KR101173989B1 - Method of manufacturing for a polymer membrane containing nano sized metal particles - Google Patents

Abstract

The present invention relates to a method for manufacturing a separator containing metal nanoparticles, (i) dissolving a metal salt in a low concentration polymer solution and then reducing the metal salt to reduce the metal salt in nano size metal particles (metal nanoparticles) in a low concentration polymer solution. (Ii) adding the low concentration polymer solution in which the metal nanoparticles are formed to the high concentration polymer solution to uniformly disperse the metal nanoparticles in the high concentration polymer solution, and (iii) the metal nanoparticles It characterized in that it comprises a step of producing a separator from the polymer solution of high concentration dispersed evenly.

The present invention can easily control the size of the metal nanoparticles by forming the metal nanoparticles in the polymer solution, it is possible to maximize the dispersion effect of the metal nanoparticles.

As a result, the separator prepared according to the present invention has excellent stain resistance and a long service life.

Metal particles, nano particles, membranes, metal salts, reduction, pollution resistance, service life.

Description

Method for manufacturing a membrane containing metal nanoparticles {Method of manufacturing for a polymer membrane containing nano sized metal particles}

The present invention relates to a method for producing a separator containing metal particles having a size of 10 ~ 1,000nm (hereinafter referred to as "metal nanoparticles"), more specifically the present invention is a polymer solution for producing a membrane membrane The present invention relates to a method for producing a separator containing metal nanoparticles which further improves dispersibility of metal nanoparticles and fouling resistance of the separator.

Organic and inorganic nanoparticles can be applied to various fields due to their unique mechanical, optical, magnetic and catalytic properties. In particular, the control of the composition and size of various nanoparticles in the electronic or optical field is an important factor in determining the quality and price of products, and research and development on these are being actively conducted. Nanoparticles as a reaction catalyst have a much larger surface area than other catalysts, and even a small amount of use can be used for further effects and the activity is also known to be excellent.

Among various metal nanoparticles, silver and gold nanoparticles having excellent bactericidal and bactericidal properties have been widely used in real life.

Nanoparticles exhibiting such excellent activity can generally be obtained by reducing the compound through ultraviolet or plasma irradiation. Korean Patent No. 10-0379250 proposes a method of forming a single-phase solution by adding a silver salt or a gold salt to a polymer solution, forming a polymer film with the solution, and then irradiating ultraviolet rays to form nanoparticles in the film. This is because electronic excitation of the functional group in the polymer is generated by ultraviolet irradiation, and the metal salt is thereby reduced.

As such, the polymer membrane including the nanoparticles is a polymer membrane in which the characteristics of the nanoparticles are expressed, and its application fields are various, and in particular, it may be a method of improving the characteristics of the separator in the water treatment field.

Korean Patent No. 10-0444126 reports that a titanium compound having a photocatalytic property can be dispersed in a separator having a nanoparticle size in a separator to suppress a fouling effect that degrades the membrane during water treatment. . The deterioration of the permeation characteristics of the membrane in the water treatment process is because the biofilm is formed on the membrane surface by the microorganisms for a long time operation. Therefore, the method can maintain the performance of the membrane for a long time by inhibiting the reaction of microorganisms on the surface of the membrane using a titanium compound, but since the used catalyst is a photocatalyst, it is disadvantageous that long-term contamination resistance can be maintained only when UV or sunlight is present. have.

The present invention is to prepare a membrane having excellent fouling resistance by forming the metal nanoparticles in the polymer solution for preparing the membrane to easily control the size and to maximize the dispersion effect by inhibiting the aggregation of the nanoparticles.

In order to achieve the above object, a method of preparing a separator containing the metal nanoparticles of the present invention includes (i) dissolving a metal salt in a low concentration polymer solution and then reducing the metal salt to reduce the size of the nanoparticle metal particles in the low concentration polymer solution ( Metal nanoparticles), (ii) adding the low concentration polymer solution in which the metal nanoparticles are formed to a high concentration polymer solution to evenly disperse the metal nanoparticles in the high concentration polymer solution, and (iii) It characterized in that it comprises a step of producing a separator from the polymer solution of the high concentration in which metal nanoparticles are evenly dispersed.

Hereinafter, the present invention will be described in detail.

The present invention comprises three steps of forming metal nanoparticles in a low concentration polymer solution, adding and dispersing the formed metal nanoparticles to a high concentration polymer solution, and forming a high concentration polymer solution including nanoparticles as a separator. do.

The present invention first dissolves a metal salt in a low concentration polymer solution and then reduces the metal salt to form metal nanoparticles in the low concentration polymer solution.

The metal salt may be selected from Sc, Ti, Zr, Cr, Mo, W, Mn, Tc, Re, Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, and Zn. Preference is given to using metal compounds containing species or two or more elements.

As a reactant for reducing the metal salt to metal nanoparticle particles, depending on the type of metal salt, a reducing agent such as Na ₂ CO ₃ , Na ₂ S ₂ O _4, etc. is mainly used, and a surfactant may be used simultaneously with the reducing agent. It may be.

The concentration of the metal salt in the low concentration polymer solution is preferably 0.001 to 1 mol%, more preferably 0.01 to 0.5 mol%.

When the concentration is less than 0.001 mol%, the effect of improving the stain resistance is hardly observed. When the concentration is more than 1 mol%, dispersibility may be reduced due to agglomeration of metal nanoparticles.

On the other hand, as the polymer constituting the low concentration polymer solution, it is preferable to use a polymer that is the same as the polymer constituting the high concentration polymer solution described later or that can be dissolved in a high concentration polymer solution.

Next, the low concentration polymer solution in which the metal nanoparticles are formed as described above is added to the high concentration polymer solution to uniformly disperse the metal nanoparticles in the high concentration polymer solution.

The high concentration of the polymer solution is composed of the polymer or polymer and additives constituting it. In other words, the additive is optionally used.

The polymer constituting the high concentration of the polymer solution is one resin or two or more resins selected from polyacetate, polyacrylonitrile, polysulfone, polyethersulfone, polyvinylidenephthalate, polyamide, polyimine and derivatives thereof Mixtures and the like can be used.

The content of the polymer in the high concentration polymer solution is 5 to 50% by weight, more preferably 10 to 30% by weight.

On the other hand, as an additive constituting a high concentration of the polymer solution, one or a mixture of glycol compounds, hydrophilic polymers, glycerin, water, and an organic solvent may be used.

Polyethylene glycol, polypropylene glycol, etc. may be used as a glycol compound, and polyvinylpyrrolidone etc. may be used for a hydrophilic polymer.

The content of the additive in the high concentration polymer solution is preferably 5 to 20% by weight.

As a solvent of the low concentration polymer solution and the high concentration polymer solution, methyl formamide, N-methyl-2-pyrrolidone, dimethylacetamide, etc. may be used, and it is preferable to use the same solvent, but depending on the characteristics Different solvents that can be dissolved may also be used together.

Next, a separation membrane is manufactured by a method similar to a phase separation method of a polymer solution having a high concentration in which metal nanoparticles are uniformly dispersed by the above processes.

The shape of the separator may be any of hollow fiber, tubular, disk and flat membrane.

Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples. However, the present invention is not limited by the following examples.

Example  One

After dissolving silver salt (AgBF ₄ ) in dimethylacetamide in which 1% by weight of polysulfone was dissolved, Na ₂ CO ₃ was added as a reducing agent and stirred while heating to 70 ° C. at room temperature to form a solution containing silver nanoparticles (inclusive). Prepared. Formation of silver nanoparticles in the solution was confirmed by UV-Vis spectrometer.

Meanwhile, 17% by weight of polysulfone resin, 11% by weight of polyvinylpyrrolidone, and 4% by weight of polyethylene glycol were added to 68% by weight of dimethylacetamide, followed by stirring and dissolving to prepare a transparent polymer solution.

The polymer solution containing silver nanoparticles was prepared by adding and dispersing the solution containing silver nanoparticles prepared above at a time interval to the transparent polymer solution.

Next, using a phase separation method to prepare a separator in the form of a flat membrane with a polymer solution containing silver nanoparticles, and then bundling them to prepare a module.

The results of evaluating various properties of the prepared membrane and module are shown in Table 1.

Example  2

Separators and modules were prepared in the same manner as in Example 1, except that AgSO ₃ CF ₃ was used instead of AgBF ₄ as the silver salt.

The results of evaluating various properties of the prepared membrane and module are shown in Table 1.

Example  3

After dissolving silver salt (AgBF ₄ ) in dimethylacetamide in which 1% by weight of polysulfone was dissolved, Na ₂ CO ₃ was added as a reducing agent and stirred while heating to 70 ° C. at room temperature to form a solution containing silver nanoparticles (inclusive). Prepared. Formation of silver nanoparticles in the solution was confirmed by UV-Vis spectrometer.

Meanwhile, 20% by weight of polyether sulfone resin, 7% by weight of polyvinylpyrrolidone, and 5% by weight of polypropylene glycol were added to 68% by weight of dimethylacetamide, followed by stirring and dissolving to prepare a transparent polymer solution.

The polymer solution containing silver nanoparticles was prepared by adding and dispersing the solution containing silver nanoparticles prepared above at a time interval to the transparent polymer solution.

Next, using a phase separation method to prepare a separator in the form of a flat membrane with a polymer solution containing silver nanoparticles, and then bundling them to prepare a module.

The results of evaluating various properties of the prepared membrane and module are shown in Table 1.

Example  4

After dispersing gold salt (HAuCl ₄ ) in N-methyl-2-pyrrolidone, Na ₂ S ₂ O ₃ was added as a reducing agent and stirred while heating to 70 ° C. at room temperature to prepare a solution of gold nanoparticle formation (inclusive). It was. Formation of gold nanoparticles in the solution was confirmed by UV-Vis spectrometer.

Meanwhile, 17% by weight of polysulfone resin, 11% by weight of polyvinylpyrrolidone, and 4% by weight of polyethylene glycol were added to 68% by weight of dimethylacetamide, followed by stirring and dissolving to prepare a transparent polymer solution.

The polymer solution containing gold nanoparticles was prepared by adding and dispersing the solution containing the gold nanoparticles prepared above at a time interval to the transparent polymer solution.

Next, using a phase separation method to prepare a membrane in the form of a flat membrane with a polymer solution containing gold nanoparticles, and then bundle them to prepare a module.

The results of evaluating various properties of the prepared membrane and module are shown in Table 1.

Comparative Example  One

17% by weight of polysulfone resin, 11% by weight of polyvinylpyrrolidone and 4% by weight of polyethylene glycol were added to 68% by weight of dimethylacetamide, followed by stirring and dissolving to prepare a transparent polymer solution.

Next, using a phase separation method to prepare a membrane in the form of a membrane with the polymer solution, and then bundling them to prepare a module.

The results of evaluating various properties of the prepared membrane and module are shown in Table 1.

Property evaluation result division Separator
General bacteria
Concentration (CFU / mL) Instantaneous flow rate (L / min) by accumulated flow rate of module 1,000ℓ
(Cumulative flow rate) 5,000ℓ
(Cumulative flow rate) 10,000ℓ
(Cumulative flow rate) Example 1 30 2.66 2.53 2.42 Example 2 45 2.56 2.36 2.31 Example 3 44 2.55 2.34 2.21 Example 4 22 2.68 2.64 2.53 Comparative Example 1 12,600 1.95 0.54 0.43

In the above table, Examples 1 to 4 containing the metal nanoparticles decreased the general bacterial concentration of the separator, but Comparative Example 1 containing no metal nanoparticles increased the general bacterial concentration of the separator.

In addition, in Examples 1 to 4, the instantaneous flow rate is kept constant even when the cumulative flow rate is increased, but in Comparative Example 1, it can be seen that the instantaneous flow rate decreases rapidly as the cumulative flow rate is increased.

In the present invention, the fouling resistance of the membrane and the water permeation performance of the membrane module were evaluated by the following method.

ㆍ Pollution resistance of the membrane (general bacterial concentration)

Raw water (1,500 CFU / mL) was charged to the module, the bacteria were incubated in a 37 ° C. incubator for 24 hours, and the general bacterial concentration in the packed water was measured in the module.

ㆍ membrane module Water transmission performance (Momentary flow rate by accumulated flow rate of module)

The instantaneous flow rates at 1,000 L, 5,000 L and 10,000 L at the pressure of 1 kg / cm 2 in each module were compared.

In the present invention, since the metal nanoparticles are formed in a polymer solution for preparing a separator, the size of the metal nanoparticles can be easily adjusted, and they can be uniformly dispersed in the separator.

The membrane prepared by the method of the present invention is excellent in fouling resistance and can be used as a water treatment membrane for home or medical treatment, and when used as an industrial water treatment membrane, fouling phenomenon can be minimized, thereby extending the service life.

Claims (12)

(Iii) dissolving a metal salt in a low concentration polymer solution and then reducing the metal salt using a reducing agent to form nano-sized metal particles (metal nanoparticles) in a low concentration polymer solution, (ii) forming metal nanoparticles. Adding a low concentration polymer solution to a high concentration polymer solution to uniformly disperse the metal nanoparticles in a high concentration polymer solution, and (i) preparing a membrane from the high concentration polymer solution in which the metal nanoparticles are evenly dispersed. A method for producing a separator containing metal nanoparticles, comprising the step. The metal salt of claim 1, wherein the metal salt is Sc, Ti, Zr, Cr, Mo, W, Mn, Tc, Re, Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au and Zn Method of producing a separator containing metal nanoparticles, characterized in that the metal compound containing one or two or more selected elements. delete The method according to claim 1, wherein the metal salt is reduced to the metal nanoparticles by using a surfactant together with a reducing agent. The method according to claim 1, wherein the concentration of the metal salt in the low concentration polymer solution is 0.001 to 1 mol%. The method of claim 1, wherein the polymer constituting the low concentration polymer solution is the same polymer as the polymer constituting the high concentration polymer solution, or a polymer that can be dissolved in a high concentration polymer solution. The method of claim 1, wherein the polymer solution of high concentration is composed of a polymer and an additive. The polymer constituting the high concentration polymer solution according to claim 1 or 7 is selected from polyacetate, polyacrylonitrile, polysulfone, polyethersulfone, polyvinylidenephthalate, polyamide, polyimine and derivatives thereof. Or a mixture of two or more kinds thereof. 8. The metal nanoparticle according to claim 7, wherein the additive constituting the high concentration polymer solution is one or a mixture of glycol compounds, polypropylene glycol, polyvinylpyrrolidone, glycerin, and water. Method of Preparation of Membrane. The method of claim 7, wherein the content of the polymer in the high concentration polymer solution is 5 to 50% by weight. The method of claim 7, wherein the content of the additive in the high concentration polymer solution is 5 to 20% by weight. The method of claim 1, wherein the separation membrane is one selected from the group consisting of hollow fiber, tubular, disk and flat membrane.