JP3293945B2 - Porous adsorbent - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a use for removing, recovering or concentrating a substance dissolved in water by adsorption.
For example, the present invention relates to a porous adsorbent useful in fields such as wastewater treatment, the chemical industry, the food industry, and the dyeing industry.

[0002]

2. Description of the Related Art Heretofore, there has been known a method of removing, recovering, or concentrating a substance dissolved in water by adsorbing the same, and inorganic substances such as activated carbon and zeolite have been often used as an adsorbent. However, generally speaking, it has been quite difficult to selectively adsorb a specific substance and to control the adsorbing power for desorbing and recovering the substance adsorbed by the adsorbent. Certainly, although the control of the activity of activated carbon, the control of acidity / basicity, and the control of the pore size of zeolite were performed, the selectivity of adsorption was still insufficient. The selective adsorptivity for the substance was very poor.

[0003]

The present inventors have developed a method for selectively adsorbing a substance dissolved in water, particularly a method for selectively adsorbing a medium or high molecular weight substance such as a polymer or a dye.
Further, the present inventors have made intensive studies on a method for controlling the strength of absorption and desorption, and have reached the present invention.

[0004]

That is, the gist of the present invention is to provide a porous adsorbent comprising a polymer containing (meth) acrylate as a main component and having a contact angle with water of 45 to 110 °.
And a pore diameter of 0.0005 to 0.0 formed on the surface.
1 μm dense layer portion and pore diameter 0.002 formed inside
A porous adsorbent comprising a porous portion having a thickness of 10 to 10 μm . Hereinafter, the present invention will be described in detail.
The porous adsorbent of the present invention comprises a polymer of a monomer and / or an oligomer which is a (meth) acrylate ester.
It is composed of a polymer containing at least% by weight. Preferably, the polymer is a cross-linked polymer. That is, the polymer constituting the porous adsorbent of the present invention is preferably a polymer of a monomer and / or oligomer containing a monomer and / or oligomer having two or more functions.

[0005] The bifunctional or higher functional monomer and / or oligomer is preferably 2 to 6 functional. Examples of (meth) acrylate monomers that can be used in the present invention include ethyl (meth) acrylate, n-
Butyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, phenyl (meth) acrylate, phenyl cellosolve (meth) acrylate, isobornyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopen Monofunctional monomers such as teniloxyethyl (meth) acrylate,

Diethylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, polyethylene glycol di (meth) acrylate,
Bifunctional monomers such as 2,2'-bis (4- (meth) acryloyloxypolyethyleneoxyphenyl) propane and 2,2'-bis (4- (meth) acryloyloxypolypropyleneoxyphenyl) propane;

Trifunctional monomers such as trimethylolpropane tri (meth) acrylate and trimethylolethanetri (meth) acrylate, tetrafunctional monomers such as pentaerythritol tetra (meth) acrylate, and 6-functional monomers such as dipentaerythritol hexaacrylate And functional monomers. Of course, it is also possible to use a mixture of these monomers.

[0008] The oligomer used in the present invention includes:
For example, it is polymerizable by irradiation with energy rays and has a weight average molecular weight of 500 to 50,000. Specifically, for example, acrylate or methacrylate of epoxy resin, acrylate or methacrylate of polyether resin And acrylate or methacrylate of polybutadiene resin, and polyurethane resin having an acryl or methacryl group at a molecular terminal. Of course, these oligomers can be used as a mixture, or can be used as a mixture with a monomer.

(Meth) Constituting the Porous Adsorbent of the Present Invention
The acrylate ester is preferably a (meth) acrylate ester having an ethylene glycol unit in the molecule and having a repeating portion containing less than 9 ethylene glycol units, and the ethylene glycol unit has a molecular weight of 500.
It is preferable to contain one or more per unit. Alternatively, a urethane (meth) acrylate having at least one urethane bond per 600 molecular weight is preferable in order to exhibit excellent adsorption / desorption characteristics.

The monomers and / or oligomers for producing the porous adsorbent of the present invention include a hydrophilic group such as a hydroxyl group and an amide bond, a hydrophobic group such as fluorine and siloxane, an acid such as a carboxyl group and a sulfone group, and an amino acid. By appropriately mixing a monomer and / or an oligomer having a group, a base such as an ammonium salt, or a salt in the molecule, the adsorptive power and the selectivity can be adjusted.

The polymer of the present invention also has a contact angle with water of 4
The angle is 5 to 110 °, preferably 55 to 100 °, more preferably 60 to 90 °. The present inventors, even if the contact angle with water is larger or smaller than this value,
It has been found that the adsorptive power of medium-high molecular weight substances dissolved in water is weakened. Outside this range, the selectivity also decreases. The contact angle of the porous body with water is affected by the porous structure and may not accurately reflect the hydrophilicity of the polymer of the material. The contact angle with water of a polymer that is not porous but has a smooth surface. To measure the contact angle of a non-porous polymer with water, the same monomers and / or
Alternatively, it can be measured by using an oligomer to obtain a nonporous polymer by a usual polymerization / film-forming method.

The optimum contact angle varies depending on the type of the target substance to be adsorbed, the necessity of desorption, and the like. The adjustment of the contact angle is performed by selecting the type of monomer and / or oligomer, or by selecting the type of monomer and / or oligomer. By mixing a monomer and / or an oligomer having a hydrophilic group, a hydrophobic group, or the like in the molecule with the oligomer, it can be adjusted according to the use and purpose. Alternatively, it can be adjusted by polymerizing in the presence of a hydrophilic substance or a hydrophobic substance which does not participate in the polymerization.

The porous adsorbent of the present invention has pores communicating with each other, so-called communication holes. The size of the pores is not particularly limited, but it is preferable that the pore size distribution measured by a mercury porosimeter has a peak at 0.02 to 10 μm. If the pore size is too small, the substance to be adsorbed becomes the same as in the case of activated carbon or zeolite, and the characteristics of the present invention are lost. Becomes

The pore distribution in the depth direction of the porous adsorbent does not need to be particularly limited, and may be a so-called isotropic porous body in which the pore diameter is substantially uniform from the surface to the inside. And an anisotropic porous body having a different pore diameter inside. When the porous adsorbent of the present invention is used for selective adsorption of a polymer having a molecular weight, a pore size having a molecular weight fractionating property on the surface, that is, a pore size of 0.0005 to 0.0
A structure having a layer of 1 μm (referred to as a dense layer) and a porous body having a pore size of about 0.02 to 10 μm inside is also preferable.

[0015] Molecules or particles larger than the pore size of the dense layer cannot enter the porous body and are not substantially adsorbed. Although it is difficult to measure the pore size of the dense surface layer even with an electron microscope, it can be determined from the selective adsorption of the polymer. The pore diameter inside the anisotropic porous adsorbent can be measured by measuring the cut sample with a porosimeter.

[0016] The shape of the porous adsorbent of the present invention is particulate,
The shape may be fibrous, film-like, or any other shape, but is 0.05 to 5 mm in diameter, preferably 0.3 to 3 in diameter.
mm spherical shape, and a diameter of 0.01 to
It is preferably a fiber having a diameter of 1 mm, preferably 0.05 to 0.5 mm. The sphere does not need to be a true sphere, but need only be approximately spherical, and the fiber does not need to have a circular cross section, and may be a modified cross-section yarn. It is difficult to make the diameter of the sphere or fiber smaller than this value from the viewpoint of handleability, and if it is larger than this value, the absorption / desorption speed is reduced.

The method for producing the porous adsorbent of the present invention can employ any method. In the embodiment, a polymerizable solution mainly composed of a monomer and / or an oligomer and a phase separation agent is extruded from a nozzle into a gas, and the extruded polymerizable solution naturally falls in a fibrous form or a droplet form. By irradiating the polymerizable solution with energy rays.

When the monomer and / or oligomer undergoes a reaction inhibition by oxygen during polymerization by irradiation with energy rays, it is preferable to increase the polymerization rate by performing irradiation with energy rays in an inert gas atmosphere. Furthermore, when the monomer and / or oligomer undergoes a reaction inhibition by oxygen during the polymerization by energy ray irradiation, it is also preferable to increase the polymerization rate by removing oxygen dissolved in the polymerizable solution.

When the polymerizable solution is irradiated with energy rays,
The monomers and / or oligomers in the polymerizable solution are polymerized or cross-linked, and at the same time, phase-separate with the phase-separating agent, and aggregate and harden into a network or a shape of particles bonded to each other. That is, the porous body made of the polymer of the monomer and / or the oligomer is filled with the phase separation agent in the pores. Next, in a subsequent step, the phase separation agent is removed from the pores of the porous body. Any method such as washing, drying, suction and replacement can be employed for removing the phase separation agent.

After the removal of the phase separation agent, it is possible to further irradiate (after-cure) energy beams. After-curing can improve the strength and hardness of the porous body. It is also possible to perform a heat treatment after removing the phase separation agent. By the heat treatment, the unreacted monomer can be completely removed, the dimensional stability of the porous body can be imparted, and the pore diameter of the porous body can be adjusted.

The phase separating agent used in the present invention is compatible with the monomer and / or oligomer used in the present invention,
In addition, these monomers and / or oligomers are incompatible with the polymer produced upon irradiation with energy rays, and are substantially inert to energy rays.
In the present invention, the phase separation agent and the monomer and / or oligomer need to be substantially uniformly compatible at the time of energy ray irradiation. Irradiation with energy rays in a state in which phase separation has occurred results in the generation of large closed cells having a pore diameter of 10 μm or more, or the formation of a porous body.

Further, the compatibility between the phase separating agent and the monomer and / or oligomer may vary depending on the type of the monomer and / or oligomer. For example, a polyurethane resin having a (meth) acryl group at a molecular terminal as a polymerizable oligomer, or a (meth) acrylate ester having an ethylene glycol moiety in the molecule and having a repeating unit of less than 9 in a moiety containing an ethylene glycol unit When using, as a phase separation agent, methyl esters such as methyl caprate, ethyl caprate, methyl laurate, methyl caprylate, ethyl caprylate, diisobutyl adipate,

Dialkyl ketones such as diisobutyl ketone, alcohols, liquid polyethylene glycol, polyethylene glycol monoester, polyethylene glycol sorbitan esters, polyethylene glycol monoether, glycerin mono-, di- and triester, hydroxyl group Alkyl esters, alkylamines, polyethylene glycol amines having the above, and other surfactants can be suitably used.

Among them, liquid polyethylene glycol, polyethylene glycol monoester, polyethylene glycol sorbitan esters, polyethylene glycol monoether, glycerin mono-, di- and triesters, hydroxyl-containing alkyl esters, alkylamines, Alternatively, when polyethylene glycolamine or the like is used, the viscosity of the polymerizable solution can be increased without lowering the solubility of the monomer and / or oligomer. The polymer precipitated by the irradiation of the line is easily formed into a network, and the strength of the porous body is increased.

The phase separation agent that can be used in the present method is
Dissolved in the liquid monomer and / or oligomer,
A solid, for example, a polymer may be used as long as it is substantially inert to energy beam irradiation. For example, cellulose acetate, ethyl cellulose, nitrocellulose, chitosan, polystyrene, polyvinyl chloride, polycarbonate, polysulfone, polyethersulfone, polyurethane, polyacrylonitrile, polyacrylate, polyacrylic acid, polymethyl methacrylate, polyacrylamide, Examples thereof include polyethylene glycol, polyvinyl pyrrolidone, polyvinyl alcohol, and the like, and derivatives and copolymers thereof.

Among them, polyethylene glycol and polyvinylpyrrolidone are preferred. Of course, the polymer may be a plurality of polymers or a polymer solution. The phase separating agent may be a single composition or a mixture. In the case of a mixture, the properties of the components alone are not particularly limited. For example, individual components
The polymer may not be compatible with the monomer and / or oligomer and may not swell or dissolve the polymer, or may be compatible with the polymer generated from the monomer and / or oligomer. The phase-separating agent is formed by a method for producing a porous body, a kind of a monomer and / or an oligomer, a required viscosity of a polymerizable solution,
It can be appropriately selected depending on the solubility of the polymer and other additives, the pore size and the pore shape required for the porous body, and the like.

When producing an isotropic porous body, the phase separating agent is preferably a nonvolatile liquid. When the phase separation agent is a volatile liquid, a dense layer having a fine pore diameter is easily formed on the surface of the porous body. When ultraviolet rays are used as energy rays, those having low ultraviolet absorption are preferable.

The anisotropic porous material is obtained by (1) a method in which a volatile liquid is used as a phase separation agent, and a part of a good solvent is volatilized and then irradiated with an energy ray; (3) a method in which a polymerizable solution to which a good solvent (a solvent for swelling or dissolving a produced polymer) is added is extruded from a nozzle, and a part of the good solvent is volatilized and then irradiated with energy rays.
It can be produced by extruding a polymerizable solution from a nozzle at a high shear rate and irradiating with energy rays.

The ratio of the phase separating agent to the monomer and / or oligomer is preferably in the range of 0.1 to 4.0 parts by weight per 1 part by weight of monomer and / or oligomer. If it is 0.1 or less, the porosity of the porous body becomes too low, and if it is 4.0 or more, the strength of the porous body becomes insufficient. The pore size of the pores depends not only on the mixing ratio of the monomer and / or oligomer and the phase-separating agent, but also on the combination of the monomer and / or oligomer with the phase-separating agent. And the monomers and /
Or when the compatibility between the oligomer and the phase separation agent is poor,
When the viscosity of the polymerizable solution is low, the pore size increases.

The compatibility of the monomer and / or oligomer with the phase separation agent can be determined by gradually lowering the temperature of the mixture and at a temperature at which phase separation occurs. The lower the phase separation temperature, the better the compatibility. The polymerizable solution of the present invention,
In addition to monomers and / or oligomers and phase separators, it is also possible to contain other components, such as, for example, UV polymerization initiators. When ultraviolet rays are used as energy rays, it is preferable to include an ultraviolet polymerization initiator in the polymerizable solution for the purpose of increasing the polymerization rate.

The energy beam used in the production method of the present invention includes an electron beam, γ-ray, X-ray, ultraviolet ray, visible light and the like. Among them, ultraviolet rays are most preferable because of simplicity of equipment and handling. The intensity of the irradiated ultraviolet light is preferably 10 to 5000 mw / cm ² , and the exposure time is about 0.01 to 10 seconds. Electron beams are also preferable energy beams that can be used in the present invention. When an electron beam is used, it is not affected by the presence or absence of absorption of extraneous radiation such as a phase separating agent and other additives, so that the range of choice of the phase separating agent and the like is expanded. Further, since no polymerization initiator is required,
It is particularly preferred when this residue poses a problem.

[0032]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

[Example 1] (Preparation of polymerizable solution) V-4263 (Dainippon Ink Chemical Industry Co., Ltd.) as monomer and / or oligomer
80 parts of a urethane acrylate oligomer having an average molecular weight of about 2,000, an average of three acrylic groups in one molecule and an average of six urethane bonds (hereinafter all parts are indicated by weight) , BPE-4 (Shin Nakamura Chemical Co., Ltd.)
20 parts of ethylene oxide-modified bisphenol A diacrylate having a molecular weight of 512), 110 parts of methyl caprate and 50 parts of methyl laurate as phase separators, and Irgacure 65 as an ultraviolet polymerization initiator.
1 (manufactured by Ciba Geigy Co., Ltd., having 2,2-dimethoxy-2-phenylacetophenone as a main component) was mixed with 4 parts to obtain a polymerizable solution 1.

(Production of Porous Adsorbent) The polymerizable solution 1 was extruded from a nozzle having a diameter of 0.16 mm into the air at a rate of 22 ml / min by using a gear pump. Irradiates ultraviolet rays having a wavelength of 365 nm as a main component. The extruded polymerizable solution turned into droplets before entering the irradiation range, and a spherical polymer dropped from below the irradiation part. The white spherical polymer was washed with n-hexane and ethanol to obtain a white spherical porous body 1 having a diameter of about 0.47 mm. On the other hand, a transparent spherical polymer was obtained in the same manner as in this production method except that no phase separation agent was added.

(Measurement of Characteristics) This porous body was cut in half and observed with a scanning electron microscope (SEM).
Pores (voids) of about 0.3 μm were observed over the entire porous body. Further, when the porous body cut in half was measured with a mercury porosimeter (manufactured by Carlo Elba),
The peak of the pore size distribution was 0.35 μm.

On the other hand, in the transparent spherical polymer produced without adding a phase separating agent, no pore was observed in any part thereof by SEM observation, and no pore was present in the porosimeter measurement. , Non-porous. The contact angle of the non-porous body with water was 69 °.

(Adsorption test 1) 1.0 g of the porous body 1 was
To 50 ml of an aqueous solution of monodisperse polyethylene glycol (PEG) having an average molecular weight of 50,000 and having a concentration shown in Table 1, stirred for 4 hours, and then subjected to aqueous gel permeation chromatography (GPC) to determine the PEG concentration in the aqueous solution Was measured. Table 1 shows the results. The unit ppm in the table
Is ppm by weight (the same applies hereinafter). Up to the saturated adsorption amount of the porous adsorbent of about 5.8 mg / g, PE
It can be seen that the entire amount of G is adsorbed.

[0038]

[Table 1]

(Adsorption test 2) Average molecular weight 2000, 65
100 weight p of monodisperse polyethylene glycol (PEG) of 00, 18000, 50,000 and 150,000
To 50 ml of each aqueous solution of pm (hereinafter, weight ppm is simply referred to as ppm), 1.0 g of the porous body 1 was added and stirred for 4 hours. Table 2 shows the results. Molecular weight 2
PEG is hardly adsorbed and has a molecular weight of 5000.
All PEGs of 0 or more are adsorbed. That is, it is understood that there is a molecular weight selectivity of adsorption.

[0040]

[Table 2]

(Adsorption Test 3) A porous material having adsorbed 1.4 mg of PEG having an average molecular weight of 6500 in the same manner as in Test Example 2 was charged into 50 ml of a 100 ppm aqueous solution of PEG having an average molecular weight of 18000, and stirred for 15 hours. Thereafter, when the amount of PEG in the aqueous solution was measured, the average molecular weight was 6500.
Has a PEG concentration of 28 ppm (the total amount in 50 ml of the solution is 1.4 mg), and a PEG concentration of an average molecular weight of 18,000 is 3
It was 0 ppm, and the PEG having an average molecular weight of 6500 adsorbed on the porous material was completely desorbed. It can be seen that PEG having an average molecular weight of 6500 is removable.

(Adsorption test 4) 2.0 g of the porous body 1 was
100m aqueous solution of paraaminoazobenzene 100ppm
After stirring for 4 hours, the concentration of paraaminoazobenzene in the aqueous solution was measured by absorbance measurement. As a result, 98.2% of para-aminoazobenzene in the aqueous solution was adsorbed. When the porous body on which paraaminoazobenzene had been adsorbed was washed with ethanol, 95% of the adsorbed amount was desorbed.

(Adsorption test 5) 1.0 g of the porous body 1 was
100 ml of an aqueous solution of γ-globulin having a concentration described in Table 3
After stirring for 4 hours, the concentration of γ-globulin in the aqueous solution was measured by aqueous phase gel permeation chromatography (GPC). Table 3 shows the results.

[0044]

[Table 3]

(Adsorption test 6) 1.0 g of the porous body 1 was
100 m of an aqueous solution of bovine serum albumin having the concentration shown in Table 4
After stirring for 4 hours, the concentration of bovine serum albumin in the aqueous solution was measured by aqueous phase gel permeation chromatography (GPC). Table 4 shows the results.

[0046]

[Table 4]

(Adsorption Test 7) Ethanol, isopropanol and N, N-dimethylformamide were used as adsorption test substances, and 100 ml of a 100 ppm aqueous solution of each of these was used.
Then, 1.0 g of the porous body 1 was added thereto, and the mixture was stirred for 4 hours, and then the concentration in the aqueous solution was measured by GPC. As a result, the amount of these water-soluble substances adsorbed on the porous body is 0.1%.
mg / g or less.

[Example 2] (Production of porous adsorbent) The nozzle diameter was 0.5 mm, the extrusion amount of the polymerizable solution was 200 ml / min, and the range of 1 to 3 cm below the nozzle was About 200mw
Example 1 except that ultraviolet light having an intensity of / cm 2 was irradiated.
In the same manner as in the above, a porous fiber having a diameter of 0.45 mm was obtained.
Porosimetry of about 300 mg of the fiber cut into a length of about 1 cm confirmed that the fiber was a porous material having a peak at a pore diameter of 0.23 μm.

(Adsorption Test) A test similar to the adsorption test 1 of Example 1 was performed, and the results shown in Table 4 were obtained. The results are the same as those in the adsorption test 1 of Example 1 except that the saturated adsorption amount is slightly high.

[0050]

[Table 5]

Example 3 (Preparation of Polymerizable Solution) A mixture of 80 parts of V-4263 and 20 parts of 1,6-hexanediol diacrylate as monomers and / or oligomers, and polyethylene glycol sorbitan mono as a phase separating agent Laurate 7
0 parts, 30 parts of acetone as a solvent, and 4 parts of Irgacure 651 as an ultraviolet polymerization initiator were mixed to obtain a polymerizable solution 2.

(Preparation of Porous Adsorbent) The use of the polymer solution 2, the flow of nitrogen gas in the horizontal direction at a flow rate of 0.1 m / sec from 0 to 10 cm below the nozzle, and the use of the polymer solution A spherical porous body 3 having a diameter of 0.5 mm was obtained in the same manner as in Example 1 except that the extrusion amount was 44 ml / min. When this porous body 3 was observed by SEM, no pore was observed on the surface of the porous body 3 and the inside diameter was 0.5 μm.
Pores were observed. On the other hand, the contact angle with water of the non-porous film produced without using the phase separation agent was 75 °.

(Adsorption Test) A test similar to the adsorption test 2 of Example 1 was performed. Table 6 shows the results. It can be seen that the adsorptivity of the polymer having a small molecular weight and the polymer having a large molecular weight is low, and the adsorption has a molecular weight selectivity.

[0054]

[Table 6]

[Example 4] (Production of porous body) About 1 cm was also obtained in the range of 1 to 3 cm below the nozzle.
A fibrous porous body 4 having a diameter of 0.67 mm was obtained in the same manner as in Example 3 except that ultraviolet light having an intensity of 00 mw / cm 2 was irradiated. As a result of observing the porous fiber 4 with an SEM, no pore was observed on the surface of the fiber, and pores having a diameter of 0.2 μm were observed inside the fiber.

(Adsorption Test) A test similar to the adsorption test of Example 3 was performed, and the results shown in Table 7 were obtained. The results are similar to those of the adsorption test of Example 3 except that the adsorption amount is slightly high.

[0057]

[Table 7]

Example 5 (Preparation of Polymerizable Solution) BPE-4 (manufactured by Shin-Nakamura Chemical Co., Ltd., molecular weight 51) as a monomer and / or oligomer
70 parts of ethylene oxide-modified bisphenol A diacrylate (containing four ethylene glycol repeating units per molecule) as main components and 70 parts of calayat TPA330 (produced by Nippon Kayaku Co., Ltd. Oxide-modified trimethylolpropane triacrylate as a main component) 30 parts Methyl caprate 1 as a phase separator
Polymerizable solution 3 was obtained by mixing 10 parts, 50 parts of methyl laurate, and Irgacure 651 and 4 parts as an ultraviolet polymerization initiator.

(Preparation of Porous Adsorbent) The procedure of Example 1 was repeated except that the polymerizable solution 3 was used.
Thus, a spherical porous body 5 of m was obtained. This porous body 6 has 0.7
There was a peak in the pore size distribution at μm. On the other hand, the contact angle with water of a non-porous film produced using the same monomer and / or oligomer and without using a phase separator was 73 °.

(Adsorption Test) An adsorption test of PEG having a molecular weight of 50,000 was carried out in the same manner as in the adsorption test 1 of Example 1. The results were the same as those of the adsorption test 1 of Example 1.

Example 6 (Preparation of Polymerizable Solution) NK Ester BPE-200 (manufactured by Shin-Nakamura Chemical Co., Ltd., ethylene oxide-modified bisphenol A dimethacrylate (540) having a molecular weight of 540) was used as a monomer and / or oligomer. 80 parts mainly composed of 4 ethylene glycol repeating units in the molecule), 20 parts of 1,6-hexanediol diacrylate, 110 parts of methyl caprate and 50 parts of methyl laurate as phase-separating agents A polymerizable solution 4 was obtained by mixing 8 parts of Irgacure 651 as an ultraviolet polymerization initiator.

(Preparation of Porous Adsorbent) The procedure of Example 1 was repeated except that the polymerizable solution 4 was used.
Thus, a spherical porous body 6 of m was obtained. This porous body 6 has a thickness of 1.2
It had a peak in the pore size distribution at μm. On the other hand, the contact angle with water of a non-porous film produced using the same monomer and / or oligomer and not using a phase separator is 69 °.
Met.

(Adsorption test) An adsorption test of PEG having a molecular weight of 50,000 was carried out in the same manner as in the adsorption test 1 of Example 1. The results were the same as those of the adsorption test 1 of Example 1.

Comparative Example 1 This comparative example shows that a porous body made of another resin hardly adsorbs a polymer. (Production of porous body) A dope in which 15 parts of polysulfone (P-1800NT manufactured by Amoco Chemical Co., Ltd.) was dissolved in 85 parts of N, N-dimethylacetamide was extruded from a nozzle into water, and a white porous material having a diameter of about 0.5 mm was obtained. A quality fiber was obtained. SE
Observation with M revealed that pores of about 0.5 μm were present on the surface, and finger-like macropores having a diameter of 5 to 20 μm were present inside. On the other hand, the same dope was cast on a glass plate, and the solvent was volatilized by a hot air drier to obtain a non-porous film. The contact angle of this film with water was 57 °.

(Adsorption Test) An experiment similar to the adsorption test 1 of Example 1 was performed using a polysulfone porous fiber.
The amount of adsorption on the porous body was 0.1 mg /
g or less.

[Comparative Example 2] This comparative example shows that when the contact angle with water is less than 45 °, the polymer dissolved in water is hardly adsorbed. (Production of porous body) As a polymerization solution, 90 parts of BPE-4 as a monomer and / or oligomer and N
K-ester AM-90G (manufactured by Shin-Nakamura Chemical Co., Ltd., average molecular weight 454, methoxypolyethylene glycol 400 acrylate (monofunctional acrylate containing 9 continuous ethylene glycol units in one molecule)) Approximately 450 μm in diameter in the same manner as in Example 1 except that 10 parts were used.
Was prepared. On the other hand, the contact angle with water of the non-porous beads obtained using the same monomer and / or oligomer and without using a phase separating agent was 40 °.

(Adsorption test) When a test similar to the adsorption test 1 of Example 1 was performed, the amount of adsorption to the porous body was all 0.
It was 1 mg / g or less.

Comparative Example 3 This comparative example shows that when the contact angle with water exceeds 110 °, almost no polymer dissolved in water is adsorbed. (Production of porous body) 72 parts of V-4263, 18 parts of BPE-4 and 10 parts of Biscoat 8F (octafluoropentyl acrylate, manufactured by Osaka Organic Chemical Industry Co., Ltd.) as monomers and / or oligomers, and 10 parts of phase separator As methyl caprate 110 parts and methyl laurate 5
0 parts, Irgacure 651, 8 as UV polymerization initiator
Example 1 was repeated except that a polymerizable solution in which
In the same manner as in the above, a spherical porous body 7 having a diameter of about 0.5 mm was obtained. This porous body 7 had a pore size distribution peak at 0.72 μm. On the other hand, the contact angle with water of a non-porous film produced using the same monomer and / or oligomer and not using a phase separator was 115 °.

(Adsorption Test) When an experiment similar to the adsorption test 1 in Example 1 was performed, the amount of adsorption to the porous body was 0.1 mg / g or less in all cases.

[0070]

[Effect] The present invention is intended for selectively absorbing, collecting, removing or concentrating medium-high molecular weight substances such as polymers and dyes dissolved in water by controlling the strength of absorption and desorption, such as wastewater treatment. And a porous adsorbent useful in fields such as the chemical industry, the food industry, and the dyeing industry.

Claims (5)

(57) [Claims] (1) a contact angle with water is 45 to 110 °;
A porous adsorbent made of a polymer containing (meth) acrylic acid ester as a main component and having a pore size of 0.0005 to 0.01 μm formed on the surface.
Dense layer part, pore diameter formed inside 0.002 to 10 μm
A porous adsorbent characterized by comprising a porous part of: 2. The (meth) acrylate has one or more ethylene glycol units per 500 molecular weight,
The porous adsorbent according to claim 1, which is a (meth) acrylic acid ester having a number of repetitions of a portion containing an ethylene glycol unit of less than nine. 3. The porous adsorbent according to claim 1, wherein the (meth) acrylate is a urethane (meth) acrylate having at least one urethane bond per 600 molecular weight. 4. The porous adsorbent according to claim 1, wherein the pore distribution measured by a mercury porosimeter has a peak at 0.02 to 10 μm. 5. The method according to claim 1, which is a spherical porous body having a diameter of 0.05 to 5 mm or a fibrous porous body having a diameter of 0.05 to 1 mm .
4. The porous adsorbent according to any one of 3 .