KR20160080533A - Porous membrane having Multi-function, Manufacturing method thereof and Reverse osmosis pretreatment filter - Google Patents

Abstract

The present invention relates to a multifunctional porous separation membrane and a method of manufacturing the same, and more particularly, to a multifunctional porous separation membrane that is capable of removing foreign matters such as organic pollutants and the like without using a glass fiber having harmful carcinogens, To a multi-functional porous separator having excellent removal performance, suppression of biofouling, and a long service life, as well as an excellent water permeation amount, and a method for producing the same.

Description

TECHNICAL FIELD [0001] The present invention relates to a multi-functional porous separator, a manufacturing method thereof, and an RO pretreatment filter (manufacturing method thereof and reverse osmosis pretreatment filter)

The present invention relates to a multifunctional porous separation membrane, a multifunctional porous separation membrane which is excellent in the removal performance of a microorganism and organic matter in water and virus removal performance, a method for producing the same, and an RO pre-treatment filter using the same.

Generally, there are numerous ionic substances and chemicals, including natural organic matter (NOM), in water, and they are not removed in the process of water treatment but act as a cause of generating new pollutants. In addition, the presence of pathogenic microorganisms, which have not been removed by chlorine disinfection, has recently been controversial. Pathogenic microorganisms, such as viruses, crytosphoridium, and Giardia, are released into the environment through human and animal feces and are present in not only sewage but also surface and groundwater. The virus has a size of 0.02-0.09 ㎛, a bacterium has a length of 0.4-14 ㎛, a width of 0.2-1.2 ㎛, and a protozoan such as cryptosporidium and zyhodia is relatively larger than viruses and bacteria. Because viruses are very small in size, they are hardly treated by general filtration. They form stable cysts and survive for several months in water. At present, in order to remove trace contaminants in water, advanced coagulation treatment, activated carbon adsorption and membrane filtration are proposed in the water treatment process. Recently, a large-scale study on the water treatment process using membranes is underway.

Particularly, membrane filtration has been recently studied and commercialized in advanced water treatment process. However, it is still not widely used due to economical cost and technical problems. Existing filters including membranes classified as reverse osmosis membrane (RO), nanofiltration membrane (NF), ultrafiltration membrane (UF), and microfiltration membrane (MF), use conventional pore size to measure contaminants in water It is a system to remove.

The main mechanism for removing contaminants from the membrane is to remove bacteria, viruses and organic contaminants floating in the water by applying a sieve effect, ie removal by particle size. In addition to the removal by the particle size, electrostatic adsorption according to the surface charge of the separation membrane filters the microorganisms and organic contaminants in the water, and this method has been studied in view of high permeability and high particle removal performance compared to a low operating pressure.

The microfibre filter widely used for conventional water treatment has a disadvantage in that the efficiency is low because the filtration area is small and there is no electrostatic force. The membrane filter has a disadvantage in that the filtration efficiency is high but the pressure loss is large. Therefore, studies have been made to increase the filtration efficiency of the fiber filter and decrease the pressure loss by applying an electrostatic force to the microfine fiber filter having the micro pores to overcome the disadvantages of the microfiber filter and the membrane filter.

For example, conventionally, a glass fiber is used as a basic filter material for removing organic contaminants and / or an antiviral filter material, and a positive charge-generating inorganic compound is added at the time of glass fiber production to prepare a positive charge filter (Korean Patent Laid-Open No. 10-2004-0301723, U.S. Patent No. 7,601,262, etc.). However, since this technique uses glass fibers, there is a concern that the water treatment process may be suitably complicated due to the hazardousness of carcinogens and the like, and there is a problem in that the compound to be added during production using glass fiber can not be diversified in the product group.

SUMMARY OF THE INVENTION It is an object of the present invention to effectively remove nano-sized organic contaminants and / or viruses, thereby reducing filtration efficiency and process operation cost of a reverse osmosis process. Friendly porous multi-functional separator.

In order to solve the above-mentioned problems, the present invention is characterized in that the multifunctional porous separation membrane comprises a meltblown-calendering nonwoven fabric calendered with a meltblown nonwoven fabric having a positive charge coating layer formed on the inside and the surface of the nonwoven fabric.

In one preferred embodiment of the present invention, the positive charge coating layer may include a cross-linking agent and a polyfunctional amine compound.

In one preferred embodiment of the present invention, the crosslinking agent is selected from the group consisting of a bisphenol A epoxy resin, a bisphenol F epoxy resin, a hydrogenated bisphenol A epoxy resin, a hydrogenated bisphenol F epoxy resin, a flame retarded epoxy resin, and a Novolac ) Type epoxy resins.

In one preferred embodiment of the present invention, the polyfunctional amine compound may include at least one selected from polyethyleneimine, diethylenetriamine, piperazine, dimethylenepiperazine, and diphenylamine.

In one preferred embodiment of the present invention, the positive charge coating layer has an average thickness of 0.01 to 1 μm.

As a preferred embodiment of the present invention, the meltblown nonwoven fabric may be a modified meltblown nonwoven fabric pretreated with a modifier.

In one preferred embodiment of the present invention, the modifier comprises 0.1 to 5 wt% of a polymer resin containing at least one selected from polyacrylic acid having a weight average molecular weight of 1,800 to 200,000 and polyvinyl alcohol having a weight average molecular weight of 1,800 to 200,000; And 95 to 99.9% by weight of a solvent containing at least one of C1 to C3 of an alcohol, acetone and water.

In one preferred embodiment of the present invention, the meltblown nonwoven fabric may include at least one selected from the group consisting of polypropylene fibers, polyethylene terephthalate fibers, polyethylene fibers, polyester fibers, nylon fibers and cellulose fibers .

In one preferred embodiment of the present invention, the meltblown nonwoven fabric may have a fineness of 0.5 to 10 탆 and an average pore diameter of 1 to 20 탆. The calendered meltblown calendering nonwoven fabric Can have an average pore diameter of 0.5 탆 to 15 탆.

In one preferred embodiment of the present invention, the meltblown nonwoven fabric has an average thickness of 0.1 mm to 2 mm, and the calendered meltblown calendering nonwoven fabric has an average thickness of 0.05 mm to 1.5 mm have.

In one preferred embodiment of the present invention, the meltblown nonwoven fabric has a basis weight of 80 to 400 g / m 2, and the calendered meltblown-calendering nonwoven fabric has a basis weight of 75 to 350 g / can do.

In another preferred embodiment of the present invention, the multifunctional porous separation membrane of the present invention has a surface charge of 10 mV to 40 mV.

In another preferred embodiment of the present invention, the multifunctional porous separation membrane of the present invention has an average water permeation rate of 25 ml / cm ² · min · bar to 150 ml / cm ² · min · bar and a cumulative purified water volume of 2,000 L to 3,800 L . ≪ / RTI >

In another preferred embodiment of the present invention, the multifunctional porous separation membrane of the present invention has a virus removal performance of 2.5 log or more and a humic acid removal performance of 80% to 99.9%.

In another preferred embodiment of the present invention, the multifunctional porous separation membrane of the present invention may be formed as one layer or two to three layers of the above-described porous separation membrane.

As another preferred embodiment of the present invention, the multifunctional porous separation membrane of the present invention may further comprise a spun-bonded nonwoven fabric as a support.

Another object of the present invention is to provide a method for manufacturing the above-described multifunctional porous separation membrane, comprising the steps of positively coating a meltblown nonwoven fabric with a positive charge coating agent; Forming a positive charge coating layer on the meltblown nonwoven fabric by heat crosslinking the nonwoven fabric subjected to positive charge coating; And calendering a meltblown nonwoven fabric having a positive charge coating layer formed thereon, thereby producing a multi-functional porous separation membrane.

According to a preferred embodiment of the present invention, the coating step may be performed by immersing the meltblown nonwoven fabric in the positive charge coating agent at 10 ° C to 35 ° C for 10 seconds to 30 minutes.

In one preferred embodiment of the present invention, the thermal crosslinking treatment is performed at 50 ° C to 130 ° C for 1 minute to 3 hours.

As a preferred embodiment of the present invention, the calendering of the calendering step may be performed at a pressure of 1 kgf / cm 2 to 5 kgf / cm 2 using rollers at 35 ° C to 130 ° C in a meltblown nonwoven fabric having a positive charge- And rolling at a speed of 1 mpm to 4 mpm to perform the calendering.

In one preferred embodiment of the present invention, the positive charge coating agent may include 0.1 to 5 parts by weight of a crosslinking agent and 0.3 to 8 parts by weight of a polyfunctional amine compound per 100 parts by weight of the solvent.

In a preferred embodiment of the present invention, the solvent is at least one selected from the group consisting of diethylene glycol, dimethylacetamide, dimethylformamide, N-methyl-2-pyrrolidone, ethanol, isopropyl alcohol, acetone, And the like.

In one preferred embodiment of the present invention, the crosslinking agent is selected from the group consisting of a bisphenol A epoxy resin, a bisphenol F epoxy resin, a hydrogenated bisphenol A epoxy resin, a hydrogenated bisphenol F epoxy resin, a flame retardant epoxy resin, And a resin.

In one preferred embodiment of the present invention, the polyfunctional amine compound may include at least one selected from the group consisting of polyethyleneimine, diethylenetriamine, piperazine, dimethylenepiperazine, and diphenylamine.

In one preferred embodiment of the present invention, the meltblown nonwoven fabric is a modified meltblown nonwoven fabric, and the modified meltblown nonwoven fabric is prepared by pretreating the surface and the interior of the nonwoven fabric with a modifier, To produce a meltblown nonwoven fabric; And drying the modified melt blown nonwoven fabric.

In a preferred embodiment of the present invention, the modified melt blown nonwoven fabric may be prepared by immersing the melt blown nonwoven fabric in a modifier at 10 ° C to 35 ° C for 10 seconds to 30 minutes .

In one preferred embodiment of the present invention, the modifier comprises 0.1 to 5 wt% of a polymer resin containing at least one selected from polyacrylic acid having a weight average molecular weight of 1,800 to 200,000 and polyvinyl alcohol having a weight average molecular weight of 1,800 to 200,000; And 95 to 99.9% by weight of a solvent containing at least one of C1 to C3 of an alcohol, acetone and water.

Another object of the present invention is a reverse osmosis (RO) pretreatment filter comprising the above-described various types of multifunctional porous separators.

The multifunctional porous separation membrane of the present invention has a high surface charge and is excellent in adsorption and removal ability against viruses and organic compounds having nano-sized anions. In addition, the multifunctional porous separation membrane of the present invention comprises an RO pretreatment filter, As a filter, it is possible to effectively remove the organic compounds that cause fouling, thereby increasing the use period of the post-treatment filter used in the water treatment system.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a SEM photograph of fibers in the nonwoven fabric before the meltblown nonwoven fabric is modified and coated. FIG.
Fig. 2 is a SEM photograph of the fibers in the coated meltblown nonwoven fabric prepared in Example 1. Fig.

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

As described above, conventionally, there are controversial hazards of carcinogens and the like due to the use of glass fibers, and there is a concern that they are suitable for use in a water treatment process and problems in which a product group due to a compound added during production using glass fibers can not be diversified .

Accordingly, the present invention has developed a multi-functional porous separator using an environmentally friendly nonwoven fabric instead of glass fiber as follows.

The multifunctional porous separation membrane of the present invention is a meltblown-calendering nonwoven fabric (hereinafter referred to as MB-calendaring nonwoven fabric) in which a meltblown nonwoven fabric (hereinafter referred to as MB nonwoven fabric) ), Comprising the steps of positively coating an MB nonwoven fabric with a positive charge coating agent; Forming a positive charge coating layer on the MB nonwoven fabric through heat crosslinking treatment of the MB nonwoven fabric subjected to positive charge coating; And calendering an MB nonwoven fabric having a positive charge coating layer formed thereon, thereby producing a multifunctional porous separation membrane.

In the present invention, the fibers constituting the MB nonwoven fabric in the step of performing the positive charge coating may be at least one selected from polypropylene fiber, polyethylene terephthalate fiber, polyethylene fiber, polyester fiber, nylon fiber and cellulose fiber, May include one or two or more selected from a polypropylene fiber, a polyethylene terephthalate fiber, a polyethylene fiber and a polyester fiber, more preferably one or two selected from a polypropylene fiber and a polyethylene terephthalate fiber have.

The fibers constituting the MB nonwoven fabric may have a fineness of 0.5 탆 to 10 탆 and an average pore size of 1 to 20 탆, preferably a fineness of 0.5 탆 to 8 탆 and an average pore size of 2 탆 to 15 탆, The fineness may preferably be 0.5 mu m to 7 mu m and the average pore size may be 2 mu m to 13 mu m. If the fineness of the fibers constituting the MB nonwoven fabric is less than 0.5 mu m, there may be a problem that the flow rate decreases due to the generation of differential pressure during filtration. If the fineness is more than 10 mu m, the filtration efficiency may decrease due to the decrease in porosity . If the average pore diameter is less than 1 占 퐉, the average pore diameter of the nonwoven fabric after calendering becomes too small to cause a significant decrease in the flow rate. If the average pore diameter exceeds 20 占 퐉, the average pore diameter of the calendered non- Or the removal performance of the organic compound may be reduced.

The MB nonwoven fabric before calendering has an average thickness of 0.1 mm to 2 mm and the MB nonwoven fabric before calendering has a basis weight of 80 g / m2 to 400 g / m2, preferably 100 g / m2 to 350 g / M < 2 >.

In the present invention, the MB nonwoven fabric may be a modified MB nonwoven fabric to increase the bondability between the nonwoven fabric and the positive charge coating agent.

The modified MB nonwoven fabric is prepared by pretreating the surface and interior of the MB nonwoven fabric with a modifier to prepare a modified MB nonwoven fabric. And drying the modified MB nonwoven fabric.

The modifier for the step of preparing the modified MB nonwoven fabric may include a polymer resin containing an acrylic polymer resin and / or a polyvinyl alcohol resin; And a solvent.

The polymer resin, which is one of the modifier compositions, preferably has a weight average molecular weight of 1,800 to 200,000, preferably a weight average molecular weight of 1,800 to 150,000, more preferably 1,900 to 120,000. In this case, If the weight average molecular weight is more than 200,000, the coating may be uneven when the positive charge coating is carried out with the amine-based polymer solution, and the nonwoven fabric pores may be blocked It may be preferable to use a polymer resin having a weight average molecular weight within the above range because there is a possibility that the performance may deteriorate as the porosity decreases.

 The modifier may be a mixture of one or more selected from polyacrylic acid and polyvinyl alcohol, or preferably polyacrylic acid. The polymer resin may be used in an amount of 0.1 to 5% by weight, preferably 0.5 to 3% by weight, more preferably 0.5 to 2% by weight, based on the total weight of the modifier. In this case, %, The coating strength of the positive charge coating layer may be lowered due to insufficient modification of the nonwoven fabric. If the amount of the charge control agent is more than 5% by weight, the pH of the modifier may be increased to partially dissolve the nonwoven fabric. Since the positive charge coating layer may be non-uniformly formed, it is preferable to use it within the above range.

Among the modifier components, the solvent may be a mixture of one or more of C1-C3 alcohol, acetone, and water, preferably C1-C3 alcohol and water, And mixtures thereof. More preferably, one or two or more selected from methanol and water can be mixed and used. The amount of the solvent used is 95 to 99.9% by weight, which is a relative amount of the acrylic polymer resin to be used.

The step of preparing the modified MB nonwoven fabric preferably comprises immersing the MB nonwoven fabric in a modifier at 10 ° C to 35 ° C for 5 seconds to 5 minutes, preferably at the above temperature for 10 seconds to 2 minutes If the immersion time is less than 5 seconds, the modification time is too short, so that the pore size (or pore size) inside the MB nonwoven fabric may not be sufficiently modified. Even if the immersion time exceeds 5 minutes, to be.

When the modified MB nonwoven fabric is dried, the drying method and the drying time can be generally used in the art. Preferably, the MB nonwoven fabric is sufficiently dried at 25 ° C to 120 ° C for 30 seconds to 12 hours .

In the method for producing a multifunctional porous separation membrane of the present invention, the positive charge coating agent in the positive charge coating treatment step may be a solvent; A crosslinking agent; And a multifunctional amine-based polymer resin.

Among the components of the positive charge coating agent, at least one selected from the group consisting of diethylene glycol, dimethylacetamide, dimethylformamide, N-methyl-2-pyrrolidone, ethanol, isopropyl alcohol, acetone and methanol may be used. , At least one selected from the group consisting of diethylene glycol, ethanol, isopropyl alcohol, acetone and methanol may be used, and more preferably one or two or more selected from diethylene glycol, ethanol and acetone may be mixed and used .

The polyfunctional amine-based polymer resin of the positive charge coating agent component serves to impart an electrostatic property to the exterior showing a positive charge, and may be one selected from the group consisting of polyethyleneimine, diethylenetriamine, piperazine, dimethylenepiperazine and diphenylamine Or a mixture of two or more of them may be used, and one or two or more selected from diethylenetriamine and diphenylamine may be used in combination. The amount to be used may be 0.3 to 8 parts by weight, preferably 0.3 to 5 parts by weight, more preferably 0.3 to 4 parts by weight, based on 100 parts by weight of the solvent. There may be a problem that a positive-positive coating layer is not formed to a sufficient thickness on the MB non-woven fabric. If the amount is more than 8 parts by weight, the pore size of the porous separation membrane may be narrowed and the thickness of the coating layer may unnecessarily increase, It is recommended to use it within the range.

And wherein the crosslinking agent is selected from the group consisting of bisphenol A epoxy resin, bisphenol F epoxy resin, hydrogenated bisphenol A epoxy resin, hydrogenated bisphenol F epoxy resin, flame retardant epoxy resin and novolac epoxy resin At least one selected from the group consisting of a bisphenol A epoxy resin and a novolak type epoxy resin can be used, and more preferably, a novolak type epoxy resin can be used.

The crosslinking agent may be used in an amount of 0.1 to 5 parts by weight, preferably 0.2 to 4 parts by weight, more preferably 0.3 to 2.5 parts by weight, based on 100 parts by weight of the solvent. In this case, , The bonding strength of the multifunctional amine-based polymer resin to the MB nonwoven fabric may be deteriorated, and even if the amount of the multifunctional amine-based polymer resin exceeds 5 parts by weight, there is no increase in bonding strength of the multifunctional amine-based polymer resin.

In the method for producing a multifunctional porous separation membrane of the present invention, the coating treatment method of the positive charge coating treatment step may be carried out using a general coating method used in the art such as dip coating and spray coating, At 60 占 폚 for 1 minute to 60 minutes. When the MB nonwoven fabric is coated with a positive charge coating agent by precipitation, the precipitation is carried out at a temperature of 10 ° C to 35 ° C for 10 seconds to 30 minutes, preferably 10 seconds to 10 minutes, more preferably 10 seconds to 5 minutes It is better to perform about a minute. If the immersion time is less than 10 seconds, the coating time is too short to sufficiently form the coating layer to the pores (or pores) in the MB nonwoven fabric, and it is uneconomical to exceed 30 minutes.

In the method for producing a multifunctional porous separator according to the present invention, the thermal crosslinking in the step of forming a positive charge-transporting coating layer is carried out at a temperature of 50 ° C to 130 ° C, preferably 50 ° C to 100 ° C, more preferably 60 ° C to 100 ° C If the thermal crosslinking temperature is less than 50 ° C, the coating layer is unevenly formed and the surface charge of the prepared porous separator is less than 10 mV, which is sufficient If the temperature is higher than 130 ° C, the nonwoven fabric may be thermally deformed and the pores of the porous separator may be narrowed to adversely affect the water permeation amount. Therefore, thermal crosslinking . The heat crosslinking time varies depending on the heat crosslinking temperature. It is preferable that the heat crosslinking time is preferably about 1 minute to 3 hours, preferably about 5 minutes to 2 hours.

If the average thickness of the positive charge transport layer is less than 0.1 탆, there may be a problem in that the uniformity of the coating layer is reduced due to a variation in the physical properties of the positive charge transport layer. When the average thickness exceeds 0.3 탆, the pore size of the porous separation membrane can be prevented. Therefore, it is preferable to form a positive charge coating layer so as to have the average thickness.

In the present invention, the calendering step may be carried out by applying a pressure of 1 kgf / cm 2 to 5 kgf / cm 2 to a pressure of 1 kgf / cm 2 to 5 kgf / cm 2 using a roller of 35 ° C to 130 ° C, preferably 70 ° C to 120 ° C, Is calendered by rolling at a rate of 1 mpm to 4 mpm, preferably 1 mpm to 3 mpm, preferably at a rate of 1 kgf / cm 2 to 3 kgf / cm 2 . If the roller pressure is less than 1 kgf / cm < 2 >, there is a problem that the effect of calendering can not be obtained because heat transfer does not occur inside the nonwoven fabric. If the pressure exceeds 5 kgf / There may be a problem. If the rolling speed is less than 1 mpm, there may be a problem that the heat transfer is uneven and the deviation of the physical properties increases. If the rolling speed exceeds 4 mpm, the heat transfer time is short and the effect of the reforming may be canceled.

Thus, the calendered MB-calendering nonwoven fabric has an average thickness of 0.05 mm to 1.5 mm, preferably an average thickness of 0.1 mm to 1.2 mm. If the average thickness of the MB-calendering nonwoven fabric is less than 0.05 mm, there is a problem that the pore diameter is greatly reduced and differential pressure is generated. If the average thickness is more than 1.5 mm, the change in pore diameter is not large, .

The MB-calendering nonwoven fabric may have an average pore size of 0.5 to 15 탆, preferably 1 to 10 탆. If the average pore size is less than 0.5 탆, the water permeation amount and the cumulative flow amount may be reduced , And when the average pore size exceeds 15 탆, the calendering effect is not so large, and the performance is not improved.

The calendered MB-calendering nonwoven fabric has a basis weight of 75 g / m 2 to 350 g / m 2, preferably 80 g / m 2 to 300 g / m 2. If the basis weight of the MB-calendering nonwoven fabric is less than 75 g / m < 2 >, a differential pressure may be generated and durability may deteriorate. If the basis weight exceeds 350 g / m < 2 >, bending during module manufacture is difficult. There is a problem that the effective film area is reduced.

The multifunctional porous separation membrane of the present invention thus prepared comprises a meltblown-calendering nonwoven fabric having a positive charge coating layer formed therein, and the positive charge coating layer contains a cross-linking agent and a polyfunctional amine compound.

The multifunctional porous separator of the present invention may have a surface charge of 10 mV to 40 mV, and preferably 15 mV to 35 mV. This is because the surface charge of the separator exhibits a positive charge, so that viruses, organic contaminants, colloids, etc. having a negative charge can be adsorbed and collected. If the surface charge of the porous separator is less than 10 mV, And the adsorption capacity for contaminants is similar even if it exceeds 40 mV, but there may be a problem that the production cost is increased due to the increase of the reaction time and concentration to exhibit a high surface charge in the process.

The surface electric charge can be measured based on a method calculated by the following Equation 1 by measuring the flow electric potential using a Surpass model manufactured by Anton Parr. However, the present invention is not limited thereto.

[Equation 1]

Where ζ is the zeta potential (mV), U is the streaming potential (p), η is the electrolyte viscosity, ε is the basic permittivity of the electrolyte, ε ₀ is the dielectric constant of the electrolyte, K _b : Electrical conductivity of electrolyte

The porous membrane of the present invention may have an average water permeation rate of 25 to 150 ml / cm ² · min · bar, preferably 30 to 100 ml / cm ² · min · bar.

The multifunctional porous separation membrane of the present invention having a high surface charge and an average water permeation amount can have a virus removal performance of 2.5 log or more, preferably 3 log or more, and more preferably 3.5 log or more. The humic acid removal performance may be 80% or more, preferably 80% to 99.9%, and more preferably 82 to 99.5%.

The multifunctional porous separation membrane of the present invention preferably has a cumulative amount of purified water of 2,000 L to 3,800 L, preferably 2,100 L to 3,400 L, more preferably 2,000 to 3,000 L, when measured based on a constant pressure permeation method of 1 bar of tap water using an effective membrane area of 0.1 m 2 It can have between 2,500 L and 3,200 L.

Also, the multifunctional porous separation membrane of the present invention can be manufactured in a laminated form of one layer or two to three layers. The multifunctional porous separation membrane of the present invention can be produced by using a spun-bonded nonwoven fabric as a support . ≪ / RTI >

The multifunctional porous separation membrane of the present invention can be used as a pretreatment filter for a water treatment process such as reverse osmosis (RO) to effectively remove viruses, organic contaminants, and the like that cause fouling, Can be increased.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the following examples should not be construed as limiting the scope of the present invention, and should be construed to facilitate understanding of the present invention.

[ Example ]

Example  1: formed with positive charge coating layer MB Production of nonwoven fabric

99% by weight of water and 1% by weight of polyacrylic acid having a weight average molecular weight of 18,000 were mixed to prepare a modifier.

Next, a polypropylene meltblown nonwoven fabric having an average pore size of 6.5 mu m, an average fineness of 3.5 mu m and an average thickness of 702 mu m was immersed in the modifier at 25 DEG C for 30 seconds, and then taken out of the modifier, followed by sufficiently drying at 80 DEG C for 3 minutes, To prepare a meltblown nonwoven fabric.

Next, the amorphous polymer solution containing 99 wt% of water and 1 wt% of polyethyleneimine was immersed in the modified nonwoven fabric at 25 DEG C for 30 seconds.

Next, the non-woven fabric having the coatings immersed therein was hot-air-treated at 80 ° C for 10 minutes to perform thermal crosslinking treatment to form a positive charge coating layer having an average thickness of 0.12 μm on the inside and the surface of the nonwoven fabric.

1 shows an SEM measurement photograph of a polypropylene nonwoven fabric before reforming, and FIG. 2 shows an SEM photograph of an antiviral filter material produced by heat crosslinking treatment. Comparing FIG. 1 and FIG. 2, it was confirmed that a positive-positive coating layer is well formed on the inner fibers of the polypropylene MB non-woven fabric.

Example  2

An MB nonwoven fabric in which a positive charge transport layer was formed was prepared in the same manner as in Example 1, except that polyacrylic acid among the modifier components having a weight average molecular weight of 1,900 was used.

Example  3

An MB nonwoven fabric in which a positive charge transport layer was formed was prepared in the same manner as in Example 1, except that polyacrylic acid among the modifier components having a weight average molecular weight of 120,000 was used.

Example  4

Except that 2% by weight of polyacrylic acid having a weight average molecular weight of 18,000 was used as the modifier component, to prepare an MB nonwoven fabric having a positive charge coating layer formed thereon.

Example  5

Except that an amine-based polymer solution containing 3% by weight of polyethyleneimine was used in place of the amine-based polymer solution prepared in Example 1, to thereby prepare an MB nonwoven fabric having a positive charge coating layer formed thereon.

Example  6

An MB nonwoven fabric having a positive charge coating layer formed thereon was prepared in the same manner as in Example 1 except that the thermal crosslinking temperature and time were changed to 110 캜 for 5 minutes.

Example  7

The same procedure as in Example 1 was carried out to prepare an antiviral filter medium and a polypropylene nonwoven fabric was used in the same manner as in Example 1 except that polypropylene nonwoven fabric having an average pore size of 15 μm, a fineness of 7 μm and an average thickness of 650 μm was used To prepare an MB nonwoven fabric having a positive charge coating layer formed thereon.

Example  8

Except that a polypropylene MB nonwoven fabric having a basis weight of 100 g / m 2, an average pore size of 6.2 탆, a fineness of 3.5 탆 and an average thickness of 700 탆 was used as the polypropylene MB nonwoven fabric in the same manner as in Example 1 , An MB nonwoven fabric having a positive charge coating layer formed thereon was prepared.

Comparative Example  One

An MB nonwoven fabric in which a positive charge transport layer was formed was prepared in the same manner as in Example 1, except that polyacrylic acid among the modifier components was used having a weight average molecular weight of 450,000.

Comparative Example  2

The MB nonwoven fabric in which the positive charge coating layer was formed was prepared in the same manner as in Example 1, except that the thermal crosslinking temperature and time were 2 hours at 40 캜.

Comparative Example  3

Except that 10% by weight of polyacrylic acid having a weight average molecular weight of 18,000 was used as the modifier component, to thereby prepare an MB nonwoven fabric having a positive charge coating layer formed thereon.

Comparative Example  4

An amine based polymer solution containing 98 wt% of water, 1 wt% of polyacrylic acid having a weight average molecular weight of 18,000, and 1 wt% of polyethyleneimine was prepared.

Next, the same nonwoven fabric as in Example 1 was immersed in the amine-based polymer solution at 25 DEG C for 30 seconds.

Next, the non-woven fabric on which the coating material was immersed was hot-air-treated at 80 ° C for 10 minutes to perform thermal crosslinking treatment to produce an MB nonwoven fabric having a positive charge coating layer formed thereon.

Comparative Example  5

Except that a polypropylene nonwoven fabric having an average pore size of 50 mu m, an average fineness of 15 mu m and an average thickness of 989 mu m was used as the polypropylene nonwoven fabric, except that a polypropylene nonwoven fabric having a positive charge coating layer formed thereon was used Example 1 An MB nonwoven fabric in which a positive charge coating layer was formed was prepared in the same manner.

Comparative Example  6

An MB nonwoven fabric in which a positive charge transport layer was formed was prepared in the same manner as in Example 1 except that thermal crosslinking temperature and time were thermally crosslinked at 145 캜 for 2 hours.

division MB nonwoven fabric
Average thickness
(탆) MB nonwoven fabric
Average fineness
(탆) MB nonwoven fabric
Basis weight (g / ㎡) MB nonwoven fabric
Average pore size
(탆) Coating layer
Whether uniform formation Coating layer
Average thickness
(탆) Example 1 702 3.5 300 6.5 Uniformity 0.20 Example 2 704 3.5 300 6.4 Uniformity 0.21 Example 3 700 3.5 300 6.5 Uniformity 0.18 Example 4 703 3.5 300 6.6 Uniformity 0.23 Example 5 702 3.5 300 6.4 Uniformity 0.22 Example 6 705 3.5 300 6.5 Uniformity 0.19 Example 7 650 7 300 15 Uniformity 0.22 Example 8 700 3.5 100 6.2 Uniformity 0.22 Comparative Example 1 701 3.5 300 4.3 Unevenness 0.46 Comparative Example 2 702 3.5 300 6.4 Unevenness 0.12 Comparative Example 3 705 3.5 300 5.2 Unevenness 0.36 Comparative Example 4 706 3.5 300 7.5 Uniformity 0.05 Comparative Example 5 989 15 300 50 Uniformity 0.23 Comparative Example 6 702 3.5 300 5.5 Unevenness 0.19

In Table 1, it can be seen that in the case of Examples 1 to 7, the positive charge coating layer was uniformly formed to a thickness of 0.1 탆 to 0.3 탆 overall.

However, in Comparative Example 1 using polyacrylic acid having a weight average molecular weight of 450,000 as a modifier component, the average pore size of the MB nonwoven fabric was reduced, the coating layer was formed nonuniformly, and the pore size of the nonwoven fabric became too small There was a problem.

In the case of Comparative Example 2 in which the thermal crosslinking was performed at less than 50 캜, there was a problem that the coating layer was unevenly formed. In the case of Comparative Example 3 in which 10 wt% of polyacrylic acid as a modifier component exceeding 5 wt% was used, the pH was high and the MB nonwoven fabric was partially dissolved, and the positive charge coating layer was formed thick, but the positive charge coating layer was formed non- And the pores of a part of the nonwoven fabric are blocked.

In the case of Comparative Example 4 in which polyacrylic acid as a modifying component and polyethyleneimine as a coating component were simultaneously coated, the coating layer was uniformly formed, but the coating layer was too thin, and the coating layer was not well fixed to the MB nonwoven fabric There was a problem that I could not do.

In the case of Comparative Example 6 in which the thermal crosslinking temperature was higher than 130 占 폚, there was a problem that the pore size of the MB nonwoven fabric was thermally deformed and the pore size became small in a part of the MB nonwoven fabric, and the coating layer was unevenly formed .

Manufacturing example  1: Preparation of Multifunctional Porous Membrane

The polypropylene MB nonwoven fabric formed with the positive charge coating layer prepared in Example 1 was subjected to calendering by applying a pressure of 2 kg / cm 2 with a roller at a temperature of 100 ° C under pressure to obtain an average thickness of 650 μm, A polypropylene meltblown-calendering nonwoven fabric (multifunctional porous separator) having a basis weight of 250 g / m 2 was prepared.

Manufacturing example  2 ~ Manufacturing example  6

Each of the MB nonwoven fabrics formed with the positive charge coating layers prepared in Examples 2 to 4 and Examples 7 to 8 was subjected to calendering in the same manner as in Production Example 1 to prepare MB-calendering nonwoven fabrics, 2 to Preparation Example 6 were carried out.

Manufacturing example  7

The same procedure as in Production Example 1 was carried out except that the polypropylene MB nonwoven fabric formed with the positive charge coating layer prepared in Example 1 was subjected to calendering by applying a pressure of 3 kg / Calendered nonwoven fabric (multifunctional porous separator) having an average pore size of 1.5 mu m and a basis weight of 230 g / m < 2 >

Comparative Manufacturing Example  One

The MB nonwoven fabric prepared in Example 1 was prepared as a multifunctional porous separator.

Comparative Manufacturing Example  2 ~ Comparative Manufacturing Example  3

Polypropylene meltblown-calendering nonwoven fabrics having physical properties as shown in Table 2 below were prepared by using each of the polypropylene MB nonwoven fabrics produced in Comparative Example 4 and Comparative Example 5, And Comparative Production Examples 2 to 3 were carried out.

Comparative Manufacturing Example  4

The same procedure as in Production Example 1 was carried out except that the polypropylene MB nonwoven fabric formed with the positive charge coating layer prepared in Example 1 was subjected to calendering by applying a pressure of 2 kg / To produce a polypropylene meltblown-calendering nonwoven fabric having the properties as shown in Fig.

Comparative Manufacturing Example  5

The same procedure as in Production Example 1 was carried out except that the polypropylene MB nonwoven fabric formed with the positive charge coating layer prepared in Example 1 was subjected to calendering by applying a pressure of 2 kg / To produce a polypropylene meltblown-calendering nonwoven fabric having the properties as shown in Fig.

Comparative Manufacturing Example  6

The same procedure as in Production Example 1 was carried out except that the polypropylene MB nonwoven fabric formed with the positive charge coating layer prepared in Example 1 was subjected to calendering by applying a pressure of 7 kg / A calendered nonwoven fabric (MB-calendering nonwoven fabric) having physical properties such as a tensile strength and a tensile strength was produced.

division Positive charge coating layer formed
MB Nonwoven Type roller
Temperature / pressure MB-Calendering
Non-woven
Average thickness (占 퐉) MB-calendaring nonwoven
Average pore size (탆) MB-calendaring nonwoven
Basis weight (g / ㎡) Production Example 1 Example 1 100 ° C /
2 kg / ㎠ 650 4 250 Production Example 2 Example 2 100 ° C /
2 kg / ㎠ 600 4 250 Production Example 3 Example 3 100 ° C /
2 kg / ㎠ 600 4.2 250 Production Example 4 Example 4 100 ° C /
2 kg / ㎠ 600 5 255 Production Example 5 Example 7 100 ° C /
2 kg / ㎠ 580 10 180 Production Example 6 Example 8 100 ° C /
3 kg / ㎠ 450 2.5 155 Production Example 7 Example 1 120 ° C /
3 kg / ㎠ 570 1.5 230 Comparative Preparation Example 1 Example 1 - 702 6.5 300 Comparative Preparation Example 2 Comparative Example 4 100 ° C /
2 kg / ㎠ 694 7.1 290 Comparative Production Example 3 Comparative Example 5 100 ° C /
2 kg / ㎠ 918 4.2 285 Comparative Production Example 4 Example 1 30 ° C /
2 kg / ㎠ 702 6.5 300 Comparative Preparation Example 5 Example 1 140 ° C /
2 kg / ㎠ 542 0.1 98 Comparative Preparation Example 6 Example 1 100 ° C /
7 kg / ㎠ 480 0.2 125

Experimental Example  One

The basic properties of the porous separator prepared in Preparation Examples 1 to 8 and Comparative Preparation Examples 1 to 6 were measured as follows. The results are shown in Table 3 below.

(1) Virus Removability  evaluation

(MS2 phage) solution diluted to 8 x 10 < ⁵ > / ml in PFU / ml (PFU: plaque forming units) at a constant pressure of 1 bar through a sample holder having a diameter of 90 mm To evaluate microbial removal performance. The results are shown in Table 3 below.

(2) Humic acid Removability  evaluation

The membrane was passed through a sample holder having a diameter of 90 mm at a flow rate of 2.0 LPM at a flow rate of 20 ppm of humic acid, and the concentration before and after permeation was measured by UV absorbance measurement.

(3) Cumulative water quantity evaluation

As the porous separator initial 1.9 to 24 hours with tap water 2.2L / min water flow rate, the introduction of ^{1 × 10 4 ~ 1 × 10} 5 can be prepared containing 20ppm humic acid of the virus and the PFU / ㎖ 1L every 6 hours, The accumulated amount of purified water was measured.

The cumulative amount of purified water is measured as the total amount of purified water at the same time and hydraulic pressure. Increasing the treatment flow rate of the porous separation membrane means that the use period of the separation membrane is increased.

 (4) Evaluation of average permeability

Flat membrane evaluator (manufactured by Toray Chemical Co., Ltd.) - RO water was permeated through a sample holder having a diameter of 90 mm under a constant pressure of 1 bar to quantitatively determine the permeability of the permeated water.

division Surface charge
(mV) virus
Removal performance (log) Humic acid
Removal performance
(%) Initial flow
(L) Accumulated water quantity
(L) Average permeability
(Ml / cm ² ? In? Ar) Production Example 1 35 4.3 88.2 2.1 3,800 40 Production Example 2 18 3.8 86.5 2.2 3,650 52 Production Example 3 33 5.1 87 2.1 3,430 49 Production Example 4 35 5.2 93 2.0 2,300 32 Production Example 5 28 4.1 99.5 1.9 2,000 25 Production Example 6 34 4.9 94 1.9 2,500 72 Production Example 7 35 5.8 83 2.0 2,700 58 Comparative Preparation Example 1 35 3.7 82.8 2.0 1,950 74 Comparative Preparation Example 2 15 0.7 28 2.1 990 24 Comparative Production Example 3 28 1.2 67 2.0 12,300 197 Comparative Production Example 4 28 3.8 84 1.9 1,400 25 Comparative Preparation Example 5 38 4.9 88.3 2.0 1,050 27 Comparative Preparation Example 6 42 5.7 99.8 2.0 1,250 23

As can be seen from Table 1, the virus removal performance of the porous separation membranes of Production Examples 1 to 7 was superior to 2.5 log or more, preferably 2.6 log to 4.3 log depending on the production conditions of the antiviral nonwoven fabric, The humic acid removal performance was 80% or more, preferably 82% or more. The porous separation membranes of Production Examples 1 to 7 each had an average water permeation rate of 25 to 72 ml / cm ² · min · bar and a cumulative purified water volume of 2,000 L to 3,800 L, .

However, the MB nonwoven fabric of Comparative Example 1 in which calendering was not performed showed lower virus removal performance and humic acid removal performance than Example 1.

In Comparative Preparation Example 2, which was produced using MB nonwoven fabric of Comparative Example 4, which was prepared by coating both polyacrylic acid as a modifying component and polyethyleneimine as a coating component, the coating layer was formed to be too thin, There was a problem that it was not fixed to the MB nonwoven fabric, resulting in poor virus removal performance and humic acid removal performance.

In Comparative Preparation Example 3 prepared using MB nonwoven fabric having an average thickness of 989 占 퐉 in Comparative Example 5, there was no increase in the virus and humic acid removal performance as compared with Example 1, and the average water permeation amount tended to decrease .

 In Comparative Preparation Example 4 produced by calendering at a roller temperature that is too low, calendering was not effectively performed, and the virus removal performance and humic acid removal performance were lower than those of Example 1.

In Comparative Production Example 5 using a roller having a high temperature of 140 캜 and Comparative Production Example 6 in which calendering was carried out by applying a roller pressure of 7 kg / cm 2, although the virus and humic acid removal performance was excellent, The flow rate was decreased rapidly.

It was confirmed that the porous separator of the present invention has excellent water permeation amount, cumulative purified water amount, virus removal performance and organic pollutant (humic acid) removal performance through the above Examples and Experimental Examples, It is confirmed that the present invention is suitable for use as a pretreatment filter for water treatment such as an RO pre-treatment filter.

Claims (19)

Calendered nonwoven fabric obtained by calendering a meltblown nonwoven fabric having a positive charge coating layer formed on the inside and the surface of the nonwoven fabric,
The meltblown nonwoven fabric may include at least one selected from polypropylene fibers, polyethylene terephthalate fibers, polyethylene fibers, polyester fibers, nylon fibers and cellulose fibers,
Wherein the positive charge transport layer comprises a crosslinking agent and a polyfunctional amine compound.
The meltblown nonwoven fabric according to claim 1, wherein the meltblown nonwoven fabric has a fineness of 0.5 탆 to 10 탆, an average pore diameter of 1 탆 to 20 탆 and a basis weight of 80 g / m 2 to 400 g / An average pore diameter of 0.5 to 15 m and a basis weight of 75 g / m < 2 > to 350 g / m < 2 >.
The multifunctional porous separator according to claim 1, wherein the meltblown nonwoven fabric has an average thickness of 0.1 mm to 2 mm and the meltblown calendering nonwoven fabric has an average thickness of 0.05 mm to 1.5 mm.
The epoxy resin composition according to claim 1, wherein the crosslinking agent is selected from the group consisting of bisphenol A epoxy resin, bisphenol F epoxy resin, hydrogenated bisphenol A epoxy resin, hydrogenated bisphenol F epoxy resin, flame retardant epoxy resin and Novolac epoxy resin A resin,
Wherein the polyfunctional amine compound comprises at least one selected from the group consisting of polyethyleneimine, diethylenetriamine, piperazine, dimethylenepiperazine, and diphenylamine.
The multi-functional porous separator according to claim 1, wherein the positive-electrode coating layer has an average thickness of 0.01 탆 to 1 탆.
The multi-functional porous separator according to claim 1, wherein the porous separator has a surface charge of 10 mV to 40 mV.
The nonwoven fabric according to claim 1, wherein the meltblown nonwoven fabric comprises
0.1-5 weight of a polymer resin containing at least one selected from polyacrylic acid having a weight average molecular weight of 1,800 to 200,000 and polyvinyl alcohol having a weight average molecular weight of 1,800 to 200,000; And 95 to 99.9% by weight of a solvent containing at least one of C1 to C3 alcohol, acetone and water.
The multifunctional porous separator according to any one of claims 1 to 7, wherein the average water permeation amount is 25 to 150 ml / cm ² · min · bar and the cumulative purified water amount is 2,000 to 3,800 L.
9. The method of claim 8,
Wherein the virus removal performance is 2.5 log or more and the humic acid removal performance is 80% to 99.9%.
Treating the meltblown nonwoven fabric with a positive charge coating agent;
Forming a positive charge coating layer on the meltblown nonwoven fabric by heat crosslinking the nonwoven fabric subjected to positive charge coating; And
Calendering a meltblown nonwoven fabric having a positive charge coating layer formed thereon;
Wherein the porous separator is a porous membrane.
11. The nonwoven fabric according to claim 10, wherein the meltblown nonwoven fabric is a modified meltblown nonwoven fabric,
The modified meltblown nonwoven fabric may be prepared by pretreating the surface and interior of the nonwoven fabric with a modifier to produce a modified meltblown nonwoven fabric. And drying the modified melt blown nonwoven fabric. The method of manufacturing a multi-functional porous separation membrane according to claim 1,
12. The method of claim 11, wherein the modifier comprises
0.1-5 weight of a polymer resin containing at least one selected from polyacrylic acid having a weight average molecular weight of 1,800 to 200,000 and polyvinyl alcohol having a weight average molecular weight of 1,800 to 200,000; And
And 95 to 99.9% by weight of a solvent containing at least one of C1-C3 alcohol, acetone and water.
The process for producing a modified melt blown nonwoven fabric according to claim 11, wherein the step of preparing the modified melt blown nonwoven fabric is performed by immersing the melt blown nonwoven fabric in the modifier at 10 ° C to 35 ° C for 5 seconds to 5 minutes Way.
The method of claim 10, wherein the coating is performed by immersing the meltblown nonwoven fabric in the positive charge coating agent at 10 ° C to 35 ° C for 10 seconds to 30 minutes.
11. The method of claim 10, wherein the thermal crosslinking treatment is performed at 50 DEG C to 130 DEG C for 1 minute to 3 hours.
11. The method of claim 10, wherein the positive charge coating agent comprises
A solvent containing at least one member selected from the group consisting of diethylene glycol, dimethylacetamide, dimethylformamide, N-methyl-2-pyrrolidone, ethanol, isopropyl alcohol, acetone, and methanol;
A crosslinking agent containing at least one selected from the group consisting of bisphenol A epoxy resin, bisphenol F epoxy resin, hydrogenated bisphenol A epoxy resin, hydrogenated bisphenol F epoxy resin, flame retardant epoxy resin and novolak epoxy resin; And
A polyfunctional amine compound containing at least one member selected from the group consisting of polyethyleneimine, diethylenetriamine, piperazine, dimethylenepiperazine and diphenylamine;
Wherein the porous separator is a porous membrane.
17. The method of claim 16, wherein 0.1 to 5 parts by weight of the crosslinking agent and 0.3 to 8 parts by weight of the polyfunctional amine compound are added to 100 parts by weight of the solvent.
11. The method of claim 10, wherein the calendering of the step of calendering
Calendering is carried out by rolling a meltblown nonwoven fabric having a positive charge coating layer at a speed of 1 mpm to 4 mpm while applying a pressure of 1 kgf / cm 2 to 5 kgf / cm 2 with a roller at 35 ° C to 130 ° C Wherein the porous separator is a porous membrane.
A reverse osmosis (RO) pretreatment filter comprising the multifunctional porous separation membrane of claim 9.

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