METHOD OF MANUFACTURING ANTIBACTERIAL SUPERABSORBENT POLYMER ABSORBER CONTAINING METAL NANOPARTICLES
20190345600 ยท 2019-11-14
Inventors
Cpc classification
B01J20/3208
PERFORMING OPERATIONS; TRANSPORTING
A61L2400/12
HUMAN NECESSITIES
A61L2300/404
HUMAN NECESSITIES
A61F2013/530489
HUMAN NECESSITIES
B01J20/3236
PERFORMING OPERATIONS; TRANSPORTING
A61L15/60
HUMAN NECESSITIES
C08J3/128
CHEMISTRY; METALLURGY
B65D81/34
PERFORMING OPERATIONS; TRANSPORTING
A01G24/00
HUMAN NECESSITIES
A61F2013/16
HUMAN NECESSITIES
A61L2300/102
HUMAN NECESSITIES
C08J2333/02
CHEMISTRY; METALLURGY
International classification
A61L15/60
HUMAN NECESSITIES
Abstract
The present invention relates to a method of manufacturing a superabsorbent polymer absorber containing metal nanoparticles and an application of the superabsorbent polymer absorber which is manufactured by the same and has antibacterial, sterilization, far infrared ray emission, prevention of blood oxidation, and mineral releasing functions. Specifically, the present invention relates to a technique in which metal nanoparticles such as copper, brass, bronze, silver, gold, germanium, and zinc are formed on the superabsorbent polymer by using a water-free manufacturing method, then, when the superabsorbent polymer absorbs water, the metal nanoparticles are naturally and uniformly dispersed, thereby allowing the superabsorbent polymer to exhibit inherent properties of the metal nanoparticles, and an application thereof.
Claims
1. A method of manufacturing a superabsorbent polymer absorber containing metal nanoparticles deposited on a surface thereof, the method comprising: (a) preparing superabsorbent polymer particles in a dried state; and (b) depositing metal nanoparticles on surfaces of the superabsorbent polymer particles.
2. The method according to claim 1, wherein the step of depositing the metal nanoparticles on the surfaces of the superabsorbent polymer particles is performed in a vacuum deposition bath by a vacuum deposition method.
3. The method according to claim 2, wherein the vacuum deposition method comprises: generating metal vapor particles while stirring the superabsorbent polymer in a vacuum deposition bath provided with a stirring bath containing the superabsorbent polymer and a metal deposition source, so as to allow metal nanoparticles to be directly adhered to the superabsorbent polymer particles.
4. The method according to claim 3, wherein the metal deposition source is selected from the group consisting of thermal deposition, electron beam deposition, DC sputtering, cathode arc deposition, DC magnetron sputtering, RF sputtering, ion beam sputtering, molecular beam epitaxy, arc discharge method and laser ablation.
5. The method according to claim 1, wherein the metal is selected from the group consisting of silicon (Si), copper (Cu), zinc (Zn), brass, aluminum (Al), beryllium (Be), magnesium (Mg), germanium (Ge), strontium (Sr), barium (Ba), yttrium (Y), titanium (Ti), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta), lanthanum (La), silver (Ag), gold (Au), platinum (Pt), palladium (Pd) and an oxide thereof.
6. The method according to claim 1, wherein the superabsorbent polymer has CO, COOH, OH, NH, or NH.sub.2 functional groups polymer chains, and the polymer chains are cross-linked.
7. The method according to claim 6, wherein the superabsorbent polymer has a water absorbing potential of 100 to 1000 times based on an initial volume thereof.
8. A water absorption or control product, comprising: the superabsorbent polymer absorber prepared by the method according to claim 1; and materials having functions of absorbing water or allowing water to pass, which are mixed with the superabsorbent polymer absorber.
9. The water absorption or control product according to claim 8, wherein the water absorption or control product is a diaper, a sanitary napkin, a food packing absorber, a blood absorbing band for medical applications, or a product configured to control the moisture in the soil for crops.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0037] The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the Office upon request and payment of the necessary fee.
[0038] The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
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DETAILED DESCRIPTION OF THE INVENTION
[0053] The present invention provides a method of manufacturing a superabsorbent polymer absorber containing metal nanoparticles deposited on a surface thereof, the method including: (a) preparing superabsorbent polymer particles in a dried state; and (b) depositing metal nanoparticles on surfaces of the superabsorbent polymer particles.
[0054] Hereinafter, the present invention will be described in detail. Terms or words used in the specification and claims should not be construed as limited to a conventional or lexical meaning, and should be understood as appropriate notions by the inventor based on that he/she is able to define terms to describe his/her invention in the best way to be seen by others.
[0055] A superabsorbent polymer absorber containing the metal nanoparticles prepared by a manufacturing method of the present invention has new functions such as antibacterial, sterilization, reduction and prevention of mineral loss due to the added metal nanoparticles, in addition to natural roles of the superabsorbent polymer such as an absorption of moisture from a flow of water and a prevention of rapid loss of mineral nutrients. The superabsorbent polymer absorber containing such metal nanoparticles may be used alone or in combination with conventional superabsorbent polymers to produce various products. In addition, it is preferable that the superabsorbent polymer absorber of the present invention is used together with a separation membrane made of various nonwoven fabrics or the like for preventing the nanoparticles from escaping to an outside. Further, when using the superabsorbent polymer absorber of the present invention by variously mixing with conventional natural and artificial fiber materials, it is possible to prevent the propagation of various bacteria contained in the liquid while absorbing various nutrient-containing liquids discharged from animals and plants.
[0056] The present invention provides a method of forming metal nanoparticles having an antibacterial, sterilizing, or reducing power, as well as, functions such as a far infrared ray emission, or mineral releasing on the superabsorbent polymer used as an absorber. The present invention relates to a method of forming metal nanoparticles having antibacterial/sterilizing functions on the superabsorbent polymer, by a method in which water and other impurities are not contained at all without an additional process such as moisture removal and impurity removal for solving the problems entailed in the conventional chemical method.
[0057] In addition, the present invention also relates to a use of the superabsorbent polymer absorber deposited with metal nanoparticles prepared by such a physical method. Since the present invention relates to a method of manufacturing an antibacterial superabsorbent polymer, and metal nanoparticles are added while maintaining the superabsorbent function of the superabsorbent polymer, the metal nanoparticles are formed in a uniform particle diameter. The metal nanoparticles having various functions may increase antibacterial properties due to a high dispersibility. In addition, since metal nanoparticles are present in an initial passage for absorbing nutrients along with water on the surface of the superabsorbent polymer, the nutrients come into contact with metal nanoparticles from the initial absorption process, and thereby effectively providing high antibacterial effects even at a low concentration.
[0058] Further, since the method of the present invention is a physical vacuum process, there is no inflow of impurities, and the main causative substances that pollute the environment are not discharged. In addition, since the various metal nanoparticles may be formed simultaneously or stepwise and a water-free process is employed, the formed metal nanoparticles may be stored for a long period of time. Further, the metal nanoparticles are kept in a stable state, such that the antibacterial and sterilizing abilities may be exerted regardless of the preservation period.
[0059]
[0060] It is preferable that the superabsorbent polymer containing metal nanoparticles deposited on the surface thereof is prepared by a method in which the superabsorbent polymer is used as a carrier in a vacuum deposition bath, and metal nanoparticles are vacuum deposited on the surface of the carrier.
[0061] Herein, the vacuum deposition will be described in more detail. The vacuum deposition may be performed by using an apparatus for vacuum depositing metal particles, which includes: a vacuum deposition bath; a stirring bath provided at a lower part of the vacuum deposition bath; a screw provided in the stirring bath to stir the carrier, that is, a superabsorbent polymer chip; and a metal deposition source provided at an upper part of the stirring bath in the vacuum deposition bath to generate metal vapor particles. A vacuum level in the vacuum deposition bath may be controlled to be in a range of 10.sup.4 to 10.sup.6 torr. When the vacuum level is less than 10.sup.4 torr, vapor particles for forming nanoparticles are deposited thickly on the carriers near the metal deposition source for generating vapor particles in a low vacuum, whereas, as the carriers move away from the metal deposition source, a mean free movement distance of the vapor particles is shortened, such that vapor particles are not deposited on the carrier.
[0062] In the vacuum deposition, a rotation speed of the screw for stirring the superabsorbent polymer is preferably controlled to be in a range of 1 to 200 rpm, preferably 10 to 100 rpm. If the stirring speed is less than 1 rpm, there is a problem that the metal vapor particles are not uniformly adhered to the chip surface of the polymer since sufficient stirring is not performed. If the stirring speed exceeds 200 rpm, there is a problem that the stirred superabsorbent polymer particles are scattered and adhered to the metal deposition source, thereby causing electrical short-circuit.
[0063] The vacuum level in the vacuum deposition bath is controlled by including an inert gas. Herein, the inert gas may include argon (Ar), neon (Ne), N.sub.2, O.sub.2, CH.sub.4 and the like.
[0064] In the step of generating vapor particles for forming nanoparticles using the above-described metal deposition source, physical vapor deposition methods may be used. As one example of the physical vapor deposition methods, thermal deposition such as a resistance heating method, plasma heating method, induction heating method and laser heating method, DC sputtering, DC-RF sputtering, laser sputtering, E-Beam evaporation and the like.
[0065] In the present invention, a deposition time may be set to be 10 minutes to 20 hours. By controlling the deposition time, the concentration of the metal particles with respect to the superabsorbent polymer may be controlled. That is, the deposition time may be controlled within the time range in order to maintain the concentration of the metal particles with respect to the superabsorbent polymer in a range of 100 to 3000 ppm depending on a concentration suitable for killing the bacteria or applications.
[0066] The vacuum deposition may control the growth of the nanoparticles by controlling the vacuum level in the deposition bath, the rotation speed of the screw, the deposition time, the deposition power, etc., such that the particle diameter and amount of the metal nanoparticles deposited on the superabsorbent polymer may be controlled.
[0067] Herein, any metal nanoparticle may be used so long as it is a nanoparticle of metal having antibacterial and sterilizing properties, and may include at least one selected from the group consisting of silicon (Si), copper (Cu), zinc (Zn), brass, aluminum (Al), beryllium (Be), magnesium (Mg), germanium (Ge), strontium (Sr), barium (Ba), yttrium (Y), titanium (Ti), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta), lanthanum (La), silver (Ag), gold (Au), platinum (Pt), palladium (Pd) and an oxide thereof. Preferably, metals such as copper, silver, zinc, brass, and bronze are used.
[0068] The metal nanoparticles have a mean particle diameter of 2 to 30 nm, and preferably 2 to 10 nm.
[0069] When the nanoparticles are formed so as to have a particle diameter within the above range, aggregation between the nanoparticles is prevented, and the metal nanoparticles are well dispersed together with the absorption of water, such that metal nanoparticles having uniform properties may be achieved. That is, the nanoparticles prepared by the method of the present invention have a particle diameter of 2 to 30 nm, and preferably 2 to 10 nm, which is smaller than the particle diameter (50 to 100 nm) of the particles used in the metal vapor condensation method. Therefore, the surface area of the metal nanoparticles may be increased by a small amount. Further, there is no need for a separate process for removing a solvent or a dispersant by depositing the nanoparticles on the superabsorbent polymer without using a chemical dispersant, or a solvent.
[0070] Meanwhile, in a case of the prior art, a large amount of antimicrobial agent should be added because the nanoparticles are agglomerated together during the process due to insufficient dispersion. As a result, the price is not competitive and there is a limitation in an aspect of durability for the performance of the product using the superabsorbent polymer. On the other hand, the nanoparticles prepared by the method of the present invention are converted from raw materials to nanoparticles as they are, and addition or inflow of other foreign materials is prevented, such that there are advantages that the nanoparticles have a high purity, and excellent uniformity, without affecting properties of the superabsorbent polymer.
[0071] The superabsorbent polymer of the present invention is a polymer which is easily hydrogen-bonded to a water molecule (H.sub.2O) such as CO, COOH, OH, NH, NH.sub.2 or the like in a polymer chain, thereby having many functional groups capable of adsorbing water. In addition, the superabsorbent polymer refers to a polymer in which a certain amount of chains are cross-linked, and in the absence of moisture, the polymer chains retain completely twisted, whereas, when absorbing moisture, the polymer chains expand due to swelling, such that the polymer does not dissolve by crosslinking, and thereby having water absorbing potential to absorb 100 to 1000 times water based on an initial volume of the polymer.
[0072] As the superabsorbent polymer, any one may be used so long as it is a superabsorbent polymer in a form of particles conventionally used in the art without limitation thereof. As an example of the superabsorbent polymer, there is a polymer having a functional group such as CO, COO, OH, or NH which is a hydrophilic functional group capable of being hydrogen-bonded with water. Specifically, a hydrogel polymer, which is prepared by polymerizing a water-soluble ethylene unsaturated monomer or a monomer composition including a (meth)acrylate monomer and a polymerization initiator, may be used.
[0073] Preferably, the superabsorbent polymer particles used in the manufacturing method of the present invention have a mean particle diameter of 0.1 to 5 mm, and preferably 0.3 to 3 mm. If the metal nanoparticles have a particle diameter within the above range, after the metal nanoparticles are deposited on the surface of the polymer, and when the polymer absorbs the liquid to swell, the nanoparticles move into the polymer together with the liquid to exhibit an antibacterial effect or the like.
[0074] The present invention may use a commercially available 90 percent by weight (wt. %) or more of dried superabsorbent polymer as it is, and may add a drying process if necessary.
[0075] The superabsorbent polymer absorber containing the metal nanoparticles deposited on the surface thereof prepared by the method of the present invention may be mixed with existing materials having functions of absorbing water or allowing water to pass, and the like, thus to perform various combinations of functions, for example, it can be utilized as a diaper, sanitary napkin, food packing absorber, blood absorbing band for medical applications and the like. In this case, due to the nanoparticles formed on the superabsorbent polymer, it is possible to perform an antibacterial or sterilizing function, enhancement of blood reducing action, far-infrared emission, moisture control in the target product or in the soil for crops, and sustained emission of minerals.
[0076] A water absorption or control product may be prepared by mixing the superabsorbent polymer absorber containing metal nanoparticles deposited on the surface thereof according to the present invention with materials having functions of absorbing water or allowing water to pass.
[0077] The water absorption or control product may be a diaper, a sanitary napkin, a food packing absorber, a blood absorbing band for medical applications, or a product configured to control the moisture in the soil for crops.
[0078] Hereinafter, the present invention will be described in detail with reference to examples. However, the examples according to the present invention may be modified into various other forms, and the scope of the present invention should not be construed as being limited to the embodiments described below. The examples of the present invention are provided to enable those skilled in the art to more fully understand the present invention.
<Example 1> Preparation of Superabsorbent Polymer Absorber Containing Metal Nanoparticles Deposited on the Surface Thereof
[0079] 1-1. A disk type copper (Cu), bronze or silver (Ag) target having a diameter of 10 cm and a thickness of 1 cm was adhered to a DC sputtering cathode. 2-propenoic acid homopolymer sodium salt (sodium polyacrylate) containing 0-8 wt. % of water, which is produced by LG Chem, was used as a superabsorbent polymer. The polymer chip was introduced into a stirring bath in a vacuum deposition bath, then a door of the vacuum deposition bath was closed, followed by starting vacuum evacuation. The introduced polymer chip had a weight of 6.5 kg. After making a lower vacuum state of 110.sup.2 Torr inside of the stirring bath by using a rotary pump, the inside of the stirring bath was made into a high vacuum state of 110.sup.5 Torr by using an oil diffusion pump.
[0080] In the high vacuum state, Ar gas was injected into the vacuum deposition bath at a flow rate of 50 to 150 sccm, and the polymer chip was stirred at a speed of 60 rpm. At this time, injection of Ar gas is carried out to generate a plasma for deposition, and stirring of the superabsorbent polymer powders is carried out so that the particles to be deposited are maintained at a fine size without being coarse. When applying power to a DC power supply, a plasma was generated and deposition of metal particles was started. The deposition was carried out for 3 hours, and the concentration of the deposited metals was 0.1 wt. %, respectively.
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<Example 2> Experiment for Absorbency
[0083] The manufacturing process of the present invention was performed in a vacuum state in which no water was used while having no connection with water. Therefore, an absorption rate of the superabsorbent polymer deposited with the metal nanoparticles of the present invention is similar to that of the initial superabsorbent polymer.
[0084] 1.1 g of superabsorbent polymer (Zn/SAP) deposited with zinc nanoparticles, superabsorbent polymer (Ag/SAP) deposited with silver nanoparticles, and a mixture of Ag/SAP and Zn/SAP were put in typical beverage containers, respectively, then 300 ml of water was added thereto, and the appearances thereof were observed, respectively, and results thereof are shown in
[0085]
<Example 3> Experiment for Antibacterial Property
[0086] A test for antibacterial activity of an absorber for a food packing material used for absorbing liquids from meats, fishes, and fruits by using the super absorbent polymer of the present invention was carried out. An antibacterial test was performed on the superabsorbent polymer having silver nanoparticles formed thereon by using an adhesion test method with film (JIS Z 2801), and results of the test were shown in the following tables. Bacteria used in the test were Staphylococcus aureus (SA), Klebsiella pneumoniae (KP), and Escherichia coli, and an aspect of changes for each strain are shown in Table 1, Table 2 and Table 3 below. No treatment was performed in the control group. The antibacterial activity values against bacteria were 6.3, 6.4 and 6.3 in cases of Staphylococcus aureus, Klebsiella pneumoniae, and Escherichia coli, respectively, in the experiment group, which showed much higher values than those of the typical antimicrobial agents.
TABLE-US-00001 TABLE 1 Staphylococcus aureus Control group Experiment group Initial number of bacteria 1.8 10.sup.4 1.8 10.sup.4 After 24 hours 1.9 10.sup.4 <0.63 Antibacterial activity value 6.3
TABLE-US-00002 TABLE 2 Klebsiella pneumoniae Control group Experiment group Initial number of bacteria 1.1 10.sup.5 1.1 10.sup.5 After 24 hours 4.7 10.sup.7 <20 Antibacterial activity value 6.4
TABLE-US-00003 TABLE 3 Escherichia coli Control group Experiment group Initial number of bacteria 1.3 10.sup.4 1.4 10.sup.4 After 24 hours 1.3 10.sup.4 <20 antibacterial activity value 6.3
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<Example 4> Experiment of Food Storage CapabilitySeafood
[0088] A conventional superabsorbent polymer and the superabsorbent polymer having the zinc nanoparticles formed thereon of the present invention were put into a typical zipper packing material, and a mackerel was stored at room temperature up to the 10th day, then a degree of decay was determined, respectively.
[0089] The experimental results are shown in
[0090] As illustrated in
[0091] On the other hand, as illustrated in
<Example 5> Experiment of Food Storage CapabilityMeats
[0092] A conventional superabsorbent polymer and the superabsorbent polymer having zinc nanoparticles formed thereon of the present invention were put into a typical zipper packing material, and a pork was stored at room temperature up to the 10th day, then a degree of decay was determined, respectively.
[0093]
[0094] As illustrated in the photograph of
<Example 6> Experiment of Food Storage CapabilityRice
[0095] A conventional superabsorbent polymer and the superabsorbent polymer having zinc nanoparticles formed thereon of the present invention were put into a typical zipper packing material, and rice was stored at room temperature up to 7th day, then a degree of decay was determined, respectively.
[0096]
[0097] As illustrated in the photograph of
[0098] On the other hand, it can be seen that, in a case in which the Zn/SAP of the present invention was added to the typical zipper packing material in