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WO2021172753A1 - Nanofiltre ayant une efficacité de filtre améliorée et une durée de vie améliorée, et son procédé de fabrication - Google Patents

Nanofiltre ayant une efficacité de filtre améliorée et une durée de vie améliorée, et son procédé de fabrication Download PDF

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Publication number
WO2021172753A1
WO2021172753A1 PCT/KR2021/000520 KR2021000520W WO2021172753A1 WO 2021172753 A1 WO2021172753 A1 WO 2021172753A1 KR 2021000520 W KR2021000520 W KR 2021000520W WO 2021172753 A1 WO2021172753 A1 WO 2021172753A1
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Prior art keywords
substrate
nozzle
spinning solution
nanofiber layer
electrospinning
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English (en)
Korean (ko)
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이충원
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D39/00—Filtering material for liquid or gaseous fluids
    • B01D39/14—Other self-supporting filtering material ; Other filtering material
    • B01D39/16—Other self-supporting filtering material ; Other filtering material of organic material, e.g. synthetic fibres
    • B01D39/1607—Other self-supporting filtering material ; Other filtering material of organic material, e.g. synthetic fibres the material being fibrous
    • B01D39/1623—Other self-supporting filtering material ; Other filtering material of organic material, e.g. synthetic fibres the material being fibrous of synthetic origin
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D39/00—Filtering material for liquid or gaseous fluids
    • B01D39/14—Other self-supporting filtering material ; Other filtering material
    • B01D39/16—Other self-supporting filtering material ; Other filtering material of organic material, e.g. synthetic fibres
    • D—TEXTILES; PAPER
    • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
    • D01D5/00—Formation of filaments, threads, or the like
    • D—TEXTILES; PAPER
    • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
    • D01D5/00—Formation of filaments, threads, or the like
    • D01D5/0007—Electro-spinning
    • D01D5/0015—Electro-spinning characterised by the initial state of the material
    • D01D5/003—Electro-spinning characterised by the initial state of the material the material being a polymer solution or dispersion
    • D—TEXTILES; PAPER
    • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
    • D01D5/00—Formation of filaments, threads, or the like
    • D01D5/0007—Electro-spinning
    • D01D5/0061—Electro-spinning characterised by the electro-spinning apparatus
    • D01D5/0069—Electro-spinning characterised by the electro-spinning apparatus characterised by the spinning section, e.g. capillary tube, protrusion or pin
    • D—TEXTILES; PAPER
    • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
    • D01D5/00—Formation of filaments, threads, or the like
    • D01D5/0007—Electro-spinning
    • D01D5/0061—Electro-spinning characterised by the electro-spinning apparatus
    • D01D5/0076—Electro-spinning characterised by the electro-spinning apparatus characterised by the collecting device, e.g. drum, wheel, endless belt, plate or grid
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
    • B01D2239/02—Types of fibres, filaments or particles, self-supporting or supported materials
    • B01D2239/025—Types of fibres, filaments or particles, self-supporting or supported materials comprising nanofibres
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
    • B01D2239/06—Filter cloth, e.g. knitted, woven non-woven; self-supported material
    • B01D2239/0604—Arrangement of the fibres in the filtering material
    • B01D2239/0631—Electro-spun
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
    • B01D2239/10—Filtering material manufacturing

Definitions

  • the present invention relates to a nanofilter, and more particularly, to a nanofilter having improved efficiency and lifespan of the filter by controlling the diameter of the nanofiber formed by adjusting the nozzle diameter of the nozzle block, and a method for manufacturing the same.
  • a filter capable of discharging filtered clean air and clean water by separating impurities and contaminants is mainly used in these devices.
  • the filter includes one or more nanofibers in the form of a web together with a substrate material in the filter structure.
  • the nanofiber is a fiber having a diameter of several hundred nanometers (nm) or less, and refers to a fiber material of a new concept having a function and performance different from that of a conventional fiber material. Since the nanofiber includes a plurality of pores, the nanofiber filter including these nanofibers can separate dozens of nano-sized or larger particles, and can purify a large amount of water in a short period of time or remove particulates in the air. It has excellent filtration ability to effectively filter out and high particle trapping ability.
  • the conventional nanofiber filter used in water treatment has a problem in that the separation efficiency is significantly reduced as the surface of the nanofiber filter is contaminated by microorganisms to be separated when used for a long time, thereby increasing the energy consumption and the consumption of the filter.
  • the present invention is to provide a nanofilter with improved efficiency and lifespan of the filter and a method for manufacturing the same by adjusting the diameter of the nanofiber formed by adjusting the nozzle diameter of the nozzle block The purpose.
  • a method of manufacturing a nanofilter according to an embodiment of the present invention comprises: supplying a spinning solution obtained by dissolving a polymer in an organic solvent to a spinning solution main tank; supplying the substrate onto the collector of the electrospinning apparatus; The spinning liquid supplied to the spinning liquid main tank is quantitatively supplied into a plurality of nozzles located in the nozzle block through a metering pump; And each spinning liquid supplied from each nozzle is spun on a substrate supplied to a collector spaced apart from the nozzle at a predetermined distance through the nozzle to form a nanofiber layer on the substrate, wherein the nozzle is the process of the substrate A plurality of nozzles are arranged in the direction, and the nozzle diameter of each nozzle may be gradually decreased in the moving direction of the substrate.
  • the nozzles are arranged in k rows in the moving direction of the substrate, the diameter of the k-row nozzles based on the moving direction of the substrate is smaller than the diameter of the k-1 row nozzles, and k rows based on the moving direction of the substrate
  • the number of nozzles may be greater than the number of nozzles in k-1 row.
  • the electrospinning device collects the spinning solution that overflowed without being spun from the nozzle in the overflow spinning solution storage tank, and transfers the moisture contained in the solvent in the spinning solution to the receiving tank while controlling the vacuum and temperature and stirring. It may include a moisture removal device.
  • the spinning liquid supplied to each of the nozzles may be the same or different from each other.
  • the polymer is polylactic acid (PLA), polycarbonate (PC), polyvinylidene fluoride (PVDF), polypropylene (PP), polyethylene terephthalate (PET), polyethersulfone (PES), polyamide, polyvinyl acetate , polymethyl methacrylate, polyacrylonitrile (PAN), polyurethane (PUR), polybutylene terephthalate (PBT), polyvinylbutylral, polyvinyl chloride, polyethyleneimine, polyvinyl acetate (PVAc), polyethylene It may be one or two or more selected from the group consisting of naphthalate (PEN), polyvinyl alcohol (PVA), polyethyleneimide (PEI), polycaprolactone (PCL), and polylactic acid glyceryl acid (PLGA).
  • PPA polylactic acid
  • PC polycarbonate
  • PVDF polyvinylidene fluoride
  • PP polypropylene
  • PET polyethylene terephthalate
  • PES
  • the organic solvent is methylene chloride, phenol, formic acid, sulfuric acid, m-cresol, tifluoroacetandhydride/dichloromethane, water, N-methylmorpholine N-oxide, chloroform, tetrahydrofuran, methyl Isobutyl ketone, methyl ethyl ketone, m-butyl alcohol, isobutyl alcohol, isopropyl alcohol, methyl alcohol, ethanol, hexane, tetrachloroethylene, acetone, propylene glycol, diethylene glycol, ethylene glycol, trichloroethylene, di Chloromethane, toluene, xylene, cyclohexanone, cyclohexane, n-butyl acetate, ethyl acetate, butyl cellosalb, 2-ethoxyethanol acetate, 2-ethoxyethanol, dimethylformamide and dimethylacetamide It
  • the nano filter according to an embodiment of the present invention is manufactured by the above manufacturing method, the substrate; And the nanofiber layer formed on the substrate is a laminated structure, and the nanofiber layer may have a structure in which the diameter of the nanofibers is gradually reduced in the thickness direction of the nanofiber layer on the substrate.
  • the method for manufacturing a nanofilter according to an embodiment of the present invention uses a nozzle block in which the nozzle diameter is gradually reduced in the moving direction of the substrate, thereby continuously and easily increasing the diameter of the nanofiber in the thickness direction of the nanofiber layer formed on the substrate. can be adjusted
  • the nanofilter having a structure in which the diameter of the nanofiber gradually decreases in the thickness direction has the effect of improving the efficiency of the filter and improving the lifespan.
  • FIG. 1 is a view schematically showing an electrospinning apparatus according to an embodiment of the present invention.
  • Figure 2 is a view schematically showing the nozzle plate and the nozzle tube of the electrospinning apparatus according to an embodiment of the present invention.
  • Figure 3 is a view schematically showing a water removal device of the electrospinning apparatus according to an embodiment of the present invention.
  • first, second, etc. may be used to describe various elements, but the elements should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, a first component may be referred to as a second component, and similarly, a second component may also be referred to as a first component.
  • the singular expression includes the plural expression unless the context clearly dictates otherwise.
  • “under” another part this includes not only cases where it is “directly under” another part, but also cases where another part is in between.
  • “on” may include the case of being disposed not only on the upper part but also on the lower part.
  • a nano filter according to an embodiment includes a substrate; and a nanofiber layer formed by electrospinning a spinning solution on the substrate.
  • the substrate is a support for the filter to maintain the shape stability of the filter.
  • the substrate is preferably a polyethylene terephthalate substrate, but is not limited thereto.
  • the polyethylene terephthalate substrate usually has a basis weight of 15 to 150 g/m 2 , where it is difficult to serve as a support when the basis weight is less than 15 g/m 2 , and 150 g/m If it is more than 2, the filtration efficiency is lowered, and there is a problem in that the processability is lowered in manufacturing the filter.
  • the polyethylene terephthalate substrate of the present invention as described above may use a low melting point polyethylene terephthalate (Low Melt Polyethylene terephthalate, LM PET) substrate.
  • the low-melting-point polyethylene terephthalate substrate may be of a sheath-core, side by side, or C-type type.
  • the sheath portion is low-melting polyethylene terephthalate, and the core portion is composed of general polyethylene terephthalate.
  • the sheath portion is composed of about 10 to 90 wt%, and the core is composed of about 90 to 10 wt%.
  • the sheath portion acts as a thermal binder forming the outer surface of the binder fiber and has a melting point of about 80 to 150° C. and the core having a melting point of about 160 to 250° C.
  • the sheath-core low-melting-point polyethylene terephthalate substrate used as an embodiment in the present invention includes an amorphous polyester copolymer whose melting point does not appear in the sheath portion by a conventional melting-point analyzer, and is preferably relatively relative as a core component. It is a heat-adhesive composite fiber using high melting point components.
  • the polyester copolymer contained in the sheath portion is a co-polyester in which 50 to 70 mol% are polyethylene terephthalate units. 30 to 50 mol% is preferably isophthalic acid as the copolymerized acid component, but other common dicarboxylic acids are all possible.
  • a polymer having a melting point of 160° C. or higher is suitable, and examples thereof include polyethylene terephthalate, polybutylene terephthalate, polyamide, polyethylene terephthalate copolymer, and polypropylene.
  • the low melting point polyethylene terephthalate substrate is 50 to 100 g/m 2 , preferably 60 to 80 g/m 2 .
  • adhesion with the nanofiber layer located on the substrate may be imparted. This has the effect of preventing the filtration efficiency from being lowered while preventing the separation between the filter layers without using a separate adhesive.
  • the nanofiber layer according to the present invention is characterized in that it is formed by electrospinning a spinning solution on the substrate.
  • the nanofiber layer may have a structure in which the diameter of the nanofiber is gradually decreased in the thickness direction of the nanofiber layer in the substrate. More specifically, as shown in FIG. 1, it is a multi-layer structure in which k nanofiber layers are formed on the substrate, and the first nanofiber layer formed on the substrate may have an average diameter of the nanofibers of 250 to 500 nm, k The second nanofiber layer may have an average diameter of the nanofibers of 80 to 120 nm. As such, as the nanofiber layer formed on the substrate gradually decreases in diameter in the thickness direction, the efficiency of the filter may be improved and the lifespan may be improved.
  • the thickness of the nanofiber layer is preferably 0.1 to 5 ⁇ m
  • the basis weight is preferably 0.1 to 10 g/m 2 .
  • the thickness of the nanofiber layer is less than 0.1 ⁇ m, it is difficult to peel from the support, and when it exceeds 5 ⁇ m, there is a problem of poor processability and economical efficiency
  • the basis weight of the nanofiber layer is less than 0.1 g/m 2 , the filtration efficiency is reduced, 10 g If /m 2 is exceeded, a problem of poor processability and economic feasibility occurs.
  • the preparation of the nanofiber layer as described above can be achieved by using an electrospinning device.
  • electrospinning uses a high voltage applied to a polymer spinning solution to eject fine fibers. That is, it is a method of obtaining a nanofiber in the form of a nonwoven fabric by instantaneously spinning into a fiber form using a polymer in a low viscosity state by electrostatic force. Electrospinning has the characteristic of making fibers having a diameter of nanometers beyond micrometers. In the case of nanofibers, since they have a larger surface area than conventional fibers, there is an advantage in that filtration efficiency can be increased when using them as filters.
  • Electrospinning is classified into bottom-up electrospinning and top-down electrospinning.
  • the bottom-up electrospinning uses a bottom-up electrospinning device.
  • the spinning nozzle is located at the bottom, and the collector is located at the top spaced apart from the nozzle.
  • the polymer spinning solution is electrospun from the spinning nozzle at the bottom to form nanofibers on the collector at the top.
  • the bottom-up electrospinning apparatus there is an advantage in that it is possible to produce high-quality nanofibers by effectively preventing the droplet phenomenon.
  • all of the polymer spinning solution is not nanofiberized, and there are problems such as the remaining spinning solution flowing down the nozzle wall.
  • the top-down electrospinning uses a top-down electrospinning device, and the top-down electrospinning device has a spinning nozzle located at an upper end, and a collector is located at a lower end spaced apart from the nozzle.
  • the polymer spinning solution is electrospun from the spinning nozzle at the top to form nanofibers on the collector at the bottom.
  • all of the polymer spinning solution to be spun into nanofibers has the advantage of high productivity.
  • the electrospinning apparatus of the present invention is a spinning liquid main tank filled with a spinning liquid therein, a metering pump for quantitative supply of a polymer spinning liquid filled in the spinning liquid main tank, and a polymer spinning liquid in the spinning liquid main tank, , a plurality of nozzles in the form of pins are arranged, and a nozzle plate including a recovery device for recovering the solution remaining after spinning and a nozzle block in which a plurality of nozzle tubes are arranged, and nanofibers spun by being located at the lower end or upper end of the nozzle It is configured to include a block accommodating therein a collector spaced apart from the nozzle and a voltage generating device for generating a voltage in the collector, and a case composed of a conductor or a non-conductor in the block in order to integrate them.
  • the electrospinning device uses two main tanks for spinning solution.
  • it is also possible to use one main tank for spinning solution divide the inner space into two compartments, and then fill each divided space with two different types of spinning solution, respectively.
  • the inside of the spinning liquid main tank may be divided into three or more spaces, and three or more spinning liquid main tanks may be provided to provide each polymer solution.
  • the electrospinning device is continuously quantitatively supplied to a plurality of nozzles to which a high voltage is applied through a precision metering pump in which the spinning solution filled in the spinning solution main tank in the block is supplied, and supplied to the nozzles.
  • the spinning solution of the polymer used is spun and focused on a long sheet or substrate on a collector to which a high voltage is applied through a nozzle to prepare a nanofiber layer.
  • the spinning liquid supplied to each of the spinning liquid main tank is continuously quantitatively supplied into a plurality of nozzles located in the nozzle block through a precision metering pump.
  • Each spinning solution supplied from each nozzle is focused on a support while being spun and focused on a long sheet or substrate on a collector to which a high voltage is applied through the nozzle.
  • the nozzle block may be of a form in which a plurality of plate and tubular types are installed, and the nozzle plate and the nozzle tube move up and down, left and right, and can be operated individually.
  • the supply of the spinning solution to the nozzle plate and the nozzle tube can be controlled by the micro pressure formed by using a precision metering pump to control the supply and spinning of the solution.
  • the nozzles installed on the nozzle plate and the nozzle tube may have different diameters, the nozzle spacing may be adjusted, and the amount of radiation may be changed.
  • the nozzle block may have a structure in which two nozzle plates and three nozzle tubes are alternately arranged as shown in FIG. 1 , but is not limited thereto.
  • the diameter of the nanofibers emitted by the nozzle plate may be relatively larger than the diameter of the nanofibers emitted by the nozzle tube.
  • the nozzles may be arranged in k rows in the moving direction of the substrate, and the diameter of the k-row nozzles based on the moving direction of the substrate is smaller than the diameter of the k-1 row nozzles, and the k-rows based on the moving direction of the substrate.
  • the number of nozzles may be greater than the number of nozzles in the k-1 row. Due to this, as the nanofiber layer formed on the substrate gradually decreases in diameter in the thickness direction, the efficiency of the filter can be improved and the lifespan can be improved.
  • both ends of the nozzle plate and the nozzle pipe may be connected to a device for regulating the pressure in the pipe and recovering the used spinning solution.
  • the plurality of nozzle tubes and the nozzle plate each have a metering pump and a control valve, and the spinning liquid supplied to each nozzle plate and the nozzle tube may be the same or different from each other.
  • two or more different polymer spinning solutions may be spun within one nozzle plate (or nozzle tube), and different types of polymer spinning solutions may be spun for each nozzle plate (or nozzle pipe). .
  • a voltage of 1 kV or more, more preferably 70 kV or more, generated by a voltage generator is applied to the nozzle block and the collector.
  • a voltage of 1 kV or more, more preferably 70 kV or more, generated by a voltage generator is applied to the nozzle block and the collector.
  • the front end of the electrospinning device is provided with a supply roller (Unwinder) for supplying a substrate (long sheet) on which the polymer spinning solution is spun from the nozzle block to form a laminated nanofiber, and a substrate on which the nanofiber is laminated at the rear end
  • a supply roller Unwinder
  • Rewinder winding roller
  • the substrate (long sheet) is provided to prevent sagging of the nanofibers and transport.
  • the substrate (long sheet) is wound on one side and the other side by a supply roller provided at the front end of the electrospinning device and a winding roller provided at the rear end.
  • auxiliary belts are respectively provided between the collector and the base material (long sheet), and the base material (long sheet) on which the nanofibers are laminated by being accumulated on each collector through each auxiliary belt is transported in the horizontal direction. That is, the auxiliary belt rotates in synchronization with the feed speed of the substrate (long sheet), and has a roller for the auxiliary belt for driving the auxiliary belt.
  • the roller for the auxiliary belt is an automatic roller having extremely low frictional force of two or more. Since the auxiliary belt is provided between the collector and the base material (long sheet), the base material (long sheet) is smoothly transferred without being attracted to the collector to which a high voltage is applied.
  • the substrate passes through the electrospinning section, it receives resistance by the electromagnetic field and is affected by contraction and expansion, which adversely affects the quality of the nanofiber and the transfer and winding of the fabric.
  • the form of the wire belt, which is an auxiliary belt is preferably a seamless structure for a membrane and a liquid filter, and a seamless structure for a general filter.
  • the spinning solution filled in the spinning solution main tank in the nozzle block of the electrospinning device is spun on the substrate (long sheet) located on the collector through the nozzle, and on the substrate (long sheet)
  • the nanofibers are laminated as the spun spinning solution is accumulated.
  • the auxiliary belt is driven by the rotation of the auxiliary belt rollers provided on both sides of the collector, and the substrate (long sheet) is transported while being positioned in the nozzle block at the rear end of the electrospinning device to repeatedly perform the above process.
  • the nozzle block is composed of a plurality of nozzles arranged upward or downward from the discharge port for the spinning solution, a plate or tube body in which the nozzles are arranged in a line, a main tank for spinning solution, and a pipe for spinning solution.
  • the spinning solution main tank connected to the spinning solution main tank to receive and store the spinning solution supplies the spinning solution to the nozzle through the spinning solution distribution pipe by the metering pump for the discharge amount of the solution, so that spinning proceeds.
  • the plate body or pipe body comprising a plurality of nozzles in a row receives the same spinning solution from the spinning solution storage tank, but a plurality of spinning solution main tanks are provided and each plate or pipe body is supplied with different types of polymers. It is also possible that different types of spinning solutions are supplied and spun.
  • the nozzles can have different diameters, the nozzle spacing is also controlled, and the radiation amount can be reduced, and the diameter of the nanofiber stack can also be adjusted for each layer.
  • the solution that is not nanofiberized and overflowed is moved to the overflow solution storage tank.
  • the overflow solution storage tank is connected to the spinning solution main tank, so the overflow solution can be reused for spinning.
  • the solution overflowed without spinning contains moisture when in contact with air, and if the moisture content in the solution increases by a certain ratio (2.5% or more), it affects product quality, such as causing pinholes during spinning. Therefore, when the solution overflowed without spinning is stored, it is necessary to maintain the moisture content below a certain ratio.
  • the electrospinning device of the present invention may include a moisture removal device to maintain a moisture content suitable for electrospinning.
  • This water removal device collects the overflowed solution (recovery solution) that cannot be nanofibrillated in a water removal pressure tank and separates the solvent containing water in the solution through vacuum, temperature control, and stirring process in a separate receiving tank (solvent condensation tank) It is structured to receive At this time, the solvent containing water has a solvent ratio of about 60 to 75%, and can be reused through a reprocessing process through a solvent condensation tank.
  • the water removal device is connected to the general solution supply line control device, and the recovered solution maintains a moisture content suitable for electrospinning through the water removal pressure tank, and then goes through the calibration tank and then transferred to the solution service tank. , which can be reused for radiation.
  • Service tank ⁇ pressurized tank ⁇ solution supply pipe ⁇ nozzle plate or nozzle pipe ⁇ (recovery tank) ⁇ water removal pressure tank ⁇ calibration tank ⁇ service tank
  • the rear end of the electrospinning apparatus of the present invention may include a plurality of multi-stage heating rolls having a structure capable of temperature control and compression for the purpose of removing residual solvent remaining in the fabric and the collected nanofibers when passing through the electrospinning section. have.
  • the fabric and nanofibers After selectively passing through a plurality of multi-stage heating rolls, the fabric and nanofibers pass through a physical surface treatment (UV, laser, plasma irradiation, etc.) section again to modify the surface of the nanofiber and Alternatively, the adhesion between the nanofiber and the nanofiber may be improved.
  • a physical surface treatment UV, laser, plasma irradiation, etc.
  • a laminating device is installed at the rear end of the electrospinning device of the present invention.
  • the laminating device applies heat and pressure, through which the substrate (long sheet) and the nanofiber are adhered, and then wound on a winding roller to prepare a nanofiber layer.
  • the electrospinning device can increase the collection area to make the integration density of the nanofibers uniform, and effectively prevent the droplet phenomenon to improve the quality of the nanofiber, and the fiber formation effect by electric force is increased to increase the nanofiber Fibers can be mass-produced.
  • the material and the electrospinning condition can be adjusted differently in the electrospinning in the nozzle block provided with a nozzle composed of a plurality of pins, the width and thickness of the long sheet can be freely changed and adjusted.
  • the electrospinning apparatus of the present invention may include a constant temperature and humidity constant.
  • the thermo-hygrostat adjusts the temperature and humidity during the electrospinning process, operates to change the size of the fiber diameter at the same time, and removes and treats the solvent generated during the process and can be reused.
  • the electrospinning apparatus of the present invention may include a temperature control control device for adjusting the viscosity with a temperature control control device in order to maintain the fiber viscosity suitable for electrospinning.
  • both or any one of a heating device capable of maintaining a low viscosity of a high viscosity polymer spinning solution reused through overflow and a cooling device capable of maintaining a high viscosity of a relatively low viscosity polymer spinning solution can be provided.
  • the temperature in the electrospinning region changes the surface tension of the spinning solution by changing the viscosity of the spinning solution, so the diameter of the spun nanofiber will affect
  • nanofibers having a relatively thin fiber diameter are made, and when the viscosity of the solution is high because the temperature is relatively low, nanofibers having a relatively thick fiber diameter are made.
  • the concentration measuring device for measuring the concentration has a contact type and a non-contact type that directly contact the solution.
  • a contact type a capillary type concentration measuring device, a disk (DISC) type concentration measuring device, etc. can be used.
  • a density measuring device or a density measuring device using infrared rays may be used.
  • the heating device of the present invention may be composed of an electric heater, a hot water circulation device or a hot air circulation device, and in addition, devices capable of increasing the temperature in the same range as the above devices may be borrowed.
  • an electric heater may be used in the form of a hot wire, and a coil-type hot wire may be mounted inside the tube or plate body of the nozzle block, which is also deformable in the form of a jacket.
  • a configuration of a linear hot wire and a U-shaped pipe it is possible to have a configuration of a linear hot wire and a U-shaped pipe.
  • the heating device as described above may be provided in any one or more of a nozzle block for spinning a polymer spinning solution, a tank for storing a polymer spinning solution, and an overflow system.
  • cooling means including a chilling device may be used, and a means for maintaining a certain viscosity of the polymer spinning solution is generally applicable.
  • the cooling device may be provided in any one or more of the nozzle block, the tank, and the overflow system in the same way as the heating device, and is used to maintain a certain viscosity of the polymer spinning solution.
  • the viscosity of the polymer spinning solution of the present invention is preferably 1,000 to 5,000 cps, more preferably 1,000 to 3,000 cps.
  • the viscosity is 1,000 cps or less, the quality of the nanofibers electrospun and laminated is poor, and when the viscosity is 3,000 cps or more, the discharge of the polymer spinning solution from the nozzle during electrospinning is not easy, and the production speed is slowed down.
  • the viscosity of the polymer spinning solution is constant as the electrospinning progresses, so the spinning efficiency is excellent during electrospinning, and at the same time, the concentration of the polymer spinning solution increases, and the amount of solids excluding the solvent among the nanofibers accumulated in the collector increases. This has the effect of increasing productivity.
  • the amount of residual solvent in the nanofibers using electrospinning is less than in the case of using conventional electrospinning, so that nanofibers of excellent quality can be manufactured.
  • the temperature control control device of the present invention is a manual type that allows the operator to control the viscosity of the polymer spinning solution through the temperature control of the nozzle block or the spinning solution main tank by measuring the concentration of the intermediate tank offline, and at the same time, It includes an automatic type that can adjust the temperature of the solution according to the concentration measurement through an online automatic control system.
  • the temperature for performing electrospinning is 20 to 60°C.
  • the temperature for electrospinning is raised to 60° C., the amount of polymer solids in the polymer spinning solution can be increased, and thus productivity can be increased.
  • the electrospinning condition in the present invention is preferably a humidity of 40% or more.
  • polylactic acid PLA
  • PC polycarbonate
  • PVDF polyvinylidene fluoride
  • PP polypropylene
  • PET polyethylene terephthalate
  • PES polyether Sulfone
  • polyamide polyvinyl acetate, polymethyl methacrylate, polyacrylonitrile (PAN), polyurethane (PUR), polybutylene terephthalate (PBT), polyvinyl butyral, polyvinyl chloride
  • Examples include polyethyleneimine, polyvinyl acetate (PVAc), polyethylene naphthalate (PEN), polyvinyl alcohol (PVA), polyethyleneimide (PEI), polycaprolactone (PCL), and polylactic acid glycerol (PLGA).
  • PVAc polyethylene naphthalate
  • PEN polyvinyl alcohol
  • PVA polyethyleneimide
  • PCL polycaprolactone
  • PLGA polylactic acid glycerol
  • biodegradable polymer As the material of the polymer, it is preferable to use a biodegradable polymer as the material of the polymer.
  • the biodegradable polymer used in the present invention is PHB (poly-hydroxy butyrate), PHBV (3-hydroxy butyrate-co-3-hydroxy valerate), PGA [(poly)glycolic acid], PLA [(poly) lactic acid], PLGA (polylactic-co-glycolic acid), PCL [poly(e-caprolactone)], polydioxanone, polyorthoester, polyanhydride, ⁇ -PGA, gelatin ), silk, collagen, cellulose, alginic acid and hyaluronic acid may be selected from the group consisting of.
  • the polymer spinning solution is a solution in which the polymer, which is a synthetic resin material capable of electrospinning, is dissolved in a suitable solvent
  • the type of solvent is not limited as long as it can dissolve the polymer, for example, phenol, formic acid, sulfuric acid, m-cresol, tifluoroacetandhydride/dichloromethane, water, N-methylmorpholine N-oxide, chloroform, tetrahydrofuran and aliphatic ketone groups methylisobutylketone, methylethylketone, aliphatic hydroxyl group group m-butyl alcohol, isobutyl alcohol, isopropyl alcohol, methyl alcohol, ethanol, aliphatic compounds hexane, tetrachloroethylene, acetone, glycol group, propylene glycol, diethylene glycol, ethylene glycol, halogen compound group, trichloro Ethylene, dichloromethan
  • ком ⁇ онентs can be used as amides, and a plurality of types of solvents can be mixed and used. It is preferable to contain additives, such as an electroconductivity improving agent, in a spinning liquid.
  • a preferred solvent is dimethylacetamide.
  • the additive is preferably tetrabutylammonium perchlorate (TBAP).
  • the content of the polymer in the polymer spinning solution is preferably 10 to 35% by weight. If the content of the polymer is less than 10% by weight, the density of the nanofiber layer may not be uniform, and if it is 35% by weight, there is a problem in that the radioactivity is lowered.
  • a method of manufacturing a nano filter comprises: supplying a spinning solution obtained by dissolving a polymer in an organic solvent to a spinning solution main tank; supplying the substrate onto the collector of the electrospinning apparatus; The spinning liquid supplied to the spinning liquid main tank is quantitatively supplied into a plurality of nozzles located in the nozzle block through a metering pump; And each spinning liquid supplied from each nozzle is spun on a substrate supplied to a collector spaced apart from the nozzle at a predetermined distance through the nozzle to form a nanofiber layer on the substrate, wherein the nozzle is the process of the substrate A plurality of nozzles are arranged in the direction, and the nozzle diameter is gradually decreased in the moving direction of the substrate.
  • a polymer spinning solution in which a polymer is dissolved in an organic solvent is supplied to a spinning solution main tank connected to a unit of an electrospinning device, respectively, and the polymer spinning solution supplied to the spinning solution main tank is a nozzle to which a high voltage is applied through a metering pump It is continuously metered into multiple nozzles of the block.
  • the polymer spinning solution supplied from each nozzle is electrospun and focused on a substrate positioned on a collector to which a high voltage is applied through the nozzle to form a laminated nanofiber layer.
  • the electrospinning may be performed under a voltage of 40 to 60 kV, a fluid velocity of 0.1 to 5 ml/h, a spinning distance of 3 to 50 cm, room temperature conditions, and relative humidity of 30 to 50%.
  • the content of the polymer in the spinning solution may be 10 to 35% by weight.
  • the substrate on which the nanofiber layer is laminated in each unit of the electrospinning device is transported by the rotation of the supply roller operated by the driving of the motor and the auxiliary transport device driven by the rotation of the supply roller, and repeating the above process
  • the nanofiber layer is continuously electrospun and laminated on the substrate.
  • the thickness of the nanofiber layer prepared as described above is preferably 0.1 to 5 ⁇ m, and the basis weight is preferably 0.1 to 10 g/m 2 .
  • the thickness of the nanofiber layer is less than 0.1 ⁇ m, it is difficult to peel from the support, and when it exceeds 5 ⁇ m, there is a problem in processability and economic efficiency, and when the basis weight of the nanofiber layer is less than 0.1 g/m 2 , the filtration efficiency is reduced, If /m 2 is exceeded, there is a problem of poor processability and economical efficiency.
  • a plurality of nanofiber layers having different fiber diameters can be continuously laminated on the substrate.
  • the nanofiber layer may have a structure in which the diameter of the nanofiber is gradually decreased in the thickness direction of the nanofiber layer in the substrate. More specifically, it is a multilayer structure in which k nanofiber layers are formed on the substrate, the first nanofiber layer formed on the substrate may have an average diameter of the nanofibers of 250 to 500 nm, and the kth nanofiber layer is the average of the nanofibers The diameter may be 80-120 nm. As such, as the nanofiber layer formed on the substrate gradually decreases in diameter in the thickness direction, the efficiency of the filter may be improved and the lifespan may be improved.
  • two or more different polymer spinning solutions may be spun within one nozzle plate (or nozzle tube), and different types of polymer spinning solutions may be spun for each nozzle plate (or nozzle pipe).
  • the manufacturing method of the nano-filter comprises the steps of dissolving a polymer in an organic solvent to prepare first and second spinning solutions; forming a first nanofiber layer by electrospinning the first spinning solution using an electrospinning device; manufacturing a nanofilter by electrospinning the second spinning solution on the first nanofiber layer to form a second nanofiber layer; and removing the residual solvent of the nano-filter by passing the nano-filter through a multi-stage heating roll, and adhering the first nano-fiber layer and the second nano-fiber layer.
  • the present invention is a method for multi-bonding nanofibers in a real-time continuous process. may include technology.
  • the present invention can be bonded to the nanofibers spun while passing through the spinning section of the separate fabric to which the adhesive is spun/applied in a real-time continuous process.
  • the fabric on which the adhesive has been spun or applied is a fabric that has been pretreated with an adhesive before the electrospinning process, or the adhesive is spun on the fabric at the front end in the spinning section and continuously electrospinning the nanofibers directly on the fabric, While passing through the spinning section, continuous real-time work can be performed with 2 or 3 layers in a row.
  • the polymer used as the adhesive is not particularly limited, but it is preferably at least one selected from the group consisting of low melting point polyurethane, low melting point polyester, and low melting point polyvinylidene fluoride, which are low melting point polymers.
  • a spinning solution obtained by dissolving 15 wt% of polylactic acid (PLA) in methylene chloride was prepared and put into a spinning solution main tank connected to an electrospinning device.
  • the nozzle block of the electrospinning apparatus used a structure in which two nozzle plates and three nozzle tubes are alternately arranged.
  • the distance between the electrode and the collector was 15 cm, the applied voltage 40 kV, the spinning solution flow rate 0.1 mL/h, and the room temperature and humidity were 40%.
  • a PLA nanofiber layer was formed.
  • electrospinning was performed under the conditions of 40 cm distance between the electrode and the collector, 40 kV of applied voltage, 0.1 mL/h of spinning solution flow rate, and 40% of room temperature and humidity, and the average diameter of the fibers on the first PLA nanofiber layer.
  • a nano-filter was prepared by forming a second PLA nanofiber layer of 150 nm.
  • the prepared nanofilter was passed through a multi-stage heating roll to remove the residual solvent of the nanofilter, and at the same time, the PET substrate, the first PLA nanofiber layer and the second PLA nanofiber layer were adhered to each other to finally prepare a nanofilter.
  • a first spinning solution in which polylactic acid (PLA) was dissolved in methylene chloride at 15% by weight and a second spinning solution in which polylactate-co-glycolate (PLGA) was dissolved in methylene chloride by 15% by weight were prepared.
  • the nozzle block of the electrospinning apparatus used a structure in which two nozzle plates and three nozzle tubes were alternately arranged, and the first spinning liquid was put into the spinning liquid tank connected to the nozzle plate, and the nozzle tube was connected The second spinning solution was put into the spinning solution tank.
  • the prepared nanofilter was passed through a multi-stage heating roll to remove the residual solvent of the nanofilter, and at the same time, a PET substrate, a PLA nanofiber layer, and a PLGA nanofiber layer were adhered to prepare a final nanofilter.
  • a spinning solution obtained by dissolving 15 wt% of polylactic acid (PLA) in methylene chloride was prepared and put into a spinning solution main tank connected to electrospinning.
  • the distance between the electrode and the collector was 15 cm, applied voltage 40 kV, spinning solution flow rate of 0.1 mL/h, room temperature and humidity were 40%, electrospinning was performed on the PET substrate to prepare a nano-filter having an average diameter of fibers of 300 nm.
  • a nanofilter having an average fiber diameter of 150 nm was manufactured through the same process as in Comparative Example 1, except that the distance between the electrode and the collector was adjusted to 40 cm.
  • the DOP test method was used to measure the efficiency of each of the nano-filters prepared in Examples and Comparative Examples.
  • the DOP test method is to measure the dioctylphthalate (DOP) efficiency with the automated filter analyzer (AFT) of TSI 3160 of TSI Incorporated.
  • DOP dioctylphthalate
  • AFT automated filter analyzer
  • the automated analyzer is a device that automatically measures the air speed, DOP filtration efficiency, air permeability (breathability), etc. by counting the DOP by making particles of a desired size and permeating it on the filter sheet, and is a very important device for high-efficiency filters.
  • DOP % efficiency is defined as:
  • Example 1 Example 2 Comparative Example 1 Comparative Example 2 0.35 ⁇ m DOP Filtration Efficiency (%) 95 95 71 75
  • the nano-filter prepared in the example of the present invention has superior filtration efficiency compared to the comparative example.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Textile Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Dispersion Chemistry (AREA)
  • Spinning Methods And Devices For Manufacturing Artificial Fibers (AREA)
  • Nonwoven Fabrics (AREA)

Abstract

La présente invention concerne un nanofiltre fabriqué par électrofilage et son procédé de fabrication, et plus spécifiquement, un nanofiltre et son procédé de fabrication dans lequel, en ajustant le diamètre d'une nanofibre formée par réglage d'un diamètre de buse d'un bloc de buses, l'efficacité et la durée de vie d'un filtre sont améliorées.
PCT/KR2021/000520 2020-02-25 2021-01-14 Nanofiltre ayant une efficacité de filtre améliorée et une durée de vie améliorée, et son procédé de fabrication Ceased WO2021172753A1 (fr)

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KR20230072102A (ko) * 2021-11-17 2023-05-24 한국과학기술연구원 나노섬유 매트, 나노섬유 매트 제조장치 및 방법

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KR102862498B1 (ko) * 2024-11-21 2025-09-24 하태성 식물유래 바이오매스를 이용한 친환경 에어필터제조방법 및 이에 의해 제조된 친환경 에어필터

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