KR20180045420A - Manufacturing method of antibacterial materials using cation exchange reaction and antibacterial materials manufactured therefrom - Google Patents

Abstract

The present invention relates to a preparation method of an antibacterial material and the antibacterial material prepared thereby. The preparation method comprises: a first step of preparing a silver-containing zeolite through a cation exchange reaction of sodium cations (Na^+) and silver cations (Ag^+); and a second step of adding a thermoplastic resin and a dispersant to the silver-containing zeolite. The preparation method according to the present invention can prepare the antibacterial material with increased antibacterial properties by adjusting a mole ratio of the sodium cations and the silver cations in the zeolite through the cation exchange reaction, and can prepare the antibacterial material with improved dispersibility by adding the dispersant to the silver-containing zeolite.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an antibacterial material using a cation exchange reaction and an antibacterial material produced by the method.

The present invention relates to a method for producing an antibacterial material. Specifically, the present invention relates to a method for producing an antimicrobial material which improves antimicrobial activity through a cation exchange reaction between a sodium cation and a silver cation, and increases the dispersibility by using a dispersant, and an antibacterial material produced thereby.

As interest in hygiene has increased recently, interest in antibacterial materials is increasing in food, medical devices, pharmaceuticals, electronic devices, and textiles. In particular, the food packaging market is expected to reach about $ 300 million by 2019.

In the case of such antibacterial materials, metal ions such as zinc, copper, and silver ions are known to exhibit antimicrobial activity. Among them, inorganic antibacterial materials in which antimicrobial ions are immersed in an inorganic carrier are continuously attracting attention.

The inorganic antibacterial material is obtained by immersing metal ions such as zinc, copper or silver ions exhibiting antimicrobial activity in an inorganic carrier. The inorganic carrier is added to a resin or the like and mixed to provide an inorganic antibacterial material having an antibacterial effect.

However, when the metal ions are immersed in the inorganic carrier, there may be a problem that the antibacterial ability is decreased when the cation existing in the inorganic carrier is large.

In addition, when an antimicrobial ion is added to a resin in order to provide an inorganic antibacterial material, the compatibility with the resin is decreased, resulting in the phenomenon that the antibacterial ion is coagulated locally in the resin, there was.

Accordingly, the inventors of the present invention invented an antibacterial material having an excellent antimicrobial effect in an inorganic carrier by controlling the molar ratio of silver cation and sodium cation in zeolite, which is an inorganic carrier, by controlling the silver cation concentration.

In addition, by adding a dispersant, dispersibility of the antibacterial material is increased, and the present invention has been completed which exhibits the antimicrobial effect well.

Korean Patent Publication No. 1997-0025627

An object of the present invention is to provide a method for producing an antimicrobial material in which a zeolite containing silver is prepared through a cation exchange reaction and a dispersant is added thereto to improve the dispersibility, and an antibacterial material produced thereby.

A first aspect of the present invention is a method for producing a zeolite comprising the steps of: preparing a zeolite containing silver through a cation exchange reaction between a sodium cation (Na ⁺ ) and a silver cation (Ag ⁺ ); And a second step of adding a thermoplastic resin and a dispersant to the zeolite containing silver.

A second aspect of the present invention provides an antibacterial material produced by the first aspect.

Hereinafter, the present invention will be described in detail.

The present invention can provide a method for producing an inorganic antibacterial functional powder material by replacing a sodium cation in a zeolite with a silver cation having antimicrobial activity through a cation exchange reaction using Zeolite 4A type.

The present invention can be produced by ion-exchanging a large amount of a silver cation (Ag ⁺ ) with a sodium cation (Na ⁺ ) in a zeolite. At this time, in addition to the sodium cation, a substitutable cation such as Ca ^{2 +} and Mg ^{2 +} can be substituted for the silver cation. The silver cations according to the invention are present in the zeolite in ionic bonding.

The silver cation-containing zeolite kills bacteria in a manner that interferes with the protein synthesis of the microorganisms, thereby exhibiting sterilization and antibacterial effects.

For example, the zeolite containing a silver cation according to the present invention can dissolve cations in water, and the eluted silver cations adsorb and bind to the ^- SH, COO ^- , or OH ^- ions of microbial proteins, And can lead to a condensation-dehydration reaction, which makes bacterial metabolism and energy metabolism difficult to breathe, thereby killing bacteria.

Silver which can be used in the present invention may mean a silver cation. For example, silver cations are present in liquid form, mostly in the form of Ag ⁺ ions, except for AgCl, and it may be difficult to form silver cations as solids. Especially in the case of AgCl, the bond is strong in the metal bond, so silver cation formation may be difficult.

On the other hand, silver (Ag) fine powders and the like do not form silver cations, and silver cations have antibacterial power.

The zeolite may be defined as crystalline aluminosilicate having a plurality of pores. The zeolite is an inorganic polymer material formed by three-dimensionally connecting silicon (Si) and aluminum (Al) via oxygen atoms, and usually has a fine crystal size of 1 μm. They are structurally characterized in that they have various shapes and nanopores of 0.3 nm to 10 nm depending on the type.

In the present invention, the zeolite is selected from the group consisting of A type zeolite, X type zeolite, Y type zeolite, high silica zeolite, sodium dodecylate, mordenite, annenite, clinoptilolite, cabilite and enynonite It can be more than one.

Preferably, the zeolite used in the present invention can be used without restrictions as long as it has cations such as Na ⁺ , Ca ^{2 +} , K ^+, and the like.

More preferably, the zeolite may be Zeolite 4A type.

Preferably, the molar ratio of the sodium cation to the silver cation may be 1: 0.5 to 1: 1.5. When the molar ratio of the sodium cation to the silver cation is less than 1: 0.5, the antibacterial activity may be lowered. If the molar ratio of the sodium cation to the silver cation is more than 1: 1.5, there may be a problem in that the reaction does not occur and the silver cations remaining in the expensive silver ion are wasted.

In one embodiment, the molar ratio of sodium cations and silver cations can be 1: 1.2.

The cation exchange reaction of the first step may occur at a pH of 7 to 6.4.

At this time, when the pH is in the range of 7 to 6.4, hydrogen peroxide is more easily formed in water than water in the formation of H ⁺ ions and OH ^- ions, and they act as catalysts for ion exchange to further increase the reaction rate , The cation exchange reaction can occur smoothly.

Preferably, the substance for adjusting the pH may be at least one selected from hydrogen peroxide (H ₂ O ₂ ), acetic acid, and sulfuric acid. However, in the case of hydrochloric acid, Ag ⁺ ion and Cl ^- ion are combined to form AgCl, which is insoluble in water and precipitates, which can be excluded.

In one embodiment, the third step of heating the product of the second step to 110 to 200 캜.

Preferably, the dispersing agent may be calcium carbonate, talc, zinc oxide, or zinc stearate.

Preferably, the content of the dispersant may be 0.01 to 5% by weight based on the thermoplastic resin. If the content of the dispersing agent is less than 0.01% by weight, there is a problem that the dispersion of silver zeolite does not help. If the content of the dispersing agent exceeds 5% by weight, there may be problems such as a decrease in the strength of the antibacterial material, a decrease in transparency, and an increase in haze.

The thermoplastic resin may be at least one selected from the group consisting of PP (PolyPropylene), PE (PolyEthylene), PVC (polyvinyl chloride), EVA (Ethylene-Vinyl Acetate), Nylon and PET (poly ethylen terephthalate).

In the present invention, the zeolite containing silver may further include a thermoplastic resin. When the zeolite containing silver further contains a thermoplastic resin, even if the thermoplastic resin is structurally high in viscosity, if the amount of the silver cation is sufficiently large, silver ions having good dispersion are present on the surface of the thermoplastic resin, It can cause enough disability. As a result, the whole thermoplastic resin has an antibacterial effect.

The antimicrobial material may be in the form of a film.

The cation exchange reaction can be carried out by passing a silver precursor through a column filled with a zeolite containing a sodium cation.

The column can be used without limitation as long as it is commonly used in the art.

By passing the silver precursor through the column filled with zeolite, the silver precursor remaining after use can be reused, and the amount of silver precursor that can be used can be controlled more precisely. In addition, this can reduce the consumption of expensive silver.

The cation exchange reaction can be carried out by adding silver precursor and hydrogen peroxide together.

According to the present invention, an antimicrobial material having enhanced antimicrobial activity can be prepared by controlling the molar ratio of sodium cations and silver cations in the zeolite through a cation exchange reaction.

According to the present invention, an antimicrobial material having improved dispersibility can be prepared by adding a dispersant to the zeolite containing silver.

According to the present invention, it is also possible to prepare a composite in which the Zeolite 4A type is immersed in an aqueous solution of silver nitrate (1N) to obtain a 99.99% antimicrobial function even when 0.1 wt% of Ag-Zeolite in which silver cations and silver cations are exchanged is polypropylene .

1 is a schematic diagram of a method for producing an inorganic antibacterial powder material through a silver cation (Ag ⁺ ) substitution reaction.
2 is an XPS analysis graph of a powder sample according to the nitrate silver content.
3 is an XPS analysis graph of an Ag-Zeolite sample according to the molar ratio of sodium cation to silver cation.
FIG. 4 is a graph showing an Ag element binding energy (eV) analysis of each Ag-Zeolite sample.
5 is an EDS analysis graph of Zeolite 4A type powder.
6 is an EDS analysis graph of a cation (Ag ⁺ ) substituted powder sample (Ag-Zeolite 1.0).
7 is an EDS analysis graph of a cation (Ag ⁺ ) substituted powder sample (Ag-Zeolite 1.2).
Figure 8 is a schematic diagram of Ag-zeolite after completion of the cation exchange reaction.
9 is a schematic diagram of Ag-zeolite after completion of the cation exchange reaction.
10 is a schematic diagram of silver cation distribution in zeolite.
11 is an antibacterial test image for S. aureus strain.
12 is an antibacterial test image for E. coli strain.

Hereinafter, the present invention will be described in more detail with reference to Examples. These examples are for further illustrating the present invention, and the scope of the present invention is not limited by these examples.

Reference Example  : Basic Properties

Zeolite 4A type (Cosmo catalyst), silver nitrate solution (1M, Aldrich) and Methanol (Samchun) were used. The chemical composition of Zeolite 4A type is shown in Table 1.

Chemical composition Na ₂ O 17-19 Al ₂ O ₃ 28.5-29.5 SiO ₂ 33-34.5 H ₂ O 18-21

Example  1: Method for producing zeolite containing silver cations according to the number of moles of silver nitrate added

The silver nitrate was dissolved in deionized water to a constant concentration of 1M, and 4A type zeolite was loaded on the silver nitrate solution and stirred at 100 rpm for about 30 minutes using a mechanical stirrer. At this time, 3 ml of 35% hydrogen peroxide (H ₂ O ₂ ) was added so that the ion exchange occurred well. After the stirring was completed, the paper was squeezed using a filter paper or a fine pore cloth. Thereafter, the unreacted silver nitrate was washed three times with deionized water to remove the silver nitrate, and then filtered. Finally, the zeolite containing silver was dried at 110 DEG C for 6 hours or more in a forced circulation oven.

The amounts of added silver (Ag ⁺ ) ions according to Example 1 were 0.02 mol, 0.06 mol, 0.10 mol, and 0.12 mol, respectively, and specific compositions are shown in Table 2 below. Table 2 shows the composition of the Ag-Zeolite sample according to the number of moles of silver nitrate added.

As in Example 1, an antibacterial functional powder sample was prepared according to the number of moles of Ag cations in the silver nitrate aqueous solution. XPS analysis was carried out to determine the degree of substitution of the silver cation of the zeolite with the silver nitrate content, and the sample data was analyzed by selecting the Ag-Zeolite 2 having the smallest number of moles of the cation in the sample. The resultant data are shown in Experimental Example 1. [

Example  2: Cation-substituted zeolite according to the molar ratio of silver cation to sodium cation

XPS analysis of the zeolite was used to calculate the number of moles of silver and sodium cations in the silver nitrate and the zeolite, and a cation exchange sample was prepared based on the molar ratio of the silver and sodium cations. From this, an optimal cation exchange molar ratio analysis of the Zeolite 4A type used in the present invention was conducted. Specifically, the number of moles of sodium cation in the unit zeolite (per gram) was calculated, and the sodium cation molarity was substituted by changing the cationic molar ratio. The molar ratios of the silver cation and the sodium cation according to Example 2 were 1.0, 1.2, 1.4, 1.6, 1.8 and 2.0, respectively.

Sample name Factor ratio
(Ag mole / Na mole) Zeolite (g) AgNO3 (g) Deionized water (g) Remarks zeolite 10 Comparative Example 1 Ag-zeolite 1.0 1.0 68.10 81.90 Ag-zeolite 1.2 1.2 81.72 68.28 Ag-zeolite 1.4 1.4 95.34 54.66 Ag-zeolite 1.6 1.6 108.96 41.04 Ag-zeolite 1.8 1.8 122.58 27.42 Ag-zeolite 2.0 2.0 136.56 13.44

Comparative Example  1: silver-free zeolite

Was prepared in the same manner as in Example 2, except that the cation was not substituted.

Example  3: zeolite containing silver and polypropylene composite

In the case of Example 3, Ag-Zeolite 1.2 was selected as an optimal cation-exchange molar ratio sample based on XPS analysis through Example 2 and Experimental Example 2, and polypropylene (PP, polypropylene ) Composite pellet sample was prepared.

First, polypropylene, Ag-zeoilte, calcium carbonate, talc and zinc stearate were added to a henckel mixer and stirred at high speed. Well-mixed materials were compounded using Twin-screw extruder (Siemens). In this case, the mixed material was injected into the hopper of the twin extruder, the screw speed was 400-700 rpm and the extruder chamber temperature was 170, 180, 180, 180, 190, 190, 200, 210 (hopper, Respectively. After compounding, it was cooled by water cooling method.

From this, the antimicrobial powder content (wt%) under compound process conditions; 0.1, 0.5, 1.0, 3.0, 5.0 pellets samples were prepared.

Particularly, CaCO ₃ (average particle diameter 100 nm) was added to 1 wt% of polypropylene to improve the dispersibility of Ag-Zeolite.

Experimental Example  1: Analysis of zeolite containing silver according to the molar addition of silver

In order to confirm the substitution ratio of silver cation (Ag ⁺ ) according to the change of nitrate silver content, the XPS of the inorganic antibacterial powder material sample of each content was measured. In addition, the elemental composition ratio data of the samples were compared with the element composition of the conventional untreated zeolite, and the optimum concentration of silver nitrate was determined by observing changes in composition of silver and sodium elements. Table 4 shows the element composition ratios of the respective samples according to the addition amount of silver nitrate.

Sample name AgNO ₃ (ml) Ag3d O1s Na1s C1s Si2P Al2p Zeolite 0.53 46.47 10.54 13.83 15.02 13.6 Ag-Zeol 2 20 6.37 40.01 5.93 23.43 14.41 9.85 Ag-Zeol 6 60 14.57 46.08 0.64 12.57 12.82 13.33 Ag-Zeol 10 100 14.96 46.98 0 11.92 13.39 12.76 Ag-Zeol 12 120 14.26 45.74 0 13.08 13.32 13.61

As shown in FIG. 2, it was confirmed that the composition showed a composition similar to that of the Zeolite 4A type composition. In addition, the composition of silver cation and sodium cation for judging the degree of cation substitution reaction was found to increase to about 14-15% as the silver nitrate concentration increased, and the sodium cation was not detected after the decrease. As a result, it was confirmed that the cation exchange reaction was completely occurred after the Ag-Zeolite 6 sample, and it was confirmed that the silver nitrate silver solution was completely washed through the absence of nitrogen ion detection in all the samples.

Experimental Example  2: An aqueous solution of silver nitrate and an aqueous solution of zeolite Ag  And the calculation of the number of moles of Na cations

The XPS of each sample according to Example 2 was measured for the molar ratio of silver according to the mole of sodium of Zeolite 4A type, and the degree of cation exchange reaction according to the content of element was analyzed. Table 5 shows the element composition ratio of the Ag-Zeolite sample according to the Na and Ag mole ratios.

Sample name Component ratio
(Ag mol / Na mol) Ag3d O1s Na1s C1s Si2P Al2p Zeolite 0.55 48.63 13.36 10.46 14.12 12.89 Ag-Zeolite 1.0 1.0 12.83 41.72 0.19 16.13 17.46 11.66 Ag-Zeolite 1.2 1.2 11.89 37.64 None 14.40 24.93 11.15 Ag-Zeolite 1.4 1.4 11.78 37.10 None 13.64 25.78 11.70 Ag-Zeolite 1.6 1.6 13.45 42.05 None 14.96 18.49 11.05 Ag-Zeolite 1.8 1.8 12.24 38.67 None 13.51 24.98 10.60 Ag-Zeolite 2.0 2.0 11.97 38.30 None 14.94 24.81 9.98

As a result of XPS analysis, a small amount of sodium cation was detected in Ag-Zeolite 1.0 having a molar ratio of sodium cation and silver cation of 1: 1, and most of the sodium cation was substituted with silver cation. In this experiment, the optimum molar ratio was selected as Ag-Zeolite 1.2, which was not detected at the lowest concentration of sodium cation.

Cations of silver and sodium cations in silver nitrate and zeolite were calculated and cation exchange samples were prepared based on the molar ratio of silver and sodium. At this time, the optimal cation exchange molar ratio analysis of the Zeolite 4A type was conducted. Table 6 shows the elemental contents in Zeolite, Ag-Zeolite 1.0 and Ag-Zeolite 1.2.

3 shows an XPS analysis graph of an Ag-zeolite sample according to the molar ratio of sodium cation to silver cation.

FIG. 4 is a graph showing an Ag element binding energy (eV) analysis of each Ag-zeolite sample.

In order to visually confirm the degree of cation substitution according to the results of XPS analysis, EDS measurement was carried out, and Zeolite (4A type) without Ag element and Ag-Zeolite 1.2 sample with optimal cation substitution were used. As a control, incompletely cation- Zeolite 1.0 sample was analyzed.

5 is an EDS analysis graph of Zeolite 4A type powder. In the case of Zeolite 4A powder, it was confirmed that Ag ion was not detected and the content of Na was very high. In order to change the Na to Ag through nitric acid treatment, if the Na ion indicated by yellow is not detected, Indicates that it is complete.

6 is an EDS analysis graph of a silver cation (Ag ⁺ ) substituted powder sample (Ag-Zeolite 1.0). Unlike the conventional zeolite powders, in the case of the sample Ag-Zeolite 1.0 powder, a large amount of silver cations were detected, but the content of sodium cations was clearly decreased. A small amount of sodium cation was measured, but most of the cation exchange reaction was observed. In addition, no nitrogen element was detected and it was confirmed that the residue was completely washed after cation exchange reaction.

7 is an EDS analysis graph of a silver cation (Ag ⁺ ) substituted powder sample (Ag-Zeolite 1.2).

Figure 8 is a schematic diagram of Ag-zeolite after completion of the cation exchange reaction.

9 is a schematic diagram of Ag-zeolite after completion of the cation exchange reaction.

Ag₁₂[(AlO₂)·(SiO₂)]₁₂·27H₂O 일 수 있다. 10 is a schematic diagram of the distribution of silver cations in the zeolite. At this time, the structural formula of a zeolite is _{Na 12 [(AlO 2) ·} (SiO 2)] 12 · 27H 2 O

Ag ₁₂ [(AlO ₂ ). (SiO ₂ )] ₁₂ · 27H ₂ O.

Experimental Example  3: Analysis of zeolite-polypropylene composites

The pellets of each sample were prepared by using a hot press equipment (CARVER) to prepare sheets of each sample according to the content of Ag-Zeolite 1.2 of 10 cm × 10 cm and thickness 1 T. To analyze the antibacterial activity according to the content of the inorganic antibacterial material, An antimicrobial test (ISO 22196) analysis was conducted.

In the case of the sample Ag-Zeolite1.2 powder, it can be judged that the cation exchange reaction has proceeded because the sodium cation is not detected. Also, it is confirmed that the sample has the optimum molar ratio, Production and antibacterial activity test.

SIO 22196, Plastics-Measurement of antibacterial activity on plastics surfaces was used for antibacterial test analysis. Table 7 shows the antimicrobial test raw data for PP composite sheet samples of commercial antimicrobial (Zeomic) and Ag-Zeolite antimicrobials.

Claims (12)

A first step of preparing a zeolite containing silver through a cation exchange reaction between a sodium cation (Na ⁺ ) and a silver cation (Ag ⁺ ); And
A second step of adding a thermoplastic resin and a dispersant to the zeolite containing silver;
≪ / RTI >
The method according to claim 1,
Wherein the molar ratio of the sodium cation to the silver cation is 1: 0.5 to 1.5.
The method according to claim 1,
Wherein the cation exchange reaction in the first step occurs at a pH of 7 to 6.4.
The method according to claim 1,
And a third step of heating the product of the second step to 110 to 200 占 폚.
The method according to claim 1,
Wherein the zeolite is at least one selected from the group consisting of an A type zeolite, an X type zeolite, a Y type zeolite, a high silica zeolite, a sodium dodecylate, a mordenite, an annenite, a clinopyroylrite, a cabilite, , A method for producing an antibacterial material.
The method according to claim 1,
Wherein the dispersing agent is at least one selected from the group consisting of calcium carbonate, talc, zinc oxide, and zinc stearate.
The method according to claim 1,
Wherein the content of the dispersing agent is 0.01 to 5% by weight based on the thermoplastic resin.
The method according to claim 1,
Wherein the thermoplastic resin is at least one selected from the group consisting of PP (PolyPropylene), PE (PolyEthylene), PVC (polyvinyl chloride), EVA (Ethylene-Vinyl Acetate), Nylon and PET (poly ethylen terephthalate) Way.
The method according to claim 1,
Wherein the antibacterial material is in the form of a film.
The method according to claim 1,
Wherein the cation exchange reaction is carried out by passing a silver precursor through a column filled with a zeolite containing sodium cations.
11. The method of claim 10,
Wherein the cation exchange reaction is carried out by adding a silver precursor and hydrogen peroxide together.
An antimicrobial material produced by the method of any one of claims 1 to 11.

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