KR20190049382A - Composite based melamine resin, and oil-water separating materials - Google Patents

Abstract

The present invention relates to oil-water separating materials and a method for producing the same. The oil-water separating materials include a composite in which a zinc oxide particle layer aggregated randomly in a radial manner to form a micro-nanostructure on a melamine resin matrix having a porous, foamed structure; and a fatty acid layer are sequentially formed, and thus are not only excellent in durability, but also have an advantage that the average BET specific surface area is large and oil-water separation efficiency is excellent by being lipophilic, superhydrophobic, and super-water repellent. Therefore, the materials can be effectively used as absorption-type, oil-water separating materials used for large-scale oil-water separation such as oil removal from the ocean.

Description

TECHNICAL FIELD [0001] The present invention relates to a melamine resin-based composite, and a melamine resin-based composite and an oil-

The present invention relates to a melamine resin-based composite, and a material for water-diluting comprising the same.

Recently, due to environmental problems, attention has been paid to oil-water separating materials for removing pollutants present in the water. Research on the high performance and application of separation materials and diversification of use fields have been actively carried out, .

Conventional water-oil separation methods commonly used include separation of gravity and adsorption. Of these, the gravity separation method is simple in structure due to a small mechanical operation part, and consumables to be replaced as a filter are not used. There are advantages to be able to. However, since the efficiency of separating the oil is low and the water (H ₂ O) content in the separated and discharged oil is high, it is difficult to recycle the oil and the amount of water is increased by mixing with water, there is a problem. In addition, since the oil-water separating capacity is not large, oil can not be effectively separated in a short period of time in the case of a wide range of contamination such as oil leaking into the sea or river.

As an alternative to this, in-depth research is underway on the development of optimal manufacturing processes for the characterization of the separating materials used in the adsorption process and on the technology for producing the separating materials with high functionality by the surface treatment technique.

For example, the plasma surface treatment technique has been developed to improve the performance of a material by changing the surface of a polymer material used as a disk or a filter in an adsorption method. However, since the technologies developed so far require a surface treatment process such as a plasma treatment, the production cost of the material is high, and the performance required for oil separation, for example, properties such as adhesion angle indicating the water affinity of the separation material There is a limit to the degree of improvement.

As a result, it is possible to produce a large amount of water in a short time, and it is easy to manufacture materials and to carry out a large-scale oil-water separating work, is economical, has excellent performance such as water affinity for water separation, Development of a separating material is required.

Korean Registered Patent No. 10-0786678

An object of the present invention is to provide a separating material which is easy to manufacture and economically has a large area oil-water separating operation, excellent in performance such as water affinity for oil-water separation, and excellent in oil-water separation efficiency.

In order to solve the above problems,

The present invention, in one embodiment,

A melamine resin matrix having a spongy porous structure;

A zinc oxide particle layer surrounding the matrix surface; And

And a fatty acid layer having 10 to 30 carbon atoms surrounding the zinc oxide particle layer,

The zinc oxide particle layer provides a composite in which two or more zinc oxide particles are randomly radially aggregated based on any one point of the matrix surface.

In addition, the present invention, in one embodiment,

Immersing a melamine resin matrix having a sponge-like porous structure in a zinc oxide precursor solution and irradiating microwave to form a zinc oxide particle layer on the surface of the matrix; And

Immersing a melamine resin matrix having a zinc oxide particle layer on its surface in a solution of 10 to 30 carbon atoms in which a fatty acid is dissolved to form a fatty acid layer surrounding the zinc oxide particle layer,

Wherein the zinc oxide particle layer has a structure in which two or more zinc oxide particles are aggregated randomly in a radial manner based on any one point of the surface of the matrix.

Further, in one embodiment, the present invention provides a material for oil-water separation comprising the composite.

Since the composite according to the present invention is manufactured through microwave irradiation, the manufacturing process is simple, and two or more zinc oxide particles are aggregated in a random radial manner based on any one point of the surface of the melamine resin matrix having a porous structure on the sea surface A zinc oxide particle layer and a fatty acid layer forming a micro-nano structure are sequentially formed to provide excellent durability and a wide average BET specific surface area, and exhibits lipophilic property, super hydrophobic property and super water repellency, And can be usefully used as a material for oil-adsorbing oil-and-water separation used for large-scale oil-water separation such as removal.

1 is an image showing a result of SEM analysis of (a) melamine sponge as a non-treated member and (b) the composite prepared in Example 1.
FIG. 2 is a graph showing X-ray photoelectron spectroscopy (XPS) results of the melamine sponge as a non-treated member and the composite prepared in Example 1. FIG.
FIG. 3 is a graph showing Fourier transform-infrared spectroscopy (IR) results of a melamine sponge as a non-treated group and the composite prepared in Example 1. FIG.
4 is a graph showing the measurement results of the water contact angle of the composite prepared in each of the untreated group and the example 1 and the comparative example 1. FIG.
FIG. 5 is a graph showing oil-water separation efficiency according to the kind of oil of the composite prepared in Example 1. FIG.
FIG. 6 is a graph showing oil separation efficiency according to the number of times of reuse of the composite prepared in Example 1. FIG.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail.

It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

In the present invention, the terms " comprising " or " having ", and the like, specify that the presence of a feature, a number, a step, an operation, an element, a component, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a material for water softening and a method for producing the same.

Recently, due to environmental problems, attention has been paid to oil-water separating materials for removing pollutants present in the water. Research on the high performance and application of separation materials and diversification of use fields have been actively carried out, .

Conventional water-oil separation methods commonly used include separation of specific gravity and adsorption, and development of an optimum manufacturing process for the characteristics of the separation material used in the adsorption system and separation of the high- In-depth research on material manufacturing technology is under way. For example, the plasma surface treatment technique has been developed to improve the performance of a material by changing the surface of a polymer material used as a disk or a filter in an adsorption method. However, since the technologies developed so far require a surface treatment process such as a plasma treatment, the production cost of the material is high, and the performance required for oil separation, for example, properties such as adhesion angle indicating the water affinity of the separation material There is a limit to the degree of improvement.

Accordingly, the present invention provides a composite based on a melamine resin, and a material for water softening including the same.

Since the composite according to the present invention is manufactured through microwave irradiation, the manufacturing process is simple, and two or more zinc oxide particles are aggregated in a random radial manner based on any one point of the surface of the melamine resin matrix having a porous structure on the sea surface A zinc oxide particle layer and a fatty acid layer forming a micro-nano structure are sequentially formed to provide excellent durability and a wide average BET specific surface area, and exhibits lipophilic property, super hydrophobic property and super water repellency, It can be usefully used as a material for the separation of water for use in adsorption, which is used for large-scale oil-water separation.

Hereinafter, the present invention will be described in more detail.

Complex

The present invention, in one embodiment, provides a melamine resin-based composite.

In detail, the composite according to the present invention comprises a melamine resin matrix having a porous structure on the surface of the sea, and surrounds the melamine resin matrix surface, wherein two or more zinc oxide particles are aggregated in a random radial manner on the basis of any one point of the surface of the matrix. And a fatty acid layer surrounding the surface of the zinc oxide particle layer.

The present invention includes a sponge-like melamine resin matrix, such as a melamine sponge, which has a low manufacturing cost and is economical and has a high hardness, and the melamine resin matrix may include open pores. Specifically, the melamine resin matrix may include open pores having an average size or diameter of 50 탆 to 500 탆, and more specifically, 50 탆 to 400 탆, 50 탆 to 300 탆, 50 탆 to 200 탆, 50 탆 100 to 200, 200 to 300, 300 to 400, 400 to 500, 300 to 500, 250 to 500, 80 to 180, or 100 to 160 Lt; / RTI > The present invention includes a melamine resin matrix having a sponge having open pores having a diameter as described above, so that a high elasticity of the composite can be realized, thereby exhibiting an excellent durability.

As an example, when the composite is compressed at 50% or 70% strain at room temperature (21 ± 2 ° C), the stress applied thereto is 0.0003 to 0.0004 MPa, specifically 0.0003 to 0.00039 MPa, 0.0003 to 0.00037 MPa, 0.0003 to 0.00035 MPa, 0.0003 to 0.00032 MPa, and 0.00035 to 0.00038 MPa. This is equivalent to a melamine resin sponge which is commercially available in the prior art, and the composite according to the present invention has excellent elasticity and high durability.

The composite according to the present invention also includes a zinc oxide particle layer surrounding the melamine resin matrix surface and having a structure in which two or more zinc oxide particles are randomly radially aggregated based on any one point of the matrix surface.

The average length of the zinc oxide particles may be 1 to 10 탆 and the average thickness may be 0.1 to 2 탆. More specifically, the average length may be 1 to 8 탆, 1 to 6 탆, 4 탆 to 10 탆, 4 탆 to 10 탆, 6 탆 to 10 탆, 8 탆 to 10 탆, 4 탆 to 8, 3 탆 to 6 탆, 4 탆 to 5 탆, And the average thickness may be 0.1 탆 to 1.5 탆, 0.1 탆 to 1 탆, 0.5 탆 to 1.5 탆, or 0.8 탆 to 1.3 탆. In addition, the ratio of the average thickness (D) to the average length (L) of the zinc oxide particles may be 3 to 6, specifically 3.5 to 5.5, 4 to 5, or 4.1 to 4.7.

Since zinc oxide particles can agglomerate randomly in the aggregation at the surface of the melamine resin matrix by controlling the average length and the average thickness of the zinc oxide particles having hydrophobicity in the above range, the zinc oxide particles grow perpendicularly to the surface of the matrix Surface roughness and average BET specific surface area can be large compared to zinc oxide particle layer. Conventionally, zinc oxide particles are known to have high affinity to water, including hydroxyl groups (-OH) on their surfaces. However, the composite of the present invention has a large surface roughness and surface area through the random radial agglomeration of the zinc oxide particles on the surface of the melamine resin matrix, thereby increasing the water repellency by inducing the formation of more air pockets on the surface.

Further, the complex according to the present invention comprises a fatty acid layer surrounding the zinc oxide particle layer, wherein the fatty acid may comprise a fatty acid having from 10 to 30 carbon atoms. Specifically, the fatty acid layer is composed of capric acid having 10 carbon atoms, lauric acid having 12 carbon atoms, myristic acid having 14 carbon atoms, palmitic acid having 16 carbon atoms, stearic acid having 18 carbon atoms, arachic acid having 20 carbon atoms and behenic acid having 22 carbon atoms , And the like. For example, the composite may comprise stearic acid in the fatty acid layer surrounding the zinc oxide particle layer.

In addition, the average thickness of the fatty acid layer may be such that the surface energy can be sufficiently lowered without lowering the surface roughness of the composite. Specifically, the average thickness of the fatty acid layer may be 20 nm or less, specifically 15 nm or less, 10 nm or less, 0.5 nm to 10 nm or 2 nm to 8 nm.

In general, the melamine resin matrix has a high affinity to water, so that it can not measure the contact angle because it absorbs all of the water contacted to the surface during the measurement of the static water contact angle. However, the composite according to the present invention includes a zinc oxide particle layer having a structure in which two or more zinc oxide particles are randomly radially aggregated based on an arbitrary point on the surface of the melamine resin matrix, thereby maximizing the surface roughness, By surrounding the surface of the zinc oxide particle layer with a fatty acid having a low carbon number of 10 to 30, both the superhydrophobic and lipophilic properties can be realized on the surface of the melamine resin matrix.

As an example, the composite may have a static water contact angle of 150 ° or more, more specifically 150 ° to 170 °, 155 ° to 165 °, 157 ° Deg.] To 165 [deg.] Or 157 [deg.] To 162 [deg.].

As another example, the composite may have a sliding water contact angle and a shedding water contact angle, each of which exhibits water repellency, of 15 ° or less, and more specifically, the average water slip The angle and the average water flow angle are in the range of 5 to 15 degrees, 5 to 13 degrees, 5 to 11 degrees, 5 to 10 degrees, 7 to 15 degrees, 8 to 13 degrees, 8 to 10 degrees, 9 DEG to 11 DEG.

As another example, the composite has a very high affinity for organic materials such as oil, so that it absorbs all of the oil contacted to the surface during the measurement of the average static oil contact angle, And in this case the average static oil contact angle can be regarded as 0 °.

For example, the composite according to the present invention may have an average static water contact angle of 159 ± 1 °, an average water slip angle and an average water flow angle of 10 ± 0.5 ° and 9 ± 0.5 °, respectively.

The composite according to the present invention is characterized in that a zinc oxide particle layer and a fatty acid layer are sequentially formed on a melamine resin matrix having a spongy porous structure to form a micro-nano structure, Lipophilic property and super water repellency, and is excellent in oil separation efficiency, so that it can be usefully used as an adsorption type water separation material used for large-scale oil separation such as oil removal from the ocean.

Method of making composite

In addition, the present invention, in one embodiment,

Immersing a melamine resin matrix having a sponge-like porous structure in a zinc oxide precursor solution and irradiating microwave to form a zinc oxide particle layer on the surface of the matrix; And

Immersing a melamine resin matrix having a zinc oxide particle layer on its surface in a solution of 10 to 30 carbon atoms in which a fatty acid is dissolved to form a fatty acid layer surrounding the zinc oxide particle layer,

Wherein the zinc oxide particle layer has a structure in which two or more zinc oxide particles are aggregated randomly in a radial manner based on any one point of the surface of the matrix.

The method for producing a composite according to the present invention comprises the steps of forming a randomly radially aggregated zinc oxide particle layer on the surface of a melamine resin matrix having a porous structure on the sea surface and coating a zinc oxide particle layer formed on the surface with a fatty acid to form a fatty acid layer .

Specifically, the step of forming the zinc oxide particle layer on the surface of the melamine resin matrix comprises immersing the melamine resin matrix in a zinc oxide precursor solution having a pH of 9 to 12 and containing a predetermined concentration of zinc ions (Zn ^{2 +} ), Zinc oxide particles on the melamine resin matrix can form a zinc oxide particle layer aggregated in a random radial shape having a large surface roughness.

In this case, the zinc oxide precursor solution of zinc acetate (Zn (OAc) _2), zinc chloride (ZnCl _2), zinc hydroxide (Zn (OH) _2), zinc nitrate (Zn (NO _{3) 2),} such as the zinc oxide precursor Is dissolved in a concentration of 0.1 M to 2 M, ammonia water is added to the aqueous solution to adjust pH to 9 to 12, and 0.1 M to 2 M, specifically 0.1 M to 1.5 M, 0.1 M to 1.2 M, 0.1 M to 1 M, 0.1 M to 0.6 M, 0.1 M to 0.5 M, 0.1 M to 0.3 M, 0.3 M to 0.5 M, 0.4 M to 0.7 M, 0.5 M to 1 M, 0.7 M to 1 M, 1 M to 1.5 M, 0.8 M to 1.2M or a concentration of zinc ions (Zn ^< ^{2 + &} gt ^; ) of 0.15M to 0.25M may be dissolved. The present invention can control the concentration of zinc ions (Zn ^{2 +} ) present in the zinc oxide precursor solution within the above range to form zinc oxide particles uniformly on the surface of the melamine resin matrix, The shape and growth direction of the zinc oxide particles can be controlled and the agglomerate shape of the zinc oxide particles can be controlled in a random radial manner, thereby maximizing the surface roughness of the composite.

In addition, the output of the microwave may be 1,000 W to 1,500 W, specifically 1,000 W to 1,500 W, 1,050 W to 1,300 W, or 1,080 W to 1,200 W, the frequency of the microwave may be 2,000 MHz to 3,000 MHz, May be from 2,200 MHz to 2,600 MHz or from 2,400 MHz to 2,500 MHz.

In addition, the microwave irradiation may include an irradiation step of microwave-treating the melamine resin matrix; And an aging step of leaving the microwave irradiated melamine resin matrix, and the irradiating step and the aging step may be repeated n times (integer of n < = 10).

The execution time of the irradiation step may be 10 to 100 seconds, specifically 10 to 80 seconds, 20 to 80 minutes, 30 to 70 seconds, 40 to 80 seconds, 50 to 70 seconds, 30 to 100 seconds, 50 to 100 Sec, 70 to 100 sec, or 55 to 65 sec.

Also, the aging time is 1 to 60 seconds, specifically 1 to 50 seconds, 1 to 40 seconds, 5 to 40 seconds. 10 to 40 seconds, 20 to 40 seconds, 30 to 60 seconds, 50 to 60 seconds, or 25 to 35 seconds.

As one example, the microwave irradiation may include an irradiating step of microwave-treating the melamine resin matrix for 57 to 62 seconds; And an aging step in which the microwave irradiated melamine resin matrix is left for 27 to 32 seconds, and the irradiation step and the aging step may be repeated twice.

The present invention is characterized in that the temperature of the zinc oxide precursor solution and the melamine resin matrix can be maintained uniformly by repeating micro-irradiation and aging for a specific time in the melamine resin matrix immersed in the zinc oxide precursor solution, The shape and growth direction of the zinc oxide particles can be controlled, and the zinc oxide particles can be controlled in a random radial manner, so that the surface roughness of the composite can be maximized.

Further, in the step of coating the formed zinc oxide particle layer with a fatty acid to form a fatty acid layer, the melamine resin matrix having the zinc oxide particle layer formed on its surface is immersed in a fatty acid solution having a concentration of 0.005M to 0.1M for 1 minute to 10 minutes, Layer can be formed.

The fatty acid may include a fatty acid having 10 to 30 carbon atoms. Specifically, the fatty acid layer is composed of capric acid having 10 carbon atoms, lauric acid having 12 carbon atoms, myristic acid having 14 carbon atoms, palmitic acid having 16 carbon atoms, stearic acid having 18 carbon atoms, arachic acid having 20 carbon atoms and behenic acid having 22 carbon atoms , And the like. For example, the composite may comprise stearic acid in the fatty acid layer surrounding the zinc oxide particle layer.

In addition, the average thickness of the fatty acid layer may be such that the surface energy can be sufficiently lowered without lowering the surface roughness of the composite. Specifically, the average thickness of the fatty acid layer may be 15 nm or less, 10 nm or less, 0.5 nm to 10 nm or 2 nm to 8 nm, and the average thickness may be determined by the time and / or concentration of the melamine resin matrix immersed in the fatty acid solution Lt; / RTI >

Materials for oil-water separation

Furthermore, the present invention provides, in one embodiment, a material for water drainage comprising a composite according to the present invention.

The material for water-splitting according to the present invention is formed by sequentially forming a zinc oxide particle layer and a fatty acid layer which are aggregated randomly in a radial pattern on a melamine resin matrix having a porous structure on the sea surface to form a micro-nano structure and thus have excellent durability, The composite of the present invention showing wide, lipophilic, super hydrophobic, and super water repellent properties can be reused and excellent in oil separation efficiency.

Specifically, a melamine sponge having a porous structure used as a general water-dispersible material can realize super-hydrophobicity through various surface treatments, but does not exhibit water repellency. Therefore, when oil is spilled on fresh water and / or oceans, It absorbs a considerable amount of water together and is present in the water. However, the oil-water separating material according to the present invention exhibits lipophilicity as well as lipophilic property and super-hydrophobic property, so that when oil flows out into freshwater and / or oceans, only the oil floating on the water surface is selectively absorbed, There is an advantage that the efficiency is excellent and the treatment after the water separation is easy.

As one example, the oil-water separating material exhibits lipophilic, super-hydrophobic, and super-water-repellent properties including the composite according to the present invention. The above material is fixed to a reactor, and methanol, methanol, n-hexane, vacuum oil, gasoline, canola oil or diesel and water are mixed at a ratio of 1: 1 volume ratio, the oil is absorbed and passed through the material, but the water remains on the surface without being absorbed by the material, and the separation efficiency of the separated water is determined by the volume of water contained in the mixed solution Of 95% or more, specifically, 97% or more.

As another example, the oil-water separating material includes a composite according to the present invention and is excellent in durability, so that it can be used in a variety of fields such as methanol, n-hexame, vacuum oil, gasoline, When oil water separation is performed 50 times for a mixed solution of canola oil or diesel and water in a volume ratio of 1: 1, separation efficiencies of 60% or more are exhibited for all the oil components during 30 times of oil separation, When the glass is separated by 50 times, it can exhibit a separation efficiency of 80% or more with respect to a low-molecular-weight oil component such as n-hexane and methanol.

Hereinafter, the present invention will be described in more detail with reference to Examples and Experimental Examples.

However, the following Examples and Experimental Examples are merely illustrative of the present invention, and the present invention is not limited to the following Examples and Experimental Examples.

Example  One

A melamine sponge having a width of 3 cm, a width of 3 cm and a thickness of 3 cm was prepared, and the prepared melamine sponge was washed with distilled water and ethanol three times to remove impurities remaining on the surface.

Separately, 25 wt% aqueous ammonia was added dropwise to 100 mL of a 1M aqueous solution of zinc acetate (Zn (OAc) ₂ ) to dissolve all the white zinc acetate precipitated in the aqueous zinc acetate solution. At this time, the pH of the solution was 10 to 11. The dissolved zinc acetate aqueous solution was added to the reaction flask and the melamine sponge prepared above was immersed so as to be immersed in an aqueous solution of zinc acetate. Then, a microwave oven (Model: KR-G20EW, ) Was irradiated with microwave (output: 1120 ± 20 W, frequency: 2450 ± 10 MHz). At this time, the microwave irradiation and the melamine sponge irradiated with microwaves were left to stand for aging. This process was repeated three times. In addition, each irradiation step irradiated with microwave was performed for 60 ± 2 seconds, and each aging step in which the microwave irradiated melamine sponge was left was performed for 30 ± 2 seconds. After the completion of the above processes, the temperature of the zinc acetate aqueous solution was cooled to room temperature (20 ± 1 ° C.) for 5 minutes, the melamine sponge immersed in the aqueous zinc acetate solution was taken out, washed with distilled water and air dried. The composite (MS-ZnO-SA) was prepared by dipping the dried melamine sponge in 100 ml of a 10 mM stearic acid solution dissolved in ethanol for 5 minutes and drying it naturally. The average thickness of the stearic acid layer on the surface was 3 to 8 Nm.

Comparative Example  One

A melamine sponge having a width of 3 cm, a width of 3 cm and a thickness of 3 cm was prepared, and the prepared melamine sponge was washed with distilled water and ethanol three times to remove impurities remaining on the surface.

Separately, 25 wt% aqueous ammonia was added dropwise to 100 mL of a 1M aqueous solution of zinc acetate (Zn (OAc) ₂ ) to dissolve all the white zinc acetate precipitated in the aqueous zinc acetate solution. At this time, the pH of the solution was 10 to 11. The dissolved zinc acetate aqueous solution was added to the reaction flask and the melamine sponge prepared above was immersed so as to be immersed in an aqueous solution of zinc acetate. Then, a microwave oven (Model: KR-G20EW, ) Was irradiated with microwave (output: 1120 ± 20 W, frequency: 2450 ± 10 MHz). At this time, the microwave irradiation and the melamine sponge irradiated with microwaves were left to stand for aging. This process was repeated three times. In addition, each irradiation step irradiated with microwave was performed for 60 ± 2 seconds, and each aging step in which the microwave irradiated melamine sponge was left was performed for 30 ± 2 seconds. After the completion of the above-mentioned treatments, the temperature of the aqueous zinc acetate solution was cooled to room temperature (20 占 1 占 폚) for 5 minutes. Thereafter, the melamine sponge immersed in the aqueous zinc acetate solution was taken out, washed with distilled water, and naturally dried to prepare a composite (MS-ZnO).

Comparative Example  2

A melamine sponge having a width of 3 cm, a width of 3 cm and a thickness of 3 cm was prepared, and the prepared melamine sponge was washed with distilled water and ethanol three times to remove impurities remaining on the surface. The complex (MS-SA) was prepared by immersing the melamine sponge in 100 ml of a 10 mM concentration of stearic acid solution dissolved in ethanol for 5 minutes and drying it naturally. The average thickness of the stearic acid layer on the surface was 3 to 8 nm.

Experimental Example  One

In order to confirm the physical properties of the surface of the composite according to the present invention, a scanning electron microscope (SEM) was performed on the composite (MS-ZnO-SA) prepared in Example 1 and a melamine sponge without treatment, The results are shown in Fig.

As shown in FIG. 1, the composite according to the present invention has a micro-nano-type surface structure.

Specifically, referring to FIG. 1, the composite of Example 1 was found to have a micro-nanostructure on its surface, with zinc oxide particles randomly radially aggregating on open pores of a thinner melamine sponge. In addition, the average size of the pores formed in the composite is about 100 탆 to 150 탆, the zinc oxide particles agglomerated in random radial form have a rod having an average thickness of about 0.8 to 1.2 탆 and an average length of about 3 to 5 탆, Type particles.

From these results, it can be seen that the composite according to the present invention has a micro-nano structure in which a zinc oxide particle layer is randomly radially aggregated on the surface of a sponge porous melamine sponge having three-dimensionally open pores so that the surface roughness of the composite is maximized, The surface properties such as specific surface area are excellent.

Experimental Example  2

In order to confirm the surface components of the composite according to the present invention, KBr pellets were prepared for each of the unmelted melamine sponge and the composite prepared in Example 1, and then Fourier transform infrared spectroscopy was performed in the infrared region of 1,000 to 4,000 cm ^-1 (FT-IR) analysis was performed.

X-ray photoelectron spectroscopy (XPS) was measured on the melamine sponge and each complex, and the measured results are shown in FIGS. 2 and 3. FIG.

As shown in FIGS. 2 and 3, it can be seen that the composite according to the present invention has a structure in which fatty acid is coated on the surface of the zinc oxide particle layer aggregated on the melamine sponge.

2 is a graph showing X-ray photoelectron spectroscopy (XPS) results of the untreated melamine sponge and the composite prepared in Example 1. In the case of a melamine sponge, an oxygen element (O), a nitrogen element (N) was confirmed that the peak representing 1s combination of elements (C), wherein the ratio of the peak intensity of the nitrogen element (N) and a carbon element _{(C) ((P C0 /} P N0) was found to be about 0.9 to 1.1.

In contrast, the composite of Example 1 has a peak indicating the 1s bond of the oxygen element (O), the nitrogen element (N) and the carbon element (C), and a peak indicating the 2p3 bond of the zinc element (Zn) (P _C1 / P _N1 ) of peak intensity between the nitrogen element (N) and the carbon element (C) was found to be about 1.4 to 1.6 due to stearic acid.

3 is a graph showing Fourier Transform-Infrared Spectroscopy (FT-IR) results of the untreated melamine sponge and the composite prepared in Example 1. Unlike the untreated melamine sponge, the composite of Example 1 had 2862 ± Peaks indicating symmetrical and asymmetric elongation vibrations of alkylene groups (-CH ₂ -) derived from stearic acid at 2 cm ^-1 and 2930 ± 2 cm ^-1 were confirmed.

From these results, the composite of the present invention means that the zinc oxide particle layer is placed on the melamine sponge, and the surface of the zinc oxide particle layer surrounds the fatty acid.

Experimental Example  3

In order to evaluate the water separation efficiency of the complex according to the present invention, the following experiment was conducted.

end) Contact angle  evaluation

The untreated melamine sponge and the complexes prepared in Example 1 and Comparative Examples 1 and 2 were subjected to static water contact angle measurement using a contact angle meter (Model: SmartDrop, manufactured by Femtofab Co. Ltd) Sliding water contact angle, shedding water contact angle and static oil contact angle were measured. At this time, each measurement was performed by dropping 10 μl of water or oil drop on the surface for each measurement, and repeatedly performed three times to derive the average value. The results are shown in Table 1 and FIG.

Water (H ₂ O) Static contact angle Slip angle Flow angle Untreated group Not measurable Not measurable Not measurable Example 1 159 ± 1 ° 10 ± 1 ° 9 ± 1 ° Comparative Example 1 90 ± 1 ° Not measurable Not measurable Comparative Example 2 90 ± 1 ° 50 ± 1 ° 50 ± 1 °

As shown in Table 1 and Fig. 4, it can be seen that the composite according to the present invention has pyrochrome, water repellency and lipophilic properties on the surface.

Specifically, the composite prepared in Example 1 exhibited a static water contact angle of 158 ° to 160 ° indicating affinity to water, and the water slip angle and water flow angle indicating water repellency were 11 ° or less, specifically, Lt; RTI ID = 0.0 > 11 < / RTI > In addition, the composite absorbed all of the oil and was unable to measure the static oil contact angle indicating lipophilicity.

On the other hand, untreated melamine sponge has high affinity for both water and oil, absorbing water or oil falling on the surface during contact angle measurement, so that water or static oil contact angle as well as slip angle and flow angle for water can not be measured (In fact ≒ 0 °). In addition, the composites prepared in Comparative Examples 1 and 2 each showed a hydrophobic property including a zinc oxide particle layer or a stearic acid layer on the surface, but the degree of contact was low and the static water contact angle was less than 120 °. In addition, the composites of Comparative Examples 1 and 2 were remarkably low in water repellency and showed a slip angle and a flow angle of 15 ° or more with respect to water.

From these results, it can be seen that the composite according to the present invention has a structure in which zinc oxide particles are aggregated randomly in a radial form on a melamine sponge and has a structure in which the surface of the zinc oxide particles surrounds the fatty acid, whereby not only the affinity to oil is remarkably high, The water repellency is excellent.

B) Evaluation of effluent separation efficiency by oil type

A unmelted melamine sponge, a composite (diameter 7 +/- 2 cm, height 1 cm) prepared in Example 1 or Comparative Examples 1 and 2 was fixed to a tube having a diameter of 7 cm equipped with a stainless steel mesh as a stopper, A beaker was prepared under the tube. Thereafter, a solution (30 ml) in which the oil and water were mixed in a volume ratio of 1: 1 was poured into the tube and waited until all the oil in the solution passed through the untreated melamine sponge or complex, The oil used was methanol, n-hexame, vacuum oil, gasoline, canola oil or diesel. When the oil in the solution is absorbed and passed through the untreated melamine sponge or complex, the volume of the water remaining on the upper part without passing through the melamine sponge or the composite is measured, and the separation efficiency of oil and water is deduced Respectively. The result is shown in Fig.

[Formula 1]

Oil water separation efficiency (k) = V ₁ / V ₀ X 100

In Equation 1,

V ₁ represents the volume of water remaining on the top of the melamine sponge or composite after separation,

V ₀ represents the volume of water contained in the pre-separation mixed solution.

As shown in Fig. 5, it can be seen that the composite according to the present invention has excellent water-oil separation efficiency regardless of the kind of oil.

Specifically, it was confirmed that the composite prepared in Example 1 was separated from water at a high efficiency of 95% or more with respect to oils such as hexane, vacuum oil, gasoline, canola oil, light oil and the like. In particular, it has been shown that the complex separates more than 98% of the water-soluble methanol from water.

On the contrary, the composite prepared in Comparative Example 1 or Comparative Example 2 showed little separation of water and oil, and the water separation efficiency of the oil was less than 10%.

From these results, it can be seen that the composite according to the present invention has excellent oil-water separation efficiency.

Experimental Example  4.

In order to evaluate the durability of the composite according to the present invention, the following experiment was conducted.

A) Stress evaluation for deformation of composite

The untreated melamine sponge and the composite (diameter 7 ± 2 cm, height 1 cm) prepared in Example 1 were prepared, and the prepared composite was fixed in a universal testing machine. The stress of the composite was measured by compressing it to a strain of 50% or 70% as described above. The static contact angle of the compressed composite was measured, and the measured results are shown in Table 2.

Untreated group The complex of Example 1 transform 50% 70% 50% 70% Stress (MPa) 0.000320 ± 0.00005 0.000399 ± 0.00005 0.000310 ± 0.00005 0.000365 ± 0.00005 Static water contact angle - - 159 ± 1 ° 159 ± 1 °

As shown in Table 2, the composite according to the present invention is excellent in durability because it has excellent resistance to external force.

Specifically, it was confirmed that the composite prepared in Example 1 had a stress of 0.0003 to 0.0004 which is equivalent to that of a melamine sponge having high elasticity (no treatment group) when a strain of 50% or 70% was applied. In addition, the composite of Example 1 maintained surface energy and surface roughness even after deformation, resulting in a high static water contact angle of 150 ° or more.

From these results, it can be seen that the composite according to the present invention has excellent durability, so that even when an external force is applied, the elastic force is not impaired and excellent super-hydrophobicity is realized.

B) Evaluation of effluent separation efficiency by reuse

Each of the composite (diameter 7 ± 2 cm, height 1 cm) prepared in Example 1 was fixed to a tube having a diameter of 7 cm equipped with a stainless steel mesh as a stopper, and a beaker was prepared under the tube. Then, a solution (30 ml) in which the oil and water were mixed in a volume ratio of 1: 1 was poured into the tube and the oil mixed with water was waited until all of the oil in the solution passed through the complex, ), Hexane (n-hexame), vacuum oil, gasoline, canola oil or diesel. When all of the oil in the solution passed through the composite, the volume of the water remaining on the upper portion of the composite was not passed through the composite, and the separation efficiency between oil and water was deduced. This process was repeated 50 times, and the obtained results are shown in FIG. 6 and Table 3.

unit: % Methanol Hexane Vacuum oil Gasoline Canola oil Diesel 1 time 99.89 99.75 97.99 98.56 99.99 97.52 5 times 99.55 99.80 95.20 96.30 94.32 96.22 10 times 99.01 98.32 90.36 90.00 92.54 90.33 15 times 98.32 97.01 85.47 89.21 90.33 84.19. 20 times 95.32 96.00 82.10 87.33 89.22 79.62 25 times 94.09 95.34 79.33 86.33 87.26 70.00 30 times 93.27 93.22 75.24 80.22 85.36 65.33 35 times 92.36 90.32 60.00 74.36 80.27 60.33 40 times 90.06 89.66 55.21 70.01 70.00 50.12 45 times 85.36 85.36 50.00 67.25 65.11 42.19 50 times 82.31 80.32 40.36 55.03 60.21 38.24

As shown in FIG. 6 and Table 3, it can be seen that the complex according to the present invention can be subjected to oil-water separation with high efficiency even by repeated use.

Specifically, it was confirmed that the composite prepared in Example 1 was subjected to oil-water separation of oil and water in a volume ratio of 1: 1 by repeating 30 times to exhibit a high separation efficiency of 60% or more regardless of the oil component . In addition, oil components such as n-hexane and methanol showed a high separation efficiency of 80% or more even when oil separation was performed 50 times or more.

From these results, it can be seen that the composite according to the present invention has a large average BET specific surface area due to the sequential formation of a zinc oxide particle layer and a fatty acid layer which are aggregated randomly in a radial pattern on a melamine resin matrix having a porous structure on the sea surface, , Excellent durability, lipophilic property, super hydrophobic property and super water repellency, and is excellent in oil-water separation efficiency, so that it can be usefully used as an adsorbent oil-water separating material used for large-scale oil-water separation such as oil removal from the ocean.

Claims (11)

A melamine resin matrix having a spongy porous structure;
A zinc oxide particle layer surrounding the matrix surface; And
And a fatty acid layer having 10 to 30 carbon atoms surrounding the zinc oxide particle layer,
Wherein the zinc oxide particle layer has a structure in which two or more zinc oxide particles are randomly radially aggregated based on any one point of the surface of the matrix.
The method according to claim 1,
The zinc oxide particles,
An average length of 1 탆 to 10 탆 and an average thickness of 0.1 탆 to 2 탆,
Wherein the ratio (L / D) of the average thickness (D) to the average length (L) is 3 to 6.
The method according to claim 1,
The complex,
The average static water contact angle is 150 DEG or more,
A composite having an average sliding contact angle of 15 ° or less.
The method according to claim 1,
The melamine resin matrix comprises open pores,
Wherein the average size of the pores is 50 탆 to 500 탆.
The method according to claim 1,
The fatty acid includes at least one selected from the group consisting of capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachic acid, and behenic acid.
Immersing a melamine resin matrix having a sponge-like porous structure in a zinc oxide precursor solution and irradiating microwave to form a zinc oxide particle layer on the surface of the matrix; And
Immersing a melamine resin matrix having a zinc oxide particle layer on its surface in a solution of 10 to 30 carbon atoms in which a fatty acid is dissolved to form a fatty acid layer surrounding the zinc oxide particle layer,
Wherein the zinc oxide particle layer has a structure in which two or more zinc oxide particles are agglomerated in a random radial pattern based on an arbitrary point on the surface of the matrix.
The method according to claim 6,
Wherein the zinc oxide precursor solution comprises 0.1M to 2M zinc ions (Zn ^< ^{2 + &} gt ^; ).
The method according to claim 6,
Wherein the output of the microwave is from 1,000 W to 1,500 W.
The method according to claim 6,
Wherein the frequency of the microwave is from 2,000 MHz to 3,000 MHz.
The method according to claim 6,
In the microwave irradiation,
An irradiating step of subjecting the melamine resin matrix to microwave treatment for 10 to 100 seconds; And
And an aging step of allowing the microwave irradiated melamine resin matrix to stand for 1 to 60 seconds,
Wherein the irradiation step and the aging step are repeated n times (n < = 10).
A material for water softening including the composite according to claim 1.

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