KR101516675B1 - Silica based nano sheet, dispersion sol of silica based nano sheet and method for preparing thereof - Google Patents

Abstract

The present invention relates to a silica based nanosheet, dispersion sol of silica based nanosheet and a manufacturing method thereof. The silica based nanosheet is not condensed and has the average particle size of 0.1 to 10.0 μm and the thickness of 0.5 to 30 nm, and dispersion sol of silica based nanosheet can be manufactured by peeling off the layer of silicates and preparing a nanosheet thereof and distributing the resulting material to organic solvent that yields silica sol. The silica based nanosheet and the dispersion sol of silica based nanosheet has excellent mechanical, thermal, and chemical properties. The silica based nanosheet and the dispersion sol of silica based nanosheet combine with other organic materials as hybrids to form inorganic-organic compound, allowing to be applied to various fields.

Description

Technical Field [0001] The present invention relates to a silica-based nano-sheet, a silica-based nano-sheet, a silica-based nano-sheet,

The present invention relates to a silica-based nanosheet, a silica-based nanosheater dispersion sol and a method for producing the same, and more particularly to a silica-based nanosheet dispersion sol having a two-dimensional plate shape and being excellent in mechanical, thermal and chemical properties as crystalline particles, Based nano-sheet dispersed sol, and a method for producing the same.

Silica has excellent physical properties such as corrosion resistance, chemical resistance, abrasion resistance, heat resistance and hardness, and is actively utilized in such fields as structural materials, protective coating materials and abrasive materials. The application range of silica having such excellent properties Is expanding to electric and electronic materials and information materials.

In particular, it is possible to use such silica as a nanosheet for a variety of applications, but there is no currently available example and it is difficult to apply it as a base material in various fields because it forms a composite by combining with an organic material.

In addition, the production of nanosheets using metal compounds other than silica has a problem in that it is not economical in terms of yield and processing cost in the production process.

There has been developed a porous metal compound nano-sheet having mesopores of nano unit, but it has a problem that the production yield is low and the characteristics such as particle size and porosity are difficult to control, and as a result, it is used as a material for various applications Limited.

Therefore, there is a demand for development of a method for manufacturing nanosheets and nanosheets which are excellent in physical and chemical properties and easy to manufacture and applicable to various application fields.

Korean Patent Publication No. 10-2011-0045190 Korean Patent Publication No. 10-2012-0023149

Therefore, an object of the present invention is to solve such conventional problems, and it is an object of the present invention to provide a silica-based nanosheet having excellent dimensional, mechanical, thermal and chemical properties as a two- , A silica-based nanosheet dispersion sol, and a process for producing the same.

It is another object of the present invention to provide a silica-based nanosheet dispersion sol which is easy to produce a hybrid material with an organic material and a method for producing the same.

In order to achieve the above object, the silica-based nanosheets according to an embodiment of the present invention may be in the form of non-agglomerated particles having an average particle diameter of 0.1 to 10.0 탆 and a thickness of 0.5 to 30 nm.

The silica-based nanosheets may be formed by delaminating a layered silicate.

The layered silicate may be selected from the group consisting of kaemite, bentonite, montmorillonite, mica, kaolin, zeolite, vermiculite, illite, laponite, ), And combinations thereof.

The silica-based nanosheater dispersion sol according to one embodiment of the present invention is a silica-based nanosheet having an average particle diameter of 0.1 to 10.0 탆 and a thickness of 0.5 to 30 nm; And organic solvents.

The silica-based nanosheets may be formed by delaminating a layered silicate.

The silica-based nanosheet may be surface-treated with a surface treatment agent containing at least one of a silane compound and an organic surfactant.

The organic solvent may be selected from the group consisting of N-methyl-2-pyrrolidone, dimethylacetamide, dimethylformamide, dimethylsulfoxide, alcohol, hexane, and combinations thereof.

A method for producing a silica-based nanosheet dispersion sol according to an embodiment of the present invention includes: an ion exchange step of acid-treating a layered silicate containing interstitial metal ions to ion exchange the metal ion with a proton (H ⁺ ); ; A step of removing the layered silicate by reacting the quaternary ammonium hydroxide compound with the ion-exchanged layered silicate to produce a nanosheet; A surface treatment step of surface-treating the nanosheet with a surface treatment agent comprising at least one of a silane compound and an organic surfactant; And a dispersing step of dispersing the nanosheet in an organic solvent to produce a dispersion sol.

In the ion exchange step, the layer silicate containing the interstitial metal ion may be formed by mixing silica sol and metal hydroxide.

In the layered silicate comprising intercalated metal ions, the layered silicate is selected from the group consisting of kanemite, bentonite, montmorillonite, mica, kaolin, zeolite, vermiculite, , Illite, laponite, and combinations thereof.

The metal ion may be at least one of an alkali metal ion or an alkaline earth metal ion.

The acid may be a strong acid.

The quaternary ammonium hydroxide compound may be in a concentration of 0.5 to 5 moles.

Wherein the quaternary ammonium hydroxide compound is selected from the group consisting of methyltributylammonium hydroxide, diethyldimethylammonium hydroxide, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, tetraoctylammonium hydroxide, trimethylethylammonium hydroxide, (2-hydroxyethyl) trimethylammonium hydroxide, benzyltriethylammonium hydroxide, hydroxy (2-hydroxyethyl) trimethylammonium hydroxide, Hydroxypropyl) trimethylammonium, and combinations thereof.

In the surface treatment step, the surface treatment agent may be 1 to 7 parts by weight based on 100 parts by weight of the nanosheet.

The silane compound may be a compound represented by the following formula (1).

[Chemical Formula 1]

_{R (CH 2) x Si (} R ') 4-y

Wherein R is an epoxy, a hydrocarbon, a hydrocarbonamine, a hydrocarbon halide, an isocyanate or a benzene, x is an integer of 1 to 16, R 'is alkoxy, acetoxy or hydroxy, Lt; / RTI >

The silane compound may be selected from the group consisting of 3-aminopropyltriethoxysilane, 3-aminopropyldimethylmethoxysilane, 3-aminopropylmethyldimethoxysilane, 3- (aminopropyl) ethyldimethoxysilane, , 3-aminopropylphenyldimethoxysilane, 2-aminoethyltriethoxysilane, 4-aminobutyltriethoxysilane, 4-aminobutyltrimethoxysilane, 4-aminobutylmethyldimethoxysilane, 3- 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, and combinations thereof. .

The surface treatment step may further include addition of acetic acid.

The organic solvent may be selected from the group consisting of N-methyl-2-pyrrolidone, dimethylacetamide, dimethylformamide, dimethylsulfoxide, alcohol, hexane, and combinations thereof.

The nanosheet may have an average particle diameter of 0.1 to 10.0 mu m and a thickness of 0.5 to 30 nm.

The silica-based nanosheet according to the present invention is two-dimensional plate-like and has crystallinity, so that it is superior in mechanical, thermal and chemical properties to amorphous silica particles which are spherical and spherical in shape of the conventional zero-dimensional.

In addition, the silica-based nanosheets dispersed sol according to the present invention is a dispersion of silica-based nanosheets in a solvent and is excellent in dispersibility, so that it can hybridize with other organic materials to facilitate formation of organic-inorganic composites, have. Particularly, a coating agent and a coating film can be prepared and used easily as a hard coating film or an insulating material.

The method for producing a silica-based nanosheet dispersion sol according to the present invention can provide a method for producing a silica-based nanosheet dispersion sol by directly removing the layered silicate.

In addition, physical and chemical properties can be controlled by uniformly synthesizing the size by reducing the size distribution by optimizing the materials and steps used to manufacture the silica-based nanosheets dispersion sol.

The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the description of the claims.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram sequentially showing a method for producing a silica-based nanosheet dispersion sol according to an embodiment of the present invention. FIG.
FIG. 2 is an image obtained by analyzing the shape of particles of a carneitic plate used in the preparation of the silica-based nanosheets of Examples 1, 2 and 3 using a scanning electron microscope (SEM).
FIG. 3 is a graph showing the results of the measurement of the silica-based nanosheets in the process of producing the silica-based nanosheets according to Example 4, (b) ion exchange, (c) X-ray diffraction diagram after measurement.
FIG. 4 is an image obtained by drying the silica-based nanosheet dispersion sol prepared in Example 4 and analyzing it by a field emission scanning electron microscope (FE-SEM).
5 is an image obtained by analyzing the silica-based nanosheet prepared in Example 3 by transmission electron gusarud (transmission electron microscope, TEM).
6 is an image obtained by analyzing the silica-based nanosheet prepared in Example 6 with a transmission electron microscope (TEM).
7 is an image obtained by analyzing the silica-based nanosheets prepared in Example 4 with an atomic force microscope (AFM).

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving them will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. To fully disclose the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims.

Unless defined otherwise, all terms (including technical and scientific terms) used herein may be used in a sense commonly understood by one of ordinary skill in the art to which this invention belongs. Also, commonly used predefined terms are not ideally or excessively interpreted unless explicitly defined otherwise.

Hereinafter, the silica-based nanosheets, the silica-based nanosheets dispersed sols and the method for producing the same will be described in detail.

The silica-based nanosheets according to one embodiment of the present invention may have a non-aggregated form and a plate-like form.

The conventional silica-based nanosheets exist in the form of agglomerates in the aggregated state, but in the present invention, the nanosheets of the silica-based nanosheets have a form in which the nanosheet particles are separated and not agglomerated. Such a non-agglomerated silica-based nanosheet can be applied to formation of a very thin film using each nanosheet.

The silica-based nanosheets may have an average particle diameter of 0.1 to 10.0 탆 and a thickness of 0.5 to 30 nm, preferably an average particle diameter of 0.5 to 5.0 탆, and a thickness of 0.5 to 20 nm.

Here, the particle size is measured by a field emission scanning electron microscope (FE-SEM) or a transmission electron microscope (TEM) as a method of expressing the particle size and thickness quantified by a measurement method, and an atomic force microscope (AFM) Which means that the size and thickness of the particles are measured at the same time. The average particle diameter can be expressed numerically by a measurement method to represent the average size of the population. However, it is generally used. The mode diameter indicates the maximum value of the distribution, the median diameter corresponds to the median value of the integral distribution curve, The average particle size is a number average particle size, unless otherwise specified in the present invention. D50 (distribution ratio of 50 (measured by a dynamic light scattering type particle size distribution analyzer) % Of the particle size).

The silica-based nanosheets may be prepared from a layered silicate, and the layered silicate may be formed by peeling.

The basic structure of the layered silicate is composed of a combination of a silica layer of a tetrahydral structure and an alumina layer of an octahydral structure and can be produced through a condensation reaction of -OH functional groups between two layers. Layered silicate structure octa hydroxide LAL Mg ^{2 +} in place of Al ^{3 +} ions in the layer, Fe ^{+ 2,} Fe ^{+ 3} ions in this, and in the LAL-tetrahydroxy layer is Al ³⁺ ion in place of Si ^{+ 4} ion can be substituted isotropic .

The layered silicate has a very large surface area and has a structure in which a very thin sheet is stacked on the order of tens to hundreds of sheets.

Specifically, the layered silicate may be selected from the group consisting of kaemite, bentonite, montmorillonite, mica, kaolin, zeolite, vermiculite, illite or lapo Laponite, and may be used in combination of two or more of them in some cases.

The silica-based nanosheet dispersion sol according to an embodiment of the present invention includes a silica-based nanosheet and an organic solvent. Specifically, the silica-based nanosheet may be dispersed in an organic solvent.

The silica-based nanosheet may be surface-treated with a surface treatment agent containing at least one of a silane compound and an organic surfactant. The dispersion degree of the silica-based nanosheets can be improved through the surface treatment.

The organic solvent may serve as a dispersion medium for dispersing the silica-based nanosheets.

The organic solvent may be N-methyl-2-pyrrolidone, dimethylacetamide, dimethylformamide or dimethylsulfoxide, alcohol, hexane or the like, or a mixture of two or more of them may be used. Can be dispersed to a degree of excellent dispersion.

As shown in FIG. 1, the silica-based nanosheet dispersion sol according to an embodiment of the present invention includes an ion exchange step (S10), a peeling step (S20), a surface treatment step (S30) and a dispersion step (S40) . ≪ / RTI >

The ion exchange step S10 is a step of ion-exchanging the metal ion with a proton (H ⁺ ) by acid treatment of a layered silicate containing interstitial metal ions.

The layered silicate containing the interstratified metal ions may be formed by mixing silica sol and metal hydroxide.

The metal hydroxide may be an alkali metal hydroxide or an alkaline earth metal hydroxide, preferably sodium hydroxide, potassium hydroxide or calcium hydroxide.

Specifically, the layered silicate containing intercalated metal ions may be prepared by mixing a silica sol with a metal hydroxide to form a mixed solution, drying the mixed solution at a temperature of 100 to 150 ° C. for 100 to 300 minutes, Firing, and then washing with water.

If the drying time of the mixture is less than 100 minutes, moisture of the mixed solution does not escape and gelation is difficult, so that formation of a layered silicate may be difficult, and if it exceeds 300 minutes, the mixture may harden and hardly form particles.

In this case, the weight ratio of the silica sol and the metal oxide may be 1: 0.8 to 1: 1.2, preferably 1: 0.9 to 1: 0.9. If the content ratio is exceeded, it may be difficult to form a layered silicate containing interstitial metal ions.

The metal ion may be an alkali metal ion or alkaline earth metal, preferably may be a Na ^+, K ⁺ or Ca ^{2 +.}

The acid may be a strong acid, and the layered silicate containing the interstitial metal ion may be supported on the acid to be ion-exchanged.

The strong acid may be preferably sulfuric acid, hydrochloric acid or nitric acid, more preferably hydrochloric acid.

The time for carrying the interlayer silicate to the acid may be from 15 to 30 hours, preferably from 20 to 28 hours. If the supporting time is less than 15 hours, only a part of the interlayer silicate proceeds ion exchange, and if the supporting time exceeds 30 hours, the improvement effect of ion exchange is insignificant, which is uneconomical.

The concentration of the acid is preferably 0.5 to 2M, more preferably 0.8 to 1.2M. When the concentration of the acid is less than 0.5M, the ion exchange is difficult. When the concentration exceeds 2M, the layered silicate is dissolved in the acid, so that the ion exchange of the particles is difficult.

After the layered silicate is treated with an acid to ion-exchange the metal ion with the proton, the acid solution containing the layered silicate is dehydrated, washed with tertiary purified water, dried at a temperature of about 80 to 100 DEG C for 4 to 8 hours To obtain a dry ion-exchanged layered silicate.

The peeling step (S20) is a step of peeling the ion-exchanged layered silicate in the ion exchange step (S10), and is a step of peeling each of the nanosheets constituting the layered silicate.

Specifically, the ion-exchanged layered silicate may be supported on the quaternary ammonium hydroxide compound solution to be peeled off with each of the nanosheets.

Wherein the quaternary ammonium hydroxide compound is selected from the group consisting of methyltributylammonium hydroxide, diethyldimethylammonium hydroxide, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, tetraoctylammonium hydroxide, trimethylethylammonium hydroxide, Trimethylammonium hydroxide, (2-hydroxyethyl) triethylammonium hydroxide, (2-hydroxyethyl) tripropylammonium hydroxide or (1- Hydroxypropyl) trimethylammonium. Of these, tetrapropylammonium hydroxide can be preferably used. In some cases, two or more of them may be mixed and used.

The quaternary ammonium hydroxide compound may be used in a concentration of 0.5 to 5 moles, preferably 1 to 3 moles. When the concentration of the quaternary ammonium hydroxide compound is less than 0.5 molar, the layered silicate is difficult to peel off. When the concentration of the quaternary ammonium hydroxide compound exceeds 5 molar, the layered silicate dissolves and can not be peeled off with the nanosheet.

It is preferable that the quaternary ammonium hydroxide solution containing nanosheets separated by the peeling step (S20) is lyophilized to obtain a powdered silica-based nanosheet.

The surface treatment step S30 is a step of treating the surface of the nanosheet obtained through the peeling step S20 so as to improve the degree of dispersion when the nanosheet is mixed with another organic material to form a composite.

Specifically, the nanosheets may be dispersed in an organic solvent, preferably an alcohol-based solvent, and then the surface treatment agent may be added to the shaker, followed by mixing for 15 to 60 minutes.

The surface treating agent for modifying the surface of the nanosheet may be a silane compound or an organic surfactant, or a mixture of two or more thereof.

The silane compound may be a compound represented by the following formula (1).

[Chemical Formula 1]

_{R (CH 2) x Si (} R ') 4-y

Wherein R is an epoxy, a hydrocarbon, a hydrocarbonamine, a hydrocarbon halide, an isocyanate or a benzene, x is an integer of 1 to 16, R 'is alkoxy, acetoxy or hydroxy, Lt; / RTI >

The silane compound may preferably be an aminoalkoxysilane compound, and specifically includes 3-aminopropyltriethoxysilane, 3-aminopropyldimethylmethoxysilane, 3-aminopropylmethyldimethoxysilane, 3- (aminopropyl) ethyl Aminopropyltrimethoxysilane, 4-aminobutyltrimethoxysilane, 4-aminobutyltrimethoxysilane, 4-aminopropyltrimethoxysilane, 4-aminopropyltrimethoxysilane, - aminobutylmethyldimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane or 3-glycidoxypropyltrimethoxysilane And more preferably 3-aminopropyltriethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-mercaptopropyltriethoxysilane or 3-glycidoxypropyltrimethoxysilane, use Can.

As the organic surfactant, a cationic surfactant may be used. Specifically, a cationic surfactant such as triton X-100 and polyvinyl alcohol (PVA) may be used.

The surface treating agent may be used in an amount of 1 to 7 parts by weight, preferably 2 to 6 parts by weight, based on 100 parts by weight of the nanosheet. When the content of the surface treatment agent is less than 1 part by weight, the surface of the nanosheet is difficult to be modified, and when it exceeds 7 parts by weight, the dispersion degree of the dispersed sol may be lowered.

In the surface treatment step (S30), it is preferable to further add acetic acid in addition to the silane compound, which can control the hydrolysis and condensation of the silane compound. The acetic acid may be added in an amount of 0.1 to 20 parts by weight, preferably 1 to 8 parts by weight, based on 100 parts by weight of the silane compound.

The dispersing step S40 is a step of dispersing the nanosheet surface-modified by the surface treatment step S30 in an organic solvent to prepare a dispersion sol.

The organic solvent may be N-methyl-2-pyrrolidone, dimethylacetamide, dimethylformamide or dimethylsulfoxide, or a mixture of two or more thereof.

Specifically, in the dispersing step S40, the organic solvent added in the surface treatment step S30 is removed under an evaporator, and the nanosheet is dispersed in the organic solvent added in the dispersing step S40, A sheet dispersed sol can be produced.

[Example]

Hereinafter, the results of experiments conducted to demonstrate the excellent effects of the hollow plate material of the present invention are shown.

Hereinafter, the present invention will be described in detail by way of examples, but the present invention is not limited thereto.

Example  One

50 wt% water-based TM-50 silica sol (LUDOX) and sodium hydroxide were mixed at a molar ratio of 1: 0.8, dried in an oven at 100 ° C. for 3 days, and then calcined at 700 ° C. for 24 hours to obtain Na ⁺ ≪ / RTI > The carnemite was supported on 1 M hydrochloric acid for 24 hours to carry out ion exchange, and then sufficiently washed to prepare a cation-exchange type layered silicate. Subsequently, the cation-exchange type caneite is delaminated at a concentration of 1 mol of tetrafluoroammonium hydroxide to 1 mol of the H ⁺ ion concentration of the H ⁺ ion-exchanged layered silicate to produce a nanosheet, followed by lyophilization. After the freeze-dried nanosheets were dispersed in ethanol, 3-aminopropyltriethoxysilane (5 parts by weight of 3-aminopropyltriethoxysilane per 100 parts by weight of nanosheets) and a small amount of acetic acid were added thereto, For 30 minutes. After the surface-treated nanosheets were added to N-methyl-2-pyrrolidone, the ethanol was separated in an evaporator to prepare a silane-modified silica-based nanosheet dispersion sol dispersed in N-methyl-2-pyrrolidone .

Example  2

A silica-based nanosheets dispersion sol was prepared under the same conditions as in Example 1, except that tetramethylammonium hydroxide was used in a concentration of 2 molar in Example 1.

Example  3

A silica-based nanosheet dispersion sol was prepared under the same conditions as in Example 1 except that tetramethylammonium hydroxide was used in a concentration of 3 molar in Example 1.

Example  4

After drying for 3 days in an oven at 100 ° C using sodium silicate, the layered silicate was formed by baking at 700 ° C for 24 hours. The layered silicate was immersed in 1M hydrochloric acid for 24 hours to carry out ion exchange and then sufficiently washed to prepare a cation exchange type cannate. Subsequently, the cation-exchange type caneite is delaminated at a concentration of 1 mol of tetrafluoroammonium hydroxide to 1 mol of the H ⁺ ion concentration of the H ⁺ ion-exchanged layered silicate to produce a nanosheet, followed by lyophilization. After freeze-dried nanosheets were dispersed in ethanol, 3-aminopropyltriethoxysilane (5 parts by weight of 3-aminopropyltriethoxysilane was added to 100 parts by weight of nanosheets) and a small amount of acetic acid were added thereto, For 30 minutes. After the surface-treated nanosheets were added to N-methyl-2-pyrrolidone, the ethanol was separated in an evaporator to prepare a silane-modified silica-based nanosheet dispersion sol dispersed in N-methyl-2-pyrrolidone .

Example  5

A silica-based nanosheets dispersion sol was prepared under the same conditions as in Example 1, except that tetramethylammonium hydroxide was used in a concentration of 2 molar in Example 4.

Example  6

A silica-based nanosheets dispersion sol was prepared under the same conditions as in Example 1, except that tetramethylammonium hydroxide was used in a concentration of 3 molar in Example 4.

The particle size and thickness, and the yield of nanosheet, of the silica-based nanosheets dispersed sol prepared by the methods of Examples 1 to 6 were measured and are shown in Table 1. The thickness of the nanosheets was measured with an atomic force microscope (AFM). The nanosheets were coated on the surface of the Si wafer, and the probe was hung on the end of the cantilever. And the atomic phase of the surface was measured.

Particle size (탆) Thickness (nm) Nanosheet yield (%) Example One 0.3-10 0.5-30 63.5 2 0.5-10 68.7 3 0.5-5 71.8 4 0.1-4 0.5-30 64 5 0.5-10 76 6 0.5-5 77

The silica particles are spherical and amorphous in a zero-dimensional shape, but the silica-based nanosheets of the present invention are in a crystalline phase, so that it is expected that they can be easily applied to the insulating properties.

Fig. 2 is a graph showing the results of analyzing the shape of particles of a carnemate plate used in the production of the silica-based nanosheets of Examples 1, 2 and 3 by a scanning electron microscope. .

FIG. 3 is a graph showing the results of the measurement of the silica-based nanosheets in the process of producing the silica-based nanosheets according to Example 4, (b) ion exchange, (c) As a result of X-ray diffraction after measurement, it has a carnemate structure before ion exchange. After the ion exchange, the interlayer spacing of the layered silicate becomes four Na cations in the unit cell (bc plane) It is confirmed that the interlayer spacing is reduced due to the exchange of 4 H cations and the desorption of water molecules as adsorbed water. It is confirmed that the layered silicate is well separated from the nanosheet due to the disappearance of the diffraction pattern due to separation of the nanosheet through (c) . In particular, when the transparent nanosheet sol is dried and measured on the powder, it can be seen that the XRD pattern inherent to the layered silicate appears and is well separated by the crystalline nano-sheet.

FIG. 4 is a graph showing the results of analysis of a silica-based nanosheet dispersed sol prepared in Example 4 by a field emission scanning electron microscope (FE-SEM) can see.

5 shows the results of analysis of the silica-based nanosheets prepared in Example 3 by TEM. As a result, nanosheets having a grain size of about 0.3 to 10 mu m and a thickness of about 0.5 nm, .

FIG. 6 shows the results of analysis of the silica-based nanosheets prepared in Example 6 by TEM. As a result, nanosheets of about 3 to 5 layers having a particle size of 0.3 to 2 μm and a thickness of about 1.5 to 3 nm were observed.

7 shows the result of analysis of the silica-based nanosheets prepared in Example 4 by AFM. As a result, a nanosheet having a particle size of 0.5 to 3 mu m and a thickness of about 4 nm was observed.

The scope of the present invention is not limited to the above-described embodiments, but may be embodied in various forms of embodiments within the scope of the appended claims. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the appended claims.

Claims (20)

As a silica-based nanosheet,
The silica-based nanosheets are in a non-aggregated form,
An average particle diameter of 0.1 to 10.0 mu m, a thickness of 0.5 to 30 nm,
Wherein the layered silicate is formed by being peeled off.
delete The method according to claim 1,
The layered silicate may be selected from the group consisting of kaemite, bentonite, montmorillonite, mica, kaolin, zeolite, vermiculite, illite, laponite, ), And a combination thereof.
A silica-based nanosheet having an average particle diameter of 0.1 to 10.0 占 퐉, a thickness of 0.5 to 30 nm, and a layered silicate peeled; And
A silica-based nanosheet dispersion sol containing an organic solvent.
delete 5. The method of claim 4,
Wherein the silica-based nanosheets are surface-treated with a surface treatment agent containing at least one of a silane compound and an organic surfactant.
5. The method of claim 4,
Wherein the organic solvent is selected from the group consisting of N-methyl-2-pyrrolidone, dimethylacetamide, dimethylformamide, dimethylsulfoxide, alcohol, hexane and combinations thereof.
An ion exchange step of acid-treating a layered silicate containing interstitial metal ions to ion exchange the metal ions with a proton (H ⁺ );
A step of removing the layered silicate by reacting the quaternary ammonium hydroxide compound with the ion-exchanged layered silicate to produce a nanosheet;
A surface treatment step of surface-treating the nanosheet with a surface treatment agent comprising at least one of a silane compound and an organic surfactant; And
And dispersing the nanosheet in an organic solvent to produce a dispersion sol.
9. The method of claim 8,
In the ion exchange step, the layered silicate containing the interstitial metal ion is formed by mixing silica sol and metal hydroxide.
9. The method of claim 8,
In the layered silicate comprising intercalated metal ions, the layered silicate is selected from the group consisting of kanemite, bentonite, montmorillonite, mica, kaolin, zeolite, vermiculite, Wherein the sol is selected from the group consisting of silica, lignite, laponite, and combinations thereof.
9. The method of claim 8,
Wherein the metal ion is at least one of an alkali metal ion and an alkaline earth metal ion.
9. The method of claim 8,
Wherein the acid is a strong acid.
9. The method of claim 8,
Wherein the quaternary ammonium hydroxide compound is in a concentration of 0.5 to 5 moles.
14. The method according to claim 8 or 13,
Wherein the quaternary ammonium hydroxide compound is selected from the group consisting of methyltributylammonium hydroxide, diethyldimethylammonium hydroxide, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, tetraoctylammonium hydroxide, trimethylethylammonium hydroxide, (2-hydroxyethyl) trimethylammonium hydroxide, benzyltriethylammonium hydroxide, hydroxy (2-hydroxyethyl) trimethylammonium hydroxide, Hydroxypropyl) trimethylammonium, and combinations thereof. The present invention relates to a process for producing a silica-based nanosheet dispersion sol.
9. The method of claim 8,
Wherein the surface treatment agent is 1 to 7 parts by weight based on 100 parts by weight of the nanosheet in the surface treatment step.
16. The method according to claim 8 or 15,
Wherein the silane compound is a compound represented by the following formula (1).
[Chemical Formula 1]
_{R (CH 2) x Si (} R ') 4-y
Wherein R is an epoxy, a hydrocarbon, a hydrocarbonamine, a hydrocarbon halide, an isocyanate or a benzene, x is an integer of 1 to 16, R 'is alkoxy, acetoxy or hydroxy, Lt; / RTI >
17. The method of claim 16,
The silane compound may be selected from the group consisting of 3-aminopropyltriethoxysilane, 3-aminopropyldimethylmethoxysilane, 3-aminopropylmethyldimethoxysilane, 3- (aminopropyl) ethyldimethoxysilane, , 3-aminopropylphenyldimethoxysilane, 2-aminoethyltriethoxysilane, 4-aminobutyltriethoxysilane, 4-aminobutyltrimethoxysilane, 4-aminobutylmethyldimethoxysilane, 3- 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, and combinations thereof. (Preparation method of nanosheet dispersion sol).
9. The method of claim 8,
Wherein the surface treatment step further comprises adding acetic acid.
9. The method of claim 8,
Wherein the organic solvent is selected from the group consisting of N-methyl-2-pyrrolidone, dimethylacetamide, dimethylformamide, dimethylsulfoxide, alcohol, hexane and combinations thereof.
9. The method of claim 8,
Wherein the nanosheet has an average particle diameter of 0.1 to 10.0 m and a thickness of 0.5 to 30 nm.

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