KR100658499B1 - Method of manufacturing mats coated with nanofibers and mats manufactured thereby - Google Patents

Abstract

The present invention relates to a method for manufacturing a mat coated with nanofibers, and to a mat manufactured therefrom, wherein the polymer spinning solution in the polymer spinning solution main tank 4 is subjected to a high voltage and at least one unit block is placed in a horizontal or longitudinal direction. The collector 3, which is a cylindrical conductor, is rotated in a state in which a high voltage is applied through the nozzles 2a in the nozzle blocks 2, which are combined in a C-shape in an arranged state, and the one side is wrapped by the nozzle blocks 2. It is characterized in that the electrospun on the mat (6) passing through the coating the electrospun nanofiber on the mat (6), and then wound on the winding machine (9) using a transfer roller (8). .

The present invention can adjust the orientation angle of the coated nanofibers to the mat axis direction as desired by varying the rotational speed of the collector.

In addition, in the present invention, since the nozzle block 2 surrounds one side of the rotating cylindrical collector 3, a large amount of nozzles can be arranged in the transverse direction or the longitudinal direction of the nozzle block 2 in a very narrow space. The productivity (coating amount) per unit time can be improved, and the nozzle block 2 is composed of a plurality of unit blocks, so that the radiation amount can be easily controlled and the fiber forming ability is improved.

 Electrospinning, Mat, Coating, Composite Materials, Nanofiber, Rotary Collector, Nozzle Block

Description

Method for manufacturing mat coated with nanofibers and mat manufactured therefrom {Method of manufacturing mats coated with nanofibers and mats manufactured thereby}

1 is a schematic view of the manufacturing process of the nanofiber coated mat according to the present invention.

2 is a perspective view of a C-shaped nozzle block 2 composed of five unit blocks.

Figure 3 is a schematic view of the manufacturing process of the present invention for producing a nanofiber coated mat using two nozzle blocks and two collectors.

* Description of symbols on the main parts of the drawings

1: high voltage generator 2: cylindrical nozzle block

2a: nozzle 3: collector

4: Polymer spinning solution main tank 5: Mat feed roller

6: mat 7: nanofiber coated mat

8: feed roller 9: winding machine

A, B: polymer type

The present invention relates to a method for producing a nanofiber-coated mat using electrospinning and to a mat prepared therein, specifically, the present invention is one or more when coating the nanofiber on the mat using electrospinning By using C-shaped nozzle blocks in which unit blocks are arranged in a lateral or longitudinal direction, a large number of nozzles can be arranged in a unit space, thereby improving the amount of nanofiber coating per unit time even in a very small place. The present invention relates to a method of manufacturing a nanofiber-coated mat, which can freely adjust the angle of orientation of the coated nanofibers relative to the mat axis, to easily control the performance and properties of the nanofiber-coated mat.

In the present invention, the nanofiber means a fiber having a fiber diameter of 1,000 nm or less, more preferably 500 nm or less.

In addition, in the present invention, a mat means a two-dimensional fiber base such as a nonwoven fabric, a woven fabric, a knitted fabric, a membrane, and a braid.

Mats composed of nanofibers can be widely used for general clothing, artificial leather, filters, diapers, sanitary napkins, sutures, anti-adhesion agents, wiping cloths, artificial blood vessels, bone fixing devices, and especially for artificial leather. Very useful for

Korean Patent No. 422459 proposes a method of electrospinning a high molecular spinning liquid on a mat passing through an collector of an endless belt type as a prior art for manufacturing a nanofiber coated mat.

Specifically, the prior art continuously quantitatively supplies the polymer spinning liquid in the spinning liquid main tank into a plurality of nozzles to which a high voltage is applied through the metering pump, and continuously supplies the spinning liquid supplied to the nozzle to a high 5 kV or more through the nozzle. It is a method of manufacturing a mat coated with nanofibers by spinning and focusing on a mat passing through a collector of an endless belt type under voltage.

However, the conventional method has a very short radiation distance (distance between the nozzle and the collector) in the electrospinning process, and thus the method of stretching by applying a separate physical force is very limited, so the mechanical properties of the final product are very low. In addition, the method can not control the orientation angle of the nanofibers in the mat axial direction, there is a problem that the production (coating amount) per unit time is low because it is not possible to arrange a large number of nozzles in a narrow space.

On the other hand, when manufacturing a mat made of nanofibers, by placing the conductor wires on both sides of a non-conductor such as quartz by arranging the nanofibers in the fiber axis direction, and then electrospinning them, these conductor wires The arrangement of fibers has already been published (Dan Li, Yuliang Wang, and Younan Xia, Advanced Materials Vol 16 (4), pp361-366, 2004). However, this method is less likely to industrialize and is not a way to introduce the stretching force.

As described above, the conventionally known techniques are not able to arbitrarily adjust the orientation angle of the coated nanofibers with respect to the mat axis direction, and because a large amount of nozzles cannot be arranged in a narrow space, the production amount (coating amount) per unit time is increased. There was a problem of low fiber formation ability.

In the present invention, when manufacturing a nanofiber coated mat by the electrospinning method, a large amount of nozzles can be arranged even in a narrow space, so that the productivity (coating amount) per unit time is high, and the orientation angle of the nanofibers with respect to the mat axis direction is increased. It is intended to provide a method that can be easily adjusted.

In addition, the present invention is to provide a mat coated with nanofibers having physical properties suitable for various industrial materials such as artificial leather as well as filters, diapers, sanitary napkins, artificial blood vessels.

In the method of manufacturing the nanofiber coated mat of the present invention for achieving the above problems, the polymer spinning solution in the polymer spinning solution main tank (4) is subjected to high voltage and one or more unit blocks in the transverse or longitudinal direction The collector 3, which is a cylindrical conductor, is rotated in a state in which a high voltage is applied through the nozzles 2a in the nozzle blocks 2, which are combined in a C-shape in an arranged state, and the one side is wrapped by the nozzle blocks 2. Electrospinning on the mat (6) passing through the top to coat the nanofibers electrospun on the mat (6), and then using a transfer roller (8) to wind the mat (7) coated with nanofibers It is characterized by winding in (9).

In addition, the continuous mat of the present invention is characterized in that it is composed of the mat 6 and the nanofibers 2a coated on the mat 6.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

First, in the present invention, as shown in Fig. 1, the nozzle block in which the polymer spinning solution in the polymer spinning solution main tank 4 is combined in a C shape with one or more unit blocks arranged in the horizontal or longitudinal direction ( On the mat (6) by electrospinning on the mat (6) passing through the collector (3), which is a cylindrical conductor rotating on one side by the nozzle block through the nozzle (2a) in 2) The nanofibers coated on the electrospun.

1 is a process schematic diagram of the present invention.

As shown in FIG. 2, the nozzle block 2 has a high voltage applied thereto and is combined in a C shape with one or more unit blocks arranged in a lateral or longitudinal direction.

Fig. 2 is a perspective view of the C-shaped nozzle block 2 used in the present invention.

On the other hand, the collector (3) is a cylindrical conductor is rotated in a form wrapped on one side by the nozzle block (2) and is subjected to a high voltage.

The mat 6 is continuously supplied from the supply roller 5 onto the collector 3 as a two-dimensional fiber base such as nonwoven fabric, woven fabric, knitted fabric, membrane, braid or the like.

As described above, the present invention is characterized by simultaneously using the C-shaped nozzle block 2 and the rotating cylindrical collector 3 described above during electrospinning.

In order to uniformly coat the nanofibers on the mat 6 passing through the collector 3 during electrospinning, the nozzle block 2 preferably reciprocates from side to side based on the longitudinal direction of the collector 3. Do.

Next, the transfer roller 8 is used to wind the mat 7 coated with the nanofibers onto the winder 9.

The nanofiber coated mat 7 may be embossed or dried before being wound onto the winder 9.

Each of the C-shaped nozzle block 2 and the collector 3, which is a cylindrical conductor, may have a multilayer form divided into two or more layers by a non-conductive separator.

When the C-shaped nozzle block 2 and the collector 3 are multi-layered, they are separate or integral, and the length (height) of each layer constituting them may be different from each other.

Meanwhile, in the present invention, as shown in FIG. 3, two or more cylindrical nozzle blocks 2 and collectors 3 may be used to simultaneously manufacture two or more mats 7 coated with nanofibers.

Figure 3 is a schematic view of the manufacturing process of the present invention for producing a nanofiber coated mat using two nozzle blocks and two collectors, the reference numerals are omitted.

In this case, the same polymer spinning solution may be supplied to each of the two or more C-shaped nozzle blocks 2, or different polymer spinning solutions may be supplied to produce mats coated with different types of nanofibers.

It is also possible to produce a hybrid mat by laminating before winding up other types of mat manufactured simultaneously as described above.

The two or more C-shaped nozzle blocks 2 and the collector 3 may have the same diameter as each other, or may have different diameters from each other.

The nozzles 2a and the collectors 3 arranged on the C-shaped nozzle block are connected to the high voltage generator 1 to be subjected to a high voltage.

In addition, the upper surface of the collector (3) is attached to the non-conductor plate that serves to block the current flow at the same time to support the collector, the non-conductive plate is good to use a constant space to reduce the weight in the center You can get the result.

The material of the non-conductor plate is polypropylene, polyethylene, teflon, or a polymer of which they are composite materials. In order to facilitate the rotation through the motor, it is advantageous that the non-conductor plate has a free space.

The collector (3) is rotated by a rotating motor. If the collector is to be formed in multiple layers, it is necessary to prevent scattering of nanofibers during electrospinning and to prevent the phenomenon of electrospun fibers being coated on the mat 6 passing through the collector of another layer. It is more preferable to provide a separation plate (partitioner) which is a non-conductor.

Also, the height of the collector 3 is appropriately adjusted according to the width of the mat 6 to be coated.

The present invention can arrange a large number of nozzles in a narrow space can solve the limitation of mass production, which is a disadvantage of general electrospinning. In general, in the case of electrospinning with one nozzle in the electrospinning, the discharge amount is generally very small, 0.6-2.0mg / min. Therefore, for mass production, it is very important to increase the production efficiency by arranging a large number of nozzles in a narrow space. In this respect, the present invention has a great advantage.

On the other hand, in the present invention, it is possible to adjust the angle of orientation of the coated nanofibers on the mat axis by adjusting the rotation speed of the collector 3, it is possible to give the nanofibers coated mat (7) properties required for various applications have. For example, when the speed of rotation of the collector is adjusted to 5 m / sec, the orientation angle of the coated nanofibers with respect to the mat axis [the mat direction (machine direction)] is controlled to 3 ° or less so that the nanofiber coated mats (7 ) Physical properties are greatly improved.

In addition, the present invention may prepare an isotropic composite mat by stacking two or more mats having different orientation angles of the coated nanofibers with respect to the mat axis, respectively.

In the C-shaped nozzle block 2, the nozzles 2a are arranged diagonally in the transverse direction or the longitudinal direction, or arranged in a straight line in the transverse direction or the longitudinal direction.

The present invention can increase the production amount (coating amount) per unit time by arranging a large amount of nozzles in a narrow space. C-shaped nozzle block (2) may be composed of one or two or more unit blocks, the case of two or more unit blocks is convenient to replace the nozzle, easy to clean when changing the polymer to be used, In the electrospinning, the cone cone at the end of the nozzle can be stably formed, thereby improving the fiber forming ability.

On the other hand, the nozzle (2a) is arranged in the C-shaped nozzle block 2 as shown in Figure 2 and its length or diameter can be variously adjusted according to the width or thickness of the mat (6) to be coated . In addition, the length or diameter of the collector 3 can be freely selected according to the width or thickness of the mat 6 to be coated. The C-shaped nozzle block 2 and the collector 3 may be formed in a multilayer as described above. When the C-shaped nozzle block 2 is divided into two or more layers up and down, and each of the layers is supplied with a polymer spinning solution having different types or concentrations, the mat coated with nanofibers having different polymer types or nanofiber thicknesses (hereinafter referred to as "coating"). Mats "can be produced simultaneously. In addition, when these are laminated before winding, a hybrid mat can be easily produced.

In addition, the hybrid mat may be manufactured by supplying a polymer spinning solution having a different type or concentration to each unit block constituting the nozzle block 2.

The C-shaped nozzle block 2 is preferably placed on a fixed frame so that the distance between the nozzle 2a and the collector 3 can be arbitrarily adjusted.

In addition, it is possible to adjust the distance (radiation distance) between them by adjusting the diameter of the nozzle block 2 and the collector (3).

Polymer spinning solutions include polyester resins, nylon resins, polysulfone resins, polylactic acid, chitosan, collagen and cellulose. A component selected from the group consisting of fibrinogen, copolymers thereof, sol-gel containing metal components, copolymers thereof, and mixtures thereof may be used.

SUMMARY OF THE INVENTION The gist of the present invention is a cylindrical collector in which one or more unit blocks are rotated in a state in which one side is surrounded by the nozzle block 2 and the nozzle block 2 combined in a C-shape with one or more unit blocks arranged in a horizontal or longitudinal direction. The physical properties of the mat can be easily controlled by freely adjusting the angle of orientation of the coated nanofibers in the mat axial direction according to the rotational linear velocity of (3).

In general, it is very difficult to have a system capable of applying a separate physical force to the nanofibers that are electrospun during the electrospinning process. The reason is that the distance between the nozzle and the collector is very narrow (30 cm or less), so it is very difficult to apply mechanical force in a narrow space.

In the present invention, the nanofibers are arranged in the mat axis direction by using the centrifugal force of the rotating collector 3.

The present invention electrospun a polymer spinning solution onto a mat (6) passing through a collector (3) rotating through a plurality of nozzles arranged in a C-shaped nozzle block (2) to the nanofiber on the mat (6) Arrange them side by side.

It is a common phenomenon that the fiber produced by electrospinning proceeds a considerable part of crystallization according to the properties of the material. In addition, since the orientation of the nanofibers with respect to the mat axis is very low, the mechanical properties are very low, it is very difficult to increase the physical properties through a separate stretching process. The reason for this is that the crystals have already been formed, the elongation is remarkably lowered, and the mechanical properties are inevitably low because the orientation of the mat axis is low. However, by suppressing crystal formation during the electrospinning process and arranging the electrospun fibers uniformly in the mat axis direction, it is possible to manufacture a coating mat having excellent mechanical properties. When the nanofibers produced by electrospinning are focused on the mat 6 passing through the collector 3, which is a rotating cylindrical rotor, crystal formation can be suppressed and nanofibers are arranged in a line about the mat axis. Since it is possible to manufacture a coating mat excellent mechanical properties. If the collector's rotational linear velocity is too low, it is difficult to suppress crystal formation and it is not possible to orient the coated nanofibers in line with the mat axis. In the present invention, depending on the material, a coating mat having low crystallinity or partially / fully drawn nanofibers is well oriented with respect to the mat axis can be obtained. Therefore, the mechanical properties can be obtained much better than the properties obtained by the melt blown or spunbond method, and if necessary, the drawing mat is applied by using the linear speed difference of the roller when the stretching is required. It can manufacture.

In order to manufacture a hybrid type mat made of various widths or two or more kinds of polymers, the above-described multilayer C-shaped nozzle block and the corresponding multilayer cylindrical collector can be easily manufactured.

 The present invention can produce two or more kinds of coating mats 7 having different mat widths by varying the length (height) of each layer constituting the multilayer C-shaped nozzle block and the multilayer cylindrical collectors. In addition, two or more types of polymers may be used to simultaneously produce a mat 7 coated with nanofibers of different diameters.

In addition, in the present invention, a hybrid mat can be easily manufactured by supplying a different type of polymer spinning solution to each of the unit blocks constituting the C-shaped nozzle block 2.

Meanwhile, in the present invention, two or more nanofiber coated mats 7 are simultaneously manufactured using two or more cylindrical nozzle blocks 2 and two or more collectors 3, as shown in FIG. Hybrid mats can be prepared by lamination.

At this time, by supplying a polymer spinning solution having a different polymer type or concentration to each C-shaped nozzle block (2) it can be easily produced a hybrid (Hybrid) mat.

When the spinning solution of the same polymer having different concentrations is supplied to two or more C-shaped nozzle blocks 2, it is possible to manufacture a mat 7 coated with two or more kinds of nanofibers having different thicknesses.

In addition, by supplying different spinning solutions with different polymer types, the diameter of the nanofibers may be changed due to the difference in the types of polymers, thereby manufacturing a mat coated with two or more types of nanofibers having different diameters and polymer types.

 For example, in the case of nylon 6, the diameter of the nanofibers generally produced is about 100-300 nm, and in the case of polyurethane, about 200-500 nm. Therefore, it is very easy to manufacture a hybrid mat coated with two kinds of nanofibers having different diameters as well as nanofibers.

Also, in the present invention, two or more types of polymer spinning solutions are alternately electrospun through different nozzles in the same nozzle block to manufacture a hybrid mat of side by side type in which different nanofibers are regularly coated. It includes how to do it.

The nozzle 2 may have a core-shell structure.

The number of the said nozzles 2 is 1 or more, More preferably, it is 100 or more.

Next, as shown in FIG. 1, the nanofiber-coated mat 7 is wound around the winder 9 using the transfer roller 8. Before winding the mat 7 coated with nanofibers, it may be dried using a dryer or embossed using an embossing roller. In addition, the manufactured mat 7 may be impregnated with a thermoplastic resin or a thermosetting resin.

The nanofiber coated with the nanofiber 7 of the present invention manufactured by the manufacturing method of the present invention described above is characterized in that the mat 6 and the nanofibers coated on the mat (6).

The nanofibers coated on the mat 6 are hollow or in the form of pores on the surface, and are arranged at an orientation angle of 10 ° or less in the axial direction of the mat 6, so that the properties of the coating mat 7 are excellent. .

Hereinafter, the present invention will be described in detail through Examples and Comparative Examples. However, the present invention is not limited to the protection range by the following examples.

Example 1

A polymer spinning solution was prepared by dissolving nylon 66 resin having a relative viscosity of 3.0 in 96% sulfuric acid solution at a concentration of 15% by weight in formic acid / acetic acid (volume ratio: 70/30). The surface tension of the polymer spinning solution was 37 mN / m, the solution viscosity was 420 centipoise at room temperature, and the electrical conductivity was 340 mS / m.

As shown in FIG. 1, the nozzles 2a in the nozzle block 2 are combined in a C shape with 160 unit blocks having a length of 5 cm and arranged in the transverse direction. A high voltage is applied and one side is surrounded by the nozzle block 2, and a cylindrical conductor (stainless steel) collector 3 which rotates at a rotational linear speed of 18 m / min passes at a speed of 18 m / min. An electrospun onto a nonwoven fabric (weight: 15 g / m 2) was coated with the nanofibers electrospun on the nonwoven fabric.

The collector is rotated in connection with the rotary motor by a connecting rod, the length is 1.8m, the radius was 1.85m. The nozzle block 2 had a radius of 2.0 m and a length (mat width direction) of 1.8 m. 160 nozzles were horizontally arranged in one unit block constituting the nozzle block 2, so that the total number of nozzles in the nozzle block 2 was 11,520. During the electrospinning, the cylindrical nozzle block 2 was reciprocated at a speed of 3m / min to make the nanofiber lamination density uniform. The diameter of the nozzle was 1 mm, the voltage was 35 kV, and the spinning distance was 15 cm.

Next, the nonwoven fabric 7 coated with the nanofibers was wound on the winding machine 9 using the transfer roller 8, and the nanofibers having an average diameter of 184 nm had a coating amount of 0.42 g / m 2. Mat was prepared.

As a result of evaluating various properties of the manufactured mat, the air permeability was 11.5 cc / cm 2 / sec, the pressure loss was 6.2 mmH ₂ O, and the filtration efficiency was 99.999%.

In the present invention, various physical properties of the nanofiber coated mat (coating mat) were evaluated by the following method.

Air Permeability [cc / ㎠ / sec]

It was measured according to the KSK 0570 method.

The Fx 330 tester manufactured by Textest was used as the measuring device, the pressure was 125 Pa, and the measuring area was 38 cm 2.

Pressure drop [Pressure Drop: mmH ₂ O]

It was measured by TST 8110 measuring instrument of TST company.

When the flow rate of 32 liters per minute was passed through the area of 100 cm <2> of sample, the difference between the pressure before passing a sample and the pressure after passing a sample was represented by pressure loss.

When the nanofibers are coated on the mat by the electrospinning method, a large amount of nozzles can be arranged even in a narrow space, thereby greatly improving the yield per unit time (coating amount), and the coated nano to the mat axis direction. By easily adjusting the orientation angle of the fiber can be variously adjusted the physical properties of the nanofiber coated mat.

In addition, the present invention can easily produce a hybrid mat coated with two or more kinds of nanofibers having different types or thicknesses of polymers at the same time.

Mat (7) manufactured by the present invention and coated with nanofibers is a daily treatment such as water treatment filter, air cleaning filter, artificial leather, wiping cloth, golf gloves, wig, artificial dialysis filter, artificial blood vessel, adhesion It is useful as a material for a variety of industries, such as inhibitors, artificial bones, flooring materials, and composite material applications.

Claims (25)

Nozzle (2a) in the nozzle block (2) in which the polymer spinning solution in the polymer spinning solution main tank (4) is subjected to a high voltage and is combined in a C shape with one or more unit blocks arranged in the transverse or longitudinal direction. Is applied to the mat 6 by electrospinning on the mat 6 passing through the collector 3, which is a cylindrical conductor rotating in a state in which a high voltage is applied and one side is wrapped by the nozzle block 2. After coating the spun nanofibers, using the transfer roller (8), the manufacturing method of the nanofibers coated mat, characterized in that the nanofibers coated mat (7) wound on the winder (9). The method of producing a nanofiber coated mat according to claim 1, characterized in that it is embossed or dried before winding the nanofiber coated mat (7). The method of making a nanofiber coated mat according to claim 1, characterized in that the mat (6) is one selected from nonwoven fabric, woven fabric, knitted fabric, membrane and braid. 2. Method according to claim 1, characterized in that the mat (6) is fed onto the collector (3) continuously from the feed roller (5). A method according to claim 1, characterized in that the nozzles (2a) in the C-shaped nozzle block (2) are arranged diagonally or in a row in the transverse or longitudinal direction. The method according to claim 1, wherein the nozzle block (2) is composed of one or two or more unit blocks.  The method of manufacturing a nanofiber coated mat according to claim 4, wherein two or more unit blocks are assembled in a C-shaped frame. The method according to claim 1, wherein the nozzle block (2) reciprocates from side to side with respect to the longitudinal direction of the collector (3).  2. Method according to claim 1, characterized in that the nozzle block (2) is located below the collector (3). The method of claim 1, wherein the nozzle is a core-shell structure. The method of claim 1, wherein the polymer spinning solution is polyester resin, nylon resin, polysulfone resin, polylactic acid, chitosan, collagen, cellulose, fibrinogen, sol-gel containing a metal component, copolymers thereof and these Method of producing a nanofiber coated mat, characterized in that consisting of a component selected from the group consisting of a mixture of. The method according to claim 1, wherein the number of nozzles (2) is one or more. The method according to claim 1, wherein the number of nozzles (2) is 100 or more. The method of manufacturing a nanofiber coated mat according to claim 1, wherein the nozzle block (2) and the collector (3) each have a multi-layered form divided into two or more layers by a non-conductive separator. 15. The method of claim 14, wherein the nozzle block (2) and the collector (3) each having a multi-layered form are integral or separate. The method according to claim 14, wherein the heights of the layers constituting each of the nozzle block (2) and the collector (3) having a multi-layered form are different from each other. The method of manufacturing a nanofiber coated mat according to claim 1, wherein at least two nozzle blocks (2) and two or more collectors (3) are used to simultaneously manufacture two or more nanofiber coated mats. The method of manufacturing a nanofiber coated mat according to claim 17, wherein at least two different types of polymer spinning solutions are supplied to each of the two or more nozzle blocks (2). 18. The method of claim 17, wherein the two or more nanofibers coated with the mat are laminated before winding. 18. The method of claim 17, wherein the diameters of each of the two or more nozzle blocks (2) are different from each other. Method according to claim 17, characterized in that the diameters of each of the two or more collectors (3) are different from each other. A nanofiber coated mat characterized in that it is made of the method according to any one of claims 1 to 21 and is composed of nanofibers (2a) coated on the mat (6) and the mat (6). 23. The nanofiber coated mat of claim 22 wherein the nanofibers are hollow or in the form of pores on the surface. 23. The nanofiber coated mat of claim 22 wherein the nanofibers are arranged at an angle of 10 degrees or less in the axial direction of the mat. 23. The nanofiber coated mat of claim 22 wherein the nanofibers are impregnated with a thermoplastic or thermoset resin.

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