KR20100019172A

KR20100019172A - Method of manufacturing nanofiber web

Info

Publication number: KR20100019172A
Application number: KR1020080078063A
Authority: KR
Inventors: 흥 렬 오
Original assignee: 코오롱패션머티리얼 (주)
Priority date: 2008-08-08
Filing date: 2008-08-08
Publication date: 2010-02-18

Abstract

PURPOSE: A manufacturing method of nanofiber web is provided to improve productivity and uniformity of the nanofiber web by effectively preventing a phenomenon an electric filed is produced on polymer liquid. CONSTITUTION: A manufacturing method of nanofiber web includes a step for supplying polymer liquid to a nozzle which is applied with high pressure through a polymer liquid supply pump(2), and a step for electrospinning the polymer liquid towards a collector applied with the high voltage. A nonelectrical polymer liquid supply pump is used as the polymer liquid supply pump. The nonelectrical polymer liquid supply pump comprises a plurality of roller adjusting the amount of the polymer liquid.

Description

Method of manufacturing nanofiber web {Method of manufacturing nanofiber web}

The present invention relates to a method for manufacturing a nanofiber web using an electrospinning method, and more particularly, to the use of a non-electromagnetic polymer solution supply pump during electrospinning, to a nanofiber web which greatly improves the uniformity and productivity of the nanofiber web. It relates to a manufacturing method.

Electrospinning was first introduced in Germany in the 1930s as a relatively simple way to produce ultrafine fibers (hereinafter referred to as "nano fibers") with diameters of tens to hundreds of nm. However, the technology of the time was limited to commercialization of this technology, so it was not received attention, and research began again until the 1970s, and full-scale research began only after the 2000s.

Electrospinning applied a high voltage of several thousand to tens of thousands of volts to the polymer solution, and the force of the tangential vector exceeding the surface tension of the solvent was applied from the polymer solution to form a fine polymer jet from the polymer solution. The band advances rapidly toward the object. The jet of polymer jet is then dispersed and scattered back into a number of fine fibers, the diameter of the fine fibers have a thickness of several tens to hundreds of nanometers.

Electrospinning can be used to produce nanofiber webs as shown in Figure 3 consisting of nanofibers having a thickness of several tens to hundreds of nanometers from a polymer solution, using them for high functional clothing, ultra-precision filters, cell culture materials (scaffold). High performance products, such as) can be obtained.

3 is an electron micrograph of a nanofiber web.

In order to commercially manufacture a nanofiber web, Korean Patent No. 0412241, Korean Patent No. 0422459 and Korean Patent Application No. 2005-15610 propose a method of electrospinning a plurality of nozzles through a plurality of nozzles.

Specifically, according to the conventional method, as shown in FIG. 1, the polymer solution is supplied to the plurality of nozzles 3 under high voltage through the electric polymer solution supply pump 2, and then charged to the nozzles. Was electrospun onto a fiber substrate positioned on the collector 4 subjected to high voltage to produce a nanofiber web.

1 is a schematic diagram of a general electrospinning process.

In the conventional method, since the polymer solution stored in the polymer solution main tank 1 is supplied to the nozzle 3 through the electric supply pump 2, the nozzle is supplied to the nozzle by electricity loaded on the electric supply pump 2. There was a problem that the electric field is caught in the polymer solution to be supplied is difficult to uniform electrospinning.

This reduces the uniformity and productivity of the conventional nanofiber web.

An object of the present invention is to significantly improve the uniformity and productivity of nanofiber webs by solving such conventional problems.

Still another object of the present invention is to effectively prevent the phenomenon of making the electrospinning difficult due to the electric field in the polymer solution due to the polymer solution supply pump in manufacturing the nanofiber web.

The method of manufacturing a nanofiber web according to the present invention for achieving the above object, the polymer solution is supplied to the nozzle (3) after supplying a high voltage to the nozzle (3) through the polymer solution supply pump (2) When the polymer solution is electrospun toward the collector 4, which is subjected to a high voltage having a charge opposite to that of the nozzle 3, when the nanofiber web is manufactured, the supply pipe of the polymer solution is supplied by the air pressure supplied from the air supply device 7 It is characterized in that to use a non-electric feed pump consisting of rollers to squeeze (8) to adjust the amount of the polymer solution supplied to the nozzle (3).

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

First, the present invention supplies the polymer solution stored in the polymer solution main tank 1 as shown in FIG. 1 to the nozzle 3 under high voltage through the non-electromagnetic polymer solution supply pump 2.

Next, the polymer spinning solution supplied to the nozzle 3 is electrospun toward the collector 4 subjected to a high voltage with a different charge from the nozzle to volatilize the nanofibers, and then the volatilized nanofibers are volatilized to the collector 4. ) To produce a nanofiber web.

1 is a schematic diagram of a general electrospinning process.

Each of the nozzle 3 and the collector 4 is subjected to a high voltage with a different charge for electrospinning.

The polymer solution in the nozzle 3 has a higher stress in the normal vector direction than the surface tension of the polymer solution due to the high voltage applied to the nozzle 3 and the collector 4 to form a polymer jet.

The polymer jet is directed toward the collector 4 with the opposite charge, and maintains a jet state from the nozzle 3 to a predetermined period, after which it is volatilized into nanofibers and accumulated on the collector 4. .

The non-electromagnetic polymer solution supply pump (hereinafter, abbreviated as " non-electric supply pump ") used in the present invention is a supply pipe of the polymer solution by the air pressure supplied from the air supply device 7, as shown in FIG. It consists of rollers squeezing (8) to adjust the amount of supply of the polymer solution supplied to the nozzle (3).

2 is a schematic diagram of a non-electromagnetic polymer solution supply pump 2 used in the present invention.

The non-electric feed pump (2) to the nozzle (3) by squeezing (sqeezing) the supply pipe (8) of the polymer solution with the air pressure supplied from the external air supply device (7) instead of using electricity Since a certain amount of the polymer solution is supplied, the conventional problem of generating an electric field in the polymer solution is effectively prevented.

As a result, the present invention can uniformly and continuously electrospin nanofibers to improve the uniformity and productivity of the nanofiber web produced.

The polymer solution may be polyamide resin, polyurethane resin, polyester resin, polystyrene resin, cellulose, polyvinylacetate, polyvinylchloride, polyvinyl alcohol resin, polysulfone resin, polyacrylonitrile resin, polymethylmethacrylate resin All soluble fiber-forming polymers such as polystyrene resin, polyacrylic acid resin, polyolefin resin, wholly aromatic polyamide resin or polyvinylidene fluoride resin can be used.

Moreover, there is no restriction | limiting also in the kind of solvent for melt | dissolving a high molecular substance. The solvent is limited depending on the polymer, and the solvent can be freely determined depending on the polymer used to prepare the nanofiber web. Moreover, there is no restriction also about the manufacturing method of a polymer solution.

The concentration of the polymer solution can range from as low as 1% or less to as high as 50% or less.

In addition, two or more kinds of polymers may be used simultaneously. It is also possible to dissolve two or more different polymers in a solvent, and to dissolve and use polymers having different characteristics such as molecular weight in a solvent.

On the collector 4, a fibrous base or film may be located.

The collector 4 is located on the horizontal, lower, upper surface, etc. of the nozzle 3, and moves at a constant linear velocity.

The surfaces of the nozzle 3 and the collector 4 are gold, silver, tungsten, copper, stainless steel, alloys thereof, and the like, and more preferably, platinum is coated on stainless steel.

The present invention can effectively prevent a phenomenon in which an electric field is generated due to the supply pump in the polymer solution subjected to high voltage because the non-electromagnetic polymer solution supply pump is used instead of the conventional electric polymer solution supply pump.

Therefore, the present invention has the effect of greatly improving the uniformity and productivity of the nanofiber web produced by uniformly made the electrospinning.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. However, the present invention is not limited only to the following examples.

Example One

Polyamide was dissolved in formic acid at a concentration of 8% to prepare a polyamide solution at 25 ° C. and used as a polymer solution.

According to the process shown in FIG. 1, the polyamide solution stored in the polymer solution main tank 1 is supplied to the plurality of nozzles 3 in which the high voltage of the anode is applied through the non-electric supply pump 2 shown in FIG. 2. Next, this was sprayed toward the collector 4 of the metal plate on which the high voltage of the cathode was applied to volatilize the nanofibers, and then the volatilized nanofibers were laminated on the collector to prepare a nanofiber web.

At this time, a voltage of 55,000 volts was applied to the plurality of nozzles 3 and the collector 4 by using a voltage generator 6 connected with an AC power source of 220 volts and 60 Hz, and the nozzle discharge amount was 0.5 ml / min.

In addition, the space | interval of the nozzle 3 and the collector 4 was set to 30 cm.

The results of evaluating various physical properties of the prepared nanofiber webs are shown in Table 2.

Example 2- Example 6

The nanofiber web was subjected to the same conditions as in Example 1 except that the polymer and solvent constituting the polymer solution, the voltage applied to the collector and the nozzles, the discharge amount of the nozzle, and the distance between the nozzle and the collector were changed as shown in Table 1. Prepared.

Manufacturing conditions of Example 1 to Example 6 division Feed Pump (2) Polymer type menstruum Voltage (volts) Nozzle Discharge Rate (ml / min) Nozzle-collector spacing (cm) Example 1 Non-electric supply pump of Figure 3 Polyamide Formic acid 55,000 0.5 30 Example 2 Non-electric supply pump of Figure 3 Polyurethane Dimethylformamide 35,000 0.6 30 Example 3 Non-electric supply pump of Figure 3 Polyamide Formic acid 70,000 0.7 45 Example 4 Non-electric supply pump of Figure 3 Polyurethane Dimethylformamide 50,000 0.8 45 Example 5 Non-electric supply pump of Figure 3 Polypropylene toluene 40,000 0.5 30 Example 6 Non-electric supply pump of Figure 3 Polypropylene toluene 60,000 0.8 45

Comparative Example One

A nanofiber web was prepared in the same manner as in Example 1 except that the electric feed pump was used as the polymer solution feed pump (2).

Comparative Example 2

A nanofiber web was prepared in the same manner as in Example 2 except that the electric feed pump was used as the polymer solution feed pump (2).

Comparative Example 3

A nanofiber web was prepared in the same manner as in Example 3 except that the electric feed pump was used as the polymer solution supply pump (2).

Comparative Example 4

A nanofiber web was prepared in the same manner as in Example 4 except that the electric feed pump was used as the polymer solution feed pump (2).

Comparative Example 5

A nanofiber web was prepared in the same manner as in Example 5 except that the electric feed pump was used as the polymer solution supply pump 2.

Comparative Example 6

A nanofiber web was prepared in the same manner as in Example 6 except that the electric supply pump was used as the polymer solution supply pump 2.

Property evaluation result division Moisture permeability average (g / ㎡ / day) Water vapor permeability standard deviation (g / ㎡ / day) Defects (dog) Example 1 14,000 250 0 Example 2 15,000 300 0 Example 3 17,000 320 0 Example 4 16,000 300 0 Example 5 14,000 260 0 Example 6 17,000 280 0 Comparative Example 1 18,000 2,500 11 Comparative Example 2 18,000 1,800 12 Comparative Example 3 15,000 1,900 6 Comparative Example 4 18,000 1,500 10 Comparative Example 5 19,000 2,200 12 Comparative Example 6 20,000 2,000 9

As can be seen from the above evaluation results, the standard deviation of the water vapor transmission rate of the nanofiber webs prepared in Examples 1 to 6 is very uniform, not more than 500 g / m 2 / day. In addition, a very good quality nanofiber web without defects on the nanofiber web was obtained.

However, the nanofiber webs prepared in Comparative Examples 1 to 6 exhibited almost the same moisture permeability as Examples 1 to 6, but showed a very high standard deviation of 2,000 g / m 2 / day or more. In addition, there are also many defects compared to the nanofiber web prepared in Examples 1 to 6 at the level of 6 to 12. The defects are mostly polymer solutions away from the nozzles, and the clogging of nozzles has also been affected by varieties.

Properties of Table 2 were evaluated by the following method.

Of nanofiber web Breathable

The water vapor permeability of the nanofiber web was evaluated 10 times with different measurement sites, and the average value and standard deviation were calculated. The method of evaluating moisture permeability is to evaluate the number of grams of moisture passed after 24 hours of application of moisture to a fabric under a certain pressure, according to Korean Industrial Standard KS K 0594.

Drawbacks of Nanofiber Web

The number of defects within 45 cm wide and 5 m long for the nanofiber web is visually determined. The defects were evaluated by the number of points where the polymer solution fell and the number of points where no nanofibers were applied.

1 is a schematic diagram of an electrospinning process.

2 is a schematic diagram of a polymer solution supply pump 2 used in the present invention.

3 is an electron micrograph of the nanofiber web.

* Description of the main parts of the drawings

1: Polymer solution main tank 2: Polymer solution supply pump

3: nozzle 4: collector

5: voltage transfer rod 6: voltage generator

7: air supply device 8: supply pipe of polymer solution

3: nozzle block 5: voltage transfer rod.

Claims

After supplying the polymer solution through the polymer solution supply pump (2) to the nozzle (3) under high voltage, the collector (4) with the high voltage under the opposite charge to the nozzle (3) is supplied to the polymer solution supplied to the nozzle (3). In manufacturing the nanofiber web by electrospinning toward the), by squeezing the supply pipe (8) of the polymer solution by the air pressure supplied from the air supply device (7) as the polymer solution supply pump (2) Method for producing a nanofiber web, characterized in that using a non-electric feed pump consisting of rollers for adjusting the supply amount of the polymer solution supplied to the nozzle (3).

The method of claim 1, wherein the polymer solution is polyamide resin, polyurethane resin, polyester resin, polystyrene resin, cellulose, polyvinylacetate, polyvinyl chloride, polyvinyl alcohol resin, polysulfone resin, polyacrylonitrile resin, poly A method for producing a nanofiber web, characterized in that it is one selected from the group consisting of methyl methacrylate resin, polystyrene resin, polyacrylic acid resin, polyolefin resin, wholly aromatic polyamide resin, and polyvinylidene fluoride resin.

A method according to claim 1, characterized in that the collector (4) moves at a constant linear velocity.

The method of claim 1, wherein the nozzle (3) and the collector (4) surface is made of a nanofiber web, characterized in that made of one material selected from gold, silver, tungsten, copper, stainless steel and alloys thereof. Way.

The method of manufacturing a nanofiber web according to claim 1, wherein a fibrous base or a film is placed on the collector (4).