with uniform morphology and uniform distribution in diameter.

The invention is known "Heat-resistant polymer nanocomposite with bright photoluminescence", patent RU 2434045, publ. 11/20/2011, IPC C09K 11/08, B82B 1/00, in which, to produce heat-resistant (co) polymer nanocomposites with bright photoluminescence, at the stage of synthesis, preparation of a composition, or molding an article, a nanoscale is introduced into the (co) polymer as a light-converting component silicon. This composite refers to polymeric nanocomposites that convert the UV component of a solar or other light source into the radiation of the visible part of the spectrum, but it is not suitable for electroforming.

The invention is known "Porous biodegradable material based on natural polysaccharides", application RU 2010110037, publ. 09/27/2011, IPC A61K 31/722, C08B 37/08, C08L 5/08, C08J 9/00, to which functional additives are added to give antiseptic properties: metal nanoparticles, but only polysaccharide solutions are used for modification.

Closest to the proposed invention relates to the invention "A method for hydrophilic textile materials with antimicrobial properties", patent RU 2456995, publ. 07/27/2012, IPC A61K 33/38, A61L 15/46, A01N 59/00, B82B 3/00, in which nanostructured silver particles are added to modify hydrophilic textile materials and products from them in order to increase the stability of the antimicrobial effect. However, the processing is carried out directly by the material itself, and not the solution, and this method does not use fibers obtained by electrospinning.

The claimed technical result is due to the following method of modifying nanofibers obtained by the above method. Previously, in the process of preparing the molding solution with the composition of the molding solution mentioned above, d-element compounds or polysaccharides or antiseptic substances are added, and then electroforming is carried out to obtain a non-woven material formed by modified nanofibres of aliphatic copolyamide. The novelty of the method lies in the fact that to give antibacterial properties to nanofibers obtained by electrospinning, for example, in the process of preparing a molding solution, a colloidal aqueous solution of nanosized particles of d-elements is added in the following ratio of components of the total amount of solution, wt.%:

molding solution according to claim 3 - from 90 to 99.9

colloidal aqueous solution of nanoscale particles of d-elements from 0.1 to 10,

or as a colloidal aqueous solution of nanoscale particles of d-elements, a colloidal aqueous solution of silver nanoparticles with a diameter of not more than 70 nm is used. In the particular case, also for the use of nanofibers in medicine for various skin diseases, an antiseptic substance is used as a modifying additive in the form of a triphenylmethane derivative, in the following ratio of components of the total amount of solution, wt.%:

molding solution according to claim 2 - 85-99.9

derivative of triphenylmethane series - 0.1-15.

In the particular case of fiber modification, a tetraethyl-4,4-diaminotriphenylmethane salt is used as an antiseptic.

In order to obtain biodegradable nonwoven materials based on nanofibers from aliphatic polyamides, they are modified, for example, with polysaccharides. For example, in the process of preparing the molding solution according to claim 20, an aqueous polysaccharide solution is added in the following ratio of components of the total amount of solution, wt.%:

molding solution according to claim 3 - 10-60

polysaccharide solution - 40-90.

For example, an aqueous solution of poly-N-acetyl-1,4-β-D-glucosamine is used as an aqueous solution of a polysaccharide.

This modification can significantly improve the biodegradation of the nonwoven material based on nanofibres of aliphatic copolyamide.

This method is as follows.

The nanofibers were modified with silver nanoparticles 3-16 nm in size or with tetraethyl-4,4-diaminotriphenylmethane salt, as well as with an aqueous solution of poly-N-acetyl-1,4-β-D-glucosamine. The modification method consists in adding a colloidal aqueous solution of silver metal nanoparticles or a salt of tetraethyl-4,4-diaminotriphenylmethane or an aqueous solution of poly-N-acetyl-1,4-β-D-glucosamine to the finished molding copolyamide solution.

The method is illustrated in table 2. In the table, column number 1 is the addition of a colloidal aqueous solution of silver nanoparticles, column number 2 is the addition of tetraethyl-4,4-diaminotriphenylmethane, column number 3 is the addition of an aqueous solution of poly-N-acetyl-1,4 β-D-glucosamine.

table 2 Solvent composition The concentration of SPA, wt.% The concentration of additives, wt.% Electroforming process parameters σ, mN / m HV, kV L mm RH% one 2 3 Copolyamide PA 6 / 66-3 80-50 wt.% Aqueous solution of n-propanol, 2-17 wt.% Acetic acid (or formic acid) 5-30 0,1-10 0,1-10 - 23.1-28.7 70-75 120-130 30-36 50-60 wt.% Aqueous solution of acetic (or formic) acid 1-10 - - 40 32-36 70-75 120-130 30-36 Copolyamide PA 6 / 66-4 80-50 wt.% Aqueous solution of n-propanol, 2-17 wt.% Acetic acid (or formic acid) 5-30 0,1-10 0.1-15 - 24.2-29.4 70-75 120-130 30-36 50-60 wt.% Aqueous solution of acetic (or formic) acid 1-10 - - 40 31.1-35.2 70-75 120-130 30-36 Copolyamide PA 6/66 / 610-5 80 wt.% Aqueous solution of n-propanol, 2-20 wt.% Acetic acid (or formic acid) 5-30 0,1-10 0.1-15 - 24.4-31.2 70-75 120-130 30-36 A mixture of n-propanol / isobutanol in a ratio of 80 / 20-40 / 60, 2-20 wt.% Acetic acid (or formic acid) 5-30 0,1-10 0.1-15 - 25.2-29.8 70-75 120-130 30-36 50-80 wt.% Aqueous solution of acetic (or formic) acid 1-30 - - 40 31.7-35.8 70-75 120-130 30-36

From table 2 it is seen that the nanofibers were modified with silver nanoparticles or an antiseptic substance in order to give the material antibacterial properties, as well as with a polysaccharide in order to improve the biodegradation of non-woven material based on nanofibres from aliphatic copolyamide. The modification method consists in adding a colloidal aqueous solution of metal nanoparticles or an antiseptic substance or an aqueous solution of a polysaccharide to the finished molding solution of copolyamide. In this case, the additive affects only the surface tension of the solution, all other properties of the solution — viscosity and electrical conductivity and parameters of the electroforming process remain unchanged. The diameter of the obtained fibers is reduced by 50-100 nm in comparison with the fibers obtained from solutions without modifying additives.

An example of the preparation of a solution with an addition in the form of silver nanoparticles with a concentration

A portion of copolyamide weighing 60.0 g was added to a solvent mixture consisting of 278.7 g of propanol, 112.7 g of isobutanol, 22.0 g of 99.8% acetic acid. Intensively mixed on a magnetic stirrer while heating 60 ÷ 105 ° C until complete dissolution of the copolyamide. Next, 25 g of an aqueous colloidal solution of silver metal nanoparticles was added to the solution and stirred for 1-1.5 hours on a magnetic stirrer. The solution was kept at room temperature up to 22-27 ° C, after which the electroforming process was started.

An example of the preparation of a solution with the addition of tetraethyl-4,4-diaminotriphenylmethane

A portion of a copolyamide weighing 150 g was added to a solvent mixture consisting of 200 g of isopropanol, 50.0 g of 99.8% acetic acid and 100 g of distilled water. Intensively mixed on a magnetic stirrer while heating 60 ÷ 105 ° C until complete dissolution of the copolyamide. Then, 10 g of tetraethyl-4,4-diaminotriphenylmethane salt was added to the solution and stirred for 1-1.5 hours on a magnetic stirrer. The solution was kept at room temperature up to 22-27 ° С, after which the electroforming process was started.

An example of the preparation of a solution with the addition of poly-N-acetyl-1,4-β-D-glucosamine

A weighed portion of copolyamide weighing 20.0 g was added to a solvent mixture consisting of 92.5 g of water, 137.5 g of 99.8% acetic acid. Intensively mixed on a magnetic stirrer while heating 60 ÷ 105 ° C. Next, the solution was kept at room temperature until completely cooled. Then an aqueous solution of poly-N-acetyl-1,4-β-D-glucosamine was added in an amount of 375 g and stirred on a magnetic stirrer for 1-1.5 hours. The solution was kept at room temperature to 22-25 ° C, after which started the process of electroforming.

Examples show that when modifying the molding solution, it is possible to obtain not only single-component fibers, but also two-three-component ones. At the same time, the properties of the material expand significantly, it acquires antiseptic properties and biodegradability.

Thus, the proposed technical solution on the actual material offers a solution to the problem. Therefore, the presented graphs and tables of the ratios of the physicochemical properties of the molding solution and the parameters of the electroforming process are sufficient to satisfactorily obtain a technical result.

Thus, a non-woven material consisting of nanofibers obtained by the proposed method from the above solutions, including modified ones, can be widely used not only in medicine, but also in the filtration of air and aqueous media, the manufacture of protective textile materials, as well as drug carriers preparations.

Claims (32)

1. A method of producing nanofibers from aliphatic copolyamides by electroforming, including the conversion of an aliphatic copolyamide into a viscous flow state by preparing a molding solution with predetermined physicochemical properties, ensuring the continuity of the process of producing nanofibers, by the method of electroforming and electrospinning of nanofibers from the obtained molding solution, characterized in that as a result dissolving aliphatic copolyamides in an aqueous-organic mixture with weak acidic properties get a molding solution with the following physicochemical properties: dynamic viscosity η = 100-800 mPa · s, electrical conductivity æ = 40-250 μS / cm and surface tension σ = 25-37 mN / m, while the aliphatic copolyamide is dissolved at vigorous stirring and heating to a temperature of T = 60-105 ° C, followed by cooling to a temperature of T = 22-27 ° C, after which the obtained molding solution is electroformed at an electric field voltage between the spinning electrode and the precipitation electrode E = from 50 d 110 kV and the distance between the spinning and precipitating electrodes L = from 100 to 170 mm, and the air humidity inside the electrospinning chamber is from 30 to 60%, the air temperature in the electrospinning chamber is from 21 ° C to 28 ° C, get nanofibers with a diameter of 80- 400 nm on a substrate material located directly above the precipitation electrode. 2. The method of producing nanofibers according to claim 1, characterized in that the molding solution is obtained from aliphatic copolyamides dissolved in a mixture containing saturated monohydric alcohols and / or saturated monobasic carboxylic acids. 3. The method of producing nanofibers according to claim 1, characterized in that during the preparation of the molding solution, a weighed portion of aliphatic copolyamide is placed in the required volume of solvent, calculated by the formula
$$\omega =\frac{m_{\mathrm{one}}}{m_2}\times \mathrm{one\; hundred}\%;m_3=m_2-m_{\mathrm{one}},$$

where m ₁ is the mass of copolyamide, g; m ₂ is the mass of the solution, g; m ₃ is the mass of solvent, g; ω is the mass concentration of copolyamide in solution,%. 4. The method of producing nanofibers according to claim 1, characterized in that the mixing of the components of the molding solution is carried out using a magnetic stirrer, or overhead paddle mixer, or rotary disperser, while the mixing speed is from 100 to 1000 rpm, and the operating time of the dispersant does not exceed 30 minutes 5. The method of producing nanofibers according to claim 1, characterized in that when heating the components of the molding solution, electric, or induction, or microwave heating is used. 6. The method of producing nanofibers according to claim 1, characterized in that the nanofibers from aliphatic copolyamide are obtained by capillary electrospinning. 7. The method of producing nanofibers according to claim 1, characterized in that the nanofibers from aliphatic copolyamide are obtained by capillary-free electroforming using Nanospider technology. 8. The method of producing nanofibers according to claim 7, characterized in that a metal cylindrical electrode or a string electrode with a number of metal strings from 1 to 12 pcs is used as a spinning electrode. 9. The method of producing nanofibers according to claim 7, characterized in that the spinning electrode rotates at a speed of 0.1 to 16 rpm. 10. The method of producing nanofibers according to claim 1, characterized in that they provide a speed of movement of the substrate material adjacent to the precipitation electrode, from 0.1 to 40 m / min 11. The method of producing nanofibers according to claim 1, characterized in that the nanofibers are obtained on the substrate material in a cured state. 12. The method of producing nanofibers according to claim 1, characterized in that a predetermined humidity in the electroforming chamber is achieved by pre-drying the supply air stream. 13. The method of producing nanofibers according to claim 1, characterized in that the predetermined temperature of the air in the electrospinning chamber is achieved by pre-heating or cooling the supply air stream. 14. The method of producing nanofibers according to claim 1, characterized in that the molding solution is stored until use at a temperature of 4 to 8 ° C without exposure to direct sunlight for no more than 2 months. 15. The method of producing nanofibers according to any one of claims 1 to 14, characterized in that before starting the electroforming, the temperature of the molding solution is brought to a temperature of 22 to 27 ° C. 16. The composition of the molding solution for the method according to claim 1, comprising polymers and a solvent, where the polymer is an aliphatic copolyamide obtained by copolymerization of ε-caprolactam with a salt of adipic acid (polyhexamethylene adipinamide), copolymerization of ε-caprolactam with a salt of adipic acid (polyhexamethylene adipinamide ) and with a salt of sebacic acid (polyhexamethylene sebacinamide) in arbitrary proportions of components, and an aqueous mixture of saturated monohydric alcohols and / or specific monobasic carboxylic acids in the following ratio of components of the total amount of solution, wt.%:
- aliphatic copolyamide 1-30
- solvent 30-90
- the rest is distilled water. 17. The composition of the molding solution according to clause 16 for the method according to claim 1, comprising polymers and a solvent, wherein the polymer is an aliphatic copolyamide obtained by copolymerization of ε-caprolactam with a salt of adipic acid (polyhexamethylene adipinamide), copolymerization of ε-caprolactam with a salt adipic acid (polyhexamethylene adipinamide) and with the salt of sebacic acid (polyhexamethylene sebacinamide) in arbitrary proportions of the components, and a water-alcohol mixture containing limit monohydric alcohols and saturated monobasic carboxylic acids, in the following ratio of components of the total amount of solution, wt.%:
- aliphatic copolyamide 5-30
- acid 1-30
- alcohol 30-90
- the rest is distilled water. 18. The composition of the molding solution according to clause 16 for the method according to claim 1, comprising polymers and a solvent, wherein the polymer is an aliphatic copolyamide obtained by copolymerization of ε-caprolactam with an adipic acid salt (polyhexamethylene adipinamide), copolymerization of ε-caprolactam with a salt adipic acid (polyhexamethylene adipinamide) and with the salt of sebacic acid (polyhexamethylene sebacinamide) in arbitrary proportions of the components, and as a solvent use an aqueous acid mixture containing limit monobasic carboxylic acids, in the following ratio of components of the total amount of solution, wt.%:
- aliphatic copolyamide 1-30
- acid 50-80
- the rest is distilled water. 19. The composition of the molding solution according to clause 16 for the method according to claim 1, characterized in that as the aliphatic copolyamide use copolyamide PA 6 / 66-3 or copolyamide PA 6 / 66-4 with a concentration of 5-30 wt.%, the solvent used is a mixture of an aqueous solution of n-propanol with a concentration of 80 wt.% and acetic or formic acid with a concentration of 2-20 wt.%. 20. The composition of the molding solution according to 17 for the method according to claim 1, characterized in that as the aliphatic copolyamide use copolyamide PA 6 / 66-3 or copolyamide PA 6 / 66-4 with a concentration of 5-30 wt.%, the solvent used is a mixture of an aqueous solution of n-propanol with a concentration of 70 wt.% and acetic or formic acid with a concentration of 1-10 wt.%. 21. The composition of the molding solution according to 17 for the method according to claim 1, characterized in that as the aliphatic copolyamide use copolyamide PA 6 / 66-3 or copolyamide PA 6 / 66-4 with a concentration of 10-30 wt.%, the solvent used is a mixture of an aqueous solution of n-propanol with a concentration of 60 wt.% and acetic or formic acid with a concentration of 12-17 wt.%. 22. The composition of the molding solution according to 17 for the method according to claim 1, characterized in that as the aliphatic copolyamide use copolyamide PA 6 / 66-3 or copolyamide PA 6 / 66-4 with a concentration of 5-30 wt.%, the solvent used is a mixture of an aqueous solution of n-propanol with a concentration of 50 wt.% and acetic or formic acid with a concentration of 14-30 wt.%. 23. The composition of the molding solution according to claim 17 for the method according to claim 1, characterized in that the copolyamide PA 6/66 / 610-5 with a concentration of 5-30 wt.% Is used as an aliphatic copolyamide, an aqueous solution of a mixture is used n-propanol with a concentration of 80 wt.% and acetic or formic acid with a concentration of 5-30 wt.%, and a mixture of n-propanol and isobutanol in a ratio of 70 / 30-40 / 60, respectively, and 5-30 wt.% acetic or formic acid, the rest is distilled water. 24. The composition of the molding solution according to claim 17 for the method according to claim 1, characterized in that n-propanol and / or isopropanol and / or n-butanol and / or sec-butanol and / or isobutanol or tert-butanol. 25. The composition of the molding solution according to p. 18 for the method according to claim 1, characterized in that as the aliphatic copolyamide use copolyamide PA 6 / 66-3, or copolyamide PA 6 / 66-4, or copolyamide PA 6/66/610 -5 with a concentration of 1-30 wt.%, An aqueous solution of acetic or formic acid with a concentration of 50-80% is used as a solvent. 26. The method of modifying the nanofibers obtained by the method according to claim 1, characterized in that first, during the preparation of the molding solution according to claim 17, d-element compounds, or polysaccharides, or antiseptic or dyes are added, after which modified aliphatic copolyamide nanofibers are obtained electroforming method. 27. The modification method according to p. 26 of the nanofibers obtained by the method according to claim 1, characterized in that first, in the process of preparing the molding solution according to clause 16, add a colloidal aqueous solution of nanosized particles of d-elements in the following ratio of components from the total amount of solution, wt.%:
molding solution according to claim 3 - from 90 to 99.9
colloidal aqueous solution of nanoscale particles of d-elements from 0.1 to 10. 28. The modification method according to claim 27 of the nanofibers obtained by the method according to claim 1, characterized in that a colloidal aqueous solution of silver nanoparticles with a diameter of not more than 70 nm is used as a colloidal aqueous solution of nanoscale particles of d-elements. 29. The modification method according to p. 26 of the nanofibers obtained by the method according to claim 1, characterized in that when receiving the molding solution add an antiseptic substance in the form of a triphenylmethane derivative in the following ratio of components of the total amount of solution, wt.%:
molding solution according to claim 2 - 85-99.9
derivative of triphenylmethane series - 0.1-15. 30. The modification method according to clause 29 of the nanofibers obtained by the method according to claim 1, characterized in that a tetraethyl-4,4-diaminotriphenylmethane salt is used as a triphenylmethane derivative. 31. The modification method according to p. 26 of the nanofibers obtained according to claim 1, characterized in that during the preparation of the molding solution according to p. 18 add an aqueous solution of the polysaccharide in the following ratio of components of the total amount of solution, wt.%:
molding solution according to claim 3 - 10-60
polysaccharide solution - 40-90. 32. The modification method according to p. 31 of the nanofibers obtained according to claim 1, characterized in that an aqueous solution of poly-N-acetyl-1,4-β-D-glucosamine is used as an aqueous solution of the polysaccharide.

Images