RU2248838C1 - Method of production of a filtering material, the filtering material, a means of protection of respiratory organs - Google Patents

Abstract

FIELD: fine-fiber filtering materials.

SUBSTANCE: the invention is pertinent to fine-fiber filtering materials used for individual means of protection of respiratory organs. The invention offers a protection material, a means of protection containing the offered material and a method of production of the fibrous material providing for electrostatic forming of the fibrous material from a solution of styrene copolymer with acrylonitrile in an organic solvent at the presence of electrostatic additives of bromide or iodide salts of tetraethyl- or tetrabutyl-ammonium. At that a solution containing an additive of a high-molecular methylmethacrylate in amount of 0.001-0.01 mass % in the capacity of dissolvent is used a mixture of ethyl acetate with butyl acetate at their mass ratio in the solution from 1/9 up to 9/1 accordingly. The invention allows to produce a material with improved mechanical characteristics and to provide stability of the production process.

EFFECT: the invention ensures production of the material with improved mechanical characteristics and stability of the production process.

5 cl, 2 tbl, 1 ex

Description

The invention relates to the field of production of fibrous filter materials used to protect the environment, as well as respiratory organs from toxic aerosols.

Known filter material for respiratory protection, containing the outer and inner protective layers and the working layer of fibers of perchlorovinyl and a styrene copolymer with methyl methacrylate and acrylonitrile, while the fibers contain 1-9 wt.% Perchlorovinyl and 91-99 wt.% Styrene copolymer with methyl methacrylate and acrylonitrile, or 91-99 wt.% perchlorovinyl and 1-9 wt.% copolymer of styrene with methyl methacrylate and acrylonitrile.

A method for producing a known material involves electrostatically molding a nonwoven material from a 5-25% dichloroethane solution of a mixture of perchlorovinyl and a copolymer of styrene with methyl methacrylate and acrylonitrile in the presence of 0.01-0.2% tetraethylammonium or tetrabutylammonium halides or iron halides by weight of polymers, perchlorovinyl is taken in an amount of 1-9 wt.% or 91-99 wt.% from the mixture of polymers present in the solution (RU 2170607).

Also known is filter material for respirators containing the outer and inner protective layers and a working layer of polymeric fibrous material, in which the working layer is made of a mixture of fibrous polymers of perchlorovinyl and a copolymer of styrene with methyl methacrylate and acrylonitrile in a mass ratio of 10 / 1-1 / 1.

There is also a method of producing a filter material of the above type, comprising electrostatically forming a fibrous non-woven material from a solution of perchlorovinyl and a copolymer of styrene with methyl methacrylate and acrylonitrile in a mass ratio of 10 / 1-1 / 1 in dichloroethane in the presence of salts selected from the series: iodide or bromide tetraethylammonium or iodide or bromide tetrabutylammonium, or ferric chloride, taken in an amount of 0.01-0.2 wt.% (RU 2135263).

Closest to the proposed technical solution is a method of obtaining a filter material from a solution of a copolymer of styrene with acrylonitrile, contained in an amount of 10-20 wt.% In a solution of dichloroethane, which contains acetone, or methyl ethyl ketone, or ethyl acetate, or butyl acetate in the amount of 5-30 wt. %, as well as a filter material comprising a fiber diameter of 1-10 microns, which are formed of a copolymer of styrene with acrylonitrile and having a weight of 20-80 g / m ² and air resistance 3-60 Pa at Air flow rate ha 1 cm / s, and in addition, the breathing apparatus, comprising a working layer of fibers 1-10 microns in diameter, a protective layer of gauze and filtrderzhatel, wherein the fibers of the working layer made of a copolymer of styrene with acrylonitrile (RU 2182511).

A disadvantage of the known technical solutions is the low adaptability of the process of forming the fibrous material, as well as the insufficient strength of the material obtained.

The objective of the present invention is to develop a filter material from fibers of a styrene-acrylonitrile copolymer having increased mechanical strength and stabilization of the process for producing this material, as well as a respiratory protection with a working layer of fiber with improved characteristics.

The problem is solved by the described method, including the electrostatic molding of a fibrous material from a solution of a styrene-acrylonitrile copolymer in an organic solvent — a mixture of ethyl acetate and butyl acetate in a mass ratio of 1/9 to 9/1, respectively, in the presence of high molecular weight methyl methacrylate in an amount of 0.001-0.01 wt. % and in the presence of electrolytic additives of bromide or iodide salts of tetraethyl or tetrabutylammonium.

Preferably, the molding of the material is carried out from a solution containing in wt.%:

styrene-acrypnitrile copolymer 16-26

high molecular weight methyl methacrylate 0.001-0.01

electrolytic additives 0.001-0.01

solvent rest

The problem is also solved by the filtering material containing fibers from a copolymer of styrene with acrylonitripe with a diameter of 1-10 microns, obtained by the method described above.

In addition, the task is solved by means of respiratory protection, containing a working layer of styrene-acrylonitrile copolymer fibers with a diameter of 1-10 μm, a frame layer of gauze or non-woven material, a rubber cord, a seal, a headband.

Example 1

Prepare a 17% spinning solution of a styrene-acrylonitrile copolymer in a mixture of butyl acetate and ethyl acetate in a mass ratio with a dynamic viscosity of 4.8 pz; the conductivity of the solution is adjusted to 4 · 10 ^-6 Ohm ^-1 cm ^-1 , introducing an electrolytic additive of 0.0035 wt.% TEAI. Then fibrous material is formed in an electrostatic field with a potential difference of 35 kV and a solution volumetric flow rate of 5 · 10 ^-3 cm ³ / s per spinning element.

A fibrous layer of ultrathin fibers with an average size of 2 microns in diameter is obtained on a grounded metal electrode. The production process is more stable. Drying of the liquid filament emanating from the nozzle is not observed, and as a result, the electroforming process is stable.

Other examples of obtaining material from different compositions of the solution and the test results are shown in the table.

From the data in the table it is seen that the filter materials obtained in accordance with the invention have filter characteristics at the prototype level and higher mechanical strength (see elongation).

From the obtained materials, personal protective equipment for respiratory organs of the “Petal” type is made, containing a working layer of the claimed material deposited on a substrate of hygienic material, for example, gauze, or inserted into a filter holder of any known type, for example, F-62. The filter holder can be made, for example, in the form of a half mask, bandages, etc.

Claims (5)

1. A method of obtaining a filter material, comprising electrostatically molding a fibrous material from a solution of a styrene-acrylonitrile copolymer in an organic solvent in the presence of electrolytic additives of bromide or iodide salts of tetraethyl or tetrabutylammonium, characterized in that the molding is carried out from a solution additionally containing high molecular weight methyl methacrylate in an amount of 0.001 -0.01 wt.%, While a mixture of ethyl acetate and butyl acetate is taken as a solvent at a weight ratio of solution from 1/9 to 9/1, respectively. 2. The method according to claim 1, characterized in that the organic solvent additionally contains acetone in an amount of 1-5 wt.%. 3. The method according to claim 1, characterized in that the molding of the material is carried out from a solution containing in wt.%: The styrene copolymer with acrylonitrile 16-26 High molecular weight methyl methacrylate 0.001-0.01 Electrolytic additives 0.001-0.01 Solvent Else 4. Filter material containing fibers from a copolymer of styrene with acrylonitrile with a diameter of 1-10 μm, characterized in that it is obtained by the method described in claims 1-3. 5. Respiratory protection agent containing a working layer of styrene-acrylonitrile copolymer fibers with a diameter of 1-10 μm, a skeleton layer of gauze or non-woven material, a rubber cord, a shutter, a headband, characterized in that it contains a working layer of fibers obtained the method described in claims 1-3.