JPWO2008078650A1 - Porous body and method for producing the same - Google Patents

Abstract

A step of heating a molded article of a composition containing a polymer substance, a pore-forming agent and a decomposable foaming agent to a temperature at which the polymer substance melts and foaming by decomposing the decomposable foaming agent; A method of producing a porous body comprising: extracting a pore-forming agent by dissolution in a solvent to form open cells in a molded product.

Description

  The present invention relates to a porous body and a method for producing the same.

  As a method for producing a porous body, for example, a resin and a volatile foaming agent such as carbon dioxide gas or ammonia gas are kneaded, and a kneaded product is foamed with a volatile gas or a decomposable foaming agent is kneaded with a resin and decomposed There is a method in which a kneaded product is foamed with a gas generated by decomposition of a mold foaming agent. Dispersing foaming agents include azodicarbonamide, dinitrosopentamethylenetetramine and hydrazodicarbonamide.

  In the case of these foaming methods, a closed-cell type foam is formed. Then, the method of obtaining the porous body in which the open cell was formed by adding a mechanical deformation | transformation to a foam and destroying a closed cell is proposed (refer patent document 1). However, with this method, it is difficult to destroy all closed cells, and it is difficult to obtain a porous body having a high ratio of open cells.

  Therefore, a method for obtaining a porous body by extracting a water-soluble powder from a molded product after melt-kneading a water-soluble powder having a melting point higher than that of the thermoplastic resin to obtain a molded product (hereinafter referred to as “extraction method”) Is known) (see Patent Document 2).

On the other hand, as a resin foam or a resin porous body to which various functions are added, for example, a composite foam filled with porous particles (Patent Document 3) or a resin porous body containing an inorganic hygroscopic agent (Patent Document 4). Proposed.
Japanese Patent Publication No.62-19294 JP 2002-322310 A JP 2002-1829 A JP 2002-191929 A

  However, in the above extraction method, if a large amount of water-soluble powder is used, the fluidity of the kneaded product is lowered in the molding step for obtaining a molded product, and the moldability tends to deteriorate or the appearance tends to deteriorate. . Therefore, it was practically difficult to obtain a porous body having a sufficiently high porosity by increasing the filling rate (mixing ratio) of the water-soluble powder.

  In addition, since bubbles are formed by extraction from a solid molded product in which bubbles are not substantially formed, it is necessary to extract water-soluble powder while dissolving a dense surface that appears sequentially from the smooth surface toward the inside. . Therefore, there is a problem that the extraction time becomes long.

  This invention is made | formed in view of such a situation, The place made into the objective is to provide the porous body with a high porosity, and its manufacturing method first. A second object of the present invention is to provide a production method for obtaining a porous material in a short time. The third object of the present invention is to provide a novel functional porous body and a method for producing the same.

  The method for producing a porous body according to the present invention includes the step of decomposing a decomposable foaming agent by heating a molded product of a composition containing a polymer substance, a pore forming agent and a decomposable foaming agent to a temperature at which the polymer substance melts. And a step of extracting a pore-forming agent from the foamed molded product by dissolution in a solvent to form open cells in the molded product.

  According to the production method of the present invention, a porous body having a high porosity can be obtained in a short time by combining foaming and extraction and sequentially performing these.

  The pore forming agent preferably includes a first component having a melting point Mb higher than the melting point Ma of the polymer substance. As a result, the composition containing the polymer substance and pore-forming agent is melted and kneaded with the polymer substance in a state in which the pore-forming agent that does not melt is contained, and the powder-like or particle-like pore-forming agent is contained. It is possible to easily obtain a kneaded product for molding. As a result, open cells can be formed more efficiently.

  The first component of the pore forming agent is preferably a polyhydric alcohol having a melting point Mb of 100 to 350 ° C. The polyhydric alcohol is preferably pentaerythritol.

  When the pore-forming agent contains the first component, the composition contains 100 parts by weight of the polymer material, 50 to 400 parts by weight of the first component of the pore-forming agent, and 1 to 50 parts by weight of the decomposable foaming agent. It is preferable to contain.

  The pore forming agent preferably further includes a second component having a melting point Mc lower than the melting point Ma of the polymer substance. This second component is preferably polyethylene oxide.

  When the pore-forming agent contains the first and second components, the composition comprises 100 parts by weight of a polymer substance, 40 to 450 parts by weight of the first component of the pore-forming agent, and the second component of the pore-forming agent. It is preferable to contain 20-450 weight part and 1-50 weight part of decomposition | disassembly type | mold foaming agents.

  The production method according to the present invention includes a step of melt-kneading the composition at a temperature lower than Ma and a lower temperature than the decomposition temperature Md of Mb and the decomposable foaming agent, and molding the melt-kneaded composition. And obtaining a molded product. In this case, it is preferable to obtain a molded product by molding the composition using an extrusion molding method, a calendar molding method, a press molding method or an injection molding method.

  The polymeric material may be a thermoplastic resin or a thermoplastic elastomer. The polymer substance may be an olefin resin or a polyester resin. The polymer substance may be an ethylene-vinyl acetate copolymer.

  The solvent is preferably water or an aqueous solvent.

  The composition may further contain a functional filler. Thereby, the various functions using an open cell can be provided to a porous body.

  The functional filler is preferably functional polymer particles. This functional polymer particle is preferably a molecular template. This functional polymer is also preferably an ion exchange resin.

  The difference in solubility parameter between the polymer compound constituting the functional polymer particles and the polymer substance constituting the porous body is preferably within one.

  The functional polymer particles preferably have a functional group on the surface. This functional group preferably has reactivity with a polymer substance.

  The porous body according to the present invention contains a polymer substance that forms open cells and has a porosity of 50 to 90% by volume.

  The porous body according to the present invention may further contain the above functional filler. In this case, the functional filler is preferably exposed on the wall surface of the open cell. Since the porous body has a high porosity, the function of the functional filler can be particularly effectively exhibited when the functional filler is exposed on the wall surface of the open cell.

  The functional polymer particles are preferably bonded to the polymer substance by a reaction between the functional group on the surface and the polymer substance.

  The porous body according to the present invention may contain a polymer substance that forms open cells and functional polymer particles that are molecular templates. Moreover, the porous body according to the present invention may contain a polymer substance forming open cells and functional polymer particles that are ion exchange resins.

  The filter medium according to the present invention includes the porous body according to the present invention. The ion exchanger base material according to the present invention includes the porous body according to the present invention.

  According to the production method of the present invention, a porous body having a high porosity can be obtained in a short time. Further, according to the production method of the present invention, the pore-forming agent is removed after foaming, and therefore, a porous body in which open cells are formed and has good water permeability can be easily produced in a short extraction time. Also in the case of producing a porous body having a high porosity, the amount of the pore forming agent used can be reduced, and the pore forming agent can be easily removed. Therefore, production efficiency is good and the obtained porous body can be made more robust.

  The porous body according to the present invention has good air permeability because of its high porosity, and is particularly suitable for filter materials for filtration, ion exchange structural materials, monolithic columns, and the like.

  Further, according to the production method of the present invention, when a functional filler is used, a porous body having various functions using open cells can be easily produced while maintaining good water permeability and the like. Can do.

It is a schematic diagram which shows a water-permeable measuring apparatus. It is a graph which shows the relationship between the extraction time of Example 1, Example 2, and Comparative Example 1 and the porosity of a porous body. It is a graph which shows the relationship between the extraction time of Example 3, Example 4, and Comparative Example 2 and the porosity of a porous body. It is a graph which shows the relationship between the extraction time of Example 5, Example 6, and Comparative Example 3 and the porosity of a porous body. 4 is an electron micrograph (1000 × magnification) of the porous material obtained in Example 7. FIG. 4 is an electron micrograph (1000 × magnification) of the porous body obtained in Example 8. FIG. 4 is an electron micrograph (1000 × magnification) of the porous material obtained in Example 9. 4 is an electron micrograph (lower right: 35 times, lower left: 100 times, upper right; 1000 times, upper left: 2000 times) of the porous body obtained in Example 10. It is an electron micrograph (lower right: 35 times, lower left: 100 times, upper right; 1000 times, upper left: 2000 times) of the porous body obtained in Example 11. It is an electron micrograph (lower right: 35 times, lower left: 100 times, upper right; 1000 times, upper left: 2000 times) of the porous body obtained in Example 12. It is an electron micrograph (lower right: 35 times, lower left: 100 times, upper right; 1000 times, upper left: 2000 times) of the porous body obtained in Example 13. It is an electron micrograph (lower right: 35 times, lower left: 100 times, upper right; 1000 times, upper left: 2000 times) of the porous body obtained in Example 14. It is an electron micrograph of the porous body obtained in Example 15 (lower right: 35 times, lower left: 100 times, upper right; 1000 times, upper left: 2000 times). It is an electron micrograph (lower right: 35 times, lower left: 100 times, upper right; 1000 times, upper left: 2000 times) of the porous body obtained in Example 16. It is a graph which shows the relationship between the extraction time in Example 11 and Comparative Example 4, and the porosity of a porous body. It is a graph which shows the relationship between the extraction time in Example 14 and Comparative Example 5, and the porosity of a porous body.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Porous body, 2 ... Filter holder for filtration, 3 ... Container with pressure reduction pump connection port, 4 ... Clamp, 5 ... Pressure reduction pump connection port

  Hereinafter, preferred embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments.

  The method for producing a porous body according to the present embodiment includes a kneading step of melt-kneading a composition containing a polymer substance, a pore-forming agent and a decomposable foaming agent, and molding a melt-kneaded composition (kneaded material). A molding step to obtain a molded product, a foaming step in which the molded product is heated to a temperature at which the polymer substance melts and foamed by decomposing the decomposable foaming agent, and a pore-forming agent from the foamed molded product is dissolved in a solvent. An extraction step of extracting and forming open cells in the molded product.

  As the polymer substance, a thermoplastic resin, a thermoplastic elastomer or a mixture thereof is preferably used. The melting point Ma of the polymer substance is preferably 100 to 300 ° C.

  As the thermoplastic resin, those suitable for extrusion molding, calendar molding, or injection molding are suitable. Therefore, the thermoplastic resin preferably has a melting point of 100 to 300 ° C. Preferable specific examples of the thermoplastic resin include olefin resins such as polyethylene, polypropylene, ethylene-vinyl acetate copolymer and saponified ethylene-vinyl acetate copolymer, polyester systems such as polyethylene terephthalate and polybutylene terephthalate. Examples include resins, ethylene-methacrylic acid copolymers, polystyrene, AS resins, ABS resins, polyamide 6, polyamide 6,6, polycarbonate, polyacetal, and polyvinyl alcohol. These thermoplastic resins may be used alone or in combination of two or more. Of these, olefin resins and polyester resins are preferred.

  A thermoplastic elastomer is a polymer material composed of a soft segment that imparts rubber-like elasticity and a hard segment that forms a knot of a three-dimensional network, exhibits rubber elasticity at room temperature, and is plasticized at high temperature. Therefore, the thermoplastic elastomer can be easily formed by extrusion molding, calendar molding, or injection molding.

  Specific examples of thermoplastic elastomers include polystyrene elastomers in which the hard segment is polystyrene and the soft segment is polybutadiene, polyisoprene or hydrogenated products thereof, the hard segment is polyethylene or polypropylene, and the soft segment is butyl rubber or EPDM (ethylene-propylene). -Diene copolymer) polyolefin elastomer, hard segment is polyamide and soft segment is polyester or polyether, polyamide elastomer, hard segment is polyester and soft segment is polyether elastomer, and hard segment Is a polyurethane block having a urethane bond and the soft segment is polyester or polyether. Urethane-based elastomers. You may use these by 1 type or in combination of 2 or more types as a polymeric material.

  As the pore forming agent, a material that is soluble in a solvent for extraction and that forms bubbles when extracted by the solvent is used. Therefore, when the polymer substance is melt-kneaded together with the pore-forming agent, the powdery or particulate material can be used to obtain a kneaded product in which the powder-like or particulate pore-forming agent is dispersed in the polymer substance. It is suitably used as a forming agent.

  The pore-forming agent includes a first component (hereinafter, sometimes referred to as “first pore-forming agent”) which is an organic compound having a melting point Mb higher than the melting point Ma of the polymer substance. The first pore forming agent can maintain a solid state at the molding temperature of the composition containing the polymer substance. Therefore, by using the first pore forming agent, it becomes easy to efficiently form open cells after extraction.

  The method for producing a porous body comprises a polymer material having a melting point Ma containing a first pore forming agent having a melting point Mb higher than Ma and a decomposable foaming agent having a thermal decomposition temperature Md higher than Ma. The molded product may be heated to Md or more and foamed, and the first pore-forming agent may be extracted with a solvent that does not dissolve the polymer substance but dissolves the first pore-forming agent.

  It is preferable that melting | fusing point Mb of a 1st pore formation agent is 40-350 degreeC. The lower limit of the melting point Mb is more preferably 100 ° C, still more preferably 150 ° C. The upper limit of the melting point Mb is more preferably 300 ° C. For example, when the melting point Ma of the polymer substance is 100 ° C. to 300 ° C., the melting point Mb of the first pore-forming agent is preferably Ma or more and more than 100 ° C. and 350 ° C. or less, and 150 ° C. to 300 ° C. More preferably, it is ° C.

  As the first pore forming agent, polyhydric alcohol having about 2 to 5 carbon atoms and urea are preferably used. Specific examples of the polyhydric alcohol include pentaerythritol, L-erythritol, D-erythritol, meso-erythritol and binacol. Among these materials, pentaerythritol is particularly preferable. Since pentaerythritol is hydrophilic, water or an aqueous solvent can be selected as a solvent used in the extraction step. Pentaerythritol can be changed depending on its purity, but generally has a melting point of 180 ° C. to 260 ° C., so that it is easy to apply in combination with various polymer substances. Moreover, pentaerythritol has a high rate of solidification from the molten state, so that the cooling time of the molded product can be shortened, which is advantageous for improving productivity.

  Only one type of first pore forming agent may be used, or two or more types may be combined. When two or more types are combined, the formation state of the pores can be more easily changed by combining materials having different particle diameters or materials having different rigidity at the molding temperature.

  It is preferable that the pore forming agent further includes a second component (hereinafter sometimes referred to as “second pore forming agent”) having a melting point Mc lower than the melting point Ma of the polymer substance. It is preferable that melting | fusing point Mc of a 2nd pore formation agent is 50-200 degreeC. Examples of the second pore forming agent include polyethylene oxide and polyethylene glycol. Among these, polyethylene oxide (preferably molecular weight 1 million to 8 million) is desirable from the viewpoint of melt viscosity and the like.

  It is important that the first pore-forming agent and the second pore-forming agent used as necessary are uniformly dispersed in the polymer material in the melt-kneading to obtain a kneaded product for molding. For this reason, you may use a dispersing agent suitably. Examples of the dispersant include higher fatty acids such as stearic acid, higher aliphatic alcohols such as stearyl alcohol, paraffin, and stearamide, palmitylamide, methylene bisstearamide, and ethylene bisstearamide. Higher fatty acid amides.

  A decomposable foaming agent is a component that foams a molded product by decomposing and generating gas when heated to a predetermined decomposition temperature Md or higher. Specific examples of the decomposable foaming agent include azodicarbonamide (ADCA, decomposition temperature 195 to 210 ° C.), azobisisobutyronitrile (AIBN, decomposition temperature 98 to 102 ° C.), barium azodicarboxylate (decomposition temperature 240). ˜250 ° C.), dinitrosopentamethylenetetramine (DPT, decomposition temperature 200-205 ° C.), p, p′-oxybisbenzenesulfonyl hydrazide (OBSH, decomposition temperature 157-162 ° C.), and paratoluenesulfonyl hydrazide (TSH, Decomposition temperature 103-111 ° C.).

  In selecting the decomposable foaming agent, the relationship between the molding temperature of the kneaded material containing the above-described polymer substance and pore forming agent and the decomposing temperature of the decomposable foaming agent is considered. If the melt viscosity of the kneaded product at the decomposition temperature of the decomposable foaming agent is too high, the gas pressure generated by the decomposition of the foaming agent is suppressed by the mechanical strength of the kneaded product, making it difficult for the kneaded product to foam. Conversely, if the melt viscosity of the kneaded product is too low, the generated gas easily breaks through the kneaded product and diverges, making it difficult to foam. From such a viewpoint, for example, when the polymer substance is an olefin resin, azodicarbonamide (ADCA) and dinitrosopentamethylenetetramine (DPT) are particularly suitable as the decomposable foaming agent.

  In order to obtain a better foamed state, the composition may contain a crosslinking agent and / or a crosslinking aid. Examples of the crosslinking agent include dicumyl peroxide, 2,5 dimethyl-2,5-di (t-butylperoxy) hexane, and 2,5 dimethyl-2,5-di (t-butylperoxy) hexyne- An organic peroxide such as 3 can be used. You may use the said crosslinking adjuvant in combination of 2 or more types. The amount of the crosslinking agent is preferably 0 to 5 parts by weight, more preferably 2 parts by weight or less, with respect to 100 parts by weight of the polymer substance. In order to easily develop the effect of the crosslinking agent, the amount of the crosslinking agent is preferably 0.2 parts by weight or more, and more preferably 0.4 parts by weight or more. When the amount of the crosslinking agent is too small, the effect of improving the foamed state tends to be small, and when the amount is too large, it is difficult to improve the degree of foaming.

  Examples of the crosslinking aid include trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, ethylene glycol dimethacrylate, and triallyl isocyanurate. You may use a crosslinking adjuvant in combination of 2 or more types. The amount of the crosslinking aid is preferably 0 to 2 parts by weight, more preferably 1.5 parts by weight or less with respect to 100 parts by weight of the polymer substance. Even if the amount of the crosslinking aid exceeds 2 parts by weight, it is difficult to obtain a significant improvement in foaming improvement effect. In order to easily develop the effect of the crosslinking aid, 0.1 part by weight or more is preferable.

  The composition for obtaining a molded product may further contain a functional filler. The functional filler is an inorganic or organic filler that imparts a specific function to the porous body. As the functional filler, for example, a material that gives a porous body a polishing function, a heat conduction function, a heat conduction prevention function, a conductivity function, a light absorption function, a molecular sieving function, an ion exchange function, or a molecular template function is used. It is done.

  Examples of inorganic functional fillers include abrasives such as silica, aluminum oxide, and cerium oxide, materials that are responsible for heat conduction or prevention of heat conduction such as calcium carbonate and silicon oxide, and heat conductivity or conductivity such as gold, silver, and copper. Metal particles, pigment particles such as titanium oxide.

  Examples of the organic functional filler include functional polymer particles formed of a polymer compound. The functional polymer particles may be ion exchange resin particles, molecular templates, abrasives, or organic pigments. The functional polymer particles may be polystyrene porous particles. The polystyrene porous particle is, for example, a particle used as a column filler for gel permeation chromatography, and may contain a crosslinked structure formed using divinylbenzene. The functional polymer particles may be modifying polymer particles such as polyethylene powder.

  The functional filler may be an inorganic and organic composite material. As an example of the composite material used as the functional filler, there are particles obtained by performing gold plating on polystyrene particles.

  When the functional filler has a melting point or a decomposition point, these temperatures are preferably higher than the lowest temperature among Ma, Mb and Mc described above, and higher than the highest temperature among Ma, Mb and Mc. Higher is more preferable. The melting point or decomposition point of the functional filler is preferably higher than the temperature applied to the functional filler in the manufacturing process of the porous body.

  In order to uniformly disperse the functional polymer particles in the polymer material forming the porous body, the solubility parameter between the polymer compound constituting the functional polymer particles and the polymer material constituting the porous body is The difference is preferably within 1 and more preferably within 0.5.

  The solubility parameter (SP value) is a polymer handbook (Polymer Handbook) pages IV-341 to IV-368 (in collaboration with H.-G.ELIAS, edited by J. BRANDRUP / E.H.IMMERGUT; INTERSCIENCE) This is a value described in “SOLUBILITY PARAMETER VALUE” (by H. Burrell) shown in PUBLISHERS. In addition, “Solvent Handbook” (Shozo Asahara, Jinichiro Tokura, Makoto Okawara, Yasunori Kumano, Manabu Seneo, Kodansha Scientific Co., Ltd., 1976, 1st edition, 1993, 13th edition) 91-93 The page also describes similar solubility parameters. The solubility parameter can be determined by the small method or experimentally.

In the small method, the SP value is δ, and the sum of all F values of atoms and groups in the molecule or repeating unit is ΣF (where F value is molar-attraction constant (unit; (cal · cm ³ ) ^{1 / 2} / mol, 25 ° C.)), where M is the molecular weight (or the molecular weight of the repeating unit), and ρ is the density of the molecule, the SP value δ is given by the formula:

It can ask for.

The F values of main substituents are as follows.
Methyl group (H ₃ C—): 214
Methylene group (—CH ₂ —; secondary carbon): 133
Methylene group (H ₂ C = (double bond)): 190
Methine group (HC; tertiary carbon): 28
Methine group (-HC = (double bond)): 111
Quaternary carbon: 93
Ester group (—COO—): 310
Secondary hydroxyl group (-OH): 300
Phenyl group: 735
Phenylene group: 658

According to the above formula, δ of the ethylene-vinyl acetate copolymer (ethylene: vinyl acetate = 9: 1 (molar ratio), density 0.93) is 8.5 (molecular weight of the repeating unit C ₂₂ H ₄₂ O ₂ : ) Of styrene-divinylbenzene copolymer (styrene: divinylbenzene = 1: 1 (molar ratio), density 0.90) is 7.2 (molecular weight of repeating unit C ₁₈ H ₁₉ : 234.32). ) Of poly (ethylene glycol dimethacrylate) polymer (density 1.1) is 7.7 (molecular weight of repeating unit C ₁₀ H ₁₄ O ₄ : 198.21), poly (glycerol dimethacrylate) (density 1. Δ in 1) is 8.3 (molecular weight of repeating unit C ₁₁ H ₁₆ O ₅ : 228.24).

  When the functional polymer particle is a molecular template, the molecular template can be supported on a polymer material forming a porous body. Such a porous body is convenient to handle when capturing a trace organic compound using a molecular template and collecting the trace organic compound after capture. Since open cells are formed in the porous body, a small amount of a specific organic compound contained in the water can be collected by passing water through the porous body carrying the molecular template. Therefore, the porous body can be used as a kind of filtering agent. For such purposes, it is preferable that the porous body has high water permeability.

  Examples of the functional polymer particles used as the molecular template include polymer particles known as a molecular imprint polymer or a fragment imprint polymer. The imprint polymer selectively adsorbs a target substance under a certain condition and releases the target substance adsorbed under a certain condition.

  These imprint polymers self-associate a template molecule composed of a target substance or a similar compound and a functional monomer by a non-covalent interaction such as hydrogen bonding, and then polymerize in the presence of a crosslinking agent. This is a polymer obtained by performing the method and then removing the template molecule. When bulk polymerization is used, the obtained polymer is appropriately pulverized for use. When suspension polymerization is used, a particulate imprint polymer is obtained, and in this case, pulverization is not always necessary. In order to obtain a particulate imprint polymer, a method known as seed polymerization, particularly a two-stage swelling polymerization method or a multi-stage swelling polymerization method is preferable.

  The target substance is not particularly limited, but a relatively low molecular weight compound is preferable. PCB (perchlorobiphenyl), bisphenol A, brominated bisphenol A, dioxin and the like are environmental hormones and thus attract attention as target substances.

  When bisphenol A is a target substance, not only itself but also para tertiary butylphenol can be used as a template molecule. When brominated bisphenol A is a target substance, not only itself but 2,6-bis- (trifluoromethyl) -benzoic acid can be used as a template molecule.

  As the functional monomer used for obtaining the imprint polymer, a compound having polymerizability (particularly radical polymerizability) is used. The functional monomer has sites (functional groups such as basic groups and acidic groups) that interact with the target substance in addition to the polymerization sites. Specific examples of functional monomers include vinyl pyridine, vinyl imidazole, acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, acrylamide, Examples include methacrylamide, acrylonitrile, methacrylonitrile, glycidyl methacrylate and vinyl acetate.

  As a crosslinking agent used for obtaining an imprint polymer, a radical polymerizable compound having two or more double bonds is preferable. Specific examples thereof include ethylene glycol dimethacrylate, ethylene glycol diacrylate, glycerol dimethacrylate, glycerol diacrylate, tetramethylene glycol dimethacrylate, pentaerythritol tetramethacrylate and divinylbenzene. A radical polymerizable compound having one double bond (hereinafter referred to as “monofunctional monomer”) can be used in combination with a radical polymerizable compound having two or more double bonds. Examples of the monofunctional monomer include alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, octyl methacrylate and 2-ethylhexyl methacrylate, alkyl acrylates such as methyl acrylate, ethyl acrylate, butyl acrylate, octyl acrylate and 2-ethylhexyl acrylate, and There is styrene.

  The above-mentioned two-stage swelling polymerization method or multi-stage swelling polymerization method involves swelling particles of a swellable polymer such as polystyrene with a swelling aid such as dibutyl phthalate, and the swollen particles into a template molecule, a functional monomer, and a crosslink. Suspension in a solvent together with an agent (if necessary together with a monofunctional monomer) and a polymerization initiator, further swelling the particles, and then heating to polymerize the functional polymer together with the crosslinking agent. The polymerization initiator is preferably dissolved in advance in a swelling aid or a crosslinking agent.

  The swelling assistant is preferably one known as a polymer plasticizer as represented by dibutyl phthalate. As the swelling aid, a monofunctional monomer, a crosslinking agent, or a water-insoluble organic solvent may be used.

  As said solvent, water or an aqueous solvent is preferable. As the aqueous solvent, there is a mixed solvent of water and a water-soluble organic solvent. Examples of the water-soluble organic solvent include alcohols such as methanol, ethanol and isobutyl alcohol, ketones such as acetone, methyl ethyl ketone and cyclohexanone, and ethers such as diisopropyl ether and dibutyl ether. In order to well suspend particles and other components, it is preferable to add a polymer dispersant such as polyvinyl alcohol and a surfactant such as an anionic surfactant to the solvent. A porous particulate imprint polymer can be obtained by using a water-insoluble organic solvent such as benzene, toluene, xylene, cyclohexane and hexane together with the above polymer particles and a crosslinking agent. It is preferable that the imprint polymer is porous because many adsorption sites of the target substance are exposed. As the polymerization initiator and the surfactant, those described later can be used.

  As the multistage swelling polymerization method, the polymer particles may be sequentially swelled with a swelling aid, swelled with a water-insoluble organic solvent, and swelled with a crosslinking agent, and then polymerized. In this case, the particles can be suspended in a solvent (water or an aqueous solvent) from any point before polymerization.

  In any of the polymerization methods used for the production of molecular templates as described above, a monofunctional monomer having a functional group is further added and polymerized after the final stage of the polymerization or after the completion of the polymerization, so that the molecular template is surfaced. Can be modified. As the monofunctional monomer having such a functional group, the same functional monomers as those described above can be used. Thereby, the imprint polymer particle which has a functional group on the surface is obtained. This functional group can be used to facilitate adsorption or binding of the imprint polymer to the support. For example, an imprint polymer obtained by using a monofunctional monomer having a carboxyl group as a monofunctional monomer having a functional group was combined with an ethylene-vinyl acetate copolymer as a polymer material forming a porous body. In this case, the imprint polymer can be bonded to the porous body by performing a transesterification reaction between the carboxyl group of the imprint polymer and the acetyl group of the ethylene-vinyl acetate copolymer. Thereby, the imprint polymer can be supported on the porous body.

  Functional fillers (functional polymer particles) such as molecular templates and ion exchange resins are preferably exposed on the wall surfaces of the open cells of the porous body in order to fully exhibit their functions. For this purpose, the difference in solubility parameter between the polymer compound constituting the functional filler and the polymer substance constituting the porous body is preferably within 1 and more preferably within 0.5. Thereby, a functional filler is disperse | distributed uniformly and the exposure to the porous body surface of a functional filler is ensured easily. Alternatively, the functional polymer particles and the polymer substance may be less likely to be mixed by setting the difference in solubility parameter outside these ranges, that is, by making the difference in solubility parameter greater than 0.5 or 1. In this case, if the functional polymer particles are fixed to the wall surface of the porous body by an interaction such as adsorption or chemical bonding, a greater effect can be exhibited by using a smaller amount of the functional polymer particles. Therefore, it is preferable that the surface of the functional polymer particle is modified with a functional group capable of interacting with the polymer substance constituting the porous body. From such a viewpoint, the functional polymer particles preferably have a functional group on the surface thereof that has reactivity with the polymer substance constituting the porous body. Examples of this functional group include a carboxyl group.

  When a molecular template that is functional polymer particles is used as the functional filler, either one of a foaming agent and a pore forming agent may be used, or both may be used. When a foaming agent is not used, a crosslinking agent and a crosslinking aid may not be used.

  The size of the functional polymer particles is arbitrary, but the maximum particle size is preferably 0.1 to 1000 μm. Further, the amount of the functional filler is preferably 0.1 to 300 parts by weight, more preferably 0.5 to 200 parts by weight, with respect to 100 parts by weight of the polymer substance constituting the porous body. preferable.

The suitable compounding ratio of the composition for obtaining a porous body is shown below. In each compounding ratio shown below, the numerical range in parentheses is a more preferable range. In any of the following compositions, it goes without saying that a dispersant may be added to improve kneading workability.
Polymer material 100 parts by weight First pore forming agent 50-400 parts by weight (100-350 parts by weight)
Decomposable foaming agent 1-50 parts by weight (3-20 parts by weight)
0-3 parts by weight of dispersant (0.1-1 parts by weight)
Cross-linking agent 0-5 parts by weight (0.2-2 parts by weight)
Cross-linking aid 0-2 parts by weight (0-1.5 parts by weight)

Moreover, when using a 2nd pore formation agent, the following compounding ratios are preferable.
Polymer material 100 parts by weight First pore forming agent 40 to 450 parts by weight (80 to 300 parts by weight)
Second pore forming agent 20 to 450 parts by weight (40 to 300 parts by weight)
Decomposable foaming agent 1-50 parts by weight (3-20 parts by weight)
0-3 parts by weight of dispersant (0.1-1 parts by weight)
Cross-linking agent 0-5 parts by weight (0.2-2 parts by weight)
Cross-linking aid 0-2 parts by weight (0-1.5 parts by weight)

When a functional filler is used, the following compounding ratio is preferable.
Polymer material 100 parts by weight First pore forming agent 50-400 parts by weight Decomposable foaming agent 1-50 parts by weight (100-350 parts by weight)
Functional filler 0.1-300 parts by weight (0.5-200 parts by weight)
In this case, the following compounding ratio may be used.
Polymer material 100 parts by weight First pore forming agent 50-400 parts by weight (100-350 parts by weight)
Decomposable foaming agent 1-50 parts by weight (3-20 parts by weight)
0-3 parts by weight of dispersant (0.1-1 parts by weight)
Cross-linking agent 0-5 parts by weight (0.2-2 parts by weight)
Cross-linking aid 0-2 parts by weight (0-1.5 parts by weight)
Functional filler 0.1-300 parts by weight (0.5-200 parts by weight)

Furthermore, when using a 2nd pore formation agent, the following compounding ratios are preferable.
Polymer material 100 parts by weight First component of pore forming agent 40 to 450 parts by weight (80 to 300 parts by weight)
Second component of pore forming agent 20 to 450 parts by weight (40 to 300 parts by weight)
Decomposable foaming agent 1-50 parts by weight (3-20 parts by weight)
Functional filler 0.1-300 parts by weight (0.5-200 parts by weight)
In this case, the following compounding ratio may be used.
Polymer material 100 parts by weight First pore forming agent 40-450 parts by weight (80-300 parts by weight)
Second pore forming agent 20 to 450 parts by weight (40 to 300 parts by weight)
Decomposable foaming agent 1-50 parts by weight (3-20 parts by weight)
0-3 parts by weight of dispersant (0.1-1 parts by weight)
Cross-linking agent 0-5 parts by weight (0.2-2 parts by weight)
Cross-linking aid 0-2 parts by weight (0-1.5 parts by weight)
Functional filler 0.1-300 parts by weight (0.5-200 parts by weight)

  When there are too few pore forming agents, the porosity tends to decrease. When there are too many pore forming agents, the porosity becomes too large, and the mechanical strength and moldability tend to be lowered. Further, since the second pore-forming agent plays a role of a modifier that melts during melt-kneading, the first pore-forming agent can be contained more than the second pore-forming agent. If the amount of the foaming agent is too small, the foaming does not substantially occur. If the amount is too large, the appearance may be poor.

  In the composition and a molded product obtained using the same, the total amount of the first pore-forming agent and the second pore-forming agent is preferably 40 to 90% by volume, more preferably 50 to 85% by volume with respect to the entire molded product. % Is preferred. If this total amount is less than 40% by volume, the extraction time tends to be prolonged, and if it exceeds 85% by volume, the mechanical strength and moldability of the resulting porous body tend to be lowered.

The composition may contain a surfactant. Thereby, when extracting a pore formation agent with water or an aqueous solvent, extraction can be performed still more efficiently. As the surfactant, any of an anionic surfactant, a cationic surfactant, and a nonionic surfactant may be used. Examples of the anionic surfactant include alkyl benzene sulfonates such as sodium dodecylbenzene sulfonate, alkyl sulfonates in which SO ₃ Na groups are directly added to alkyl groups, and β-tetrahydronaphthalene in which SO ₃ Na groups are added to naphthalene. Sulfonates and higher fatty acid salts such as sodium oleate are used. Examples of the cationic surfactant include a trialkylbenzylammonium salt and a tetraalkylammonium salt. Nonionic surfactants include polyoxyethylene alkyl ether, polyoxyethylene alkylphenyl ether, polyoxyethylene alkylamine, polyoxyethylene alkylamine fatty acid ester, alkyldiethanolamine, hydroxyalkylmonoethanolamine, and alkydethanolamide. is there. The amount of the surfactant is preferably 0 to 5 parts by weight and more preferably 0.5 to 3 parts by weight with respect to 100 parts by weight of the polymer substance.

  The composition for obtaining the porous body is not limited to the components described above, but for the purpose of increasing the efficiency of the melt-kneading, etc., within the range not departing from the gist of the present invention, the antioxidant and the metal deterioration preventing agent. UV absorbers, antiblocking agents, pigments and the like can be added as necessary.

  In the kneading step, a composition containing the polymer substance, the pore forming agent and the decomposable foaming agent is melt-kneaded while melting the polymer substance. The melt kneading can be performed by a method generally used for melt kneading of a thermoplastic resin or a thermoplastic elastomer. Specifically, melt kneading can be performed using a kneading roll, a Henschel mixer, a single screw extruder, or a twin screw extruder. The kneaded product after kneading is cut into pellets as necessary.

  When the first pore-forming material is used, the composition is melt-kneaded at a temperature lower than the melting point Ma of the polymer substance and lower than the melting point Mb of the first pore-forming agent and the decomposition temperature Md of the decomposable foaming agent. It is preferable to do. As a result, a kneaded product in which the powdery or particulate first pore-forming agent is uniformly dispersed can be easily obtained.

  In the molding step, the kneaded product obtained by melt kneading is shaped into a molded product. In other words, the kneaded product is molded to obtain a molded product. The forming step is performed simultaneously with or after the kneading step. The kneaded product is formed into an arbitrary shape such as a sheet shape, a film shape, a rectangular shape, a cylindrical shape, a columnar shape, and a prismatic shape. The molding method is determined according to the required shape of the molded product. A sheet-like molded product can be obtained by a press molding method, a calendar molding method, or an extrusion molding method. Cylindrical, columnar, and prismatic shaped articles can be obtained by extrusion. In addition, a molded article having an arbitrary three-dimensional shape can be obtained by an injection molding method. A three-dimensional shaped product can also be obtained by once forming the kneaded material into a sheet and then shaping it into a three-dimensional shape by a vacuum forming method, a pressure forming method, or the like.

  In the foaming step, the molded product (solid molded product) obtained from the kneaded product is heated and foamed. The foaming step is performed by raising the temperature of the molded product to the decomposition temperature of the decomposable foaming agent kneaded in the molded product. The temperature rise is performed in a high-temperature tank, for example. When the temperature is raised, the molded product may become soft and stick to the rug. In particular, in the case of a sheet-like molded product, it tends to stick to the rug. Therefore, it is preferable that the molded product is foamed by placing the molded product on a sheet having releasability such as a fluororesin sheet. In the case of a three-dimensionally shaped molded article, it is preferable to support the molded article on an appropriate jig so as not to lose its shape.

  In the extraction step, the pore forming agent is extracted from the foamed molded article using a solvent that dissolves the pore forming agent. The solvent is not particularly limited as long as it is a single solvent or mixed solvent that does not substantially dissolve the polymer substance and dissolves the pore-forming agent, and is appropriately selected depending on the type of polymer substance and pore-forming agent. However, water or an aqueous solvent (aqueous medium) is preferable in consideration of the influence on the environment.

  As the aqueous solvent, a mixed solvent of water and a water-soluble organic solvent is used. Examples of the water-soluble organic solvent include alcohols such as methanol, ethanol and isobutyl alcohol, ketones such as acetone, methyl ethyl ketone and cyclohexanone, and ethers such as diisopropyl ether and dibutyl ether. The ratio of the water-soluble organic solvent is preferably 50% by mass or less in the whole solvent.

  Extraction can be performed by a method of immersing the molded product after the foaming step in water or an aqueous solvent having a liquid temperature of room temperature to 60 ° C. contained in the tank. At this time, if the solvent is stirred with a screw or the like, or if the polymer material is a stretchable material such as an elastomer material, the extraction time is shortened by repeating the drawing process by passing the molded product through two rolls or the like. can do.

  The extraction time varies depending on the thickness of the molded product, the expansion ratio, etc., but is usually selected in the range of 10 to 200 hours. After the extraction, the solvent adhering to the molded product is dried to obtain a porous body in which open cells are formed.

  In the method according to the present embodiment, a porous material having various pore sizes and various porosities by appropriately adjusting the types and amounts of the polymer substance, the pore-forming agent, and the decomposable foaming agent, and the production conditions. You can get a body. In particular, according to this embodiment, a porous body having a high porosity can be easily obtained in a short time.

  In the foaming process, the molded product is foamed. Foaming gives a molded product that is expanded compared to before foaming. For example, in the case of a molded product having a volume of 3 mL obtained by molding a composition having a polymer substance of 40% by volume and a total amount of pore-forming agents of 60% by volume, it is porous only by extraction without undergoing a foaming step. When the body is formed, 60% by volume (1.8 mL) of the pore-forming agent is extracted, and the remaining 40% by volume (1.2 mL) of the polymeric material is formed with a porous body having an apparent volume of 3 mL ( A porosity of 60% by volume) is obtained. On the other hand, when the same 3 mL composition as described above was expanded by the foaming process until the apparent volume became 4 mL, the apparent volume formed by 1.2 mL of the polymer substance after extraction was 4 mL. A porous body having a porosity of 70% by volume is obtained. That is, by passing through the foaming step, a porous material having an apparent volume of 4 mL can be obtained by using the same amount of the polymer material as the composition in which a porous material having an apparent volume of 3 mL can be obtained without the foaming step. .

  As is clear from this, in the present invention, first, by adding a foaming step, a porous body having a high porosity that is difficult to mold from the viewpoint of moldability by a conventional method not including the foaming step is obtained. Secondly, if the extraction amount is reduced, a porous body having the same porosity as that of the conventional method can be produced at a lower cost.

  Thirdly, extracting a solid molded product means that it is extracted from a smooth surface while melting into the inside, and it takes a long time to extract. Since extraction is performed while dissolving the bubbles through the bubbles, there is an advantage that the extraction time can be shortened.

  According to the method according to the present embodiment, a porous body having a porosity of 50 to 90% by volume can be easily produced, and furthermore, a porous body having an unprecedented high porosity of 80 to 90% by volume is obtained. It is also possible to obtain. In addition, the bubbles formed by extraction are open cells, and a porous body having a high porosity and formed with open cells is obtained. Since open cells are formed, a porous body excellent in water permeability can be obtained.

  The porous body obtained by the method according to this embodiment is an open-cell type. Since the porous body is excellent in air permeability and water permeability, it can be suitably used for various filter media, base materials for ion exchangers, and the like. Moreover, since the water content is also excellent, the porous body can be used as a puff material for makeup, a vermicelli material for seals, a hydration material such as ikebana, and the like. Furthermore, the porous body can be suitably used for soundproofing materials, heat insulating materials, shock absorbing materials, vibration damping materials, cushion materials, and the like.

  The cylindrical porous body can be applied as a monolithic column having ion exchange capacity, for example. According to the present invention, it is possible to produce a monolithic column having a high porosity in a short time. Also, for example, if one end of a cylindrical porous body is inserted into the soil of a flower pot and the other end is inserted into the water in the water layer placed beside the flower pot, the water will move through the porous body by capillary action. Thus, water can be supplied to the flower pot. That is, the porous body can be used for water supply.

  The cylindrical porous body includes, for example, a step of arranging a cylindrical molded product of the above-described composition in a tubular container having an inner diameter larger than the diameter of the molded product, and heating the molded product in the tubular container. It can be produced by a method comprising a step of foaming and a step of extracting a pore-forming agent from the foamed molded product. Further, after the foaming step, a step of taking out the foamed molded product from the tubular container, a step of extracting the pore forming agent from the foamed molded product, and a step of accommodating the foamed molded product after extraction in the tubular container; A cylindrical porous body can be obtained by a method comprising As the tubular container, for example, a glass tube, a plastic tube, a steel tube or the like is used.

Example 1
100 parts by weight of an ethylene-vinyl acetate copolymer (manufactured by Mitsui DuPont Polychemical Co., Ltd., trade name: Evaflex P1007, melting point 94 ° C.) is used as the polymer substance, and pentaerythritol (Guangei Chemical Industry Co., Ltd.) is used as the first pore-forming agent. 225 parts by weight, manufactured by Co., Ltd., product name: pentalit, melting point 254 ° C., and 225 parts by weight of polyethylene oxide (manufactured by Sumitomo Seika Co., Ltd., trade name: PEO-18Z, melting point 65 ° C.) as a second pore-forming agent As an agent, 9 parts by weight of azodicarbonamide (manufactured by Otsuka Chemical Co., Ltd., trade name: Uniform AZ, decomposition temperature 199 ° C.) is used, together with a surfactant (trade name: Electro Stripper TS-5, produced by Kao Corporation). Roll part kneading (kneading temperature) 0.8 part by weight and cross-linking agent (Nippon Yushi Co., Ltd., trade name: Park Mill) 150 ℃) was. The kneaded product was heated at 150 ° C. for 5 minutes using a press molding machine (clamping force 50 tons) and then cooled to obtain a sheet-like molded product of 250 mm × 250 mm × thickness 3 mm. Thereafter, the molded product was placed on a fluororesin sheet in a high-temperature tank, and the molded product was foamed by heating at 230 ° C. for 5 minutes.

  The foamed molded product was immersed in water at 40 ° C. in a water tank, and the pore forming agent was extracted while stirring the water with a stirrer during the extraction time shown in the extraction time column of Example 1 in Table 1. After extraction, the molded product was dried in a drying oven at 40 ° C. for 24 hours to obtain a porous body in which open cells were formed.

Example 2
A porous body in which open cells were formed was obtained in the same manner as in Example 1 except that the amount of the foaming agent was changed to 4.5 parts by weight.

Example 3
A porous body in which open cells were formed was obtained in the same manner as in Example 1 except that the amount of the first pore forming agent was changed to 100 parts by weight and the amount of the second pore forming agent was changed to 100 parts by weight.

Example 4
A porous body in which open cells were formed was obtained in the same manner as in Example 3 except that the amount of the foaming agent was changed to 4.5 parts by weight.

Example 5
A porous body in which open cells were formed was obtained in the same manner as in Example 1 except that the thickness of the molded product was changed to 10 mm.

Example 6
A porous body in which open cells were formed was obtained in the same manner as in Example 5 except that the amount of the foaming agent was changed to 4.5 parts by weight.

Comparative Example 1
100 parts by weight of ethylene-vinyl acetate copolymer (Mitsui / DuPont Polychemical Co., Ltd., trade name: Evaflex P1007) as the polymer substance, and pentaerythritol (Guangei Chemical Co., Ltd., product) as the first pore-forming agent Name: Penalit) 225 parts by weight, polyethylene oxide (manufactured by Sumitomo Seika Co., Ltd., trade name: PEO-18Z) 225 parts by weight as the second pore-forming agent, together with a surfactant (product of Kao Corporation) Name: 1 part by weight of electrostripper TS-5) and 0.8 part by weight of a crosslinking agent (trade name: Park Mill, manufactured by NOF Corporation) were roll-kneaded (kneading temperature: 150 ° C.). The kneaded product was heated at 150 ° C. for 5 minutes using a press molding machine (clamping force 50 tons) and then cooled to obtain a molded product of 250 mm × 250 mm × thickness 3 mm.

  Thereafter, the molded product was immersed in water at 40 ° C. in a water tank, and the pore forming agent was extracted while stirring the water with a stirrer during the extraction time shown in Table 1. It was immersed in 40 degreeC water in a tank, and the pore formation agent was extracted, stirring water with a stirrer during the extraction time shown in the extraction time column of Example 1 of Table 1. After extraction, the molded product was dried in a drying furnace at 40 ° C. for 24 hours to obtain a porous body.

Comparative Example 2
A porous body was obtained in the same manner as in Comparative Example 1 except that the amount of the first pore forming agent was changed to 100 parts by weight and the amount of the second pore forming agent was changed to 100 parts by weight.

Comparative Example 3
A porous body was obtained in the same manner as in Comparative Example 1 except that the thickness of the molded product was changed to 10 mm.

Table 1 shows the measurement results of the porosity and water permeability of the porous bodies obtained in Examples and Comparative Examples. The measurement of porosity and water permeability was carried out according to the following procedure for the molded product before extraction and after extraction for a predetermined time.
(1) Porosity (volume%)
Using a Tokyo Science Co., Ltd. air comparison type hydrometer 1000 type, the volume V1 of the porous body in vacuum was measured, and from the volume V calculated from V1 and the vertical, horizontal and height dimensions of the porous body, The porosity was calculated by the formula.
Porosity of porous body = (1− (V1 / V)) × 100 [volume%]
(2) Water permeability FIG. 1 is a schematic view showing a water permeability measuring device. The porous body 1 was sandwiched between a filter holder for filtration (inner diameter 35 mm) 2 manufactured by Toyo Roshi Kaisha Co., Ltd. and a container 3 having a mouth having an inner diameter of 35 mm. The connection port 5 of the container 3 was connected to a vacuum pump, the air in the container was sucked in the direction of arrow A, and the pressure in the container was reduced to 10 cmHg. While continuing depressurization, 50 mL of pure water was supplied to the filter holder 2, and the pure water was moved through the porous body 1 into the container 3. The time (seconds) from when pure water was supplied to when there was no pure water in the filter holder 2 was measured as a water index.

  FIG. 2 is a graph showing the relationship between the porosity and the extraction time of Example 1, Example 2, and Comparative Example 1. From these results, in the porous bodies of Example 1 and Example 2 produced through the foaming process, extraction was possible until the porosity was saturated at the stage where the extraction time was about 15 hours, and the porosity was Has reached 85% by volume or more. On the other hand, in the porous body of Comparative Example 1 obtained without going through the foaming step, it took about 60 to 80 hours to complete the extraction. Furthermore, the porosity of Comparative Example 1 is about 80% by volume, and remains at a low level compared to 85% by volume of Examples 1 and 2.

  Moreover, the porous body of Example 1, 2 produced through the foaming process has a short water passage time, and these porous bodies show very good water permeability. On the other hand, the water passage time of the porous body of Comparative Example 1 produced without going through the foaming step was long, and the water passage was also inferior to Examples 1 and 2.

  FIG. 3 is a graph showing the relationship between the porosity and the extraction time in Example 3, Example 4, and Comparative Example 2. From these results, in the porous bodies of Example 3 and Example 4 produced through the foaming process, extraction was possible until the porosity was saturated at the stage where the extraction time was about 20 hours, and the porosity was Has reached 80% by volume or more. On the other hand, in the porous body of Comparative Example 2 produced without going through the foaming step, the porosity reaches only about 65% by volume even when the extraction time is 90 hours.

  FIG. 4 is a graph showing the relationship between the porosity and the extraction time of Example 5, Example 6, and Comparative Example 3. From these results, in the porous bodies of Example 5 and Example 6 produced through the foaming step, the extraction time was about 40 hours, and the porosity was almost saturated until the porosity was It has reached around 80% by volume. On the other hand, in the porous body of Comparative Example 3 produced without going through the foaming step, it took 90 hours or more to complete the extraction.

  The functional polymer particles of Reference Examples 1 to 4, which are molecular templates using bisphenol A as a target substance, were produced as follows.

Reference Example 1: Production of functional polymer particles (molecular template using polymer compound) (polymerization method: seed polymerization using polystyrene particles)
In a mixture of 6.9 g of polystyrene particles having an average particle size of 1 μm, 4.5 g of swelling aid (dibutyl phthalate), surfactant: 0.7 g of sodium dodecyl sulfate and 40 g of water, ethylene glycol dimethacrylate / 4-vinylpyridine / 63.9 g of a mixture of paratertiary butylphenol / (molar ratio 40/8/1), 3.2 g of a polymerization initiator (2,2′-azobis-2,4-dimethylvaleronitrile), 25.9 g of polyvinyl alcohol, dodecyl A solution in which 2.2 g of sodium sulfate, 47.0 g of toluene, and 320 g of water are uniformly dispersed is added, and stirred at 25 ° C. for 360 minutes to swell polystyrene particles, and then heated to 50 ° C. and polymerized for 240 minutes. went. After 240 minutes, 2.4 g of methacrylic acid was added to surface-modify the particles with methacrylic groups, and polymerization was continued for 600 minutes. Thereafter, the polymer was separated by filtration, and the reaction product was washed with water, methanol, and tetrahydrofuran to remove paratertiary butylphenol. The obtained functional polymer particles (molecular template) had an average particle size of 5 μm. Moreover, the solubility parameter of this molecular template was 9.9 as a result of calculation by the above-mentioned formula.

Reference Example 2: Production of functional polymer particles (styrene-divinylbenzene copolymer particles) Instead of 63.9 g of a mixture of ethylene glycol dimethacrylate / 4-vinylpyridine / paratertiary butylphenol, styrene / divinylbenzene / ( Polymerization was carried out in the same manner as in Reference Example 1 except that 48.6 g of a mixture having a molar ratio of 1/1) was used. No methacrylic acid was added after 240 minutes of polymerization. Others were the same as in Reference Example 1 to produce styrene-divinylbenzene copolymer particles. The average particle diameter of the obtained copolymer particles was 4.5 μm. Further, the solubility parameter of the copolymer particles (molecular template) was 7.2 as a result of calculation by the above formula.

Reference Example 3: Production of functional polymer particles (ethylene glycol dimethacrylate polymer particles) 55.1 g of ethylene glycol dimethacrylate instead of 63.9 g of a mixture of ethylene glycol dimethacrylate / 4-vinylpyridine / paratertiary butylphenol Polymerization was carried out in the same manner as in Reference Example 1 except that was used. No methacrylic acid was added after 240 minutes of polymerization. Others were the same as in Reference Example 1 to produce ethylene glycol dimethacrylate polymer particles. The average particle diameter of the obtained polymer particles was 5 μm. Further, the solubility parameter of the polymer particles (molecular template) was 7.7 as a result of calculation by the above formula.

Reference Example 4: Production of functional polymer particles (glycerol dimethacrylate polymer particles) Instead of 63.9 g of a mixture of ethylene glycol dimethacrylate / 4-vinylpyridine / paratertiary butylphenol, 55.6 g of glycerin dimethacrylate was used. Polymerization was carried out in the same manner as in Reference Example 1 except that. No methacrylic acid was added after 240 minutes of polymerization. Others were the same as in Reference Example 1 to produce glycerol dimethacrylate polymer particles (molecular template). The average particle diameter of the obtained polymer particles was 4.5 μm. The solubility parameter of the polymer particles was 8.3 as a result of calculation by the above formula.

Example 7
100 parts by weight of ethylene-vinyl acetate copolymer (product name: EVAFLEX P1007, density 0.93 g / ml, solubility parameter: 8.5) manufactured by Mitsui DuPont Polychemical Co., Ltd. 225 parts by weight of pentaerythritol (manufactured by Guangei Chemical Co., Ltd., trade name: pentalit) as a forming agent, and 225 parts by weight of polyethylene oxide (manufactured by Sumitomo Seika Co., Ltd., trade name: PEO-18Z) as a second pore forming agent. As a foaming agent, 4.5 parts by weight of azodicarbonamide (manufactured by Otsuka Chemical Co., Ltd., trade name: Uniform AZ) is used together with a surfactant (trade name of Kao Co., Ltd. trade name: Electro Stripper TS-5) 1 Parts by weight, 0.8 parts by weight of a crosslinking agent (trade name: Park Mill manufactured by NOF Corporation) and the above Reference Example 1 Child mold 5 parts by kneading (kneading temperature: 0.99 ° C.) was. The kneaded product was heated at 150 ° C. for 5 minutes using a press molding machine (clamping force 50 tons) and then cooled to obtain a sheet-like molded product of 250 mm × 250 mm × thickness 3 mm. The obtained molded product was placed on a fluororesin sheet in a high-temperature tank and foamed by heating at 230 ° C. for 5 minutes.

  Thereafter, the molded product was immersed in water at 40 ° C. in a water tank, and the pore forming agent was extracted while stirring water with a stirrer for 90 hours. After extraction, the molded product was dried in a drying oven at 40 ° C. for 24 hours to obtain a porous body in which open cells were formed.

Example 8
A porous material was obtained in the same manner as in Example 7 except that the amount of the molecular template was changed to 2 parts by weight.

Example 9
A porous material was obtained in the same manner as in Example 7 except that the amount of the molecular template was changed to 1 part by weight.

Example 10
A porous material was obtained in the same manner as in Example 7 except that the amount of the molecular template was changed to 0 part by weight.

  Using the porous bodies of Examples 7 to 10, adsorption isotherms for bisphenol A were prepared by the following procedure. The adsorption isotherm was created using Freundlich's adsorption isotherm (JIS Z 8830).

  An aqueous solution in which bisphenol A was dissolved in water at a concentration of 0.013 g / L was prepared and used as an adsorption sample. Each porous body (adsorbent) obtained in Examples 7 to 10 was added to 100 mL of the adsorbed sample so as to have different concentrations of 8 to 9 points in the range of 2 wt% to 0.004 wt%. After applying ultrasonic vibration for 5 minutes, stirring was performed for 20 hours. Then, the adsorption amount by the porous body of bisphenol A was measured. The amount of adsorption was determined from the residual concentration of bisphenol A in the adsorption sample. The residual concentration was analyzed based on the liquid chromatography under the following conditions, and was determined based on the area ratio with a separately prepared standard sample. The adsorption isotherm of Freundlich (JIS Z 8830) was determined from the obtained adsorption amount. The results are shown in Table 1.

(Liquid chromatography conditions)
Column: Shimpak VP-ODS (Shimadzu Corporation, 4.6 mm (ID) × 150 mm)
Flow rate: 0.8 mL / min
Temperature: 40 ° C
Detector: UV220nm
Mobile phase: acetonitrile: water = 6: 4

  In the above table, “C” is the residual concentration (g / L) of bisphenol A at equilibrium. From the adsorption isotherm, the adsorption amount (mg) of bisphenol A with respect to 1 g of the adsorbent relative to the residual concentration of bisphenol A in the solution at equilibrium can be found.

  The adsorption amount when the adsorption rate is 50%, that is, when the residual concentration of bisphenol A is 0.0065 g / L (C = 0.655) is calculated as shown in Table 3.

  From the results in Table 3, it is clear that the adsorption performance is increased by introducing the molecular template into the porous body. By setting the amount of the molecular template to 1 part by weight, 2 parts by weight and 5 parts by weight, the adsorption performance is about 2 times, about 3 times and about 9 times that of Example 10 in which no molecular template is used. Expressed.

  The cross sections of the porous bodies of Examples 7 to 9 were observed with electron micrographs (1000 times). 5, 6 and 7 are electron micrographs (magnification 1000 times) showing cross sections of the porous bodies obtained in Examples 7, 8 and 9, respectively. In any porous body, particles of a functional filler (molecular template) adhering to the pore wall surface were observed. More particles of functional filler (molecular template) were observed in the order of Example 7, Example 8, and Example 9. In the case of this example, the difference between the molecular template and the solubility parameter of the polymer material constituting the porous body is 1.4. Carboxyl groups are present on the surface of the molecular template due to surface modification, and it is thought that the molecular template particles are anchored to the surface of the porous material by interacting with the polymer material constituting the porous material. .

  Furthermore, when the cross section of the porous body obtained in the same manner as in Example 7 was observed with an electron microscope, except that the amount of the molecular template obtained in Reference Example 1 was changed to 10 parts by weight or 15 parts by weight, More molecular template particles could be observed on the surface of the porous body in the order of 1 part by weight, 2 parts by weight, 5 parts by weight, 10 parts by weight and 15 parts by weight of the molecular template.

  8 is an electron micrograph (35 times, 100 times, 1000 times, 2000 times) showing a cross section of the porous body obtained in Example 10. FIG. Of course, no functional filler particles are observed.

Example 11
As a polymer substance, 100 parts by weight of ethylene-vinyl acetate copolymer (EVA, manufactured by Mitsui DuPont Polychemical Co., Ltd., trade name: EVAFLEX P1007, density 0.93 g / ml, solubility parameter 8.5) 225 parts by weight of pentaerythritol (manufactured by Guangei Chemical Co., Ltd., trade name: pentalit) as a pore forming agent, and 225 weights of polyethylene oxide (trade name: PEO-18Z, manufactured by Sumitomo Seika Co., Ltd.) as a second pore former. Parts are 4.5 parts by weight of azodicarbonamide (manufactured by Otsuka Chemical Co., Ltd., trade name: Uniform AZ) as a foaming agent, together with a surfactant (trade name of Kao Co., Ltd. trade name: Electro Stripper TS-5). 1 part by weight, obtained by 0.8 parts by weight of crosslinking agent (trade name: Park Mill, manufactured by NOF Corporation) and Reference Example 4 Glycerol dimethacrylate polymer particles 5 parts by weight of kneading (kneading temperature: 0.99 ° C.) was. The kneaded product was heated at 150 ° C. for 5 minutes using a press molding machine (clamping force 50 tons) and then cooled to obtain a molded product of 250 mm × 250 mm × thickness 3 mm. The obtained molded product was placed on a fluororesin sheet in a high-temperature tank and foamed by heating at 230 ° C. for 5 minutes.

  Thereafter, the molded product was immersed in water at 40 ° C. in a water tank, and during the extraction time (5-90 hours) shown in the extraction time column of Example 4 in Table 3, the pore forming agent was stirred with water with a stirrer. Extracted. After extraction, the molded product was dried in a drying oven at 40 ° C. for 24 hours to obtain a porous body in which open cells were formed.

Example 12
As a polymer substance, 100 parts by weight of ethylene-vinyl acetate copolymer (EVA, manufactured by Mitsui DuPont Polychemical Co., Ltd., trade name: EVAFLEX P1007, density 0.93 g / ml, solubility parameter 8.5) 225 parts by weight of pentaerythritol (manufactured by Guangei Chemical Co., Ltd., trade name: pentalit) as a pore forming agent, and 225 weights of polyethylene oxide (trade name: PEO-18Z, manufactured by Sumitomo Seika Co., Ltd.) as a second pore former. Parts are 4.5 parts by weight of azodicarbonamide (manufactured by Otsuka Chemical Co., Ltd., trade name: Uniform AZ) as a foaming agent, together with a surfactant (trade name of Kao Co., Ltd. trade name: Electro Stripper TS-5). Obtained by 1 part by weight, 0.8 part by weight of a crosslinking agent (Nippon Yushi Co., Ltd., trade name: Park Mill) and Reference Example 3 above Ethylene glycol dimethacrylate polymer particles 5 parts by weight were kneading (kneading temperature: 0.99 ° C.) it was. The kneaded product was heated at 150 ° C. for 5 minutes using a press molding machine (clamping force 50 tons) and then cooled to obtain a molded product of 250 mm × 250 mm × thickness 3 mm. The obtained molded product was placed on a fluororesin sheet in a high-temperature tank and foamed by heating at 230 ° C. for 5 minutes.

  Thereafter, the molded product was immersed in water at 40 ° C. in a water tank, and the pore forming agent was extracted while stirring water with a stirrer for 90 hours. After extraction, the molded product was dried in a drying oven at 40 ° C. for 24 hours to obtain a porous body in which open cells were formed.

Example 13
As a polymer substance, 100 parts by weight of ethylene-vinyl acetate copolymer (EVA, manufactured by Mitsui DuPont Polychemical Co., Ltd., trade name: EVAFLEX P1007, density 0.93 g / ml, solubility parameter 8.5) 225 parts by weight of pentaerythritol (manufactured by Guangei Chemical Co., Ltd., trade name: pentalit) as a pore forming agent, and 225 weights of polyethylene oxide (trade name: PEO-18Z, manufactured by Sumitomo Seika Co., Ltd.) as a second pore former. Parts are 4.5 parts by weight of azodicarbonamide (manufactured by Otsuka Chemical Co., Ltd., trade name: Uniform AZ) as a foaming agent, together with a surfactant (trade name of Kao Co., Ltd. trade name: Electro Stripper TS-5). Obtained by 1 part by weight, 0.8 part by weight of a crosslinking agent (Nippon Yushi Co., Ltd., trade name: Park Mill) and Reference Example 2 above Styrene - divinylbenzene copolymer particles 5 parts by weight of kneading (kneading temperature: 0.99 ° C.) was. The kneaded product was heated at 150 ° C. for 5 minutes using a press molding machine (clamping force 50 tons) and then cooled to obtain a molded product of 250 mm × 250 mm × thickness 3 mm. The obtained molded product was placed on a fluororesin sheet in a high-temperature tank and foamed by heating at 230 ° C. for 5 minutes.

  Thereafter, the molded product was immersed in water at 40 ° C. in a water tank, and the pore forming agent was extracted while stirring water with a stirrer for 90 hours. After extraction, the molded product was dried in a drying oven at 40 ° C. for 24 hours to obtain a porous body in which open cells were formed.

  9, 10 and 11 are electron micrographs of a cross section of the porous body containing the functional filler obtained in Examples 11-13. In each figure, the lower right is 35 times, the lower left is 100 times, the upper right is 1000 times, and the upper left is 2000 times. Glycerol dimethacrylate polymer particles whose solubility parameter best approximates the polymer material constituting the porous material are ethylene glycol dimethacrylate polymer particles and styrene having a larger difference in solubility parameter from the polymer material constituting the porous material. -More observed on the pore wall surface of the porous body than the divinylbenzene copolymer particles.

Example 14
As a polymer substance, 100 parts by weight of polyethylene resin (manufactured by Asahi Kasei Chemicals Corporation, trade name: Suntech LD F2225, solubility parameter 8.1 experimentally determined from solvent solubility, melting point 112 ° C.) is used as a first pore-forming agent. 225 parts by weight of pentaerythritol (manufactured by Guangei Chemical Co., Ltd., trade name: pentalit), and 225 parts by weight of polyethylene oxide (trade name: PEO-18Z, manufactured by Sumitomo Seika Co., Ltd.) as the second pore-forming agent As an agent, 4.5 parts by weight of azodicarbonamide (manufactured by Otsuka Chemical Co., Ltd., trade name: Uniform AZ) is used, together with 1 part by weight of a surfactant (trade name: Electro Stripper TS-5, produced by Kao Corporation), 0.8 part by weight of a cross-linking agent (Nippon Yushi Co., Ltd., trade name: Park Mill) and the grease obtained in Reference Example 4 above 5 parts by weight of serol dimethacrylate polymer particles were roll kneaded (kneading temperature: 150 ° C.). The kneaded product was heated at 150 ° C. for 5 minutes using a press molding machine (clamping force 50 tons) and then cooled to obtain a molded product of 250 mm × 250 mm × thickness 3 mm. The obtained molded product was placed on a fluororesin sheet in a high-temperature tank and foamed by heating at 230 ° C. for 5 minutes.

  Thereafter, the molded product was immersed in water at 40 ° C. in a water tank, and during the extraction time (5-90 hours) shown in the extraction time column of Example 4 in Table 4, the pore forming agent was stirred with water with a stirrer. Extracted. After extraction, the molded product was dried in a drying oven at 40 ° C. for 24 hours to obtain a porous body in which open cells were formed.

Example 15
As a polymer substance, polyethylene resin (PE, manufactured by Asahi Kasei Chemicals Corporation, trade name: Suntech LD F2225) 100 parts by weight, and as a first pore-forming agent, pentaerythritol (produced by Guangei Chemical Industry Co., Ltd., trade name: Pentalit) 225 225 parts by weight of polyethylene oxide (manufactured by Sumitomo Seika Co., Ltd., trade name: PEO-18Z) as a second pore-forming agent, and azodicarbonamide (manufactured by Otsuka Chemical Co., Ltd., trade name: Uniform AZ) as a foaming agent ) 4.5 parts by weight, together with these, 1 part by weight of a surfactant (trade name: Electro Stripper TS-5, manufactured by Kao Corporation), 0.8 part by weight of a crosslinking agent (trade name: Park Mill, manufactured by NOF Corporation) Parts and 5 parts by weight of ethylene glycol dimethacrylate polymer particles obtained in Reference Example 3 above are roll kneaded. (Kneading temperature: 150 ° C.). The kneaded product was heated at 150 ° C. for 5 minutes using a press molding machine (clamping force 50 tons) and then cooled to obtain a molded product of 250 mm × 250 mm × thickness 3 mm. The obtained molded product was placed on a fluororesin sheet in a high-temperature tank and foamed by heating at 230 ° C. for 5 minutes.

  Thereafter, the molded product was immersed in water at 40 ° C. in a water tank, and the pore forming agent was extracted while stirring water with a stirrer for 90 hours. After extraction, the molded product was dried in a drying oven at 40 ° C. for 24 hours to obtain a porous body in which open cells were formed.

Example 16
As a polymer substance, polyethylene resin (PE, manufactured by Asahi Kasei Chemicals Corporation, trade name: Suntech LD F2225) 100 parts by weight, and as a first pore-forming agent, pentaerythritol (produced by Guangei Chemical Industry Co., Ltd., trade name: Pentalit) 225 225 parts by weight of polyethylene oxide (manufactured by Sumitomo Seika Co., Ltd., trade name: PEO-18Z) as a second pore-forming agent, and azodicarbonamide (manufactured by Otsuka Chemical Co., Ltd., trade name: Uniform AZ) as a foaming agent ) 4.5 parts by weight, together with these, 1 part by weight of a surfactant (trade name: Electro Stripper TS-5, manufactured by Kao Corporation), 0.8 part by weight of a crosslinking agent (trade name: Park Mill, manufactured by NOF Corporation) Part and 5 parts by weight of the styrene-divinylbenzene copolymer particles obtained in Reference Example 2 were kneaded in a roll (kneaded). Temperature: 150 ° C.). Then, after heating for 5 minutes at 150 degreeC using the press molding machine (clamping force 50 tons), it cooled and obtained the molding of 250 mm x 250 mm x thickness 3mm. The obtained molded product was placed on a fluororesin sheet in a high-temperature tank and foamed by heating at 230 ° C. for 5 minutes.

  Thereafter, the molded product was immersed in water at 40 ° C. in a water tank, and the pore forming agent was extracted while stirring water with a stirrer for 90 hours. After extraction, the molded product was dried in a drying oven at 40 ° C. for 24 hours to obtain a porous body in which open cells were formed.

  12, 13 and 14 are electron micrographs showing cross sections of the porous bodies with functional fillers obtained in Examples 14-16. In each figure, the lower right is 35 times, the lower left is 100 times, the upper right is 1000 times, and the upper left is 2000 times. As in Examples 11 to 13, the glycerol dimethacrylate polymer particles having the solubility parameter most closely approximated to the polymer material constituting the porous body have a larger difference in solubility parameter from the polymer material constituting the porous body. Compared with ethylene glycol dimethacrylate polymer particles and styrene-divinylbenzene copolymer particles, more were observed on the pore wall surface of the porous body.

Comparative Example 4
As a polymer substance, 100 parts by weight of an ethylene-vinyl acetate copolymer (EVA, manufactured by Mitsui DuPont Polychemical Co., Ltd., trade name: Everflex P1007) and pentaerythritol (Guangei Chemical Industry Co., Ltd.) as a first pore-forming agent , Manufactured product name: Penalit), 225 parts by weight of polyethylene oxide (manufactured by Sumitomo Seika Chemicals Co., Ltd., product name: PEO-18Z) as a second pore forming agent, and a surfactant (Kao Co., Ltd.). 1 part by weight of company-made trade name: Electro Stripper TS-5) and 0.8 part by weight of a crosslinking agent (trade name: Park Mill, manufactured by NOF Corporation) were roll-kneaded (kneading temperature: 150 ° C.). The kneaded product was heated at 150 ° C. for 5 minutes using a press molding machine (clamping force 50 tons) and then cooled to obtain a molded product of 250 mm × 250 mm × thickness 3 mm.

  Thereafter, the molded product was immersed in water at 40 ° C. in a water tank, and during the extraction time (5-90 hours) shown in the extraction time column of Comparative Example 2 in Table 4, the pore forming agent was stirred with water with a stirrer. Extracted. After extraction, the molded product was dried in a drying oven at 40 ° C. for 24 hours to obtain a porous body in which open cells were formed.

Comparative Example 5
A porous material was obtained in the same manner as in Comparative Example 4, except that polyethylene resin (PE, trade name: Suntec LD F2225, manufactured by Asahi Kasei Chemicals Corporation) was used as the polymer substance.

  The porosity and water permeability of the porous bodies obtained in Examples 7 to 16 and Comparative Examples 4 and 5 were measured by the methods described above. The measurement results are shown in Table 4 together with the blending ratio and the like.

  FIG. 15 is a graph showing the relationship between porosity and extraction time in Example 11 and Comparative Example 4. In the porous body of Example 11 produced through the foaming step, extraction was possible until the porosity was saturated at a stage where the extraction time was about 15 hours, and the porosity was 5 parts by mass for the functional filler. Despite being filled, it reaches 80% by volume or more. On the other hand, in the porous body of Comparative Example 4 produced without passing through the foaming step, it can be seen that a long time of 40 to 60 hours is required until the extraction rate is saturated. Further, the porosity of Comparative Example 4 reached only about 80% by volume although the functional filler was not filled.

  Moreover, the porous body of Example 11 produced through the foaming process has a short water passage time, and the water passage is very good. On the other hand, the porous body of Comparative Example 4 produced without going through the foaming step had a long water passage time and was poor in water passage.

  FIG. 16 is a graph showing the relationship between porosity and extraction time in Example 14 and Comparative Example 5. In the porous body of Example 14 produced through the foaming process, extraction was possible until the porosity was saturated at the stage where the extraction time was approximately 20 hours, and the porosity was filled with 5 parts by weight of the functional filler. Despite being done, it reaches 80% by volume or more. On the other hand, in the porous body of Comparative Example 5 produced without going through the foaming step, it can be seen that a long time of 60 to 80 hours is required until the extraction rate is saturated. Further, the porosity of Comparative Example 5 was about 77% by volume even though the functional filler was not filled, and was lower than that of Example 14.

  Moreover, the porous body of Example 14 produced through the foaming process has a short water passage time, and the water passage is very good. On the other hand, the porous body of Comparative Example 4 produced without going through the foaming step had a long water passage time and was poor in water passage.

  From the above, it can be seen that when the molded product is foamed before the extraction step using a foaming agent, the porosity is higher than when there is no foaming step. This is considered to be because the molded product becomes bulky due to the foaming process, and the porosity increases accordingly. That is, it can be seen that a foam having a high porosity can be obtained in a short extraction time by using a smaller amount of material by foaming the molded product before the extraction step using a foaming agent. This makes it possible to reduce processing costs. Furthermore, as is apparent from the results of the water permeability test, the obtained porous body is found to be a porous body in which open cells having good water permeability are formed.

Example 17
As a high molecular weight substance, 100 parts by weight of ethylene-vinyl acetate copolymer (Mitsui / DuPont Polychemical Co., Ltd., trade name: EVAFLEX P1007, density 0.93 g / mL, solubility parameter 8.5) is used as the first pore. 225 parts by weight of pentaerythritol (manufactured by Guangei Chemical Co., Ltd., trade name: pentalit) as a forming agent, and 225 parts by weight of polyethylene oxide (manufactured by Sumitomo Seika Co., Ltd., trade name: PEO-18Z) as a second pore forming agent. In addition, 4.5 parts by weight of azodicarbonamide (manufactured by Otsuka Chemical Co., Ltd., trade name: Uniform AZ) is used as a foaming agent, together with 1 part by weight of a surfactant (trade name of Kao Corporation, trade name: Electro Stripper TS-5). Part, 0.8 part by weight of a crosslinking agent (dicumyl peroxide) and a commercially available gel type strongly acidic cation exchange resin (crosslinking) Sodium polystyrene sulfonate type cation exchange resin, particle size range 200-240 μm (85% or more), apparent density: 805 g / L, moisture: 52-55.5%, 100 parts by weight of roll kneading (kneading temperature: 150 ° C. )did.

  The obtained kneaded product was extruded using a twin screw extruder (screw diameter: 20 mm) at a cylinder temperature of 150 ° C. to obtain a cylindrical molded product having a diameter of 3 mm. This cylindrical molded product was cut into a length of 10 cm and inserted into a glass tube having an inner diameter of 3.5 mm and an outer diameter of 4.5 mm. The cylindrical molded product inserted into the glass tube was placed in a thermostatic bath and foamed by heating at 230 ° C. for 5 minutes. After foaming, the glass tube was broken and a cylindrical foamed molded product was taken out.

  Thereafter, the molded product was immersed in water at 40 ° C. in a water tank, and the pore forming agent was extracted while stirring water with a stirrer for 90 hours. After extraction, the molded product was dried in a drying oven at 40 ° C. for 24 hours to obtain a porous body in which open cells were formed.

Example 18
The kneaded material obtained in the same manner as in Example 17 was heated and pressurized at 150 ° C. for 5 minutes using a press molding machine (clamping force 50 tons), then cooled, and 250 mm × 250 mm × thickness 3 mm. A sheet-like molded product was obtained. The obtained molded product was placed on a fluororesin sheet in a high-temperature tank and foamed by heating at 230 ° C. for 5 minutes.

  Thereafter, the molded product was immersed in water at 40 ° C. in a water tank, and the pore forming agent was extracted while stirring water with a stirrer for 90 hours. After extraction, the molded product was dried in a drying oven at 40 ° C. for 24 hours to obtain a sheet-like porous body in which open cells were formed.

  The porosity and ion exchange capacity of the porous bodies obtained in Examples 17 and 18 were measured. In Example 18, water permeability was also measured. The ion exchange capacity was measured by the following procedure. Tables 5 and 6 show the composition ratio of the composition and the evaluation results of the porous body.

Method for Measuring Ion Exchange Capacity About 0.5 g of sample was placed in a 100 mL beaker and subjected to ultrasonic treatment for 10 minutes each using methanol and ultrapure water. Thereafter, the sample was drained lightly, the sample was immersed in 20 mL of a 1.5 M hydrochloric acid aqueous solution, and ultrasonic waves were applied for 3 hours while gently pressing the surface with a stir bar to remove air. Then, the sample was taken out, the sample was immersed in 20 mL of new 1.5M-hydrochloric acid aqueous solution, and ultrasonic waves were further applied for 3 hours as before. Then, after thoroughly washing with ultrapure water, the water was thoroughly drained and the sample was transferred to a petri dish and vacuum dried overnight. The dried sample was transferred to a 100 mL Erlenmeyer flask, 20 mL of 1M sodium chloride aqueous solution was added thereto, and the sample was immersed in the 1M sodium chloride aqueous solution for 6 hours while being covered with a film and applying ultrasonic waves. Subsequently, 0.1 mL of phenolphthalein was added as an indicator, and titration was performed using a 0.1 M aqueous sodium hydroxide solution. The factor value was calculated | required about the 0.1M-sodium hydroxide aqueous solution using 0.01M-hydrochloric acid aqueous solution, and the measured value was correct | amended. The ion exchange capacity Q was calculated by the following formula.
Ion exchange capacity Q [meq. / G] = xyf / m
x: Concentration of sodium hydroxide solution [N]
y: titration [mL]
m: Sample mass (dry mass) [g]
f: Factor value of sodium hydroxide solution

  As shown in the above table, a columnar or sheet-like porous body having high ion exchange ability was obtained by using an ion exchange resin as a functional filler. A cylindrical porous body can be effectively applied as a monolithic column.

Claims (34)

Heating a molded product of a composition containing a polymer substance, a pore-forming agent and a decomposable foaming agent to a temperature at which the polymer substance melts, and foaming by decomposing the decomposable foaming agent;
Extracting the pore-forming agent from the foamed molded product by dissolution in a solvent to form open cells in the molded product;
A method for producing a porous body comprising:   The manufacturing method of Claim 1 with which the said pore formation agent contains the 1st component which has melting | fusing point Mb higher than melting | fusing point Ma of the said high molecular substance.   The manufacturing method of Claim 2 whose said 1st component is a polyhydric alcohol which has 100-350 degreeC melting | fusing point Mb.   The production method according to claim 3, wherein the polyhydric alcohol is pentaerythritol. The composition is
100 parts by weight of the polymer substance,
The production method according to claim 2, comprising 50 to 400 parts by weight of the first component of the pore-forming agent and 1 to 50 parts by weight of the decomposable foaming agent.   The manufacturing method of Claim 2 with which the said pore formation agent further contains the 2nd component which has melting | fusing point Mc lower than melting | fusing point Ma of the said high molecular substance.   The production method according to claim 6, wherein the second component is polyethylene oxide. The composition is
100 parts by weight of the polymer substance,
40 to 450 parts by weight of the first component of the pore forming agent,
The manufacturing method of Claim 6 containing 20-450 weight part of 2nd components of the said pore formation agent, and 1-50 weight part of said decomposable foaming agents. A step of melting and kneading the composition at a temperature lower than Ma and a lower temperature than Mb and a decomposition temperature Md of the decomposition-type foaming agent;
Forming the melt-kneaded composition to obtain the molded product;
The manufacturing method according to claim 2, further comprising:   The manufacturing method of Claim 9 which shape | molds the said composition using an extrusion molding method, a calendar molding method, a press molding method, or an injection molding method, and obtains the said molded object.   The production method according to claim 1, wherein the polymer substance is a thermoplastic resin or a thermoplastic elastomer.   The manufacturing method according to claim 1, wherein the polymer substance is an olefin resin or a polyester resin.   The production method according to claim 1, wherein the polymer substance is an ethylene-vinyl acetate copolymer.   The production method according to claim 1, wherein the solvent is water or an aqueous solvent.   The manufacturing method according to claim 1, wherein the composition further contains a functional filler.   The manufacturing method according to claim 15, wherein the functional filler is functional polymer particles.   The production method according to claim 16, wherein the functional polymer particle is a molecular template.   The production method according to claim 16, wherein the functional polymer particles are an ion exchange resin.   The manufacturing method according to claim 20, wherein a difference in solubility parameter between the polymer compound constituting the functional polymer particles and the polymer substance is within one.   The manufacturing method of Claim 16 with which the said functional polymer particle has a functional group on the surface.   The manufacturing method according to claim 20, wherein the functional group has reactivity with the polymer substance.   A porous body containing a polymer substance forming open cells and having a porosity of 50 to 90% by volume.   The porous body according to claim 22, further comprising a functional filler.   The porous body according to claim 23, wherein the functional filler is exposed on a wall surface of the open cell.   The porous body according to claim 23, wherein the functional filler is functional polymer particles.   The porous body according to claim 25, wherein the functional polymer particle is a molecular template.   The porous body according to claim 25, wherein the functional polymer particles are an ion exchange resin.   The porous body according to claim 25, wherein a difference in solubility parameter between the polymer compound constituting the functional polymer particles and the polymer substance is within one.   The porous body according to claim 25, wherein the functional polymer particles are bonded to the polymer substance by a reaction between a functional group on the surface thereof and the polymer substance.   A porous body containing a polymer substance forming open cells and functional polymer particles as a molecular template.   The porous body according to claim 30, wherein a difference in solubility parameter between the polymer compound constituting the functional polymer particles and the polymer substance is 1 or less.   The porous body according to claim 30, wherein the functional polymer particle is bonded to the polymer substance by a reaction between a functional group on the surface thereof and the polymer substance.   A filter medium comprising the porous body according to any one of claims 22 to 32.   An ion exchanger base material comprising the porous body according to any one of claims 22 to 32.