KR101111223B1 - Biodegradable oxide cellose nonwoven fabric consisting of the nano fiber and preparing thereof - Google Patents

Abstract

The present invention relates to a cellulose oxide nonwoven fabric, and more particularly, to a method for producing a biodegradable cellulose oxide nonwoven fabric, in which an aqueous solution is prepared by adding distilled water and ethanol to acetone, and then 10 to 30 wt% of cellulose acetate is added to the aqueous solution. Dissolving; Preparing a non-woven fabric by electrospinning the solution in which the cellulose acetate is dissolved and then deacetylating the solution; Oxidizing the nano-nonwoven fabric to an N ₂ O ₄ solution; Neutralizing the N ₂ O ₄ solution using sodium hydroxide solution; And it relates to a biodegradable cellulose nonwoven fabric consisting of nanofibers comprising the step of washing the neutralized nonwoven fabric in a mixed solution of isopropyl alcohol and water and dried in air.

Cellulose acetate, electrospun, cellulose oxide, nonwoven

Description

Biodegradable oxide cellose nonwoven fabric consisting of the nano fiber and preparing etc.

The present invention relates to a cellulose oxide nonwoven fabric and a method for producing the same, and more particularly, to a biodegradable cellulose oxide nonwoven fabric composed of nanofibers from cellulose acetate and a method for producing the same.

Cellulose is one of the most abundant biological resources on the planet, and is an infinite resource that repeats the cycle of production, decomposition, use and production by the laws of nature. It has been provided to humankind as a functional, low-cost renewable material for thousands of years. Such cellulose has been actively developed in order to utilize the cellulose component of plants as a resource of energy, food, etc. Recently, as the need for environmentally friendly polymer materials increases, cellulose is used in various functional polymer materials and industrial fields. There is an active research to replace the polymer resources.

The third hydroxyl group of the cellulose molecule can react with both monovalent and dihydric alcohol groups to undergo chemical reactions such as esterification, nitriding, etherification, and oxidation, and as a biocompatible substance, various biochemical materials can be used for various biomedical applications. Can be converted to a range. Double oxidized cellulose is a product of Johnson & Johnson's Interceed, which is used as an anti-adhesion agent, and is a knitted product. It has good adhesion to severe bent organs and tissues, but because of the large pore size, various cells and blood Since permeation of proteins and the like can easily occur, there is a problem of low efficiency as a separation membrane.

On the other hand, nanofiber nonwoven fabrics using electrospinning have good flexibility and high efficiency compared to ordinary materials of the same thickness and small pore size, resulting in high efficiency as a separator.

A typical example of the method of directly spinning the cellulose is a method of spinning using NMMO (4-methylmorpholine N-oxide), but the method is difficult to make nano-sized fibers, even if the nano-sized at 80 ℃ or less Non-woven fabrics are difficult to laminate due to the solidified NMMO solution properties.

In order to compensate for these disadvantages, Korean Patent Laid-Open Publication No. 2008-0075627 discloses a method for producing cellulose nanofibers by electrospinning cellulose acetate and deacetylating it with a mixed solution of potassium hydroxide and ethanol. However, the patent did not mention the nonwoven fabric utilized as a hemostatic agent, an anti-adhesion agent, etc. which has excellent biodegradability as cellulose oxide.

Therefore, it is desired to manufacture an cellulose oxide nonwoven fabric composed of nanofibers, which serves as a separator in which permeation of various cells, blood proteins, etc. cannot easily occur, and is applicable to medical applications such as hemostatic agents and anti-adhesion agents having excellent biodegradability.

In order to solve the above problems, an object of the present invention is to prepare a biodegradable cellulose nonwoven fabric composed of nanofibers, which serves as a separator in which cells and blood proteins are not easily permeated when used for medical purposes.

In addition, an object of the present invention is to produce an cellulose oxide nonwoven fabric composed of nanofibers for medical applications such as hemostatic agents and anti-adhesion agents.

In order to achieve the above object, the present invention provides a method for producing a biodegradable cellulose nonwoven fabric, the step of dissolving 10 to 30% by weight of cellulose acetate in the aqueous solution after preparing an aqueous solution by adding distilled water and ethanol to acetone. ; Preparing a non-woven fabric by electrospinning the solution in which the cellulose acetate is dissolved and then deacetylating the solution; Oxidizing the nano-nonwoven fabric to an N ₂ O ₄ solution; Neutralizing the N ₂ O ₄ solution using sodium hydroxide solution; And washing the neutralized nonwoven fabric with a mixed solution of isopropyl alcohol and water and drying the same in air.

In another aspect, the present invention provides a method for producing a biodegradable oxidized cellulose nonwoven fabric consisting of nanofibers, characterized in that spinning at a voltage of 10 to 40KV and a spinning distance of 5 to 20cm during the electrospinning.

In another aspect, the present invention provides a method for producing a biodegradable cellulose oxide nonwoven fabric consisting of nanofibers, characterized in that the temperature of oxidizing the nano nonwoven fabric to N ₂ O ₄ solution is 25 to 35 ℃.

In another aspect, the present invention provides a method for producing a biodegradable cellulose oxide nonwoven fabric consisting of nanofibers, characterized in that the time to oxidize the nano nonwoven fabric to N ₂ O ₄ solution is 5 to 20 hours.

In addition, the present invention is the ratio of isopropyl alcohol and water when the neutralized nonwoven fabric is washed with a mixed solution of isopropyl alcohol and water is 40: 50 to 60: 40 by volume ratio of biodegradable oxidized cellulose consisting of nanofibers Provided is a method for producing a nonwoven fabric.

In addition, the present invention, in the biodegradable cellulose oxide nonwoven fabric, N ₂ O ₄ is a nano-non-woven fabric that is deacetylated after electrospinning by dissolving 10-30% by weight of cellulose acetate in an aqueous solution prepared by adding distilled water and ethanol to acetone It provides a biodegradable cellulose oxide nonwoven fabric consisting of nanofibers prepared by oxidation reaction to a solution.

In another aspect, the present invention provides a biodegradable oxidized cellulose nonwoven fabric consisting of nanofibers, characterized in that spinning at a voltage of 10 to 40KV and a spinning distance of 5 to 20cm during the electrospinning.

In another aspect, the present invention provides a biodegradable cellulose oxide nonwoven fabric consisting of nanofibers, characterized in that the temperature of oxidizing the nano nonwoven fabric to N ₂ O ₄ solution is 25 to 35 ℃.

In another aspect, the present invention provides a biodegradable cellulose oxide nonwoven fabric consisting of nanofibers, characterized in that the time for the oxidation reaction of the nano nonwoven fabric to the N ₂ O ₄ solution is 5 to 20 hours.

Biodegradable cellulose oxide nonwoven fabric composed of nanofibers according to the present invention and a method for producing the same have an effect of acting as a separation membrane that does not easily penetrate cells and blood proteins when used for medical purposes.

In addition, the biodegradable cellulose oxide nonwoven fabric composed of nanofibers according to the present invention and a manufacturing method thereof may be applied to medical fields such as hemostatic agents and anti-adhesion agents.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, it should be noted that, in the drawings, the same components or parts have the same reference numerals as much as possible. In describing the present invention, detailed descriptions of related well-known functions or configurations are omitted in order not to obscure the subject matter of the present invention.

The terms " about ", " substantially ", etc. used to the extent that they are used herein are intended to be taken to mean an approximation to or in the numerical value of the manufacturing and material tolerances inherent in the meanings mentioned, Accurate or absolute numbers are used to help prevent unauthorized exploitation by unauthorized intruders of the referenced disclosure.

The present invention is characterized in that the cellulose nonwoven fabric prepared in nano size is made of oxidized cellulose nonwoven fabric using N ₂ O ₄ solution.

In the method for producing a biodegradable cellulose oxide nonwoven fabric according to an embodiment of the present invention, by adding distilled water and ethanol to acetone to prepare an aqueous solution, dissolving 10 to 30% by weight of cellulose acetate in the aqueous solution; Preparing a non-woven fabric by electrospinning the solution in which the cellulose acetate is dissolved and then deacetylating the solution; Oxidizing the nano-nonwoven fabric to an N ₂ O ₄ solution; Neutralizing the N ₂ O ₄ solution using sodium hydroxide solution; And washing the neutralized nonwoven fabric with a mixed solution of isopropyl alcohol and water and drying the same in air.

To prepare an aqueous solution by adding distilled water and ethanol to the acetone in the step of dissolving 10 to 30% by weight of cellulose acetate in the aqueous solution to add distilled water for dilution in acetone and to make the electrospinning made in the next step In order to add ethanol, it is preferable to add 1 to 30 parts by weight of distilled water and 1 to 20 parts by weight of ethanol based on 100 parts by weight of the aqueous solution. The aqueous solution mixed within the above range is well spinning during proper dilution and electrospinning. 10 to 30% by weight of cellulose acetate is dissolved in the aqueous solution to prepare an electrospinning solution.

In the step of preparing a non-woven fabric by electrospinning the solution in which the cellulose acetate is dissolved, followed by deacetylation, the electrospinning value that can be generally used as the electrospinning is not particularly limited, and the diameter of the nanofibers, the thickness of the nanofibers, etc. In consideration of this, it can be appropriately selected, and an electrospinning apparatus capable of applying a high voltage generally used can be used.

When the electrospinning using the electrospinning device to emit at a voltage of 10 to 40KV and a spinning distance of 5 to 20cm, nanofiber nonwoven fabric of 100 to 400nm can be prepared. Radiation is well performed in the voltage range of the above range, and if the voltage is less than 10KV, fiber formation is not performed, and if it exceeds 40KV, there is a problem that device damage due to discharge occurs. In addition, the nonwoven fabric formed of nanofibers is not formed at the spinning distance of less than the above range, and the concentration is not good at the spinning distance of the above range. Next, to deacetylate the electrospun nonwoven fabric, as a non-limiting example, deacetylated with a solution of potassium hydroxide and ethanol for 2 to 4 hours.

In the step of oxidizing the nano nonwoven fabric to the N ₂ O ₄ solution, the prepared nano cellulose nonwoven fabric is oxidized using N ₂ O ₄ . Cellulose can be oxidized using metaperiodate, hypochlorite, dichromate, and the like.However, a method for producing an oxidized cellulose having high carboxyl content and excellent physical properties can be oxidized using N ₂ O ₄ . Is the most stable way.

There are two methods of oxidizing using the N ₂ O ₄ , gas phase oxidation and liquid phase oxidation. In the present invention, the liquid phase oxidation method is used, and there is an advantage in that an cellulose oxide having a relatively high and uniform carboxyl content can be prepared compared to the gas phase.

When the cellulose is oxidized by the liquid phase oxidation method, the N ₂ O ₄ solution is physically and chemically absorbed into the cellulose, is initially rapidly absorbed into the amorphous region, and is gradually absorbed into the crystalline region with time. The oxidation reaction to the N ₂ O ₄ solution is the hydroxyl group of the 6th C of cellulose is substituted with a carboxyl group.

The carboxyl group substituted as in Scheme 1 promotes absorption of water by swelling the cellulose structure while changing into an acidic water-soluble salt as water is absorbed. Once decomposition begins, degradation continues along the polymer chain, with the decomposition forming new carbonyl groups.

On the other hand, the oxidation reaction through the N ₂ O ₄ The content of the cellulose oxide changes with temperature and time, the reaction temperature is suitable 25 to 35 ℃ temperature. The higher the reaction temperature, the more the carboxyl content is substituted at the same time, but if the reaction temperature exceeds 35 ° C, the nonwoven fabric becomes too stiff and loses the softness of the nanofibers, and the reaction temperature is less than 25 ° C. In the case of the carboxyl-substituted content is low, it does not absorb moisture well.

In addition, the oxidation reaction time is suitable for 5 to 20 hours, because it affects the change in the carboxyl content and the decomposition behavior of the cellulose oxide. With a reaction time of less than 5 hours, oxidized cellulose nonwovens hardly biodegrade.

1 shows the results of observing the change of the cellulose nano nonwoven fabric according to the oxidation reaction time with Fourier Transform-Inforared Spectroscope (FT-IR), and FIG. 2 shows the change of carboxyl content according to the oxidation reaction time and temperature change. It is shown. In addition, Figure 3 shows the change in weight loss with the immersion time of the cellulose oxide nonwoven fabric for each oxidation reaction time. As a result, the longer the oxidation reaction time, the greater the weight loss according to the immersion time.

Next, to neutralize the N ₂ O ₄ solution using a sodium hydroxide solution, in order to remove N ₂ O ₄ remaining in the nonwoven fabric, isopropyl alcohol and water were mixed at a volume ratio of 40:50 to 60:40. Washed several times and dried in air to prepare a biodegradable cellulose nonwoven fabric consisting of nanofibers.

The cellulose oxide nonwoven fabric prepared according to the embodiment of the present invention is quickly absorbed in the human body when used for medical purposes, and the carboxyl group formed through the formation of an aldehyde group in the oxidation process is formed by cleavage and hydrolysis of glucoside bonds. Promote decomposition. Therefore, it is possible to apply to medical fields such as hemostatic agents and anti-adhesion agents. Figure 4 shows the decomposition behavior of the cellulose oxide having a carboxyl group of 20.5% as the cellulose oxide nonwoven fabric swells while absorbing the surrounding solution and gradually gelation proceeds as the gel structure starts to lose the fiber structure from the second immersion time 3 days The fiber structure is almost lost, and it is present as a droplet from 4 days, and completely decomposes after 6 days.

Hereinafter, the Example and comparative example of this invention are demonstrated in detail.

Example 1

Ethanol was added to the mixed solution of acetone and distilled water in a 90:10 weight ratio to prepare an aqueous solution, and then 15 wt% of cellulose acetate was added to prepare a spinning solution. The spinning solution was spun at a spinning distance of 11 cm with a voltage of 14 kV to prepare a nonwoven fabric of 300 to 400 nm. Next, the cellulose nano nonwoven fabric was deacetylated with a solution of potassium hydroxide and ethanol for 3 hours, and the N ₂ O ₄ solution was reacted at 25 ° C. for 20.0 hours. In order to remove the N ₂ O ₄ , a biodegradable cellulose nonwoven fabric composed of nanofibers is prepared by washing several times with a solution having a volume ratio of isopropyl alcohol and water of 50:50 and drying in air. In order to observe the biodegradability of the prepared cellulose oxide nonwoven fabric, 25 g of a buffer solution having a pH of 7.0 was added thereto, and then 0.1 g of cellulose oxide nonwoven fabric was added to observe the degradation behavior at 37 ° C. Figure 5 is a photograph showing the decomposition behavior of the cellulose oxide non-woven fabric prepared from Example 1.

Examples 2-7

The same procedure as in Example 1, except that the reaction time with the N ₂ O ₄ solution was 5.0, 7.5, 10.0, 12.5, 15.0 and 17.5 hours to prepare a cellulose oxide nonwoven fabric.

Comparative Example 1

A cellulose oxide nonwoven fabric was prepared in the same manner as in Example 1 except that the reaction time with the N ₂ O ₄ solution was 2.5 hours.

division Response time (hrs) Disintegration days Example 1 20.0 5 Example 2 5.0 16 Example 3 7.5 14 Example 4 10.0 12 Example 5 12.5 10 Example 6 15.0 8 Example 7 17.5 6 Comparative Example 1 2.5 Almost no decomposition

The present invention described above is not limited to the above-described embodiment and the accompanying drawings, and various substitutions, modifications, and changes are possible within the scope without departing from the technical spirit of the present invention. It will be evident to those who have knowledge of.

1 is a result of observing the change of the cellulose nano nonwoven fabric according to the oxidation reaction time by Fourier Transform-Inforared Spectroscope (FT-IR).

Figure 2 is a graph showing the change in the carboxyl content of the cellulose nonwoven fabric with oxidation time and temperature change.

Figure 3 is a graph showing the weight loss change of the cellulose oxide nonwoven fabric according to the oxidation reaction time in a buffer solution of 37 ℃, pH 7.0.

Figure 4 shows the decomposition behavior of the cellulose oxide non-woven fabric having a carboxyl content of 20.5% in a buffer solution of 37 ℃, pH 7.0.

5 is a polaroid photograph showing the decomposition behavior of the cellulose oxide nonwoven fabric.

Figure 6 shows a scanning electron micrograph of a cellulose oxide nonwoven fabric composed of nanofibers prepared by one embodiment of the present invention.

Claims (9)

In the method for producing a biodegradable cellulose nonwoven fabric, Preparing an aqueous solution by adding distilled water and ethanol to acetone and dissolving 10 to 30% by weight of cellulose acetate in the aqueous solution; Preparing a non-woven fabric by electrospinning the solution in which the cellulose acetate is dissolved and then deacetylating the solution; Oxidizing the nano-nonwoven fabric to an N ₂ O ₄ solution; Neutralizing the N ₂ O ₄ solution using sodium hydroxide solution; And Washing the neutralized nonwoven fabric in a mixed solution of isopropyl alcohol and water and drying in air, The oxidation reaction uses a liquid phase oxidation method, The time for oxidizing the nano nonwoven fabric to the N ₂ O ₄ solution is 5 to 20 hours, characterized in that the method for producing a biodegradable cellulose oxide nonwoven fabric consisting of nanofibers. The method of claim 1, The method of producing a biodegradable cellulose nonwoven fabric consisting of nanofibers, characterized in that the spinning at a voltage of 10 to 40KV and a spinning distance of 5 to 20cm during the electrospinning. The method of claim 1, The temperature for oxidizing the nano nonwoven fabric to the N ₂ O ₄ solution is 25 to 35 ℃ manufacturing method of biodegradable cellulose oxide nonwoven fabric consisting of nanofibers. delete The method of claim 1, When the neutralized nonwoven fabric is washed with a mixed solution of isopropyl alcohol and water, the ratio of isopropyl alcohol and water is 40:50 to 60:40 by volume. . In the biodegradable cellulose oxide nonwoven fabric, It is prepared by dissolving 10-30% by weight of cellulose acetate in an aqueous solution prepared by adding distilled water and ethanol to acetone, followed by electrospinning, and then oxidizing and deacetylating a nano nonwoven fabric to a N ₂ O ₄ solution. The oxidation reaction uses a liquid phase oxidation method, the time for oxidizing the nano nonwoven fabric to the N ₂ O ₄ solution is reacted for 5 to 20 hours, Biodegradable cellulose oxide nonwoven fabric consisting of nanofibers that can be used as a medical hemostatic or anti-adhesion agent. The method of claim 6, Biodegradable cellulose nonwoven fabric consisting of nanofibers, characterized in that the spinning at the voltage of 12 to 16KV and the spinning distance of 10 to 12cm during the electrospinning. The method of claim 6, Biodegradable cellulose oxide nonwoven fabric consisting of nanofibers, characterized in that the temperature of the nano nonwoven fabric oxidized to N ₂ O ₄ solution is 25 to 35 ℃. The method of claim 6, Biodegradable cellulose oxide nonwoven fabric consisting of nanofibers, characterized in that the time for the oxidation reaction of the nano nonwoven fabric to N ₂ O ₄ solution is 5 to 20 hours.

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