TECHNICAL FIELD

The group of inventions relates to the field of fabric industry, in particular, to special- purpose materials, characterized by high vapor permeability and water resistance, at low air permeability, and can be applied in the production of sportswear, as well as various types of specialized clothing.

PRIOR ART

The prior art discloses methods for producing textile materials of miscellaneous purpose. For example, known is a method for producing a porous material (patent US4127706 for the invention“Porous fluoropolymeric fibrous sheet and method of manufacture”, publ. 28.11.1978), which includes preparing a forming solution based on fluorinated polymers (in particular, polytetrafluoroethylene) and electroforming fibres from the resulting solution.

The disadvantage of the described method is that the used forming solution based on polytetrafluoroethylene has a high viscosity. Therefore, drawing-out fibres from such a solution is rather challenging, which results to the formation of a non-homogeneous structure, non-uniform over its thickness. This causes low water resistance and high air permeability of the fibrous material.

Known is a method for producing a membrane material, a forming solution for its implementation and a membrane material, designed to be used in chemical, food and pharmaceutical industry (patent US6126826 for the invention“PVDF microporous membrane and method”, publ. 03.10.2000). The method includes preparing a forming solution by dissolving polyvinylidenefluoride in solvents (dimethylformamide and ethylacetoacetate), dispersing the resulting solution on a solid surface to form a film, removing the solvent by flushing with water, followed by drying and removing the obtained membrane material from the solid surface.

The disadvantage of the known method is caused by the following. The resulting forming solution is characterized by high viscosity. Significant viscosity of the solution at low electric conductivity in combination with the method of forming a membrane material from it (forming a film by dispersing) provides obtaining a non-homogeneous structure, non-uniform over its thickness. As a result, the final material is characterized by high water resistance, but low vapor permeability, thereby excluding the possibility of its use in the production of sportswear. The claimed method’s closest analogue, as for the technical essence, is a method for producing a textile material, designed for the production of medical clothing, for example, medical costumes, gowns (RU2579263 for the invention “Antimicrobial textile material with multicomponent nanomembranes and method for its production”, publ. 10.04.2016). The method includes preparing a forming solution by dissolving the polymer (polyvinylidenefluoride) in a solvent (acetic/formic acid) and electroforming fibres from the resulting solution in an electrostatic field.

The disadvantage of the known technical solution, selected as a prototype for the claimed method, forming solution and material, is obtaining a textile material, characterized by low vapor permeability and water resistance, as well as significant air permeability. This is due to the fact that the resulting forming solution is characterized by high viscosity and low electric conductivity. As a result, drawing-out nanofibres is complicated, fibres are formed different in thickness and, as a result, when laying nanofibres in a layer, the spatial structure of the obtained material becomes uneven, non-uniform in thickness and surface density. As a result, vapor and air passing through such a structure is hampered, and the possibility for unwanted moisture penetration increases.

SUMMARY OF THE INVENTION

The technical task consists in producing a textile membrane material, characterized by high vapor permeability and water resistance, at low air permeability.

The technical result consists in ensuring the uniform size, shape and spatial arrangement of nanofibres, forming the membrane layer.

The technical result is achieved by the fact, that according to the first embodiment of the method for producing a textile membrane material, including preparing a forming solution by dissolving the polymer in a solvent, electroforming nanofibres from the forming solution with simultaneous deposition on a base and removing the obtained membrane material from the said base, according to the invention, fluoroplast-2 is used as a polymer, a mixture of N,N- dimethylacetamide and ethylacetate or propylacetate in a ratio of 1 :1 is used as a solvent, the forming solution is obtained with a specific electric conductivity ae 13-17.6 ps/cm and zero dynamic viscosity h 0.298-0.341 Pa s, and fibres electroforming is carried out at difference in voltages on the electrodes of 75-120 kV and relative humidity of 10-45% in the electroforming chamber, wherein the base, on which nanofibres obtained are deposited, is moved at a speed of 0.125-1.0 m/min, then the obtained membrane material is fixed on a textile substrate. According to the method embodiments, a synthetic rubber and/or polyurethane is added in the forming solution; the obtained membrane material, consisting of polymeric nanofibres, is secured to the textile substrate by means of a thermoplastic adhesive when pressing on thermostatically controlled cylinder shafts. The technical result is also achieved by using a fluoroplast-2 as a polymer in a forming solution, to implement the method for producing a textile membrane material, comprising a polymer and a solvent, according to the invention, fluoroplast-2 is used as a polymer, and a mixture of N,N-dimethylacetamide and ethylacetate or propylacetate in a ratio of 1 : 1 is used as a solvent, with the following ratio of components, in wt.%:

fluoroplast -2 10-16

N,N-dimethylacetamide 42-45

ethylacetate or propylacetate 42-45,

wherein, the forming solution specific electric conductivity ae is 13-17.6 ps/cm, and zero dynamic viscosity h is 0.298-0.341 Pa s.

In an embodiment of the invention, the forming solution, to implement the method, contains a synthetic rubber and/or polyurethane, with the following ratio of components, in wt.%:

fluoroplast -2 10-14

synthetic rubber and/or polyurethane 0.1-2

N,N-dimethylacetamide 42-44.95

ethylacetate or propylacetate 42-44.95.

The textile membrane material, obtained according to the first embodiment of the method, containing the membrane material layer, consisting of polymeric nanofibres, according to the invention, comprises at least one textile substrate, secured to the membrane material layer, nanofibres of which are made of fluoroplast-2, the membrane material layer surface density is 10.0- 22.0 g/m ² , water resistance is greater than 5500 mm w.g., air permeability is at most 1.2 cftn, and vapor permeability is greater than 8000 g/m ² /24h.

The technical result is achieved by the fact that according to the second embodiment of the method for producing a textile membrane material, including preparing a forming solution by dissolving a polymer in a solvent, electroforming nanofibres from the forming solution with simultaneous deposition on a base and removing the obtained membrane material from the said base, according to the invention, a mixture of synthetic rubber and fluoroplast-2 is used as a polymer, a mixture of N,N- dimethylacetamide and ethylacetate or propylacetate in a ratio of 1 :1 is used as a solvent, a forming solution is obtained with a specific electric conductivity ae 7.0-9.5 ps/cm and zero dynamic viscosity h 0.32-0.34 Pa s, and fibres electroforming is carried out at difference in voltages on the electrodes of 60- 120 kV and relative humidity of 30-45% in the electroforming chamber, wherein the base, on which the obtained fibres are deposited, is moved at a speed of 0.125-0.5 m/min, then the obtained membrane material is fixed on a textile substrate. According to the method embodiments, the obtained membrane material, consisting of polymeric nanofibres, is secured to the textile substrate by means of a thermoplastic adhesive when pressing on thermostatically controlled cylinder shafts. The technical result is also achieved by using a mixture of synthetic rubber and fluoroplast-2 as a polymer in a forming solution, to implement the method, comprising a polymer and a solvent, according to the invention, a mixture of synthetic rubber and fluoroplast-2 is used as a polymer, and a mixture of N,N-dimethylacetamide and ethylacetate or propylacetate in a ratio of 1 : 1 is used as a solvent, with the following ratio of components, in wt.%:

synthetic rubber 12-15

fluoroplast-2 0.8-3.1

N,N-dimethylacetamide 40.95-43.6

ethylacetate or propylacetate 40.95-43.6,

wherein, the forming solution specific electric conductivity as is 7.0-9.5 ps/cm, and zero dynamic viscosity is h 0.32-0.34 Pa s.

The textile membrane material, obtained according to the second embodiment of the method, containing a membrane material layer, consisting of polymeric nanofibres, according to the invention, comprises at least one textile substrate, secured to the membrane material layer, nanofibres of which are made of a mixture of synthetic rubber and fluoroplast-2, the membrane material layer surface density is 10.0-22.0 g/m ² , water resistance is greater than 5500 mm w.g., air permeability is at most 1.2 cfm, and vapor permeability is greater than 8000 g/m ² /24h.

Justification of the optimal parameters for the method of producing a textile membrane material and a forming solution composition for its implementation was carried out as follows. For this purpose, forming solutions were prepared based on three different polymers: polyvinylidenefluoride (PVDF), synthetic rubber, and fluoroplastic-2. The prior art discloses, that polyvinylidenefluoride is a homopolymer, which macromolecule is built of monomer units -(CH ₂ - CF ₂ )-; fluoroplast-2 is a copolymer, which macromolecule is built of monomer units -(CH2-CF2) - and -(CF2-CF2)- ; fluorinated synthetic rubber is a polymer built of units -(CF2-CH2)- (CFCF3- CF2)-. The following were used as solvents for each polymer: N,N-dimethylacetamide (DMAA) and ethylacetate; N,N-dimethylacetamide (DMAA) and propylacetate; N,N-dimethylformamide (DMFA); propylacetate and N,N-dimethylacetamide. Some solutions included additives: synthetic rubber, polyurethane or fluoroplast-2. The polymers dissolving was carried out using a stirring mechanism at a speed of 750 min ¹ , gradually increasing the temperature to 50-55°C. Then followed cooling the solutions to a room temperature. The ratio of the solutions components for each sample and their physico-chemical characteristics are given in table 1.

Each sample of the forming solution was subjected to non-capillary electroforming, wherein a steel string was used as the working electrode. Deposition of formed nanofibres was implemented on the base, a paper web 0.08-0.15 mm thick, with a surface density of 85 g/m ² , placed under the depositing electrode. The circulation period of the measure feeder (carriage) was 1.2 s ¹ . Electroforming modes, varying during the experiment, and the textile membrane material samples characteristics are given in table 2. According to table 2, voltage parameters on the electrodes are specified for each of them separately, by the sign and difference in voltages on the electrodes corresponds to the difference in modulus (for example, -40/+80 kV is equal to 120 kV, -15 /+60 is equal to 75 kV).

According to table 1, the forming solution qualitative and quantitative composition significantly affects its physico-chemical properties, dynamic viscosity and electric conductivity. Thus, the highest viscosity indices are observed in solutions based on PVDF (samples Nos. 14, 15, 17, 19, 21-24), and the lowest ones - in solutions based on fluoroplast-2 (Nos. 2, 3, 6, 7, 9, 10). From the table 2 it can be seen, that varying the conditions of electroforming (relative humidity in the chamber, difference in voltages on the electrodes, the base movement speed) from solutions with different rheological and electrically conductive properties allows obtaining textile materials with wide range of functional properties.

However, the required set of performance characteristics (high vapor permeability and water resistance at low air permeability) can be obtained only under a predetermined combination of physico-chemical characteristics of the solution and electroforming conditions.

Thus, in spite of satisfactory dynamic viscosity and specific electic conductivity of the solution sample No. 12 under varying electroforming conditions (relative humidity and the base movement speed), the membrane material samples with different properties were obtained, but they did not meet the requirements for the production of sportswear and textiles, i.e. high air permeability at low water resistance and vapor permeability.

The textile membrane materials, obtained on the basis of the forming solution samples Nos. 22, 23, 24 with unsatisfactory dynamic viscosity and specific electric conductivity, under various electroforming conditions, have air permeability values, lying within an acceptable performance range of 1.0 - 1.2 cfm. At the same time, the values of water resistance and vapor permeability of such materials are extremely unsatisfactory (1500 - 3400 mm w.g. and 5500-6700 g/m ² /24 h). The solution sample No. 26, having unsatisfactory dynamic viscosity and specific electric conductivity, under various electroforming conditions allowed to obtain the membrane material with low vapor permeability and insufficient air permeability.

In contrast, the forming solution samples Nos. 1, 8, 25 under various conditions of fibres electroforming made it possible to obtain the textile membrane materials, having optimal performance parameters - high vapor permeability and water resistance at low air permeability. Under varying the ratio of components in such solutions, the dynamic viscosity and specific electric conductivity parameters were changed significantly. Thus, varying the proportions of solvents in the dissolving system and reducing the weight content of fluoroplast-2 in the forming solution reduced the solution dynamic viscosity parameter (samples Nos. 2, 3, 9, 10), resulting in the formation of membrane materials, having unsatisfactory set of performance characteristics. Increasing the weight content of fluoroplast-2 in the forming solution increased the dynamic viscosity parameter (samples Nos. 4, 13), and also ensured producing the textile membrane material under various electroforming conditions with unsatisfactory set of performance characteristics. The technical result achievement during the implementation of the claimed group of inventions is provided due to the following.

Using fluoroplast-2 or a mixture of synthetic rubber and fluoroplast-2 as a polymer in combination with dissolving in a mixture of N,N-dimethylacetamide and ethylacetate or propylacetate in specified ratio ensures obtaining a forming solution with an optimal range of performance parameters, i.e. zero dynamic viscosity h and specific electric conductivity ae. This provides the possibility to form fibres in a high voltage field within a wide range of parameters of relative humidity and speeds of the base movement for deposition, which, in turn, allows drawing- out nanofibres with a narrow distribution along the diameter (at most 450 Nm) and a uniform shape and performing their deposition on the base with optimal density. Thus, producing a membrane material, consisting of polymeric nanofibres (fibrous layer) with a homogeneous morphology, characterized by high vapor permeability and water resistance at low air permeability is ensured.

Adding synthetic rubber and/or polyurethane to the forming solution based on fluoroplast-2 at a concentration of 0-2 wt.% further facilitates the possibility to vary the solution performance parameters and, consequently, the possibility to form nanofibres of a specified diameter at a simultaneous laying thereof with a specified surface density.

Applying the obtained membrane material, consisting of polymeric nanofibres, on a textile substrate with subsequent fastening with a thermoplastic adhesive when pressing on thermostatically controlled cylinder shafts (lamination process) further contributes to increasing the water permeability and reducing the air permeability of the obtained textile membrane material. Polyurethane adhesive, applied in the form of a small-dotted pattern on one of the surfaces to be laminated, can be used as a thermoplastic adhesive. The key factors during the lamination procedure are the type and density of adhesive application, the speed and temperature mode of pressing. The obtained textile membrane material (laminate) may comprise two or more layers:

- membrane material itself, consisting of polymeric nanofibres (fibrous layer), which determines the functional properties;

- upper side (face) layer - drapery fabric, which determines the appearance and mechanical properties;

- back side layer (its presence in some cases is optional) - knitted net, designed for mechanical protection of the membrane during the garment wearing.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is accompanied by the drawings, in which fig. 1 shows a micrograph of the membrane material layer (based on fluoroplast-2), obtained by scanning electron microscopy method with a 150-fold magnification; fig. 2 shows a micrograph of the membrane material layer (based on fluoroplast-2) with a 5000-fold magnification; fig. 3 shows a micrograph of the membrane material layer (based on fluoroplast-2, with addition of fluorinated synthetic rubber) with a 150-fold magnification; fig. 4 shows a micrograph of the membrane material layer (based on fluoroplast-2, with addition of fluorinated synthetic rubber) with a 5000-fold magnification; fig. 5 shows a micrograph of the membrane material layer (based on fluoroplast-2, with addition of polyurethane) with 150-fold magnification; fig. 6 shows a micrograph of the membrane material layer (based on fluoroplast-2, with addition of polyurethane) with a 5000-fold magnification.

DETAILED DESCRIPTION OF THE INVENTION

The invention concept is illustrated by the following examples, in which preparing the forming solution to obtain the membrane material layer, consisting of polymeric nanofibres, was implemented as described above.

Example 1.1

Forming solution: fluoroplast-2 - 10 g, N,N-dimethylacetamide - 45 g, ethylacetate - 45 g.

Physico-chemical characteristics of the forming solution: dynamic viscosity h = 0.305 Pa s, specific electric conductivity ae = 16.8 ps/cm.

Electroforming conditions: voltage on the electrodes is -15/+60 kV (difference in voltages makes 75 kV), relative humidity in the chamber is 25%, the base movement speed is 0.125 m/min.

As a result, a membrane material was obtained with the following parameters: thickness - 0.08 mm, surface density - 22 g/m ² , vapor permeability - 8700 g/m ² /24h, water resistance - 6000 mm w.g., air permeability - 1.2 cftn. In this case, according to scanning electron microscopy data (fig. 1 , 2), the membrane material surface morphology is characterized by the absence of bead-type defects, large drops, nubby formations and density variation.

Example 1.2

Forming solution: fluoroplast-2 - 10 g, N,N-dimethylacetamide - 45 g, ethylacetate - 45 g.

Physico-chemical characteristics of the forming solution: dynamic viscosity h = 0.305 Pa s, specific electric conductivity ae = 16.8 ps/cm.

Electroforming conditions: voltage on the electrodes is -40/+50 kV (difference in voltages makes 90 kV), relative humidity in the chamber is 25%, the base movement speed is 0.75 m/min.

As a result, a membrane material was obtained with the following parameters: thickness - 0.06 mm, surface density - 10 g/m ² , vapor permeability - 8900 g/m ² /24h, water resistance - 8000 mm w.g., air permeability - 1.2 cfm.

Example 1.3

Forming solution: fluoroplast-2 - 10 g, N,N-dimethylacetamide - 45 g, ethylacetate - 45 g. Physico-chemical characteristics of the forming solution: dynamic viscosity h = 0.305 Pa s, specific electric conductivity ae = 16.8 ps/cm.

Electroforming conditions: voltage on the electrodes is -40/+50 kV (difference in voltages makes 90 kV), relative humidity in the chamber is 40%, the base movement speed is 0.75 m/min.

As a result, a membrane material was obtained with the following parameters: thickness - 0.07 mm, surface density - 14 g/m ² , vapor permeability - 9200 g/m ² /24 h, water resistance— 6000 mm w.g., air permeability - 1.2 cfm.

Example 2.1

Forming solution: fluoroplast-2 - 13 g, synthetic rubber - 1.0 g, N,N-dimethylacetamide - 43 g, ethylacetate - 43 g.

Physico-chemical characteristics of the forming solution: dynamic viscosity h = 0.320 Pa s, specific electric conductivity ae = 15.2 ps/cm.

Electroforming conditions: voltage on the electrodes is -15/+60 kV (difference in voltages makes 75 kV), relative humidity in the chamber is 25%, the base movement speed is 0.125 m/min.

As a result, a membrane material was obtained with the following parameters: thickness - 0.08 mm, surface density - 19 g/m ² , vapor permeability - 9000 g/m ² /24 h, water resistance - 10000 mm w.g., air permeability - 1.00 cfm. In this case, according to scanning electron microscopy data (fig. 3), the membrane material surface morphology is characterized by the absence of bead-type defects, large drops, nubby formations and density variation.

Example 2.2

Forming solution: fluoroplast-2 - 13 g, synthetic rubber - 1.0 g, N,N-dimethylacetamide - 43 g, ethylacetate - 43 g.

Physico-chemical characteristics of the forming solution: dynamic viscosity h = 0.320 Pa s, specific electric conductivity ae = 15.2 ps/cm.

Electroforming conditions: voltage on the electrodes is -15/+60 kV (difference in voltages makes 75 kV), relative humidity in the chamber is 25%, the base movement speed is 0.5 m/min.

As a result, a membrane material was obtained with the following parameters: thickness - 0.03 mm, surface density - 15 g/m ² , vapor permeability - 8700 g/m ² /24h, water resistance - 8500 mm w.g., air permeability - 0.9 cfm.

Example 2.3

Forming solution: fluoroplast-2 - 13 g, synthetic rubber - 1.0 g, N,N-dimethylacetamide - 43 g, ethylacetate - 43 g. Physico-chemical characteristics of the forming solution: dynamic viscosity h = 0.320 Pa s, specific electric conductivity as = 15.2 ps/cm.

Electroforming conditions: voltage on the electrodes is -15/+60 kV (difference in voltages makes 75 kV), relative humidity in the chamber is 35%, the base movement speed is 0.4 m/min.

As a result, a membrane material was obtained with the following parameters: thickness - 0.05 mm, surface density - 16 g/m ² , vapor permeability - 8900 g/m ² /24h, water resistance - 6200 mm w.g., air permeability - 1.2 cfm.

Example 3.1

Forming solution: fluoroplast-2 - 10 g, N,N-dimethylacetamide - 45 g, propylacetate - 45 g.

Physico-chemical characteristics of the forming solution: dynamic viscosity h = 0.300 Pa s, specific electric conductivity as = 17.0 ps/cm.

Electroforming conditions: voltage on the electrodes is -15/+60 kV (difference in voltages makes 75 kV), relative humidity in the chamber is 25%, the base movement speed is 0.125 m/min.

As a result, a membrane material was obtained with the following parameters: thickness— 0.08 mm, surface density - 14 g/m ² , vapor permeability - 8800 g/m ² /24h, water resistance - 5700 mm w.g., air permeability - 1.1 cfm.

Example 3.2

Forming solution: fluoroplast-2 - 10 g, N,N-dimethylacetamide - 45 g, propylacetate - 45 g.

Physico-chemical characteristics of the forming solution: dynamic viscosity h = 0.300 Pa s, specific electric conductivity ae = 17.0 ps/cm.

Electroforming conditions: voltage on the electrodes is -15/+60 kV (difference in voltages makes 75 kV), relative humidity in the chamber is 25%, the base movement speed is 0.75 m/min.

As a result, a membrane material was obtained with the following parameters: thickness - 0.06 mm, surface density - 13 g/m ² , vapor permeability - 8700 g/m ² /24h, water resistance - 5500 mm w.g., air permeability - 1.1 cfm.

Example 4.1

Forming solution: fluoroplast-2 - 12 g, polyurethane - 0.2 g, N,N-dimethylacetamide - 43.9 g, propylacetate - 43.9 g.

Physico-chemical characteristics of the forming solution: dynamic viscosity h = 0.312 Pa s, specific electric conductivity as = 15.8 ps/cm.

Electroforming conditions: voltage on the electrodes is -15/+60 kV (difference in voltages makes 75 kV), relative humidity in the chamber is 30%, the base movement speed is 0.5 m/min. As a result, a membrane material was obtained with the following parameters: thickness - 0.075 mm, surface density - 15 g/m ² , vapor permeability - 9000 g/m ² /24 h, water resistance - 7000 mm w.g., air permeability - 1.2 cfm. In this case, according to scanning electron microscopy data (fig. 5, 6), the membrane material surface morphology is characterized by the absence of bead-type defects, large drops, nubby formations and density variation.

Example 4.2

Forming solution: fluoroplast-2 - 12 g, polyurethane - 0.2 g, N,N-dimethylacetamide - 43.9 g, propylacetate - 43.9 g.

Physico-chemical characteristics of the forming solution: dynamic viscosity h = 0.312 Pa s, specific electric conductivity ae = 15.8 ps/cm.

Electroforming conditions: voltage on the electrodes is -40/+50 kV (difference in voltages makes 90 kV), relative humidity in the chamber is 30%, the base movement speed is 0.5 m/min.

As a result, a membrane material was obtained with the following parameters: thickness— 0.070 mm, surface density - 12 g/m ² , vapor permeability - 9320 g/m ² /24h, water resistance - 7200 mm w.g., air permeability - 1.15 cfm.

Example 4.3

Forming solution: fluoroplast-2 - 12 g, polyurethane - 0.2 g, N,N-dimethylacetamide - 43.9 g, propylacetate - 43.9 g.

Physico-chemical characteristics of the forming solution: dynamic viscosity h = 0.312 Pa s, specific electric conductivity ae = 15.8 ps/cm.

Electroforming conditions: voltage on the electrodes is -40/+80 kV (difference in voltages makes 120 kV), relative humidity in the chamber is 30%, the base movement speed is 0.5 m/min.

As a result, a membrane material was obtained with the following parameters: thickness— 0.070 mm, surface density - 13 g/m ² , vapor permeability - 9900 g/m ² /24h, water resistance - 7500 mm w.g., air permeability - 1.1 cfm.

Example 5.1

Forming solution: fluoroplast-2 - 13 g, N,N-dimethylacetamide - 43.5 g, propylacetate -

43.5 g.

Physico-chemical characteristics of the forming solution: dynamic viscosity h = 0.310 Pa s, specific electric conductivity ae = 16.7 ps/cm.

Electroforming conditions: voltage on the electrodes is -15/+60 kV (difference in voltages makes 75 kV), relative humidity in the chamber is 25%, the base movement speed is 0.125 m/min. As a result, a membrane material, consisting of polymeric nanofibres, was obtained with the following parameters: thickness - 0.075 mm, surface density - 16 g/m ² , vapor permeability - 9000 g/m ² /24h, water resistance - 8500 mm w.g., air permeability - 1.0 cfm.

The membrane material, consisting of polymeric nanofibres, obtained as a result of electroforming, was subjected to lamination: secured to 28 g/m ² polyamide knitted net, 0.176 mm thick (back side layer) and to 137 g/m ² polyester woven fabric, 0.235 mm thick (face layer).

Parameters of the obtained textile membrane material: vapor permeability - 9000 g/m ² /24h, water resistance - 8500 mm w.g., air permeability - 1.00 cfm.

Example 5.2

Forming solution: fluoroplast-2 - 11.1 g, synthetic rubber - 2 g, N,N-dimethylacetamide - 43.5 g, propylacetate - 43.5 g.

Physico-chemical characteristics of the forming solution: dynamic viscosity h = 0.305 Pa s, specific electric conductivity ae = 17.9 ps/cm.

Electroforming conditions: voltage on the electrodes is -40/+80 kV (difference in voltages makes 120 kV), relative humidity in the chamber is 25%, the base movement speed is 0.455 m/min.

As a result, a membrane material, consisting of polymeric nanofibres, was obtained with the following parameters: thickness - 0.074 mm, surface density - 12 g/m ² , vapor permeability - 8700 g/m ² /24h, water resistance - 5500 mm w.g., air permeability - 1.2 cfm.

The membrane material, consisting of polymeric nanofibres, obtained as a result of electroforming, was subjected to lamination: secured to 28 g/m ² polyamide knitted net, 0.176 mm thick (back side layer) and to polyester woven fabric, with surface density of 53 g/m ² , 0.1 mm thick (face layer).

Parameters of the obtained textile membrane material: vapor permeability - 8700 g/m ² /24h, water resistance - 5500 mm w.g., air permeability - 1.2 cfm.

Example 5.3

Forming solution: fluoroplast-2 - 11.7 g, synthetic rubber - 1.3 g, N,N-dimethylacetamide - 43.5 g, propylacetate - 43.5 g.

Physico-chemical characteristics of the forming solution: dynamic viscosity h = 0.315 Pa s, specific electric conductivity ae = 17.2 ps/cm.

Electroforming conditions: voltage on the electrodes is -40/+80 kV (difference in voltages makes 120 kV), relative humidity in the chamber is 25%, the base movement speed is 0.25 m/min. As a result, a membrane material, consisting of polymeric nanofibres, was obtained with the following parameters: thickness - 0.070 mm, surface density - 10.5 g/m ² , vapor permeability - 8900 g/m ² /24h, water resistance - 7000 mm w.g., air permeability - 1.1 cfm.

The membrane material, consisting of polymeric nanofibres, obtained as a result of electroforming, was subjected to lamination: secured to 28 g/m ² polyamide knitted net, 0.176 mm thick (back side layer) and to polyester woven fabric, with surface density of 114 g/m ² , 0.2 mm thick.

Parameters of the obtained textile membrane material: vapor permeability - 8900 g/m ² /24h, water resistance - 7000 mm w.g., air permeability - 1.1 cfm.

Example 6.1

Forming solution: synthetic rubber - 14.8 g, fluoroplast-2 - 1.2 g, N,N-dimethylacetamide - 42 g, propylacetate - 42 g.

Physico-chemical characteristics of the forming solution: dynamic viscosity h = 0.32 Pa s, specific electric conductivity $ = 9.11 ps/cm.

Electroforming conditions: voltage on the electrodes is -32/+32 kV (difference in voltages makes 64 kV), relative humidity in the chamber is 45%, the base movement speed is 0.50 m/min.

As a result, a membrane material, consisting of polymeric nanofibres, was obtained with the following parameters: surface density - 18 g/m ² , thickness - 0.07 mm, vapor permeability - 9300 g/m ² /24h, water resistance - 9400 mm w.g., air permeability - 0.1 cfm.

Example 6.2

Forming solution: synthetic rubber - 14.8 g, fluoroplast-2 - 1.2 g, N,N-dimethylacetamide - 42 g, propylacetate - 42 g.

Physico-chemical characteristics of the forming solution: dynamic viscosity h = 0.325 Pa s, specific electric conductivity ae = 9.11 ps/cm.

Electroforming conditions: voltage on the electrodes is -40/+40 kV (difference in voltages makes 80 kV), relative humidity in the chamber is 30%, the base movement speed is 0.30 m/min.

As a result, a membrane material, consisting of polymeric nanofibres, was obtained with the following parameters: surface density - 19 g/m ² , thickness - 0.04 mm, vapor permeability - 9500 g/m ² /24h, water resistance - 10000 mm w.g., air permeability - 0.037 cfm.

Example 7.1

Forming solution: synthetic rubber - 15 g, fluoroplast-2 - 1 g, N,N-dimethylacetamide - 42 g, propylacetate - 42 g. Physico-chemical characteristics of the forming solution: dynamic viscosity h = 0.34 Pa s, specific electric conductivity as = 8.3 ps/cm.

Electroforming conditions: voltage on the electrodes is -32/+32 kV (difference in voltages makes 64 kV), relative humidity in the chamber is 45%, the base movement speed is 0.30 m/min.

As a result, a membrane material, consisting of polymeric nanofibres, was obtained with the following parameters: surface density - 20 g/m ² , thickness - 0.04 mm, vapor permeability - 9400 g/m ² /24h, water resistance - 9800 mm w.g., air permeability - 0.05 cfm.

Example 8.1

Forming solution: synthetic rubber - 14.7 g, fluoroplast-2 - 0.8 g, N,N-dimethylacetamide -

42.3 g, propylacetate - 42.3 g.

Physico-chemical characteristics of the forming solution: dynamic viscosity h = 0.32 Pa s, specific electric conductivity ae = 9.05 ps/cm.

Electroforming conditions: voltage on the electrodes is 321+32 kV (difference in voltages makes 64 kV), relative humidity in the chamber is 45%, the base movement speed is 0.125 m/min.

As a result, a membrane material, consisting of polymeric nanofibres, was obtained with the following parameters: surface density - 22 g/m ² , thickness - 0.07 mm, vapor permeability - 9300 g/m ² /24h, water resistance - 10500 mm w.g., air permeability - 0.05 cfm.

Example 9

Forming solution: synthetic rubber - 13.9 g, fluoroplast-2 - 1.6 g, N,N-dimethylacetamide -

42.3 g, propylacetate - 42.3 g.

Physico-chemical characteristics of the forming solution: dynamic viscosity h = 0.327 Pa s, specific electric conductivity ae = 8.69 ps/cm.

Electroforming conditions: voltage on the electrodes is 321+32 kV (difference in voltages makes 64 kV), relative humidity in the chamber is 35%, the base movement speed is 0.50 m/min.

As a result, a membrane material, consisting of polymeric nanofibres, was obtained with the following parameters: surface density - 16 g/m ² , thickness - 0.06 mm, vapor permeability - 9000 g/m ² /24h, water resistance - 8500 mm w.g., air permeability - 0.25 cfm.

Example 10

Forming solution: synthetic rubber - 13.1 g, fluoroplast-2 - 2.3 g, N,N-dimethylacetamide -

42.3 g, propylacetate - 42.3 g.

Physico-chemical characteristics of the forming solution: dynamic viscosity h = 0.325 Pa s, specific electric conductivity ae = 8.8 ps/cm. Electroforming conditions: voltage on the electrodes is -32/+32 kV (difference in voltages makes 64 kV), relative humidity in the chamber is 40%, the base movement speed is 0.45 m/min.

As a result, a membrane material, consisting of polymeric nanofibres, was obtained with the following parameters: surface density - 16.5 g/m ² , thickness - 0.07 mm, vapor permeability - 8900 g/m ² /24h, water resistance - 8200 mm w.g., air permeability - 0.3 cftn.

Example 11

Forming solution: synthetic rubber - 12.4 g, fluoroplast-2 - 3.1 g, N,N-dimethylacetamide - 42.3 g, propylacetate - 42.3 g.

Physico-chemical characteristics of the forming solution: dynamic viscosity h = 0.322 Pa s, specific electric conductivity ae = 9.4 ms/cm.

Electroforming conditions: voltage on the electrodes is -32/+32 kV (difference in voltages makes 64 kV), relative humidity in the chamber is 45%, the base movement speed is 0.35 m/min.

As a result, a membrane material was obtained with the following parameters: surface density - 16.0 g/m ² , thickness - 0.08 mm, vapor permeability - 8700 g/m ² /24h, water resistance - 9200 mm w.g., air permeability - 0.29 cfm.

The membrane material, consisting of polymeric nanofibres, obtained as a result of electroforming, was subjected to lamination: secured to 28 g/m ² polyamide knitted net, 0.176 mm thick (back side layer) and to polyester woven fabric, with surface density of 53 g/m ² , 0.1 mm thick.

Parameters of the obtained textile membrane material: vapor permeability - 8700 g/m ² /24h, water resistance - 9200 mm w.g., air permeability - 0.29 cfm.

The given examples show, that varying the ratio of the components of the forming solution in combination with the electroforming conditions and further processing allows to obtain a textile membrane with different functional properties.

Thus, the claimed embodiments of the method for producing a textile membrane material and a forming solution, used for its implementation, ensure producing a membrane material, consisting of polymeric nanofibres of homogeneous morphology, which, in turn, results to high vapor permeability and water resistance at low air permeability of the produced textile membrane material.