KR20130107098A - Building material having improved antibacterial effect and absorptivity, and method preparing for the same - Google Patents

Abstract

PURPOSE: A construction material with improved antibacterial activity and improved adsorptive power and a manufacturing method thereof are provided to prevent a sick house syndrome by having the adsorptive power on a volatility organic compound and excellent antibacterial activity. CONSTITUTION: A manufacturing method of a construction material with improved antibacterial activity and improved adsorptive power comprises as follows. Nanosilver particles are manufactured through a reduction sedimentation method. The nanosilver particles are coated on a composite for a building including activated carbon. The nanosilver particles use one dispersing agent among PVP, SDS, and Tween 20 and one reducing agent among hydrazine hydrate or NaBH4.

Description

Building material having improved antibacterial effect and absorptivity, and method preparing for the same}

The present invention relates to a building material and a method of manufacturing the improved antimicrobial power and adsorptive power to volatile organic compounds coated with silver nanoparticles in a building composition comprising activated carbon.

Sick House Syndrome, which has caused residents to feel health problems and discomfort due to harmful substances caused by various materials of new buildings, has recently been a problem.

Birdhouse syndrome is mainly caused by harmful components such as concrete and cement, which are the basis of building structures, and chemical components used in interior finishing materials such as wallpaper, ceiling, and flooring, and hundreds of adhesives used in the process of fixing the interior finishing materials. It is known to release harmful substances from eggplant. Specifically, examples of volatile organic compounds (VOCs) that cause sick house syndrome include formaldehyde, toluene, xylene, and the like. Formaldehyde is a volatile substance of formalin, and is widely used for building materials and adhesives in houses. Benzene compounds such as toluene and xylene are harmful chemicals suspected of causing cancer by being included in paints. In addition, harmful substances such as radon, asbestos, carbon monoxide, carbon dioxide, nitrogen oxides, ozone, fine dust, and airborne bacteria, which are generated during construction, are accumulated inside the building and can cause sick house syndrome.

Short-term exposure to these harmful substances can cause headache, eyes, nose and throat irritation, flatulence, itching, dizziness, nausea, decreased concentration, fatigue, and sensitivity to odors. It has been reported to cause pneumonia, high fever, heart disease and cancer.

Therefore, various measures have been proposed to reduce the damage of the sick house syndrome as described above. The methods include the removal of the harmful substances through ventilation or air purifying products, and the construction materials not containing harmful substances. The method of replacing with a material is used. However, the method using ventilation or air purifying products is not a method of post-treatment to quickly remove harmful substances that have already occurred, but to prevent the occurrence of chemical components that are the actual cause of sick house syndrome. Not only does it take a long time to remove the components, but the products for air purification also have poor removal efficiency for the unit area, and thus cannot be a fundamental measure.

Accordingly, the present inventors have made intensive efforts to manufacture new building materials. As a result, when coating silver nanoparticles on a building composition containing activated carbon to produce building materials, the inventors have very good antibacterial and adsorptive power to volatile organic compounds (VOCs). The present invention was completed by confirming.

Domestic patent application number: 10-2011-0023006

It is an object of the present invention to provide a method for producing a building material having improved antibacterial and adsorptive power to volatile organic compounds, including coating silver nanoparticles on activated carbon.

Still another object of the present invention is to provide a building material having improved adsorptive power to antibacterial and volatile organic compounds prepared by the above method.

In order to solve the above problems, the present invention provides a method for producing a building material with improved antimicrobial and adsorptive power to volatile organic compounds comprising the step of coating the silver nanoparticles in a building composition comprising activated carbon.

In addition, the present invention provides a building material having improved adsorptive power to the antibacterial and volatile organic compounds produced by the manufacturing method.

Building materials according to the present invention has superior antimicrobial activity and adsorption capacity for volatile organic compounds (VOCs) than conventional commercially available silver powder, when used as a building finishing material can prevent the sick house syndrome or building syndrome.

1 is a diagram showing a silver nanoparticle solution prepared using PVP having different concentrations as a dispersant.
FIG. 2 is a diagram showing a silver nanoparticle solution prepared using Tween 20 having a different concentration as a dispersant.
3 is a diagram showing a silver nanoparticle solution prepared using SDS having different concentrations as a dispersant.
Figure 4 is a diagram showing the antimicrobial activity of E. coli of the silver nanoparticles of the present invention.
5 is a diagram showing the adsorptivity of formaldehyde of the bamboo activated carbon coated silver nanoparticles of the present invention (top: before coating silver nanoparticles, bottom: after coating silver nanoparticles).
Figure 6 is a diagram showing the adsorption capacity of the activated carbon nano-coated bamboo activated carbon to benzene (top: before the silver nanoparticles coating, bottom: after the silver nanoparticles coating).

The present invention in one aspect,

(a) preparing silver nanoparticles; And

(B) coating the silver nanoparticles of the step (a) to a building composition comprising activated carbon; provides a method of manufacturing a building material improved anti-bacterial and adsorptive power to volatile organic compounds.

In still another aspect, the present invention provides a building material having improved antibacterial and adsorptive power to volatile organic compounds prepared by the method.

Hereinafter, the present invention will be described in detail.

In the method of manufacturing a building material of the present invention, step (a) is a step of preparing silver nanoparticles. The silver nanoparticles may be prepared by evaporation condensation or reduction precipitation, and preferably reduction reduction precipitation. When the silver nanoparticles are prepared by the reduction precipitation method, they may be prepared using any one or more dispersing agents including polyvinylpyrrolidinone (PVP), sodium n-dodecyl sulfate (SDS), and Tween 20 (polyoxyethylene sorbbitan monooleate). It may be prepared using a hydride (Hydrazine hydrate) or a reducing agent of any one of NaBH ₄ , but is not limited thereto.

The size of the silver nanoparticles is not limited thereto, but is 2 to 100 nm, preferably 5 to 50 nm.

Step (b) is a step of preparing activated carbon coated with silver nanoparticles, coating the silver nanoparticles on a building composition comprising activated carbon. At this time, the coating method may use a conventional method used in the art, for example, chemical vapor deposition, physical vapor deposition, chemical and electrochemical coatings Spraying, optical coatings, spin coating, dip coating, bar coating, UV coating, etc.

The activated carbon is made by treating wood, lignite, peat, etc. with a chemical agent such as zinc chloride or phosphoric acid as an activator, and drying or activating charcoal with water vapor.

The activated carbon is not limited thereto, but may be one using oak, oyster oak, prunus oak, beech, oak, pine, bamboo, cherry, birch, birch, mulberry, chestnut, palm, sawdust, etc. It is bamboo activated carbon.

As used herein, the term “volatile organic compound” refers to a liquid or gaseous organic compound which is easily evaporated into the atmosphere due to high vapor pressure, and may include acetaldehyde, acetylene, acetylene dichloride, actolane, acrylonitrile, benzene, 1, 3-butadiene, butane, 1-butene, 2-butene, carbon tetrachloride, chloroform, cyclohexane, 1,2-dichloroethane, diethylamine, dimethylamine, ethylene, formaldehyde, n-hexane, isopropyl alcohol, methanol, Methyl ethyl ketone, methylene chloride, MTBE, propylene, propylene oxide, 1,1,1-trichloroethane, trichloroethylene, gasoline, naphtha, crude oil, acetic acid, ethylbenzene, nitrobenzene, toluene, tetrachloroethylene , Xylene, styrene and the like.

The building material produced by the manufacturing method has excellent antimicrobial activity against strains containing Escherichia coli, and excellent for volatile organic compounds including formaldehyde and benzene, which are the causative agents of sick house syndrome, building syndrome, atopic dermatitis, etc. Has adsorption power Therefore, the building material according to the present invention can be usefully used as a building finishing material, through which can prevent the sick house syndrome, building syndrome and the like.

Hereinafter, the present invention will be described in detail with reference to Examples and Experimental Examples. However, the following examples and experimental examples are illustrative of the present invention, and the content of the present invention is not limited by the following examples and experimental examples.

Example  1. Preparation of Silver Nanoparticles

1-1. Dispersant  Verification of Stability of Silver Nanoparticles According to Different Types of Reducing Agents

In order to efficiently prepare the silver nanoparticles, the stability according to the type of dispersant and reducing agent was confirmed. The stability defined in this experiment means that the dispersed particles are agglomerated and do not grow into larger particles. The stability is defined as unstable that the particles become condensed and become large, causing the solution to become cloudy or dark.

More specifically, 50 ml of distilled water was added to a Pyrex beaker, and dispersants [PVP (Polyvinylpyrrolidinone), SDS (Sodium n-Dodecyl Sulfate) or Tween 20 (Polyoxyethylene Sorbitan Monooleate) were prepared according to the concentration (Table 1). ), The mixture was stirred at 50 to 60 ° C for 20 minutes to dissolve, and 0.5 ml of 4.4 mM silver nitrate (AgNO _{3 ;} 99.8%) was added thereto and stirred for 10 minutes. Thereafter, a 5 mM reducing agent [80% hydrazine hydrate or NaBH ₄ was injected in 0.1 ml increments until the silver particles were reduced to nanoparticles, ie, inherently transparent yellow. The silver nanoparticle solution prepared by selecting each one of a reducing agent and a dispersing agent was confirmed after 2 hours of manufacture. The results when using polyvinylpyrrolidinone (PVP), sodium n-Dodecyl Sulfate (SDS) or Tween20 (Polyoxyethylene Sorbitan Monooleate) as dispersants are shown in FIGS.

As shown in FIG. 1, when PVP (Polyvinylpyrrolidinone) was used as the dispersant and 80% hydrazine hydrate was used as the reducing agent, silver nanoparticles were stably dispersed when the PVP concentration was 15 wt%, thereby maintaining even light. At other concentrations, intergranular condensation occurred and darkened. NaBH ₄ as reducing agent In case of using (Sodium borohydride, powder), yellow opaque solution was obtained even when PVP concentration was 5 wt%, and all darkened at high concentration.

In addition, as shown in FIG. 2, when Tween 20 (Polyoxyethylene Sorbitan Monooleate) is used as a dispersant and 80% hydrazine hydrate is used as a reducing agent, even if a small amount of Tween 20 is added, the reduction reaction of the silver solution occurs rapidly, The change was severe and silver precipitated on the bottle surface when the concentration of Tween 20 exceeded 2 wt%. When NaBH ₄ was used as a reducing agent, the color became dark red when the concentration of Tween 20 was 1 wt%, and the silver nanoparticle solution became opaque and light in color when excessively injected.

In addition, as shown in FIG. 3, when SDS (Sodium n-Dodecyl Sulfate) was used as a dispersant and 80% hydrazine hydrate was used as a reducing agent, it became a turbid yellow-red solution when the concentration of SDS was 1 wt%. When the concentration of SDS was 1.5 wt% or more, the solution became turbid and silver precipitated on the bottle surface. When NaBH ₄ was used as a reducing agent, a very clear yellow solution was obtained when the concentration of SDS was 1 wt%, and the results confirmed that NaBH ₄ was a more effective reducing agent than hydrazine hydrate.

1-2. Dispersant  And silver nanoparticles according to the type of reducing agent Specifications  analysis

The size, shape and distribution of the silver nanoparticles prepared in Example 1-1 were analyzed using a particle size analyzer (Nanotrac150, Japan). The results are shown in Table 1 (reducing agent: NaBH ₄ ).

Dispersant Concentration ( wt  (%)) Diameter ( mean ), nm Appearance and distribution PVP 15 1900-3900 (2500) good 10 40-120 (55) good Tween 20 1.0 10-36 (13) good 1.5 10-36 (16) good 1.0 (w / hydrazine) 4-10 (5) good SDS 1.0 40-200 (56) Poor 1.5 100-800 (200) Poor 1.0 (w / hydrazine) 30-200 (70) Poor

As shown in Table 1, when the water-soluble polymer PVP (Polyvinyl Pyrrolidone; Povidone) was used at about 10% as a dispersant, a silver suspension having a uniform particle size distribution was generally obtained, but the particle size was micro level. In addition, when Tween20, a surfactant, was used as a dispersant, very small nanoparticles having an average size of 5 to 16 nm could be obtained. In addition, when SDS was used as a dispersant, the properties and distribution of silver nanoparticles were not uniform.

Therefore, in the following experiment, in order to prepare silver nanoparticles, 1 wt% of Tween20 as a dispersant and 5 mM NaBH ₄ as a reducing agent were used. Was used.

Example  2. Preparation of Bamboo Activated Carbon Coated with Silver Nanoparticles

The silver nanoparticles prepared in Example 1 were coated on a composition containing bamboo activated carbon to prepare a building material. More specifically, gypsum was fixed at 50% (weight ratio) and bamboo activated carbon was mixed with water and kneaded, and then, in Example 1, on a test specimen having a square shape (width x length x thickness (18 cm x 18 cm x 1.5 cm)). To prepare the silver nanoparticles, 1 wt% of Tween20 was used as a dispersant and 5 mM NaBH ₄ was used as a reducing agent. The size of the prepared silver nanoparticles was about 10 to 40 nm, and the concentration per surface area was about 8.3 mg / m ² .

Experimental Example  1. Antimicrobial test

In order to confirm the antimicrobial activity of the silver nanoparticle solution prepared in Example 1, Escherichia coli ( E. coli , KCTC 2441) was incubated in a diluted plate culture method in TSB (Tryptic Soy Broth, Becton, Dickinson & Company) medium. More specifically, 0.1 mL of silver nanoparticle solution, E. coli culture medium 0.3 mL, and 4 mL of TSB medium at 45 ° C. are added to each plate, and the mixture is hardened. The colonies of E. coli generated after 24 hours are counted according to the silver concentration. The degree of antibacterial was evaluated. Commercial silver powder was used as a control. The results are shown in Fig.

As shown in FIG. 4, when the silver nanoparticle solution of 475 ppm concentration of the present invention was mixed with E. coli and cultured, 99.5% of the antimicrobial activity was confirmed. In particular, the results were superior to the same amount of commercially available silver powder solutions (54% antimicrobial). Through the above results, it was confirmed that the bamboo activated carbon coated silver nanoparticles of the present invention has excellent antibacterial activity.

Experimental Example  2. Adsorption test of volatile organic compounds

In order to confirm the possibility of silver nanoparticles coated bamboo activated carbon as a building material, the adsorption of volatile organic compounds was examined. More specifically, bamboo activated carbon coated with silver nanoparticles was placed in a chamber having a volume of 160 m 3 (25 cm × 25 cm × 25 cm in height), and tested after sealing at room temperature and under conditions of minimal humidity change. As a control, bamboo activated carbon not coated with silver nanoparticles was used.

Adsorption analysis of Benzene was performed by injecting vaporized benzene (SIGAMA, USA) into a chamber containing silver nanoparticles coated bamboo activated carbon for 2 hours at 30 minute intervals. The solvent extraction method using a solid adsorption tube was used, and ORBO Tube-32 (SUPELCO, USA) was used. The pump used for measurement collected a total of 1 L at 1.5 L / min for 5 minutes using MP-Σ300 (SIBATA, Japan), which had a relatively small flow rate change before and after the measurement. The internal filling of the adsorbed solid adsorption tube was placed in a 3 ml vial, and then 1 ml of hydrogen disulfide (CS ₂ ) solution (99.9%, Sigma Aldrich) was injected into the stirrer (SWB-03, JEJO TECH) for 30 minutes. After stirring and extracting, 1 µl of the extracted solution was taken and measured by gas chromatography (GC-FID). Based on the CLP-BTEX-10X standard, a calibration curve was prepared at 0.1 ppm, 0.3 ppm, 0.5 ppm, and 1.0 ppm to calculate the concentration of benzene.

The adsorption amount of formaldehyde and benzene was calculated by the following equation.

[Equation 1]

Total suction sample volume (㎥) = (A _S -A _b ) * V / C _A

(C _A : concentration of formaldehyde or benzene in the indoor air sample (㎍ / ㎥),

A _S : Indoor air sample analysis result value (㎍ / ㎖),

A _b : DNPH background test value (㎍ / ㎖),

V: acetonitrile extraction volume (ml)

Adsorption test results for formaldehyde and benzene are shown in FIGS. 5 and 6, respectively.

As shown in FIG. 5, compared to bamboo activated carbon without silver nanoparticles coated (above FIG. 5), in the case of bamboo activated carbon coated silver nanoparticles of the present invention (under FIG. 5), 80% within 120 minutes. It was confirmed that the above high formaldehyde adsorption rate.

In addition, as shown in Figure 6, compared to the bamboo activated carbon uncoated silver nanoparticles (above Figure 6), in the case of the bamboo activated carbon coated silver nanoparticles of the present invention (under Figure 6), within 120 minutes It was confirmed that the high formaldehyde adsorption rate of more than 80%.

Through the above results, it was confirmed that the bamboo activated carbon coated with silver nanoparticles of the present invention has excellent adsorptivity to formaldehyde and benzene, which are representative volatile organic compounds, and thus can be usefully used as a building material.

Claims (9)

(a) preparing silver nanoparticles; And
(b) coating the silver nanoparticles of step (a) on a building composition comprising activated carbon; and a method for manufacturing building materials having improved antibacterial and adsorptive power to volatile organic compounds.
According to claim 1, wherein the silver nanoparticles in the step (a) using any one selected from the group consisting of PVP (Polyvinylpyrrolidinone), SDS (Sodium n-Dodecyl Sulfate) and Tween20 (Polyoxyethylene Sorbitan Monooleate), A method for producing a building material having improved adsorption capacity to antibacterial and volatile organic compounds, characterized in that it is prepared by a reduction precipitation method using a reducing agent of any one of hydrazine hydrate (Hydrazine hydrate) or NaBH ₄ .
According to claim 1, wherein the silver nanoparticles in step (a) using 0.5 to 1.5 wt% of Tween20 as a dispersant, 2 to 10 mM NaBH ₄ Method for producing a building material, characterized in that the production using the reducing agent, the adsorption power to the antibacterial and volatile organic compounds.
The method of claim 1, wherein the size of the silver nanoparticles in the step (a) is 2 to 100 nm, the antibacterial power and the adsorptive power to volatile organic compounds.
The method according to claim 1, wherein in the step (b) the activated carbon is made of oak, oyster oak, prunus oak, beech, oak, pine, bamboo, cherry, birch, birch, mulberry, chestnut, palm and sawdust A method for producing a building material, characterized in that at least one selected from the group, the antibacterial and adsorptive power to volatile organic compounds.
The method of claim 5, wherein the activated carbon is bamboo activated carbon, wherein the antibacterial and adsorptive power to volatile organic compounds is improved.
The method of claim 1, wherein the coating in step (b) comprises chemical vapor deposition, physical vapor deposition, chemical and electrochemical coatings, spraying, optical Characterized in that it is carried out using at least one method selected from the group consisting of optical coatings, spin coatings, dip coatings, bar coatings and UV coatings. The manufacturing method of the building material, which has improved antibacterial and adsorptive power to volatile organic compounds.
The method of claim 1, wherein the volatile organic compound is formaldehyde or benzene, wherein the antibacterial and adsorptive power to the volatile organic compound is improved.
A building material with improved antibacterial and adsorptive power to volatile organic compounds, comprising activated carbon coated with silver nanoparticles prepared by the method of any one of claims 1 to 8.

Images