KR100855171B1 - Preparation method of nanocomposites in supercritical carbon dioxide - Google Patents

Abstract

A method for preparing a nanocomposite by using supercritical carbon dioxide is provided to obtain a nanocomposite comprising an inorganic oxide in a conductive polymer in an eco-friendly manner with a high conversion while facilitating easy separation of a desired product and avoiding a solubilization problem. A method for preparing a nanocomposite comprising an inorganic oxide homogeneously in a conductive polymer comprises the steps of performing surface modification of an inorganic oxide with a silane coupling agent, and polymerizing the surface-modified inorganic oxide together with a conductive monomer and oxidant catalyst in supercritical carbon dioxide, wherein the conductive monomer is monomer X represented by the following formula 1 or monomer Y represented by the following formula 2, includes a polymer obtained by homopolymerization of monomer X or monomer Y, and has a weight average molecular weight of 1,000-10,000,000; the inorganic oxide is selected from TiO2, SiO2, Al2O3, CaCO3, ZrO3, ZnO2 and SnO2; the oxidant catalyst is selected from ammonium persulfate, ferric chloride, cupric chloride, copper(II) fluoroborate, copper(II) oxychloride and potassium perchromate; and the supercritical carbon dioxide has a temperature of 31-100 deg.C and a pressure of 137.9-500 bars. In the formulae, Z is an imine or vinyl; Q is S, Se or N-R7; and each of R1-R7 is selected from H, OH, a halogen, halide, C50 or lower alkyl, alkoxy, alkylcarboxy, alkylester, alkylhydroxyl, nitroalkyl, cyanoalkyl, haloalkyl, oxyhaloalkyl, cyanohaloalkyl, aryl, oxyaryl, haloaryl, nitroaryl, cyanoaryl, oxyhaloalkylaryl, haloalkylaryl, nitrohaloalkylaryl and cyanohaloalkylaryl.

Description

Manufacturing method of nanocomposite using supercritical carbon dioxide {PREPARATION METHOD OF NANOCOMPOSITES IN SUPERCRITICAL CARBON DIOXIDE}

Figure 1 (a) is a TEM photograph of pure titanium dioxide.

Figure 1 (c) is a TEM photograph of the surface-modified titanium dioxide.

1 (b) and (d) are TEM photographs of polypyrrole / titanium dioxide nanocomposites at different magnifications.

Figure 2 (a) is the FT-IR spectrum of the polypyrrole polymer.

2 (b) is the FT-IR spectrum of the polypyrrole / titanium dioxide nanocomposite prepared according to Example 2. FIG.

3 is an EDX spectrum of the polypyrrole / titanium dioxide nanocomposite prepared according to Example 2. FIG.

4 (a) is a TGA spectrum of a polypyrrole polymer.

Figure 4 (b) is the TGA spectrum of the polypyrrole / titanium dioxide nanocomposite prepared according to Example 2.

5 (a) is an XRD spectrum of a polypyrrole / titanium dioxide nanocomposite prepared according to Example 2. FIG.

5 (b) is the XRD spectrum of pure titanium dioxide.

5 (c) is an XRD spectrum of a polypyrrole polymer.

The present invention relates to a method for producing a nanocomposite (nanocomposite) using supercritical carbon dioxide, and more particularly, to a surface-modified inorganic oxide and nanocomposite of the surface-modified inorganic oxide and the conductive polymer through polymerization in supercritical carbon dioxide It relates to a method of manufacturing.

Recently, researches on making nanocomposites by inserting inorganic particles into polymers have been actively conducted.

In US Patent No. 6599631, an inorganic particle / polymer composite including chemical bonds between components of a composite is synthesized and applied to an electric, optical and electro-optical device.

Among various kinds of conductive polymers, polypyrrole, polyaniline, polythiophene, etc. have been studied for practical reasons due to various advantages such as easy manufacturing method, high conductivity, and excellent stability.

With the development of nanotechnology, nanomaterials having different forms such as spherical nanoparticles, core-cell nanoparticles, nanocapsules, nanotubes, and nanocomposites composed of conductive polymers can be manufactured by various synthetic methods.

In particular, nanocomposites of conductive polymers and inorganic oxides have a unique microstructure, improved physical and electro-optic properties, and are used in a wide range of applications, including battery cathodes, microelectronics, and solar cells. Polyaniline and silica nanocomposite particles were prepared in Langmuir, 1992, Vol. 8, 2178-2182, and polypyrrole and silica nanocomposite particles in Journal of Material Chemistry, 1994, Vol. 4, 935-942. In Chemistry of Materials, 1995, Vol. 7, pp. 171-178, various studies have been made, including the production of polypyrrole and tin dioxide nanocomposites.

In addition, the Republic of Korea Patent Publication 2006-0091134, functionalized with aniline on the surface of the silica nanoparticles, and the conductive polymer is grafted to the functionalized silica nanoparticles well soluble in an organic solvent through an oxidative polymerization reaction, the conductive polymer capped silica Nanoparticles were synthesized.

However, in such a manufacturing method, solubilization problem occurs in the process of removing the solvent, especially when using an organic solvent may cause problems of high cost and environmental pollution.

Accordingly, the present invention is to solve the above problems, an object of the present invention is to use supercritical carbon dioxide, environmentally friendly, simple separation of the product, there is no solubilization problem, the inorganic oxide to the conductive polymer with high conversion rate It is to provide a method for producing a nanocomposite containing uniformly.

In order to achieve the above technical problem, the present invention, a surface-modified inorganic oxide using a silane coupling agent, and the surface-modified inorganic oxide is polymerized in a supercritical carbon dioxide with a conductive monomer, an oxidant catalyst to produce a nanocomposite It provides a method for producing a nanocomposite containing an inorganic oxide in a conductive polymer comprising the step of.
Supercritical carbon dioxide is an inexpensive, nonflammable, non-toxic solvent, and is used as an environmentally friendly solvent in the fields of extraction and the like. In particular, it has the advantage of increasing the conversion rate in the chemical reaction by having a high density and the same viscosity as the gas and excellent diffusion properties and fast material transfer.

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

In the present invention, the nanocomposite refers to a composite including nanoparticles having an average particle diameter of several hundred nanometers or less. The emergence of uniform nanoparticles has been a major influence in the technical field. These nanoscale materials show new physical properties compared to conventional particles. Nanoparticles have a very large surface area to volume ratio and a large surface defect ratio than conventional bulk materials, so the surface properties of the material are very important.

The nanocomposite of the present invention includes one or more inorganic oxides in one conductive polymer particle, and surface-modified inorganic oxides and conductive monomers are obtained by using a catalyst in supercritical carbon dioxide.

The inorganic oxide of the present invention is titanium dioxide (TiO ₂ ), silicon dioxide (SiO ₂ ), dialuminum trioxide (Al ₂ O ₃ ), calcium tricarbonate (CaCO ₃ ), zirconium trioxide (ZrO ₃ ), zinc dioxide (ZnO ₂₎ ), Tin dioxide (SnO ₂ ) may be one or more selected from. However, the inorganic oxide of the present invention is not limited only to the above examples.

The inorganic oxide may be used to purchase the one prepared in the nano-size, or may be used by synthesizing the inorganic oxide of various sizes.

Surface modification in the step of surface modification of the inorganic oxide of the present invention can be easily prepared by known methods described in the Journal of Materials Chemistry, 1997, Vol. 7, 1527-1532, which is a known method.

In the method for producing a nanocomposite in which inorganic oxide is uniformly dispersed in a conductive polymer using the supercritical carbon dioxide of the present invention, the surface-modified inorganic oxide and the conductive monomer are polymerized together with a catalyst for 1 to 2 hours in supercritical carbon dioxide. It is manufactured by.

The conductive monomer of the present invention is a monomer X represented by the following formula (1) or a monomer Y represented by the formula (2), the conductive polymer can be prepared by using a monomer X or a monomer Y by a single or co-polymerization reaction thereof;

[Formula 1]

또는

또는

이고,

or

or

ego,

[Formula 2]

또는

이며,

or

Is,

Wherein Z is an imine group or a vinyl group, Q is S, Se or NR 7, and R 1, R 2, R 3, R 4, R 5, R 6 and R 7 are, independently from each other, hydrogen, a hydroxyl group, a halogen atom, a halide Alkyl groups, alkoxy groups, alkyl carboxyl groups, ylalkyl ester groups, alkylhydroxy groups, nitroalkyl groups, cyanoalkyl groups, haloalkyl groups, oxyhaloalkyl groups, nitroalkyl groups, cyanohaloalkyl groups, aryl groups, It is selected from the group consisting of an oxyaryl group, haloaryl group, nitroaryl group, cyanoaryl group, oxyhaloalkylaryl group, haloalkylaryl group, nitrohaloalkylaryl group, and cyanohaloalkylaryl group, Average molecular weight of the prepared polymer is 1,000 to 10,000,000.

The conductive polymer may be prepared by the following three methods:

1) a method of synthesizing a homopolymer of X by homopolymerizing the X monomer of Formula 1; 2) a method of synthesizing the homopolymer of Y by homopolymerizing the Y monomer of Formula 2; And 3) copolymerizing the monomer X of Formula 1 and the monomer Y of Formula 2 at a molar ratio of 0.01: 99.99 to 99.99: 0.01 to synthesize a copolymer polymer of X and Y.

The copolymer of monomers X and Y prepared by the method of 3) may be represented by the following formula (3);

 [Formula 3]

In the above formula,

또는

또는

이고,

or

or

ego,

또는

이며,

or

Is,

Z is an imine group or a vinyl group, Q is S, Se or NR 7, and R 1, R 2, R 3, R 4, R 5, R 6 and R 7 are, independently from each other, hydrogen, a hydroxyl group, a halogen atom, a halide, 50 carbon atoms. Within an alkyl group, an alkoxy group, an alkyl carboxyl group, an alkyl group, an alkylhydroxy group, a nitroalkyl group, a cyanoalkyl group, a haloalkyl group, an oxyhaloalkyl group, a nitroalkyl group, a cyanohaloylalkyl group, an aryl group, an oxyaryl group , Haloaryl group, nitroaryl group, cyanoaryl group, oxyhaloalkylaryl group, haloalkylaryl group, nitrohaloalkylaryl group, and cyanohaloalkylaryl group, m is the mole fraction For example, 0 ≦ m ≦ 1.0, n is a polymer degree of polymerization, 5 ≦ n ≦ 500,000, and the weight average molecular weight of the prepared polymer is 1,000 to 10,000,000.

Catalysts are required for these polymerization reactions, and a general oxidizing agent may be used as the catalyst of the polymerization reaction, and the oxidizing agent may be ammonium persulfate, ferric chloride, cupric chloride, copper fluoride (II), or copper oxide (II) chloride. And it is preferable to select and use from the group which consists of potassium dichromate.

In the supercritical carbon dioxide in which the reaction proceeds, the supercritical state is made at a temperature of 31 to 100 ° C. and a pressure of 137.9 to 500 bar. Preferably, the temperature is 40 ° C. and the pressure is 137.9 bar.

The content of the inorganic oxide in the conductive polymer of the nanocomposite is preferably 5 to 50% by weight.

The polymerization in the supercritical carbon dioxide is preferably 1 to 2 hours, in which a yield of generally 95% by weight or more can be obtained.

Hereinafter, preferred embodiments of the present invention are described. However, the following examples are only preferred examples of the present invention and are not limited by the following examples of the present invention.

< Example  1>

Supercritical Carbon Dioxide  Within Nanocomposite  Manufacturing method

The process for preparing nanocomposites in supercritical carbon dioxide is based on 0.4 g of surface modified titanium dioxide (TiO) of uniform nano-sized titanium dioxide (TiO) by the known method described in Journal of Materials Chemistry, 1997, Vol. 7, 1527-1532. ₂ ) the silane compound was treated on the surface of the particles] and 1 g of pyrrole was dispersed in a suspension state, and then charged in a stainless high pressure reactor. Iron trichloride was dissolved in a small amount of methanol, placed in a high pressure reactor, and a Teflon-coated magnetic bar was simultaneously placed in a high pressure reactor to perform polymerization. The pressure inside the reactor was controlled using an ISCO syringe pump (Model 260D), and the reaction temperature and pressure were fixed at 40 ℃ and 137.9 bar, respectively. All polymerization proceeded for 2 hours and the reaction was terminated by cooling the reactor to room temperature. The obtained polymer particles were easily separated from the reaction mixture by reducing the carbon dioxide into a gaseous state, and the polymerization product was used to remove residual iron chloride. Finally it was dried in an oven at 50 ° C. for 24 hours. Yield measured after drying showed more than 90% by weight, it was confirmed that the pyrrole polymer is a nanocomposite containing inorganic oxide particles using TGA, XRD and IR. As a result of TEM measurement, it was confirmed that the titanium dioxide nanoparticles were uniformly distributed in the conductive polymer.

The present invention is composed of a nanocomposite of a conductive polymer and an inorganic oxide, at the same time having the physical advantages of the inorganic material and processability and elasticity of the polymer, and polymerization using supercritical carbon dioxide, the separation of the product is very simple. In addition, the conversion rate is high, and there is no problem of solubilization in the removal of the solvent, and the manufactured nanocomposite includes battery cathode, constructing nanoscopic assemblies in sensors, microelectronics, It is effective to make practical use in various fields such as solar cells.

Claims (9)

In the method for producing a nanocomposite comprising an inorganic oxide uniformly in the conductive polymer, the inorganic oxide is surface-modified using a silane coupling agent, and the surface-modified inorganic oxide in a supercritical carbon dioxide with a conductive monomer, an oxidant catalyst In the step of polymerization, The conductive monomer is a monomer X represented by the following formula (1) or a monomer Y represented by the formula (2), wherein the conductive polymer is obtained by a single polymerization reaction of the monomer X or monomer Y, the weight average molecular weight is 1,000 to 10,000,000 Electrically conductive polymers: [Formula 1]

or

or

ego, [Formula 2]

or

Is, Wherein Z is an imine group or a vinyl group, Q is S, Se or NR 7, and R 1, R 2, R 3, R 4, R 5, R 6 and R 7 are, independently from each other, hydrogen, a hydroxyl group, a halogen atom, a halide Alkyl groups, alkoxy groups, alkyl carboxyl groups, ylalkyl ester groups, alkylhydroxy groups, nitroalkyl groups, cyanoalkyl groups, haloalkyl groups, oxyhaloalkyl groups, nitroalkyl groups, cyanohaloalkyl groups, aryl groups, It includes one selected from the group consisting of an oxyaryl group, haloaryl group, nitroaryl group, cyanoaryl group, oxyhaloalkylaryl group, haloalkylaryl group, nitrohaloalkylaryl group, and cyanohaloalkylaryl group. and, The inorganic oxide is titanium dioxide (TiO ₂ ), silicon dioxide (SiO ₂ ), dialuminum trioxide (Al ₂ O ₃ ), calcium tricarbonate (CaCO ₃ ), zirconium trioxide (ZrO ₃ ), zinc dioxide (ZnO ₂ ) tin dioxide (SnO ₂ ) and selected from The oxidant catalyst is selected from ammonium persulfate, ferric chloride, cupric chloride, copper fluoride (II), copper chloride (II) chloride and potassium dichromate, The supercritical state of the supercritical carbon dioxide is a method of producing a nanocomposite, characterized in that the temperature of the carbon dioxide is 31 ~ 100 ℃, the pressure is 137.9 ~ 500 bar. The method of claim 1, wherein the nanocomposite comprises one or more inorganic oxides in one conductive polymer particle. delete delete delete The method of claim 1, wherein the content of the inorganic oxide surface-modified inside the conductive polymer of the nanocomposite is 5 to 50% by weight. delete The conductive polymer according to claim 1, which is obtained by copolymerizing a monomer X represented by Formula 1 and a monomer Y represented by Formula 2, wherein the weight average molecular weight is 1,000 to 10,000,000. [Formula 3]

In the above formula,

or

or

ego,

or

Is, Z is an imine group or a vinyl group, Q is S, Se or NR 7, and R 1, R 2, R 3, R 4, R 5, R 6 and R 7 are, independently from each other, hydrogen, a hydroxyl group, a halogen atom, a halide, 50 carbon atoms. Within alkyl group, alkoxy group, alkyl carboxyl group, alkyl group, alkylhydroxy group, nitroalkyl group, cyanoalkyl group, haloalkyl group, oxyhaloalkyl group, nitroalkyl group, cyanohaloylalkyl group, aryl group, oxyaryl group , Haloaryl group, nitroaryl group, cyanoaryl group, oxyhaloalkylaryl group, haloalkylaryl group, nitrohaloalkylaryl group, and cyanohaloalkylaryl group, m is the mole fraction The method of manufacturing a nanocomposite, wherein 0 ≦ m ≦ 1.0 and n is a polymer degree of polymerization, wherein 5 ≦ n ≦ 500,000. The method of manufacturing a nanocomposite according to claim 8, wherein the conductive polymer having a weight average molecular weight of 1000 to 10,000 obtained by copolymerizing the monomer X and the monomer Y is copolymerized at a molar ratio of 0.01: 99.99 to 99.99: 0.01. .

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