JP4362074B2 - Aldehydes, acid gas and basic gas removal materials - Google Patents

Description

  The present invention relates to a material for removing aldehydes, acidic gas, and basic gas.

  In recent years, sick house syndrome caused by harmful chemical substances such as formaldehyde released indoors from building materials and wall materials used when renovating new houses and houses has become a problem, and technology to remove these harmful chemical substances Is urgently needed.

  So far, various deodorant fiber materials have been developed for the purpose of removing bad odors caused by lower aldehydes caused by tobacco smoking and offensive odors such as ammonia, amines, hydrogen sulfide, mercaptans, etc. It has been.

For example, a deodorizing polymer obtained by combining polyalkyleneimine (NH ₂ (CR ₂ CR ₂ NH) _n H (R is hydrogen or an alkyl group)) with an organic polymer substrate having an acidic group such as a carboxyl group. However, it has been reported that it has an excellent deodorizing performance against acetaldehyde, sulfurous acid gas and nitrous acid gas (see Patent Document 1).

However, the deodorizing polymer described in Patent Document 1 does not have basic gas adsorption performance.
Further, when the deodorizing fiber containing a fiber metal salt in which a transition metal ion is bonded to a carboxyl group has a deodorizing performance with respect to a compound having a carbonyl group such as tobacco odor, hydrogen sulfide, ammonia, trimethylamine and the like. Have been reported (see Patent Documents 2 and 3).

  However, the deodorant fiber described in Patent Document 2 uses an acrylic synthetic fiber obtained by a wet spinning method, and the deodorant fiber material described in Patent Document 3 uses a synthetic resin binder, so that the material is limited. Will be.

JP-A-3-218766 JP-A-8-74131 Japanese Patent Laid-Open No. 10-292263

  Therefore, the present invention has an object of providing a material with less restrictions on the material and efficiently adsorbing and removing aldehydes, acidic gas, and basic gas, and a method for producing the material.

  As a result of diligent research, the present inventors have found that organic compounds are obtained by using graft monomers that have fewer restrictions on materials and that can control the addition amount of sulfonic acid groups and that can be easily converted into sulfonic acid groups. A sulfonic acid group can be introduced not only into the surface of the polymer substrate but also into the inside thereof, and a primary amine group is produced by reacting a polyamine compound with the sulfonic acid group introduced into the surface of the organic polymer substrate. One or more basic functional groups selected from the group consisting of a secondary amino group, a tertiary amino group and a quaternary ammonium group can be fixed, and these basic groups not bonded to a sulfonic acid group Knowing that a polyamine layer having a functional group and a primary amino group can be formed on the surface of the organic polymer substrate, a primary amino group mainly serving as an adsorption site for aldehydes, To obtain a material capable of efficiently adsorbing and removing aldehydes, acidic gas and basic gas, having free basic functional groups serving as acid gas adsorption sites, mainly sulfonic acid groups serving as basic gas adsorption sites Succeeded.

  That is, according to the present invention, a core layer including an organic polymer substrate having a sulfonic acid group introduced by a graft polymerization method, a sulfonic acid group, a primary amino group, and a secondary layer on the surface of the core layer. It is immobilized on the surface of the core layer by bonding with one or more basic functional groups selected from the group consisting of an amino group, a tertiary amino group, and a quaternary ammonium group. A polyamine having one or more basic functional groups selected from the group consisting of a primary amino group, a secondary amino group, a tertiary amino group, and a quaternary ammonium group for bonding, and a primary amino group Aldehydes, acid gases and basic gas removal materials comprising a two-layer structure are provided.

  In the present invention, the core layer includes an organic polymer base material having a sulfonic acid group introduced not only to the surface of the organic polymer base material but also to the inside of the organic polymer base material by a graft polymerization method. Configure the adsorption site. Organic polymer base materials introduced with sulfonic acid groups by the graft polymerization method have a high degree of freedom for the flow and contact of gases and low-molecular substances, since the graft polymerization part into which sulfonic acid groups are introduced does not have a crosslinked structure. Therefore, the contact efficiency and contact area with the basic gas to be adsorbed and removed are high, and the basic gas can be adsorbed and removed efficiently. The polyamine layer is mainly composed of at least one basic functional group selected from a free primary amino group, secondary amino group, tertiary amino group, and quaternary ammonium group constituting an acidic gas adsorption site. Group and a primary amino group mainly constituting an aldehyde adsorption site. Furthermore, the polyamine layer is at least one base selected from a primary amino group, a secondary amino group, a tertiary amino group, and a quaternary ammonium group bonded to a sulfonic acid group on the surface of the core layer. As shown in FIG. 1, a two-layer structure in which a polyamine layer 2 is fixed on the surface of the core layer 1 is formed.

  As a graft polymerization method used in the present invention, a peroxide such as benzoyl peroxide is used as a radical initiator, and graft polymerization is started by heating, oxidation, or reduction. It may be a radiation graft polymerization method in which a radical is generated by irradiating radiation to initiate graft polymerization. In addition, the liquid phase graft polymerization method in which the polymerization is performed with the graft substrate immersed in the monomer solution by the contact method between the monomer and the graft substrate, and the polymerization is performed by bringing the graft substrate into contact with the vapor of the monomer. Examples of the gas phase graft polymerization method include an impregnation gas phase graft polymerization method in which a graft base material is immersed in a monomer solution and then taken out from the monomer solution to perform a reaction in the gas phase. Can be used.

  In the present invention, the number and length of the graft chains can be controlled relatively freely, the polymer side chains can be introduced into the existing polymer materials of various shapes, Radiation graft polymerization is particularly preferred because it allows effective graft polymerization and can form side chains capable of introducing sulfonic acid groups up to the inside of the graft substrate. Examples of radiation that can be used in the radiation graft polymerization method include α-rays, β-rays, γ-rays, electron beams, and ultraviolet rays, and γ-rays and electron beams are particularly suitable for use in the present invention. Yes.

  The radiation graft polymerization method includes a pre-irradiation graft polymerization method in which a graft substrate is irradiated with radiation in advance and then brought into contact with a polymerizable monomer (graft monomer) to react, and the graft substrate and monomer coexist. There are simultaneous irradiation graft polymerization methods in which radiation is irradiated, and any method can be used in the present invention. However, the pre-irradiation graft polymerization method is particularly preferable because side reactions other than graft polymerization hardly occur. When the pre-irradiation graft polymerization method is used, the reaction is preferably performed at a temperature of 20 to 80 ° C., preferably 30 to 50 ° C., for 20 minutes to 6 hours, preferably 30 minutes to 3 hours.

  In the radiation graft polymerization method, it is preferable to irradiate the base material for grafting under an inert gas atmosphere such as nitrogen gas, and the irradiation amount is 10 to 300 kGy, preferably 50 to 200 kGy. When the irradiation amount is less than 10 kGy, the generated radical density is small, and the ultimate graft ratio is small. On the other hand, when the irradiation dose exceeds 300 kGy, the deterioration of the substrate becomes significant.

  As the organic polymer base material used in the present invention, a polymer material fiber or an aggregate of the polymer material fiber capable of introducing a sulfonic acid group to the surface and inside of the substrate by a graft polymerization method, for example, a woven fabric And a nonwoven fabric, a net, a film, a porous membrane, etc. can be mentioned preferably.

  The polymer material fiber has a large surface area, high air permeability, can increase the removal rate of trace ions, and is lightweight and easy to mold. Specific examples of the shape of the polymer material fiber include long fibers and processed products thereof, short fibers and processed products thereof, and cut short bodies thereof. Examples of the long fiber include a continuous filament, and examples of the short fiber include a staple fiber. Various woven fabrics and non-woven fabrics manufactured from the long fibers and short fibers of these polymer materials are lightweight and can be easily processed into a desired shape such as a mask, and are suitable for use in the present invention. Also, a combination of multiple types of polymer fiber materials can be used. For example, in order to give strength, a composite material fiber using polyethylene terephthalate having a polyester-based bond in the core and polyethylene on the surface Can also be used.

Examples of the porous film include a porous polymer film or a porous molecular film containing an inorganic substance. As a form of the porous membrane substrate, either a porous flat membrane or a hollow fiber membrane can be applied.
As the organic polymer base material that can be used in the present invention, those capable of graft-polymerizing monomers by a radiation graft polymerization method are particularly preferable. Polyolefins such as polyethylene and polypropylene, PTFE, polyvinyl chloride and the like. Olefin-halogenated such as halogenated polyolefin, polyester, polyether, cellulose, and copolymers thereof such as ethylene-tetrafluoroethylene copolymer and ethylene-vinyl alcohol copolymer (EVA) Mention may be made of olefin copolymers. In particular, polyolefin-based or halogenated polyolefin-based polymers or copolymers that do not exhibit disintegration with respect to radiation are preferable.

  In the present invention, the sulfonic acid group introduced into the organic polymer substrate by the graft polymerization method is obtained by directly introducing a polymerizable monomer having a sulfonic acid group (graft monomer) into the organic polymer substrate by graft polymerization. Alternatively, it may be one obtained by first graft-polymerizing a polymerizable monomer capable of introducing a sulfonic acid group and then introducing it by sulfonation.

  Examples of the polymerizable monomer having a sulfonic acid group include sodium sulfonates such as sodium styrene sulfonate, sodium vinyl sulfonate, sodium methallyl sulfonate, and free (H-type) monomers thereof. Can do.

  In addition, polymerizable monomers that do not have sulfonic acid groups themselves but are capable of introducing sulfonic acid groups include glycidyl methacrylate (GMA), styrene, acrylonitrile, acrolein, chloromethyl styrene, bromomethyl styrene. Etc. As a method of introducing a sulfonic acid group after graft polymerization of a polymerizable monomer capable of introducing these sulfonic acid groups, a known method can be employed. For example, after graft polymerization of styrene, sulfonic acid groups can be introduced onto the polymer side chain by reacting with sulfuric acid or chlorosulfonic acid for sulfonation. After the introduction of the sulfonic acid group, the sodium type sulfonate can be converted to a free sulfonic acid by acid treatment.

  In the present invention, the polyamine layer is one or more selected from the group consisting of a sulfonic acid group and a primary amino group, a secondary amino group, a tertiary amino group, and a quaternary ammonium group on the surface of the core layer. A primary amino group, a secondary amino group, a tertiary amino group and a primary amino group which are immobilized on the surface of the core layer by an acid-base bond with a basic functional group and which are not bonded to the sulfonic acid group. It has at least one free basic functional group selected from the group consisting of quaternary ammonium groups and a primary amino group, and mainly constitutes an adsorption site for aldehydes and an adsorption site for acid gases. Here, the primary amino group constitutes an adsorption site for aldehydes that take in aldehyde to form imine. One or more free basic functional groups selected from the group consisting of a primary amino group, a secondary amino group, a tertiary amino group, and a quaternary ammonium group that are not bonded to a sulfonic acid group are: Constitutes an acid gas adsorption site. In the present invention, the basic functional group constituting the acidic gas adsorption site is particularly preferably a quaternary ammonium group having the strongest basicity.

  As the polyamine compound that can be used in the present invention, any of an aromatic polyamine and an aliphatic polyamine may be used.

Polyallylamine of the formula

Polyethyleneimine, following formula

Polyvinylamine having a large amount of basic functional groups can be preferably used.
In the present invention, the polyamine compound is mainly present on the surface of the core layer but not in the core layer. The polyamine layer is bonded to the primary amino group and the sulfonic acid group on the surface of the core layer. One or more basic functional groups selected from the group consisting of a primary amino group, a secondary amino group, a tertiary amino group and a quaternary ammonium group, and a primary amino group which is not bonded to a sulfonic acid group And one or more basic functional groups selected from the group consisting of a secondary amino group, a tertiary amino group, and a quaternary ammonium group. In particular, in the present invention, since it is necessary for the primary amino group constituting the aldehyde adsorption site to be present in the polyamine layer, the polyamine compound preferably contains a large amount of primary amino groups.

  Further, since the polyamine compound penetrates into the core layer depending on the molecular weight, it is preferable that the polyamine compound has a relatively high molecular weight within a range in which the polyamine compound does not penetrate excessively. However, the molecular weight of the polyamine compound penetrating into the core layer depends on the shape of the organic polymer base material forming the core layer (fiber density, pore size of the porous membrane, etc.). It varies depending on the material. On the other hand, if the molecular weight is too high, the viscosity of the polyamine compound becomes high and handling becomes difficult. Therefore, the molecular weight is preferably in a range that does not penetrate into the core layer and the viscosity does not become too high, and the number average molecular weight (Mw) is preferably in the range of about 1,000 to about 100,000, and about 5 Particularly preferred is a molecular weight in the range of 20,000 to about 20,000.

  The polyamine compound is introduced by dissolving the polyamine compound in an organic solvent such as water or alcohol, or a mixed solvent thereof to obtain a polyamine compound solution, and the organic polymer base material into which the sulfonic acid group is introduced is added to this solution. It can be carried out by immersing and then washing with water to remove excess polyamine compound solution and drying by hot air drying or the like.

  The two-layer aldehyde, acid gas and basic gas removal material of the present invention has an aldehyde adsorption site, an acid gas adsorption site and a basic gas adsorption site, and effectively adsorbs and removes these toxic substances. Since the substrate is not particularly limited, it can be used for various applications. For example, filters used for equipment that actively circulates air such as air conditioners and air purifiers, interior materials that passively contact air, such as walls and flooring, masks, mask filters, etc. Can do. In particular, when a non-woven fabric having appropriate voids is used as the substrate, it is excellent in air permeability and therefore suitable as a filter material.

  In addition, according to the present invention, a core layer forming step of forming a core layer including an organic polymer substrate having a sulfonic acid group by introducing a sulfonic acid group into the organic polymer substrate by graft polymerization is formed. From the group consisting of primary amino group, secondary amino group, tertiary amino group and quaternary ammonium group on the sulfonic acid group on the surface of the core layer by reacting the core layer with the polyamine compound. From the group consisting of one or more selected basic functional groups and a sulfonic acid group and an unbound primary amino group, secondary amino group, tertiary amino group, and quaternary ammonium group. A two-layer aldehyde, acid gas and basic gas removal comprising a polyamine layer forming step of forming a polyamine layer having one or more basic functional groups selected and a primary amino group Provided by material manufacturing method It is.

Preferred embodiment

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these.

As an organic polymer base material into which a sulfonic acid group is introduced, a basis weight of 26 g / m ² composed of a composite fiber of polyethylene terephthalate (PET) (core) / polyethylene (PE) (sheath) having a fiber diameter of 15 μm and a thickness of 0.13 mm A heat-sealed nonwoven fabric was used. This nonwoven fabric substrate is cut into 10 cm square, irradiated with 150 kGy electron beam in a nitrogen gas atmosphere, then immersed in 100% glycidyl methacrylate (GMA) solution, and impregnated with 96% GMA monomer of the nonwoven fabric weight. I let you.

  Subsequently, the nonwoven fabric impregnated with the GMA monomer was transferred to an ampoule and vacuum suctioned to 6.7 hPa with a vacuum pump, and then the ampoule was placed in a 45 ° C. constant temperature bath and reacted for 4 hours. The GMA graft polymerization nonwoven fabric of this was obtained.

The obtained GMA graft polymerization nonwoven fabric was immersed in a sulfonated solution (an aqueous solution containing 8% sodium sulfite and 12% isopropyl alcohol) and reacted for 10 hours to be sulfonated. The sodium salt of the obtained sulfonated product was made free with a 5% aqueous hydrochloric acid solution, and then the neutral salt decomposition capacity was measured using an aqueous sodium chloride solution. As a result, it was 185 meq / m ² .

  This non-woven fabric was again made free (H-type) with a large excess of 5% aqueous hydrochloric acid, and further washed and dried to prepare a non-woven fabric into which sulfonic acid groups were introduced (hereinafter simply referred to as “core layer”). .

  Next, the obtained core layer is immersed in 60 ml of an aqueous solution of 1% polyethyleneimine (trade name: Epomin SP-200, manufactured by Nippon Shokubai) for about 5 minutes while being turned over several times to bind to the sulfonic acid groups on the surface of the core layer. Thus, an adsorption material having a two-layer structure composed of the core layer and the polyamine layer of the present invention was obtained.

  Subsequently, the adsorbing material was taken out, immersed in 150 ml of pure water, washed by stirring for about 5 minutes, and the electrical conductivity of the cleaning liquid was measured. The washing was repeated until the electric conductivity of the washing liquid decreased to about pure water. In this example, cleaning was required 5 times until the electric conductivity of pure water reached 0.7 μS / cm. The adsorbed material after washing was dried in a dryer at 50 ° C. for 2 hours, and then dried in a constant temperature vacuum dryer at 50 ° C. for 3 hours. After drying, when the weight of the adsorbent material was measured, it was found that 20.5 mg of polyethyleneimine was immobilized.

[XMA analysis]
The structure of the adsorbing material prepared in Example 1 was confirmed by analyzing the element distribution with an X-ray microanalyzer (XMA).

  The adsorbing material prepared in Example 1 was dipped in 0.5 mol / l of hydrochloric acid for 2 hours or more, then washed with pure water to remove excess hydrochloric acid and dried, and the amino group of polyethyleneimine was converted into a hydrochloride type sample. It was. Next, when carbon was vapor-deposited on this sample and the element distribution by XMA was analyzed with respect to the fiber cross section, sulfur was distributed to the inside of the base fiber, but chlorine was mainly present only on the base fiber surface. I understood. Sulfur is derived from a sulfonic acid group, and it can be said that the sulfonic acid group is added to the inside of the base fiber. Chlorine is derived from the hydrochloride of the amino group of the polyamine compound, and it can be said that the amino group remains on the surface of the base fiber. That is, it was found that the adsorbing material of the present invention prepared in Example 1 has a two-layer structure of a core layer into which sulfonic acid groups are introduced and a polyamine layer into which amino groups are introduced.

[Formaldehyde removal performance test]
The adsorbing material prepared in Example 1 was placed in a 10-liter gas sampling aluminum bag and filled with 10 liters of nitrogen gas. On the other hand, 40 ml of formaldehyde solution was put in a 100 ml glass ampule bottle and sealed, and left at room temperature for 2 hours or more. Then, 10 ml of gas was extracted from the head space of the ampule bottle using a gas tight syringe, The sample was poured into an aluminum bag for gas sampling.

  The formaldehyde concentration in the aluminum bag was measured periodically using a detector tube (product number: No. 91L, manufactured by Gastec). As a control, a gas sampling aluminum bag not filled with an adsorbing material was prepared, and formaldehyde was injected in the same manner to measure the natural decrease of formaldehyde in the aluminum bag. The results are shown in Table 1. In the table, “immediately after injection” means a point in time of 6 minutes from the injection to the end of measurement.

  From Table 1, it can be seen that the adsorbing material of the present invention has a sufficient removal effect on formaldehyde.

[Ammonia removal performance test]
The adsorbing material prepared in Example 1 was placed in a 10-liter gas sampling aluminum bag and filled with 10 liters of nitrogen gas. On the other hand, 10 ml of 25% ammonia water is put into a 100 ml glass ampoule bottle, tightly stoppered, and left for 2 hours or more. Then, 200 μl of gas is extracted from the head space of the ampoule bottle using a gas tight syringe, and adsorbing material is contained. It was injected into an aluminum bag for gas sampling.

  The ammonia concentration in the aluminum bag was measured periodically using a detector tube (product number: No. 3L, manufactured by Gastec). As a control, a gas sampling aluminum bag not filled with an adsorbing material was prepared, and ammonia was injected in the same manner to measure the natural decrease of ammonia in the aluminum bag. The results are shown in Table 2. In the table, “immediately after injection” means a point in time when one minute has elapsed from the injection to the end of measurement.

  From Table 2, it can be seen that the adsorbing material of the present invention has a sufficient removal effect on ammonia.

[Acetic acid removal performance test]
The adsorbing material prepared in Example 1 was placed in a 10-liter gas sampling aluminum bag and filled with 10 liters of nitrogen gas. On the other hand, 10 ml of acetic acid was put in a 100 ml glass ampoule bottle and sealed, and left for 2 hours or more. Then, 2.5 ml of gas was extracted from the head space of the ampoule bottle using a gas tight syringe, and adsorbing material was contained. It was injected into an aluminum bag for gas sampling.

  The acetic acid concentration in the aluminum bag was periodically measured using a detector tube (product number: No. 81, manufactured by Gastec). As a control, a gas sampling aluminum bag not filled with an adsorbing material was prepared, and acetic acid was injected in the same manner to measure the natural decrease of acetic acid in the aluminum bag. The results are shown in Table 3. In the table, “immediately after injection” means a point in time when one minute has elapsed from the injection to the end of measurement.

From Table 3, it can be seen that the adsorbing material of the present invention has a sufficient removal effect on acetic acid.
From the results of Examples 3 to 5, it can be said that the adsorbing material of the present invention exhibits an excellent adsorption removal effect on aldehydes typified by formaldehyde, basic gas typified by ammonia, and acid gas typified by acetic acid. .

FIG. 1 is a schematic diagram showing a basic conceptual structure of the adsorbing material of the present invention.

Explanation of symbols

1: Core layer in which sulfonic acid group is introduced 2: Polyamine layer

Claims (4)

A core layer comprising an organic polymer substrate having a sulfonic acid group introduced into and inside the organic polymer substrate by a pre-irradiation radiation graft polymerization method;
A sulfonic acid group on the surface of the core layer, and one or more basic functional groups selected from the group consisting of a primary amino group, a secondary amino group, a tertiary amino group, and a quaternary ammonium group; Are fixed to the surface of the core layer by bonding, and further from a group consisting of a sulfonic acid group and an unbonded primary amino group, secondary amino group, tertiary amino group, and quaternary ammonium group. A polyamine layer having one or more basic functional groups selected and a primary amino group;
Including a two-layer structure of
The sulfonic acid group of the core layer constitutes a basic gas adsorption site, the basic functional group of the polyamine layer bonded to the sulfonic acid group constitutes an aldehydes adsorption site, and the basic group that is not bonded to the sulfonic acid group. Aldehyde, acid gas and basic gas removal material, wherein the functional group constitutes an acid gas adsorption site.   The aldehydes according to claim 1, wherein the organic polymer substrate is a polymer material fiber or an aggregate of the polymer material fibers, and a sulfonic acid group is introduced into the surface and inside of the substrate. Acid gas and basic gas removal material. A core layer forming step of introducing a sulfonic acid group into and on the surface of the organic polymer substrate by pre-irradiation radiation graft polymerization to form a core layer containing the organic polymer substrate having a sulfonic acid group;
The formed core layer is reacted with a polyamine compound, and the sulfonic acid group on the surface of the core layer is composed of a primary amino group, a secondary amino group, a tertiary amino group, and a quaternary ammonium group. One or more basic functional groups selected from the group are bonded, and the sulfonic acid group and the unbonded primary amino group, secondary amino group, tertiary amino group, and quaternary ammonium group are included. A polyamine layer forming step of forming a polyamine layer having one or more basic functional groups selected from the group and a primary amino group;
Including
The sulfonic acid group of the core layer constitutes a basic gas adsorption site, the basic functional group of the polyamine layer bonded to the sulfonic acid group constitutes an aldehydes adsorption site, and the basic group that is not bonded to the sulfonic acid group. A method for producing a double-layered aldehyde, acidic gas and basic gas removing material, wherein the functional group constitutes an acidic gas adsorption site. The method according to claim 3 , wherein the organic polymer base material is a polymer material fiber or an aggregate of the polymer material fibers.

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