The method of obtaining the filtering material, the filtering material and means for respiratory protection
(57) Abstract:The invention relates to the field of fibrous filtering materials and products based on them. Method for obtaining a filtering material of a copolymer of styrene-acrylnitrile diameter fibers 1-10 μm from a spinning solution containing dichloroethane, electrolytic additives and solvents from the series: acetone, or methyl ethyl ketone, or ethyl acetate, or butyl acetate. The filter material has a surface density of 20-80 g/m2and aerodynamic resistance 3-60 PA at a flow rate of air of 1 cm/s Of the filter material is made respirator type "Petal". The invention allows to improve the operational characteristics of the obtained materials. 3 S. p. f-crystals, 2 tab. The invention relates to the field of fibrous filtering materials used to protect the environment, as well as respiratory organs from toxic aerosols.To obtain effective filter materials are widespread method of electrostatic spinning of fibers from polymer solutions. The range of possible materials obtained by this method, and various fields of application detailsTo enable the use of fibrous materials in different conditions and in different environments is an actual expansion of the range of fibre-forming polymers, the selection of optimal solvents and conditions of formation.For example, the known filter material and a method thereof, in which the molding is subjected to a solution containing 11-25% polysulfone and 0.1-5% polyvinylpyrrolidone in apretando solvent type, dimethylformamide, dimethylacetamide, dimethyl sulfoxide, N-methylpyrrolidone. (EN, 2086296, B 01 D 39/16, 1997).The obtained fibrous material effective for separation processes: dialysis, ultrafiltration, hemofiltration, division of blood.For purification of air and gases from the suspended solid particles and a known filter material consisting of a layer of polydisperse electrically charged ultrafine fibers of a copolymer of styrene with methyl methacrylate and acrylnitrile with a diameter of 1-2 μm and a diameter of 6-10 microns (EN, 2049525, B 01 D 39/16, 1995).However, the known material has a low mechanical strength.The closest to the invention is a filter material made from a mixture of polymers perchloride the Oia of this material, includes electropermanent fibers from a mixture of these polymers in solvent - dichloroethane in the presence of electrolyte additives in the form of iodide or bromide salts of tetraethylammonium or tetrabutylammonium chloride or iron in an amount of 0.01 to 0.2%, while the amount of solvent in the fibre-forming composition take from 5 to 15 wt.%, and the concentration of the polymer in dichloromethane ranging from 5 to 25%.The resulting material is placed on the substrate of the finished Marley and used in the construction of the respirator type "Petal"(EN, 2135263, B 01 D 39/16, 1999).However, the thus obtained filter material has a coefficient overshoot more than 1% at the most penetrating particle, which impairs the effectiveness of the respiratory protection, manufactured on its basis.The present invention is to develop a method of producing a filtering material with high efficiency detention the most penetrating particle that contributes to the manufacture of respirators with low breathing resistance while maintaining efficiency at a high level.The problem is solved by the described method of obtaining the filtering material is holding dichloroethane and electrolyte supplements from a number (wt.%): bromide or iodide, tetrabutylammonium or tetraethylammonium - of 0.01 - 0.1 (wt.%).Moreover, as the polymer take a copolymer of styrene-acrylnitrile in the amount of 10-20 wt.% and molding lead from the solution, optionally containing acetone, or methyl ethyl ketone, or ethyl acetate, or butyl acetate in the amount of 5-30 wt.%.The problem is solved also by the filter material, containing functional layer of polymeric fibers obtained by electrostatic molding, while it contains fibers of a copolymer of styrene-acrylnitrile diameter of 1-10 μm, the surface density of 20-80 g/m2and aerodynamic 3-60 PA at a flow rate of air of 1 cm/sec.The problem is solved also stated remedy for respiratory protection, containing a working layer of fibers of a copolymer of styrene-acrylnitrile obtained by electrostatic spinning and having a diameter of 1-10 mm, the surface density of 20-80 g/m2the drag 3-60 PA at a speed of 1 cm/s, and a protective layer and a filter holder.The following is an example of a filter material and characteristics of the filter material.Example
Prepare 17% spinning solution of a copolymer stir the Poises; bring the conductivity of the solution up to 410-6Ω-1cm-1by introducing an electrolytic additive - 0.03 wt.% TEA. Then spend the molded fibrous material in an electrostatic field with a potential difference of 35 kV and a volumetric flow solution 310-3cm3on one injector.On a grounded metal electrode receive the fibrous layer of ultra-thin fibers with an average fiber size of 2 microns.Thus obtained filter material is laboratory tested. Other examples for the material of the different composition of the solution and the test results are given in table. 1 and 2.From these tables it is seen that the filter materials obtained in accordance with the invention have the improved filtering characteristics.Of the submissions made personal respiratory protection type "Petal", containing a working layer of declared material deposited on a substrate of the finished gauze or insert the filter holder of any known type, such as f-62. The filter holder can be performed, for example, in the form of masks, headbands, etc. 1. The method of obtaining fillrowmethodname solvent, containing dichloroethane and electrolytic additives in the form of a bromide or iodide salts of tetraethylammonium or tetrabutylammonium, characterized in that the polymer contains a copolymer of styrene-acrylnitrile in the amount of 10-20 wt. %, the solution additionally contains acetone, or methyl ethyl ketone, or ethyl acetate, or butyl acetate in the amount of 5-30 wt. %.2. The filter material containing a working layer of polymer fibers with a diameter of 1-10 μm, the obtained electrostatic molding, characterized in that the fiber is made of a copolymer of styrene-acrylnitrile and having a surface density of 20-80 g/m2and aerodynamic resistance 3-60 PA at a flow rate of air of 1 cm/sec.3. Means of respiratory protection, containing a working layer of polymer fibers with a diameter of 1-10 μm, the protective layer of gauze and filter holder, characterized in that the functional layer is made of fibers of a copolymer of styrene-acrylnitrile, with surface density of 20-80 g/m2and aerodynamic 3-60 PA at the air flow rate of 1 cm/S.
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