KR20100047993A - Nanofiber web with network structure and method of manufacturing the same - Google Patents

Abstract

PURPOSE: A nanofiber network structure and a manufacturing method thereof are provided to connect high-denier nanofibers to low-denier nanofiber which is branched from the high-denier nanofbier surface by adding dissociatable inorganic materials in a macromolecular solution. CONSTITUTION: A nanofiber network structure comprises high-denier nanofibers(a) of which diameter is 55-2,000 nm and low-denier nanofibers(b) of which diameter is 0.1-50 nm. The nanofiber network structure is manufactured by an electric spinning method. The low-density nanofibers are branched from the high-density nanofiber surface. The low-density nanofibers connect gaps between the high-density nanofiber.

Description

Nanofiber web with network structure and method of manufacturing the same

The present invention relates to a nanofiber network structure having a network structure and useful as a carrier in the medical field, and a method of manufacturing the same, more specifically, produced by electrospinning method consisting of a single polymer and relatively large diameter between nanofibers The present invention relates to a nanofiber web having a structure in which relatively thin nanofibers are connected in a network structure (hereinafter referred to as a "network structure"), and a method of manufacturing the same.

In the present invention, the nanofiber network structure is defined as a nanofiber web having the network structure.

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, in the conventional method, as shown in FIG. 15, the polymer solution is supplied to the plurality of nozzles 3 under high voltage through the metering pump 2, and then a high voltage having a charge opposite to the nozzle is applied. Nanofiber web was prepared by electrospinning on a fiber substrate placed on the hanging collector (4).

15 is a process schematic diagram showing an example of a conventional electrospinning process.

However, in the case of electrospinning a single polymer by the conventional electrospinning method, only nanofiber webs in which nanofibers having the same diameter are irregularly laminated with each other are manufactured, and (ⅰ) diameters made of the same polymer are relatively Coarse nanofibers and (ii) are composed of nanofibers that are branched from a relatively coarse nanofiber surface and are relatively thin in diameter, connecting relatively coarse nanofibers between the coarse nanofibers. It was impossible to manufacture a nanofiber web having a network structure.

On the other hand, by electrospinning the polymer solution first by the conventional electrospinning method to produce a nanofiber web consisting of nanofibers having a relatively large diameter to the level of 55nm or more, and then on the prepared nanofiber web Even when the same type of polymer solution is electrospinned by the conventional electrospinning method and the nanofibers having relatively narrow diameters are laminated to the level of 50 nm or less, two kinds of nanofibers having different diameters can be stacked in the nanofiber web. Although it is possible, nanofiber webs having a network structure in which nanofibers branched from the coarse nanofiber surface and relatively thin in diameter are connected between nanofibers having relatively large diameters could not be manufactured.

That is, the nanofiber web manufactured by the second electrospinning process is not a network structure in which nanofibers branched from the thick nanofiber surface and relatively thin in diameter connect between nanofibers having a relatively large diameter. Relatively thick nanofibers on top of relatively thick nanofibers are simply stacked structures.

According to the present invention, even when a single polymer spinning solution is electrospun through nozzles of the same size, the nanofibers having a relatively large diameter and branched from the coarse nanofiber surface are formed at the same time, thereby forming a relatively thin nanofiber. The relatively narrow nanofibers are to provide a nanofiber network structure having a network (Network) structure that connects between relatively thick nanofibers and a method of manufacturing the same.

In the present invention, in order to manufacture a nanofiber network (Network) structure, a small amount of dissociable inorganic material in the electrospun polymer solution is added and then electrospun.

Specifically, when the electrospinning, the ions dissociated in the polymer solution are applied to each other and the pulling force is applied to each other. Thus, the nanofibers having a relatively larger diameter of the electrospun than the electrospun polymer material (hereinafter, referred to as "Taeseomdo") Nanofibers ": nanofibers having a relatively small diameter from the surface of a) of FIG. 1 (hereinafter referred to as" fine-fiber nanofibers ": dissociated cations and anions are bonded to each other after branching) Branched nanofibers are connected to each other by the force to produce a nanofiber network structure according to the present invention.

The nanofiber network structure of the present invention has a unique network structure and is useful as a carrier material, a drug and gene carrier, a wound treatment material, a filter material, a secondary battery material, a sensor material, a catalyst material, and the like in the pharmaceutical field.

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

First, the nanofibrous network structure according to the present invention is manufactured by (i) electrospinning method as shown in FIGS. 1 to 11, and the diameter of the nanofibers (a) having a diameter of 55 nm to 2,000 nm. , (Ii) is made of an electrospinning method and composed of fine fineness nanofibers (b) having a diameter of 0.1 to 50 nm, and the fine fineness nanofibers (b) are branched from the surface of the fine fineness nanofibers (a). And the Taeseomdo nanofibers (a) are connected to each other in a network structure, and the diameter of the Taeseomdo nanofibers (a) is three times greater than or equal to the diameter of the Sedodo nanofibers (b). The fineness nanofibers (a) and the fineness nanofibers (b) are characterized in that they are composed of the same type of polymer resin.

More specifically, the nanofiber network structure according to the present invention has a network structure in which the fine-grained nanofibers (b) connect between the fine-grained nanofibers (a) as a nano-islet web. Have

The fine-grained nanofibers (b) are formed by a mechanism in which nanofibers branched from the surface of the fine-grained nanofibers (a) during electrospinning are connected to each other by ionic bonding force.

The diameter of the micro fineness nanofibers (a) is 50 nm or more, preferably 55 to 2,000 nm, and the diameter of the fine fineness nanofibers (b) is 50 nm or less, more preferably 0.1 to 30 nm. The diameter of the Taeseomdo nanofibers (a) is three times or more than the diameter of the Seomdo nanofibers (b).

The Taeseomdo nanofibers (a) and Seseodo nanofibers (b) are composed of the same type of polymer resin.

Next, a method for producing a nanofiber network structure according to the present invention will be described in detail.

Method for producing a nanofiber network structure according to the present invention is characterized in that in the preparation of the nanofibrous structure by electrospinning the polymer solution, the inorganic material capable of dissociation in the polymer solution is added to the polymer solution.

The amount of the inorganic substance that can be dissociated in the polymer solution is appropriately adjusted according to the type of the inorganic substance. For example, when the inorganic material is NaCl, less than 20 parts by weight, more preferably 1 to 19.9 parts by weight, relative to 100 parts by weight of the polymer solids of the polymer solution, and when the inorganic CaCl ₂ or KBr, the polymer solids of the polymer solution 100 It is preferable to add 20 weight part or less with respect to a weight part, More preferably, 1-20 weight part.

When the addition amount of the said inorganic substance exceeds the said range, electrospinning property worsens and it may generate | occur | produce beads (drops), and it is unpreferable.

The inorganic material that can be dissociated in the polymer solution is one or a mixture thereof selected from (i) a compound consisting of an alkali metal and a halogen element, and (ii) a compound consisting of an alkaline earth metal and a halogen element.

The alkali metal is one selected from Li, Na, K, Rb, Cs, and Fr, the alkaline earth metal is one selected from Be, Mg, Ca, Sr, Ba, and Ra, and the halogen elements are F, Cl, Br, It is one selected from I, At and Uus.

Specific examples of the inorganic material that can be dissociated in the polymer solution are CaCl ₂ , NaCl, KBr or a mixture thereof. That is, a mixture of CaCl ₂ / NaCl, a mixture of CaCl ₂ / KBr or a mixture of NaCl / KBr, a mixture of CaCl ₂ / NaCl / KBr can be used as an inorganic material capable of dissociation in the polymer solution.

Dissociated cations and anions are present in the polymer solution by the inorganic material added in the electrospun polymer solution.

When the polymer solution is electrospun, as shown in FIG. 1, the Taeseomdo nanofibers (a) are formed, and at the same time, the surface of the Taeseodo nanofibers (a) is attracted by attraction and repulsion between ions dissociated in the polymer solution. After the fine fine nanofiber strands are branched from, the branched fine fine nanofiber strands are connected to each other by a force of a cation and an anion to form fine fine nanofibers (b).

1 is a schematic diagram of a nylon nanofiber network structure of the present invention prepared in Example 1.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.

Example 1

A polymer solution was prepared by dissolving nylon 6 resin at a concentration of 20% by weight in a solution of formic acid and acetic acid mixed at an 8: 1 ratio, and then 5 parts by weight of NaCl was added to 100 parts by weight of the polymer solids of the polymer solution. It was added inside to prepare an electrospinning liquid.

Subsequently, the prepared electrospinning solution was electrospun through the spinning nozzles having the same diameter in the conventional electrospinning process shown in FIG. 15 to prepare a nanofiber web.

An electron micrograph of the prepared nanofiber web was as in FIG. 2, and an electron micrograph of an enlarged network structure in FIG. 2 was shown in FIG. 3.

Examples 2 to 6 and Comparative Example 1

The electrospinning solution was electrospun in the same manner as in Example 1 except that the type and amount of the inorganic substance added in the polymer solution (based on 100 parts by weight of the polymer solids in the polymer solution) were changed as shown in Table 1 Nanofiber webs (structures) were prepared.

Electron micrographs and enlarged electron micrographs of the network structure of the prepared nanofiber web are shown in Table 2.

Manufacture conditions division Inorganic salt type Inorganic salt content (parts by weight) Example 1 NaCl 5 Example 2 NaCl 15 Example 3 CaCl ₂ 15 Example 4 CaCl ₂ 5 Example 5 KBr 15 Example 6 KBr 5 Comparative Example 1 NaCl 21

Electron micrograph division Electron micrograph of manufactured nanofiber web Electron microscopy image of enlarged network or bead structure of the manufactured nanofiber web Example 1 2 3 Example 2 4 - Example 3 5 6 Example 4 7 - Example 5 8 9 Example 6 10 11 Comparative Example 1 Figure 12 13 and 14

The nanofiber webs prepared in Examples 1 to 6 had a network structure, but the nanofiber webs prepared in Comparative Example 1 had a structure in which beads (drops) were formed instead of the network structure. .

1 is a schematic diagram of a nylon nanofiber network structure prepared in Example 1.

Figure 2 is an electron micrograph of the nylon nanofiber network structure prepared in Example 1.

3 is an enlarged electron microscope photograph of a network structure part of FIG. 2;

Figure 4 is an electron micrograph of the nylon nanofiber network structure prepared in Example 2.

Figure 5 is an electron micrograph of the nylon nanofiber network structure prepared in Example 3.

FIG. 6 is an enlarged electron microscope photograph of a network structure portion of FIG. 5; FIG.

7 is an electron micrograph of the nylon nanofiber network structure prepared in Example 4.

8 is an electron micrograph of the nylon nanofiber network structure prepared in Example 5.

FIG. 9 is an enlarged electron microscope photograph of a network structure part of FIG. 8; FIG.

10 is an electron micrograph of the nylon nanofiber network structure prepared in Example 6.

FIG. 11 is an enlarged electron microscope photograph of a network structure portion of FIG. 10. FIG.

12 is an electron micrograph of the nylon nanofiber structure prepared in Comparative Example 1.

FIG. 13 is an enlarged electron micrograph of a bead part in FIG. 12. FIG.

14 is an enlarged electron micrograph of the surface of beads (spheres) in FIG. 13.

15 is a process schematic diagram showing an example of an electrospinning process.

* Explanation of symbols on the main parts of the drawings

a: Taesumdo nanofiber b: Sesumido nanofiber

1: Electrospinning solution supply tank 2: Metering pump

3: nozzle 4: collector

5: voltage transfer rod 6: voltage generator

Claims (8)

(Iii) Taisando nanofibers (a) having a diameter of 55 nm to 2,000 nm by electrospinning, and (ii) Sesido nanofibers (b) having a diameter of 0.1 to 50 nm by electrospinning. The fine-grained nanofibers (b) are branched from the surface of the fine-grained nanofibers (a) to connect between the fine-grained nanofibers (a) in a network structure. The diameter of the fineness nanofibers (a) is three times or more than the diameter of the fineness nanofibers (b), and the finest nanofibers (a) and the fineness nanofibers (b) are composed of the same type of polymer resin. Nanofiber network structure, characterized in that. The nanofiber network structure according to claim 1, wherein the fineness nanofibers (b) have a diameter of 0.1 to 30 nm. In preparing a nanofibrous structure by electrospinning a polymer solution, a method of manufacturing a nanofiber network structure comprising adding an inorganic material capable of dissociation in the polymer solution into the polymer solution. 4. The inorganic material capable of dissociating in a polymer solution is one or a mixture of (i) a compound consisting of an alkali metal and a halogen element, and (ii) a compound consisting of an alkaline earth metal and a halogen element. Method of manufacturing a nanofiber network structure. The method of claim 4, wherein the alkali metal is one selected from Li, Na, K, Rb, Cs, and Fr. The method of claim 4, wherein the alkaline earth metal is one selected from Be, Mg, Ca, Sr, Ba, and Ra. The method of claim 4, wherein the halogen element is one selected from F, Cl, Br, I, At, and Uus. 4. The method of claim 3, wherein the inorganic material capable of dissociation in the polymer solution is one selected from CaCl ₂ , NaCl, KBr, and mixtures thereof.

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