KR102015819B1 - Hydrophobic Composition Containing Zinc Oxide Adsorption Layer And Preparation Method Thereof - Google Patents

Abstract

The present invention relates to a hydrophobic composite including a zinc oxide adsorption layer and a method for producing the composite, and the composite is prepared by hydrothermal synthesis, which enables easy manufacture even at a relatively low temperature, thereby improving processability and satisfying superhydrophobic characteristics. Excellent separation effect of solvent and water, excellent self-cleaning ability.

Description

Hydrophobic composite comprising zinc oxide adsorption layer and method for preparing the same {Hydrophobic Composition Containing Zinc Oxide Adsorption Layer And Preparation Method Thereof}

The present invention relates to a hydrophobic composite comprising a zinc oxide adsorption layer and a method for producing the same.

Various superhydrophobic materials are currently being developed to separate organic solvents and water, one of which is a PMIA / SiO ₂ membrane having a high density silicon nanofilament layer, which separates water from light oil (canola oil) and heavy oil (carbon tetrachloride CCl ₄ ). Do it. Most superhydrophobic filter papers have been developed through the deposition of colloids. Superhydrophobic copper mesh filters have been manufactured by hydrothermal methods to separate diesel from water, and recently, studies using hard substrates such as copper or stainless steel mesh have been conducted to prepare membranes.

Cotton fabrics, on the other hand, are well known for their porous, rough and flexible hydrophilic surfaces with very high absorption. Cotton fabrics are actually easier to design for applications than rigid substrates such as copper or stainless steel because of their soft, flexible, and lightweight properties, but cotton fabrics can be used to separate organic and water solvents because they can strongly absorb water and other organic solvents. There is no problem. Therefore, careful chemical modification is required to control the selectivity and wettability of cotton fabrics. According to the cassie-baxter state, which is based on the wettability of the fibers, water droplets do not fill the nanogrooves of the fiber surface to maintain superhydrophobicity, but form spheres and exist on the micro / nano structured fiber surface.

However, these hydrophobic materials on fabrics have time-consuming chemical treatments, are low in stability, selectivity and reusability, and have limited potential applications because of their large scale manufacturing limitations. Research using cotton fabrics or cotton fibers to the state is insignificant.

On the other hand, the use of zinc oxide (ZnO) as a functional material for making hydrophobic surfaces has been reported. Zinc oxide is well known for its biocompatibility, biodegradability and biostability, and it is expected that the control of wettability will be further improved due to the ease of surface structure development. Zinc oxide is also used for hexagonal crystal structure, wurtzize crystal structure, rod crystal structure, pillar crystal structure, wire crystal structure, belt crystal structure, flake crystal It has various types of structures such as structure, flower-like crystal structure. By using such well-known zinc oxide microstructures or nanostructures, the water contact angle (WCA) can be improved due to changes in original surface roughness and surface energy.

However, the conventional synthesis of zinc oxide has a problem that the processability is lowered in that it is carried out under high temperature conditions of 400 ℃ or more.

Therefore, there is a need for the development of a composite using cotton fabric and zinc oxide, which is easily manufactured even under relatively low temperature conditions, has a soft, flexible, superhydrophobic characteristic, and is capable of effectively separating an organic solvent and water.

Korean Patent Publication No. 10-2007-0035091.

SUMMARY OF THE INVENTION An object of the present invention is to provide a composite having excellent flexibility and light weight, having a superhydrophobic property, effectively separating an organic solvent and water, and being easy to self-clean, and a preparation method thereof.

The present invention to solve the above problems, fibers; And an adsorption layer comprising at least one zinc oxide particle on the surface of the fiber, wherein the zinc oxide particle has a plate shape and has an average diameter of 0.1 μm to 10 μm.

In addition, the present invention comprises the steps of immersing the fiber in a first liquid mixture containing a first zinc oxide precursor and an amine compound to impregnate the first zinc oxide precursor in the fiber; And heat treating the fiber impregnated with the first zinc oxide precursor in a second liquid mixture including the second zinc oxide precursor and the amine compound to form one or more zinc oxide particles on the surface of the fiber. It is plate-shaped and provides the manufacturing method of the composite characterized by the average diameter being 0.1 micrometer-10 micrometers.

The composite according to the present invention is prepared by the hydrothermal synthesis method can be easily manufactured even at a relatively low temperature to improve the processability, by satisfying the superhydrophobic characteristics, excellent separation effect of the organic solvent and water, and excellent self-cleaning ability.

Figure 1 schematically shows the manufacturing process of the composite according to Example 1.
Figure 2 is a FE-SEM picture of the cotton fabric (2-a) does not form a zinc oxide adsorption layer and the composite (2-b to 2-d) according to Example 1.
Figure 3 shows the XRD pattern of the original cotton and the composite (ZnO-cotton) according to Example 1 did not form a zinc oxide adsorption layer.
4 is a result of confocal analysis of a cotton fabric (ZnO-coated cotton fabric) according to Example 1 and an original cotton fabric that does not form a zinc oxide adsorption layer.
FIG. 5 is an XPS analysis result of a cotton fabric (ZnO-cotton) according to Example 1 and an original cotton without forming a zinc oxide adsorption layer.
6 is a result of measuring the static contact angle of the composite according to Example 1.
7 is a photograph showing the results of evaluating the self-cleaning properties of the methylene orange dye of the composite according to Example 1 and cotton fabric according to Comparative Example 1.
8 is a photograph showing the results of evaluating the self-cleaning characteristics of the composite according to Example 1 and the hydrophilic graphene oxide (GO) powder of the cotton fabric according to Comparative Example 1.
9 is a photograph showing the evaluation results of the hexane and water separation characteristics of the composite according to Example 1 and cotton fabric according to Comparative Example 1.
10 is a UV-Vis analysis result showing the separation efficiency according to the number of separation of the organic solvent and water of the composite according to Example 1.
11 is a graph showing the separation efficiency according to the number of separation of the organic solvent and water of the composite according to Example 1.

As the invention allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description.

However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

In the present invention, the terms "comprises" or "having" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

In addition, it is to be understood that the accompanying drawings in the present invention are shown to be enlarged or reduced for convenience of description.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings, and the same or corresponding components will be given the same reference numerals regardless of the reference numerals, and redundant description thereof will be omitted.

As a conventional superhydrophobic filter for separating water from an organic solvent, a separator using a hard substrate such as a copper or stainless steel mesh has been developed. A separator using a hard substrate such as a copper or stainless steel mesh is hard and flexible. There were problems that were difficult to apply to a variety of fields.

The present invention is to solve the above problems, and relates to a composite and a method of manufacturing the same that can be applied to a variety of fields while satisfying the superhydrophobic characteristics by adsorbing zinc oxide particles on a flexible and soft fiber.

Hereinafter, the composite according to the present invention will be described in detail.

The composite according to the present invention is a fiber; And an adsorption layer comprising one or more zinc oxide particles on the fiber surface, wherein the zinc oxide particles are plate-shaped and have an average diameter of 0.1 μm to 10 μm.

In the present invention, the 'adsorption layer' may mean a layer in which one or more zinc oxide particles are adsorbed on the surface of the fiber to cover the fiber surface by 80% or more. Specifically, the adsorption layer may have a structure in which zinc oxide particles are adsorbed at least 80%, 80% to 100%, 90% to 100%, or 95% to 99% based on the area of the fiber surface.

The zinc oxide particles may be adsorbed on the surface of the fiber in a plate shape as shown in FIG. Specifically, the average diameter of the zinc oxide particles is 0.2 μm to 8 μm, 0.3 μm to 5 μm, 0.4 μm to 3 μm, 0.5 μm to 2.8 μm, 0.55 μm to 2.5 μm, 0.6 μm to 2.3 μm, 0.65 μm to 2 Μm, or 0.8 μm to 1.5 μm. When the average diameter of the zinc oxide particles forming the zinc oxide adsorption layer is in the above range, it is easy for the composite to have superhydrophobic properties.

The fiber may include at least one selected from the group consisting of cellulose fiber, rayon fiber, nylon, aramid, polyester, and polypropylene, specifically, the fiber may be a cellulose fiber, and more specifically, cotton fiber. Can be. In addition, the fiber may be meant to encompass cotton, fabric or textiles.

The composite according to the invention may have a water contact angle of at least 150 °. In more detail, the water contact angle WCA may mean a static contact angle. As an example, when performed using a smart drop contact angle system using 5 μl of water droplets, the water contact angle is 150 ° to 170 °, 150.5 ° to 165 °, 150.8 ° to 160 °, 151 ° to 155 °, It can be 151 ± 3 ° or 151 °.

The composite according to the present invention may have a sliding angle of 10 ° or less. The sliding angle may mean a sliding contact angle (sliding CA). As an example, when performed using a smart drop contact angle system using 5 μl of water droplets, the sliding approach angles range from 1 ° to 10 °, 2 ° to 9.8 °, 3 ° to 9.5 °, 4 ° to 9.3 °, 5 ° to 9.2 °, 6 ° to 9.1 °, 9 ± 3 °, 9 ± 2 °, 9 ± 1 ° or 9 °.

In the composite according to the present invention, the static contact angle and the sliding contact angle satisfy the above range, thereby satisfying the superhydrophobic property.

delete

The adsorption layer according to the present invention may have an average thickness of 1 μm to 50 μm. Specifically, the average thickness of the adsorption layer is 1.5 μm to 40 μm, 2 μm to 35 μm, 2.5 μm to 30 μm, 3 μm to 25 μm, 3.5 μm to 20 μm, 4 μm to 15 μm, 4.5 μm to 10 μm. Micrometers, 5 μm to 8 μm, 10 μm to 30 μm, or 15 μm to 25 μm.

The complex may include peaks having energy bonds of 532 ± 1 eV, 290.5 ± 1 eV, and 284.0 ± 1 eV in X-ray photoelectron analysis, and may satisfy the following Equation 1.

[Equation 1]

0.1≤ CC / CO ≤ 1

In equation 1,

CC represents the area of the peak representing the binding energy between carbon (C) -hydrogen (H) or carbon (C) -carbon (C),

CO represents the area of the peak representing the binding energy between carbon (C) and oxygen (O).

In X-ray photoelectron analysis, a peak with an energy bond of 532 ± 1 eV may refer to a peak representing a binding energy between oxygen (O) and zinc (Zn), and a peak with an energy bond of 290.5 ± 1 eV is carbon. It may mean a peak representing the double bond energy between (C) -oxygen (O), the peak having an energy bond of 284.0 ± 1 eV is carbon (C) -hydrogen (H) or carbon (C) -carbon (C It may mean a peak representing the binding energy between the).

Equation 1 represents the peak energy representing the binding energy between carbon (C) and hydrogen (H) or carbon (C) and carbon (C) with respect to the area of the peak representing the double bond energy between carbon (C) and oxygen (O). The ratio of the area is shown. Specifically, Equation 1 is 0.15 ≦ CC / CO ≦ 0.95, 0.2 ≦ CC / CO ≦ 0.9, 0.25 ≦ CC / CO ≦ 0.85, 0.3 ≦ CC / CO ≦ 0.8, 0.35 ≦ CC / CO ≦ 0.75, 0.4 ≦ CC / CO ≦ 0.7, 0.45 ≦ CC / CO ≦ 0.65 or 0.5 ≦ CC / CO ≦ 0.6. The composite has an area of the peak representing the binding energy between carbon (C) -hydrogen (H) or carbon (C) -carbon (C) with respect to the area of the peak representing the binding energy between carbon (C) -oxygen (O). By satisfying the above range, the hydrophobic or superhydrophobic property can be satisfied.

As an example, the area (CC) of the peak representing the binding energy between carbon (C) -hydrogen (H) or carbon (C) -carbon (C) is 6% to 50%, 6.5% to 45%, 7% To 40%, 7.5% to 35%. 8% to 33%, 8.5% to 30%, 9% to 28%, 9.5% to 25%, 10% to 25.5%, 12% to 25%, 15% to 24.5%, 16% to 24%, 16.5% To 23.5%, 17% to 23%, 17.5% to 22.5%, 18% to 22.3%, 18.5% to 22%, 19% to 21.8%, 19.5% to 21.5%, or 20% to 21%. Further, the area CO of the peak representing the binding energy between carbon (C) and oxygen (O) is 5% to 72%, 8% to 70%, 10% to 65%, 12% to 62%, 15% to 60%, 18% to 58%, 20% to 55%, 25% to 52%, 28% to 50%, 30% to 48%, 33% to 47%, 35% to 45%, 38% to 43% Or 40% to 41%.

Hereinafter, the manufacturing method of the composite according to the present invention will be described in detail.

Method for producing a composite according to the present invention, the step of immersing the fiber in a first liquid mixture containing a first zinc oxide precursor and an amine compound impregnated with a first zinc oxide precursor in the fiber; And

Heat-treating the fiber impregnated with the first zinc oxide precursor in a second mixture containing the second zinc oxide precursor and the amine compound to form one or more zinc oxide particles on the surface of the fiber,

The zinc oxide particles are plate-shaped, and have an average diameter of 0.1 µm to 10 µm.

In the step of immersing the fiber in the first mixed solution containing the first zinc oxide precursor and the amine compound to impregnate the first zinc oxide precursor in the fiber, the first mixed solution has a amine compound of 50 based on 100 parts by weight of the first zinc oxide precursor solution To 150 parts by weight, 60 to 140 parts by weight, 70 to 130 parts by weight, 80 to 120 parts by weight, 90 to 110 parts by weight or may be mixed to 100 parts by weight. In addition, the first zinc oxide precursor may be mixed in a solvent at a concentration of 0.005M to 0.5M, 0.008M to 0.1M, 0.01M to 0.05M or 0.03M. Specifically, the first zinc oxide precursor solution may be 0.03M zinc acetate hydrate (Zn (CH ₃ COO) ₂ · 2H ₂ O).

The first mixed solution may be prepared by stirring for 1 to 5 hours at a temperature of 30 ℃ to 100 ℃, 40 ℃ to 80 ℃ or 50 ℃.

Further, after the step of impregnating the first zinc oxide precursor, the fibers impregnated with the first zinc oxide precursor before forming the zinc oxide particles are 5 to 5 at a temperature of 30 ℃ to 100 ℃, 40 ℃ to 80 ℃ or 50 ℃ Drying for 20 hours, 8 to 15 hours or 12 hours may be further included.

In the step of forming one or more zinc oxide particles on the fiber surface, the heat treatment temperature may be 80 ℃ to 120 ℃. Specifically, the heat treatment temperature may be 85 ° C to 115 ° C, 90 ° C to 110 ° C, 95 ° C to 105 ° C, or 100 ° C. In addition, the heat treatment time may be performed for 2 to 12 hours, 3 to 10 hours, 4 to 8 hours or 6 hours in the above temperature range.

Further, in the step of forming one or more zinc oxide particles on the fiber surface, the molar ratio of the second zinc oxide precursor and the amine compound may be 1: 5 to 5: 1, 1: 3 to 3: 1 or 1: 1. . In addition, the second mixed solution is based on 100 parts by weight of the second zinc oxide precursor solution and 1 to 100 parts by weight, 2 to 80 parts by weight, 3 to 70 parts by weight, 5 to 60 parts by weight, 8 to 55 parts by weight of the amine compound. , 10 to 50 parts by weight, 12 to 40 parts by weight, 15 to 35 parts by weight, 16 to 30 parts by weight, may be a mixture of 18 to 25 parts by weight or 20 parts by weight. Specifically, the second zinc oxide precursor solution may be 0.025M zinc nitrate hydrate (Zn (NO ₃ ) ₂ .6H ₂ O).

The pH of the first and second mixed solution may be 8 to 12. Specifically, the pH of the first and second mixed solution may be 8.5 to 11.5, 9 to 11 or 10 to 11. When the pH of the first and the second mixture is within the above range, the zinc oxide adsorbent layer is easily formed on the cotton fabric, and the prepared composite has superhydrophobic characteristics, thereby allowing the composite to exhibit excellent self-cleaning ability. .

The first and second zinc oxide precursors may be at least one selected from the group consisting of zinc acetate, zinc nitrate and zinc chloride, respectively. In the present invention, the first zinc oxide precursor and the second zinc oxide precursor may use the same precursor, or different ones may be used. As one example, the first zinc oxide precursor may use zinc acetate, and the second zinc oxide precursor may use zinc nitrate.

The amine compound is sodium hydroxide (NaOH), potassium hydroxide (KOH), ammonium hydroxide (NH ₄ OH), hexamethylenetetraamine (HMTA), lithium hydroxide (LiOH), rubidium hydroxide (RbOH), cesium hydroxide (CsOH), It may include one or more selected from the group consisting of calcium hydroxide (Ca (OH) ₂ ) and magnesium hydroxide (Mg (OH) ₂ ). Specifically, the amine compound may be used ammonium hydroxide (NH ₄ OH) or hexamethylenetetraamine (HMTA), the amine compound in each step may be used the same, may be different.

In the step of forming one or more zinc oxide particles on the fiber surface, amine methylenetetraamine (HMTA) may be used as the amine compound. The hexamethylenetetraamine allows the zinc oxide particles to be easily formed even at a relatively low temperature compared to a conventional temperature (400 ° C.). In addition, hexamethylenetetraamine can easily adjust the pH of the second mixed solution to the range according to the present invention to improve the uniformity of the growth structure of the zinc oxide particles.

After the step of forming at least one zinc oxide particles on the fiber surface, the step of drying for 30 to 100 hours, 15 to 28 hours or 24 hours at a temperature of 30 ℃ to 100 ℃, 40 ℃ to 80 ℃ or 50 ℃ It may further include.

In the method of manufacturing the composite, before the impregnation of the first zinc oxide precursor on the fiber, the method may further include the step of removing the impurities on the surface by sonicating the fiber. At this time, the step of removing impurities may be carried out by ultrasonication with a mixture of methanol and water, the execution time may be performed for 0.5 to 5 hours, 1 to 3 hours or 2 hours.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the following examples are merely to illustrate the invention, the content of the present invention is not limited by the following examples.

Example  One

1) Cotton fabric pretreatment step

A commercially available cotton fabric (product name: 100% cotton, manufactured by Daiso) was cut into 10 cm X 10 cm and sonicated with a mixture of 150 ml of methanol and 150 ml of water (methanol: water = 1: 1). Then, the cotton fabrics sonicated were washed three times or more with deionized water and then dried in an air oven at 50 ° C. for 24 hours.

2) zinc oxide precursor impregnation step

The pretreated cotton fabric was soaked in 200 ml of 0.03 M zinc acetate hydrate (Zn (CH ₃ COO) ₂ .2H ₂ O), and 20 ml of 25% ammonium hydroxide (NH ₄ OH) was slowly added dropwise while stirring the solution. Stirring continued for 3 hours. Then, the cotton fabric was taken out and dried for 12 hours at 50 ℃ in an air oven to prepare a cotton fabric impregnated with a zinc oxide precursor.

3) Zinc Oxide Particle Formation Step

200 ml of 0.025 M zinc nitrate hydrate (Zn (NO ₃ ) ₂ .6H ₂ O) and 200 ml of 0.025 M hexamethylenetetramine (HMTA) (400 ml solution with a molar ratio of 1: 1) was constantly stirred for 3 hours. One mixture was prepared. At this time, the pH of the mixture was maintained at 10 to 11. The prepared mixture was placed in a reactor (teflon lined stainless steel autoclave) and the cotton fabric impregnated with the zinc oxide precursor. Then, the reactor was heated to 100 ° C. for 6 hours, cooled to room temperature, the cotton fabric was taken out, washed three times or more with deionized water, and then dried in an air oven at 50 ° C. for 24 hours to be oxidized onto a fiber. A composite with an adsorption layer containing zinc particles was prepared. In this case, the fiber may mean a cotton fabric.

Figure 1 schematically shows the manufacturing process of the composite according to Example 1.

Figure 2 is a FE-SEM observation picture, Figure 2-a is a cotton fabric (Comparative Example 1) does not form a zinc oxide adsorption layer, Figure 2-b to 2-d is a composite prepared according to Example 1 Is the result. Referring to Figure 2-b to 2-d, it can be seen that the zinc oxide particles have a thin plate-like structure having a hexagonal slice form or an average diameter of 0.5 to 1.5㎛.

3 shows an XRD pattern of an original cotton without a zinc oxide adsorption layer and a composite (ZnO-cotton) according to Example 1 and a zinc oxide (ZnO) structure of the JCPDS standard. Referring to Figure 3, the composite according to the present invention (ZnO-cotton) it can be seen that the zinc oxide crystal phase is well formed on the surface of the cotton fabric. The peaks at 2θ = 14.98 °, 16.89 ° and 22.86 ° correspond to the peaks of cellulose which is the main component of the cotton fabric. The remaining relative peaks correspond to the hexagonal structure of ZnO as compared to the ZnO structure of the JCPDS standard (Jointed Committee of the Powder Diffraction Standard-Card No. 36-1451), 2θ = 32.09 °, 34.63 °, 36.44 °, 47.60 °, 56.76 Peaks detected at °, 63.18 °, 66.44 °, 68.20 °, 69.18 °, 72.83 °, and 76.9 l ° are (100), (002), (101), (102), (110), (103), ( 200, 112, 201, 004, and 202. In addition, no impurities were found in the XRD pattern, indicating that a high purity ZnO crystal phase was formed on the surface of the cotton fabric.

4 is a confocal analysis result of a cotton fabric (ZnO-coated cotton fabric) according to Example 1 and an original cotton fabric (ZnO-coated cotton fabric) without forming a zinc oxide adsorption layer, and did not form a zinc oxide adsorption layer. In the case of the cotton fabric, the surface roughness (Ra) indicating the average roughness was 0.85 and the average thickness was 91.1 µm, but the surface roughness (Ra) was 2.42 in the composite according to Example 1, and the average thickness was 105.4 µm. It was confirmed that the surface roughness and the average thickness were effectively increased by forming the zinc oxide adsorption layer. Such surface roughness values allow the composite to have hydrophobic properties.

Table 1 and FIG. 5 shows elemental analysis results of X-ray photoelectron spectroscopy (XPS) of a cotton fabric (ZnO-cotton) according to Example 1 and a cotton fabric that does not form a zinc oxide adsorption layer. Looking at -b, the zinc oxide peak was observed in the composite (ZnO-cotton) according to Example 1, and in Fig. 5-c, OH bond was observed in the case of the original cotton which did not form a zinc oxide adsorption layer. Although the peak area of 45.5%, the composite according to Example 1 (ZnO-cotton) it can be seen that the peak area of the OH bond is reduced to 35.9% to exhibit a hydrophobic property. Referring to FIG. 5-d, the peak area of the CH / CC bond was 5.7% in the case of the original cotton which did not form the zinc oxide adsorption layer, but the CH / CC bond was used in the composite according to Example 1 The peak area of is increased to 20.9%. Based on electronegativity, C-H / C-C bonds are known as nonpolar bonds, and C = O and C-O bonds are known as polar bonds. Improved CH / CC bonds and reduced C = O and CO bonds result in hydrophobic and non-polar characteristics of the cotton fabric on which the zinc oxide adsorption layer is formed, so that water passes through the surface of the cotton fabric on which the zinc oxide adsorption layer is formed. You will not be able to. In addition, the surface of the cotton fabric on which the zinc oxide adsorption layer is formed may facilitate the penetration of a nonpolar solution such as hexane, toluene, chloroform, and the like. Therefore, the composite according to the present invention can be easily applied to the effective separation of water and organic solvent from a mixture of nonpolar organic solvent and water.

Element Type of bonding Binding energy (eV) Peak area (%) Original cotton ZnO-cotton Original cotton ZnO-cotton O1s O-H 537.2 537.6 45.5 35.9 O-C 535.8 535.9 35.3 30.0 O = C 534.2 534.4 19.2 20.1 O-Zn Not detected 532.0 0 14.0 C1s C = O 290.4 290.6 74.7 40.4 C-O 287.7 287.4 19.6 38.7 C-H / C-C 284.5 284.3 5.7 20.9

Comparative example  One

The same cotton fabric as used in Example 1 was cut into 10 cm X 10 cm to prepare.

Comparative example  2

It was prepared in the same manner as in Example 1 except that triethylamine was used instead of ammonium hydroxide (NH ₄ OH).

Comparative example  3

A pH of a mixture of zinc nitrate hydrate (Zn (NO ₃ ) ₂ .6H ₂ O) 0.025M and hexamethylenetetramine (HMTA) 0.025M was prepared in the same manner as in Example 1.

Experimental Example  One: Superhydrophobic  Property evaluation

In order to confirm the superhydrophobic properties of the composite and cotton fabric according to Example 1 and Comparative Examples 1 to 3, the water contact angle (WCA) was measured. The water contact angle measurement was performed using a smart drop contact angle system using 5 μl of water droplets, and the static contact angle and sliding angle were measured, respectively. At this time, when the conditions of the static contact angle of 150 ° or more and the sliding angle of 10 ° or less are satisfied, it shows superhydrophobic characteristics. The static contact angle measured the water contact angle when each composite and the cotton fabric is horizontal, the sliding angle was measured in 1 ° to 10 ° while changing in units of 1 °, the sliding angle of the water droplets was measured. As a result, referring to Table 2 below, the static contact angle of the composite according to Example 1 was found to be 151 ± 3 °, and the sliding angle was 9 ± 1 °, indicating superhydrophobic characteristics. 6 is a photograph of measuring the static contact angle of the composite according to Example 1 6-b is water, 6-c is a methylene orange dye mixture, 6-d is a photograph showing the water contact angle for the coffee mixture. Accordingly, the composite according to the present invention was found to exhibit superhydrophobic properties for various water mixtures. On the other hand, in the cotton fabric according to Comparative Example 1 in which the zinc oxide adsorption layer was not formed, water droplets were immediately absorbed and thus the water contact angle could not be measured. In the composite according to Comparative Example 2, the static contact angle was found to be 155 ± 2 °, but the sliding angle was 15 ± 3 °, which was larger than 10 °, and the composite according to Comparative Example 3 was also shown to have a static contact angle of 153 ± 2 °. However, the sliding angle was 17 ± 2 °, which was larger than 10 °, which did not satisfy the superhydrophobic condition.

division Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Static contact angle (°) 151 ± 3 Not measurable 155 ± 2 153 ± 2 Sliding angle (°) 9 ± 1 15 ± 3 17 ± 2

Experimental Example  2: self-cleaning characteristic evaluation

In order to evaluate the self-cleaning properties of the composite according to the present invention, the degree of contamination to methylene orange dye and hydrophilic graphene oxide (GO) was confirmed.

First, the methylene orange dye was immersed in water mixed with a concentration of 5x10 ^-4 M for 3 seconds in a composite according to Example 1 and a cotton fabric in Comparative Example 1, and then removed and dried. The degree of pigmentation was visually observed. The results are shown in Figure 7, Figure 7-a as a result of the cotton fabric according to Comparative Example 1 it can be seen that the number of the immersion methyl orange dye is colored a yellow color as the number of times from one to four times. 7-b was confirmed that the dye is almost no color even after immersion four times as a result of the composite according to Example 1.

Second, after applying the hydrophilic graphene oxide (GO) powder to the cotton fabric in the composite according to Example 1 and Comparative Example 1 was evaluated for self-cleaning ability when water is dropped. The results are shown in FIG. When the cotton fabric according to Comparative Example 1 was sprayed with water after applying the hydrophilic graphene oxide powder as shown in Fig. 8-A, water was quickly absorbed into the cotton fabric, so that the washing of the graphene oxide powder was not performed well. Can be. On the other hand, when the composite according to Example 1 is sprayed with water after applying the hydrophilic graphene oxide powder as shown in Figure 8-b, it can be seen that the water droplets remove the graphene oxide powder.

Therefore, the composite according to the present invention, it was found that the self-cleaning properties are significantly improved by forming the zinc oxide adsorption layer according to the present invention on the cotton fabric.

Experimental Example  3: Evaluation of Water Separation Characteristics

In order to evaluate the nucleic acid and water separation characteristics of the complex according to the present invention, 20 ml of water and 20 ml of hexane in a measuring cylinder were mixed with the complex according to Example 1 and the cotton fabric according to Comparative Example 1, and then the water-hexane mixture was mixed. The separation properties of hexane and water were evaluated by passing over the composite and cotton fabrics.

Hexane and water separation characteristics evaluation was performed in the same manner as shown in Figure 9-a, wherein water was used by mixing a methylene orange dye to easily confirm that the separation with hexane. As a result, the cotton fabric according to Comparative Example 1 could not selectively separate hexane and water as shown in Fig. 9-b, so that the methylene orange dye mixture passed under the cotton fabric as it is, and the solution contained in the beaker was confirmed to have an orange color. Could. On the other hand, the composite according to Example 1 effectively separates hexane and water as shown in Figure 9-c, the water stained with methylene orange dye remains in the complex on the funnel, but only hexane is separated and transparent in the beaker below You can see that.

Therefore, it was confirmed that the complex according to the present invention can effectively separate hexane and water.

10 and 11 are graphs showing the separation efficiency of the composite according to Example 1. 10 is a result of UV-Vis analysis of water after separating hexane and water 1 to 9 times by the above method, and no peaks of new impurities were observed except for the peak of methylene orange dye even after 9 times of separation. 11 is a graph showing the separation efficiency of water after separating the hexane and water 1 to 9 times by the above method, the separation efficiency of the first cycle was 99.86%, even if the ninth cycle proceeds to 97.69 The results were high as%. Therefore, the composite according to the present invention was confirmed that when the separation of the organic solvent (hexane) and water once to 9 times, the separation efficiency can maintain 95% to 99.99%, specifically 97% to 99.9%.

Therefore, it can be seen that the composite according to the present invention can effectively separate the organic solvent and water.

Claims (13)

fiber; And an adsorption layer comprising one or more zinc oxide particles formed on the fiber surface,
The zinc oxide particles are plate-like, the average diameter of 0.1㎛ 10㎛,
Zinc oxide particles are adsorbed on the surface of the fiber, covering over 80% of the surface of the fiber,
The composite has a water contact angle of more than 150 °
The composite is characterized in that the sliding angle is less than 10 °.
The method of claim 1,
The fiber is characterized in that it comprises at least one member selected from the group consisting of cellulose fibers, rayon fibers, nylon, aramid, polyester and polypropylene.
delete delete delete The method of claim 1,
The adsorption layer is a composite, characterized in that the average thickness is 1㎛ to 50㎛.
The method of claim 1,
The complex includes peaks having energy bonds of 532 ± 1 eV, 290.5 ± 1 eV and 284.0 ± 1 eV when X-ray photoelectron analysis, and satisfy the conditions of the following formula 1:
[Equation 1]
0.1≤ CC / CO ≤ 1
In equation 1,
CC represents the area of the peak representing the binding energy between carbon (C) -hydrogen (H) or carbon (C) -carbon (C),
CO represents the area of the peak representing the binding energy between carbon (C) and oxygen (O).
Impregnating the fibers in a first mixed solution including a first zinc oxide precursor and an amine compound to impregnate the first zinc oxide precursor in the fibers; And
Heat-treating the fiber impregnated with the first zinc oxide precursor in a second mixture containing the second zinc oxide precursor and the amine compound to form one or more zinc oxide particles on the surface of the fiber,
The zinc oxide particles are plate-shaped, the average diameter is 0.1㎛ to 10㎛ manufacturing method of the composite according to claim 1 characterized in that.
The method of claim 8,
The heat treatment temperature is 80 ℃ to 120 ℃ manufacturing method of the composite, characterized in that.
The method of claim 8,
The first and the second liquid mixture has a pH of 8 to 12 method for producing a composite.
The method of claim 8,
The first and second zinc oxide precursors are each one or more selected from the group consisting of zinc acetate, zinc nitrate and zinc chloride.
delete The method of claim 8,
Prior to impregnating the fiber with a first zinc oxide precursor,
Ultrasonically treating the fibers to remove the surface impurities manufacturing method of the composite.

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