JP2002096425A - Water absorber and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water absorber having a small weight/volume during conveying/moving and having a large weight/volume during use by absorbing water to function as a soil. SOLUTION: The water absorber 1 comprises a water absorbing material 3 made of a water absorbing polymer in powder form contained in a water permeable bag body 2. The water absorbing material 3 is prepared, for example, by an acid treatment with concentrated sulfuric acid of a powdered ABS resin waste material containing carbon black. This water absorbing material 3 is a modified polymer showing a gel state by absorbing water, and preferably contains a surfactant. The water permeable bag body 2 is, for example, of a thick cotton cloth impregnated with sodium laurylsulfate as a surfactant. Preferably the water permeable bag body 2 contains a water absorbing material 3 and a metal powder having a magnetic property.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water absorbing body used for removing unnecessary water remaining due to water leakage, flooding, etc., and a sandbag used for raising and embankment of a dike in a flood of a river and for preventing and repairing a collapse. The present invention relates to a water absorbing body having a function.

[0002]

2. Description of the Related Art A fibrous material such as cloth has conventionally been used as a water absorbent used for removing unnecessary water remaining due to water leakage, flooding, and the like. The water-absorbing body having the function of a sandbag is a civil engineering material that prevents flooding of rivers, lakes, and marshes due to flooding or the like. A conventional water-absorbing body having the function of a sandbag is prepared by putting soil in a hemp bag, for example. In this case, the water absorbing body having the function of a sandbag is difficult to be transported due to its large weight and volume, and is generally produced near a disaster site. When transporting from a distance, it must be transported using a vehicle or the like, and it is difficult to transport and unload. In the event of a disaster, it is necessary to quickly apply a water absorber having the function of a sandbag to a necessary place when necessary. This allows
Human life and property can be protected from flood damage.

[0003]

As described above, a water absorber used to remove unnecessary water remaining due to water leakage, flooding, or the like, or a water absorber having a sandbag function, has a large weight and volume and requires much labor for transportation. It costs. For this reason, conventionally, there has been a demand for a water absorber that is small in weight, small in volume, and easy to carry.

Accordingly, an object of the present invention is to provide a water absorbing body satisfying the above requirements and a method for producing the same. That is, the first object of the present invention is to reduce weight and weight during transportation.
To provide a water absorber having a small volume, absorbing water when used, increasing weight and volume, having a high ability to follow the shape of the outer shape, and having a function of removing unnecessary water, or a function of sandbags. is there. A second object of the present invention is to provide a water absorber that can be used repeatedly. Further, a third object of the present invention is to contribute to the improvement of the global environment by effectively utilizing waste polymer or inorganic solid waste that has been difficult to treat.

[0005]

Means for Solving the Problems In order to achieve the above object, a water absorbent according to the present invention comprises a powdery, granular or other small water-absorbent polymer (water-absorbent resin) formed from a water-permeable bag. A water-absorbent body encapsulated in the bag-shaped body (enclosed in the bag-like body), wherein the water-absorbing polymer is obtained by acid-treating a polymer material containing acrylonitrile and styrene and / or conjugated diene,
A modified polymer that exhibits a gel state by water absorption, wherein at least one of the water-permeable bag-like body and the water-absorbing polymer contains a surfactant. The polymer material contains acrylonitrile, at the same time, styrene,
It contains at least one of conjugated dienes (Claim 1).

As the water absorbing body, it is preferable that the water-permeable bag-like body contains, in addition to the water-absorbing polymer, a small solid such as powder or granule having a specific gravity of 1 or more. The surfactant is preferably an anionic surfactant and / or a nonionic surfactant. Further, regarding the content of the surfactant, the water-absorbing polymer 10 in a dry state was used.
It is preferable that the content of the surfactant with respect to 0 parts by weight and the content of the surfactant with respect to 100 parts by weight of the water-permeable bag in a dry state are each 0.01 to 10 parts by weight, It is particularly preferred that the content be 0.1 part by weight or more and 5 parts by weight or less. When the content of the surfactant is larger than the upper limit described above, the surfactant is released from the water-absorbing polymer and the water-permeable bag when the water-absorbing body enters a water-absorbing state, and contaminates the outside. There is a fear and it is not preferable. On the other hand, when the content of the surfactant is smaller than the lower limit described above, the effect of improving the water absorption of the water-absorbing polymer and the water-permeable bag by the surfactant (increase in water absorption rate) cannot be obtained.

The polymer material preferably contains acrylonitrile units in an amount of 5 mol% or more and 80 mol% or less, more preferably 10 mol% or more and 60 mol% or less of acrylonitrile units. It is particularly preferred that the content be at least 50 mol%. The polymer material may contain styrene and / or conjugated diene units in an amount of 20 mol% to 95 mol%.
The styrene and / or conjugated diene unit is more preferably contained in an amount of 40 mol% or more and 85 mol% or less, and the styrene and / or conjugated diene unit is preferably contained in an amount of 50 mol% or more and 80 mol% or less. Especially desirable.

Further, it is preferable that the polymer material contains carbon black or titanium oxide. Further, it is preferable that the water-absorbing polymer (modified polymer) is a polymer starting from a waste polymer material containing acrylonitrile and styrene and / or conjugated diene.

In order to achieve the above object, a method for producing a water absorbent according to the present invention is directed to a method for producing a water absorbent comprising a water-permeable bag-like body containing a powdery, granular or other small water-absorbent polymer. A method for producing a water-absorbing polymer, which is a modified polymer that exhibits a gel state by absorbing water by subjecting a small polymer material containing acrylonitrile and styrene and / or conjugated diene to acid treatment. After that, the small water-absorbent polymer is sealed in a water-permeable bag, and the surfactant is added to at least one of the water-absorbent polymer and the water-permeable bag before the sealing step. It is characterized in that it is contained (claim 14).

In this manufacturing method, it is preferable that the small water-absorbent polymer and a small solid such as powder or granule having a specific gravity of 1 or more are sealed in the water-permeable bag. Further, it is preferable that the small-sized polymer material contains carbon black or titanium oxide. The surfactant is preferably an anionic surfactant and / or a nonionic surfactant. The amount of the surfactant added to the water-absorbing polymer and the water-permeable bag is preferably within the above range. Further, it is preferable that the water-absorbing polymer (modified polymer) is a polymer starting from a waste polymer material containing acrylonitrile and styrene and / or conjugated diene. Further, as the polymer material, a material in which the acrylonitrile unit and the mol% of the styrene and / or conjugated diene unit are within the above-mentioned ranges is preferable.

With the above construction, the weight / volume is small when transported, the weight / volume is increased by absorbing water when used, and the shape of the water absorbent or sandbag which removes unnecessary water is high, since the external shape is highly conformable. A water absorber having a function can be provided. In addition, by increasing the water absorbing speed of the water absorbing body, it is possible to cope with urgency in use. Also,
Utilizing polymer waste or inorganic solid waste, which has been difficult to treat, as a resource can contribute to improving the global environment.

[0012]

Embodiments of the present invention will be described in detail with reference to the drawings. Hereinafter, a water absorbing body to which the present invention is applied and which removes unnecessary water or has a function as a sandbag will be described.

First Embodiment FIG. 1 is a schematic sectional view showing a structure of a water absorbing body.
(A) shows the state before use (before water absorption, that is, at the time of shipment),
(B) shows the state at the time of use (at the time of water absorption). In FIG. 1, reference numeral 1 denotes a water absorbing body, reference numeral 2 denotes a water-permeable bag-like body, reference numeral 3 denotes a water absorbing material, reference numeral 3a denotes a water absorbing material before water absorption, and reference numeral 3b denotes a water absorbing material after water absorption. Each is shown.

The water-absorbing body 1 shown in FIG. 1A comprises a bag-like body 2 and a water-absorbing material 3a. That is, the water-absorbing body 1 is made of a water-permeable bag 2 containing a surfactant as needed, and a high-capacity bag containing acrylonitrile, styrene and / or conjugated diene contained in the bag 2. A water-absorbing material 3a made of a water-absorbing polymer (denatured polymer) obtained by acid-treating a molecular material;
And a water-absorbing material 3a composed of the modified polymer (water-absorbing polymer) and a surfactant.

Second Embodiment FIG. 2 is a schematic sectional view showing a structure of a water absorbing body 11,
(A) shows the state before use (before water absorption, that is, at the time of shipment),
(B) shows the state at the time of use (at the time of water absorption). In FIG. 2, reference numeral 4 denotes a solid having a specific gravity of 1 or more. As described above, the water absorbing body 11 of the present embodiment has the
In which the water-absorbing material 3a and the solid 4 are included. The other points are the same as in the first embodiment.

The polymer material (the water-absorbing polymer, ie, the starting material of the water-absorbing resin) constituting the water-absorbing bodies 1 and 11 contains acrylonitrile and at least one of styrene and conjugated diene. In this polymer material, acrylonitrile, styrene and / or
Alternatively, the content ratio of the conjugated diene (such as butadiene and isoprene) is preferably in the following ranges.

That is, the polymer material preferably contains acrylonitrile units in an amount of 5 mol% to 80 mol%, more preferably 10 mol% to 60 mol%, and more preferably 20 mol% or less. 50% or more
It is particularly preferred that the content be at most mol%. When the content of the acrylonitrile unit is less than 5 mol%, the composition becomes water-soluble after the acid treatment, and cannot be used as a water-absorbing resin. On the other hand, if the content of acrylonitrile units exceeds 80 mol%, the polymer material becomes hard and difficult to pulverize into small pieces, or the content of styrene and / or conjugated diene in the polymer material decreases. Since the result is too small and the introduction ratio of the hydrophilic group also decreases, the water absorption effect (particularly for the aqueous electrolyte solution) also decreases.

The polymer material preferably contains styrene and / or a conjugated diene unit in an amount of 20 mol% to 95 mol%, and the unit is contained in an amount of 40 mol% to 8 mol%.
More preferably, the content is 5 mol% or less.
It is particularly preferable that the content is 0 mol% or more and 80 mol% or less.

By performing the acid treatment of the present invention, an ionic acidic group is introduced into the polymer material, so that the structural units of the styrene and / or conjugated diene are converted to the water-absorbing resin of the resulting water-absorbing resin. (Especially for an aqueous electrolyte solution). As long as acrylonitrile and styrene and / or conjugated diene are contained at predetermined ratios, further constituent units may be contained in the polymer material.

Examples of the other structural units include maleic anhydride, itaconic anhydride, α-methylstyrene, acrylamide, methacrylamide, acrylic acid, and acrylates (saturated and unsaturated hydrocarbons having 1 to 10 carbon atoms). ), Methacrylic acid, methacrylic acid esters (saturated and unsaturated hydrocarbons having 1 to 10 carbon atoms), vinyl acetate, ethylene, propylene, butylene,
Vinylpyrrolidone, vinylpyridine and the like.

As the above-mentioned polymer material, those having a weight average molecular weight (Mw) of 1,000 to 20 million can be used, but 10,000 to 1 million are generally used. When the molecular weight is lower than 1,000, the compound becomes water-soluble upon acid treatment, and an intended water-absorbing resin cannot be obtained. On the other hand, when the molecular weight is higher than 20,000,000, the reaction rate at the time of the acid treatment becomes slow, which is not practical.

As the polymer material containing acrylonitrile and styrene and / or conjugated diene, ABS resin, SAN resin, ASA resin, ACS resin, NBR rubber and the like are preferable. These materials may be newly-produced virgin pellets, resin raw materials or discharged products (semi-products) in the process of producing molded products, housings used in electric products and automobiles, and various other products. It may be a component material or a used waste material molded for a specific use from a tube, a hose, or various cushioning materials. The discharge location may be any of factories, stores, households, etc., but those collected from factories, stores, etc. have relatively more composition than general waste from homes, etc. It is more desirable because there are many things.

The polymer material may be an alloy with another resin, and may be a waste material containing additives such as a facial dye, a stabilizer, a flame retardant, a plasticizer, a filler, and other auxiliary agents. It may be. Further, it may be a mixture of used waste material and virgin material.

The other resin which can be mixed with the polymer material is preferably a resin which does not inhibit the acid treatment of the present invention. Examples of the resin include polyphenylene ether, polycarbonate, polyphenylene sulfide, polyethylene terephthalate, polybutylene terephthalate, and the like. Polyamide and the like can be mentioned. These resins are desirably mixed at 60% by weight or less with respect to the polymer material. If the content of these resins is too large, the acid treatment reaction will be inhibited.

It is desirable that the above-mentioned polymer material is made into small pieces before the acid treatment. There are the following methods for making small pieces. (1) After crushing with a crusher, sieving is performed. When the polymer material contains a rubber component, it is preferable to pulverize after freezing. (2) Heat and melt to pelletize into fine beads. In addition, it is desirable that the size of the high molecular material of the above small piece is smaller than 3.5 mesh. If the size is larger than this diameter, the surface area of the polymer material becomes small, so that the acid treatment does not proceed smoothly and the reaction time is long, which is not practical, and the function as a water absorbing resin (water absorbing function) is greatly reduced. Will be.

When the following inorganic pigment (carbon black, titanium oxide) is contained in the polymer material of the present invention, the periphery of the inorganic pigment is easily acid-treated, and the acid treatment is accelerated. That is, at the time of the acid treatment reaction, the inorganic pigment separates from the polymer material and the acid easily penetrates the surface of the polymer material, so that the water absorbing effect of the water absorbent resin is improved. Carbon black and titanium oxide may be those originally contained in the above-mentioned polymer material, or may be those added to and mixed with the polymer material. The water absorption performance of the resin is improved. These carbon blacks and titanium oxides may be those generally used as a coloring agent, a reinforcing agent and an electric conductivity imparting agent for plastics.

The carbon black may be produced by any of the channel method, the furnace method, and the thermal method, and each of them may be used alone or two or more of them may be used in combination. The average particle size of the carbon black is usually 0.005 μm or more and 100 μm or more.
mμ or less, preferably from 0.01 to 10 mμ. The titanium oxide may be any of rutile-type, anatase-type, and ultrafine-particle titanium, and may be used alone or in combination. The average particle diameter of titanium oxide is usually 0.01 m
μm to 50 mμ, but 0.05 mμ to 10 m
μ or less is preferred. The amount of carbon black or titanium oxide contained in the water-absorbent resin is generally from 0.01% by weight to 20% by weight based on the dry weight of the water-absorbent resin, but is preferably from 0.05% by weight to 10% by weight. % Or less is preferable.

In the method for producing a water absorbent according to the present invention, acrylonitrile and one of styrene and / or conjugated diene are used.
Conversion to a water-absorbing resin is performed by acid-treating a polymer material containing at least one of the above as a constituent unit. That is, by the acid treatment, a part of acrylonitrile in the polymer material is hydrolyzed, and an ionic group is introduced into styrene or conjugated diene.

The acid used in the acid treatment is preferably an inorganic acid. The amount (weight) of the inorganic acid to be charged is at least 1 and at most 500 times the weight of the polymer material, preferably at least 10 and at most 200 times. If the amount of the inorganic acid is less than the weight of the polymer material, the introduction rate of ionic groups to styrene and conjugated diene and the hydrolysis rate of acrylonitrile groups decrease, and the properties (water absorption effect) of the water absorbent resin decrease. . Also, the amount of the inorganic acid charged is 50% of the polymer material.
If it is more than 0 times, it becomes necessary to neutralize the excess inorganic acid, which is disadvantageous both economically and operationally.

Examples of the inorganic acids include sulfonating agents such as concentrated sulfuric acid, sulfuric anhydride, fuming sulfuric acid and chlorosulfonic acid, and nitric acid, fuming nitric acid, phosphoric acid, phosphorus chloride, phosphorus oxide and the like. Among these, concentrated sulfuric acid, sulfuric anhydride, fuming sulfuric acid, and chlorosulfonic acid are preferred, and concentrated sulfuric acid having a concentration of 70% by weight or more is particularly preferred. These inorganic acids may be used alone or in combination of two or more. When used in combination, they may be mixed or added sequentially. For example,
By first treating the polymer material with concentrated sulfuric acid and then adding sulfuric anhydride, a water-based, shape-stable water-absorbing resin can be obtained. This is because the treatment with concentrated sulfuric acid first hydrolyzes the nitrile portion in the polymer material, and then the treatment with sulfuric anhydride causes the styrene or conjugated diene portion to be forcibly sulfone-crosslinked, and the degree of crosslinking is reduced. This is because a water-absorbent resin having a high water content is obtained.

The above acid treatment may be performed in an inorganic acid, or may be performed in a system using an organic solvent. Examples of usable organic solvents include C ₁ -C ₂ aliphatic halogenated hydrocarbons (preferably 1,2-dichloroethane, chloroform, dichloromethane, 1,1-dichloroethane) and aliphatic cyclic hydrocarbons (preferably cyclohexane). , Methylcyclohexane, cyclopentane), nitromethane, nitrobenzene, sulfur dioxide, paraffinic hydrocarbons (C1-7), acetonitrile, carbon disulfide, tetrahydrofuran, tetrahydropyran, 1,2-dimethoxyethane, acetone, methyl ethyl ketone, thiophene And the like. Preferred among the above organic solvents are C ₁ -C ₂ aliphatic halogenated hydrocarbons, aliphatic cyclic hydrocarbons, nitromethane, nitrobenzene, and sulfur dioxide. These solvents may be used alone or as a mixture of two or more. There is no particular limitation on the mixing ratio between the organic solvents.

The weight of these organic solvents is preferably less than 200 times the weight of the polymer material. When the addition amount of the organic solvent is larger than this, the reaction rate of the acid treatment becomes low and it is economically disadvantageous. In the acid treatment, a Lewis base may be used if necessary. Examples of the Lewis base include alkyl phosphate (triethyl phosphate, trimethyl phosphate), dioxane, acetic anhydride, ethyl acetate, ethyl palmitate, diethyl ether, thioxane, and the like. The inorganic acid or organic solvent once used in the above acid treatment may be recovered and used as it is after the completion of the reaction, or may be recovered by a method such as extraction or distillation and used again for the reaction.

In the present invention, by subjecting the above-mentioned polymer material to the above-mentioned acid treatment, an ionic group is introduced into the styrene and / or conjugated diene unit, and the acrylonitrile unit is amidated by a hydrolysis reaction, whereby the polymer material is amidated. Is converted to a water absorbent resin.

The ionic group introduced into the styrene or conjugated diene unit by the above acid treatment includes a sulfonic acid group and / or a salt thereof, —PO (OH) ₂ and / or a salt thereof, and —CH ₂ PO (OH) _2. and / or its salts, and -NO _2. In order to introduce a sulfonic acid group as an ionic group, a polymer material and a sulfonating agent such as concentrated sulfuric acid, sulfuric anhydride, fuming sulfuric acid, and chlorosulfonic acid may be reacted as they are or in a solvent. Further, the introduction of -PO (OH) ₂ group is possible by adding phosphorus trioxide to a solvent and further hydrolyzing. By reacting with a mixed solution of sulfuric acid and nitric acid, a —NO ₂ group can be introduced into the polymer material. In addition, in these ionic groups, a sulfonic acid group and / or a salt thereof are preferable. These ionic groups may be introduced alone into the polymer material, or two or more kinds may be introduced.

However, in order to satisfy the performance as a water-absorbing resin, the amount of the ionic group contained in the polymer material is from 5 mol% to 95 mol%, preferably 10 mol%, based on all units. It is at least 70 mol%. When the introduction ratio of the ionic group is higher than 95 mol%, the acid-treated product of the polymer material becomes water-soluble and cannot be used as a water-absorbing resin. When the introduction ratio of the ionic group is lower than 5 mol%, the water absorption effect (particularly for the aqueous electrolyte solution) is reduced.

By performing the above-mentioned acid treatment under the following conditions, it becomes possible to introduce a predetermined amount of ionic groups into the polymer material. The reaction temperature of the acid treatment varies greatly depending on whether or not an organic solvent is used, but is generally from 0 ° C to 200 ° C, preferably from 30 ° C to 120 ° C. If the reaction temperature is too low, the reaction rate becomes too slow to be practical, and a water-absorbing resin having good performance cannot be obtained. If the reaction temperature is too high, the molecular chains of the polymer material are easily cut (due to thermal decomposition) and dissolved in water. The reaction time varies greatly depending on the reaction temperature, but is generally from 1 minute to 40 hours, preferably from 5 minutes to 2 hours. If the reaction time is too short, the reaction does not proceed sufficiently. On the other hand, if it is too long, the production efficiency deteriorates.

In order to wash the reaction product obtained by the acid treatment, for example, the reaction product is directly added to a large amount of water or a basic aqueous solution, or the reaction product is filtered through a filter or the like.
The filtered solid is poured into a large amount of water or a basic aqueous solution. In these washing treatments, the nitrile groups in the polymer material are converted into amide groups or carboxyl groups and / or salts thereof. Examples of the basic substance used in the basic aqueous solution include oxides, hydroxides, carbonates, and acetates of alkali metals (such as sodium, lithium, and potassium) and alkaline earth metals (such as magnesium and calcium). Sulfates,
Compounds such as phosphates are exemplified. However, in order to improve the water-absorbing effect of the water-absorbing resin (particularly with respect to the aqueous electrolyte solution) and the deodorizing effect of ammonia gas and the like, it is desirable to perform only water washing without neutralization. The reaction product obtained as described above is in the form of a gel, and thereafter, by drying in the sun, heating, reduced pressure, centrifugation, pressing, and the like, the desired water-absorbing resin can be obtained.

By the treatment method described above, a water-absorbent resin having a nitrile group, the above-mentioned hydrolyzate, and an ionic group can be obtained. The water-absorbent resin has an unreacted nitrile group, thereby improving water-insolubility and gel strength. In addition, the water-absorbent resin absorbs water due to a nitrile group hydrolyzate and an ionic group (particularly with respect to an aqueous electrolyte solution). Is enhanced.

In the present invention, anionic surfactants, cationic surfactants, nonionic surfactants, and zwitterionic surfactants can be used as appropriate as the surfactant. Examples of anionic surfactants include fatty acid salts, higher alcohol sulfates, liquid fatty oil sulfates, sulfates of aliphatic amines and aliphatic amides, fatty alcohol phosphates, and sulfonates of dibasic fatty acid esters. Acid salts, fatty acid amide sulfonates, formalin condensed naphthalene sulfonates, and the like.

Examples of the cationic surfactant include an aliphatic amine salt, a quaternary ammonium salt, an alkylpyridinium salt and the like. As nonionic surfactants,
Examples include polyoxyethylene alkyl ether, polyoxyethylene alkyl phenol ether, polyoxyethylene alkyl ester, sorbitan alkyl ester, polyoxyethylene sorbitan alkyl ester, and the like.

Of the above surfactants, anionic surfactants and / or nonionic surfactants are preferably used. Thereby, it is possible to prevent the ionic groups formed on the water-absorbent resin, in particular, the hydrophobicity of the ionic groups due to the formation of the salt of the organic cation of the acid group and the surfactant, and to prevent a decrease in the water absorption of the water-absorbent resin. it can.

As a material of the water-permeable bag 2 of the present invention, a cloth of natural fibers or synthetic fibers is used. Examples of the natural fiber include cotton, hemp, and silk. Examples of the synthetic fibers include polyamide, polyimide, polyester, polyethylene, and polypropylene. It is preferable that these fibers are used alone or mixed and knitted into a cloth. However, in some cases, it may be a non-woven fabric or a film formed with pores penetrating the front and back.

Examples of the solid having a specific gravity of 1 or more according to the present invention include those composed of natural minerals, those composed of waste, and those formed by binding waste. Examples of these materials include metal, ceramics, glass, and materials obtained by binding these to each other. For the binding, a polymer material having a specific gravity of 1 or less can be used.

Further, in the present invention, a magnetic substance having a specific gravity of 1 or more may be used.
As those having magnetism, ferrimagnetic, ferromagnetic,
Those having parasitic magnetism are mentioned. Due to this magnetism,
The sandbag can be magnetically sucked and moved and transported by a crane or the like. This magnetism makes it possible to identify the sandbag. As the ferromagnetic material, iron,
Nickel, cobalt or alloys thereof, alloys containing them, transition metals and their alloys, and alloys containing rare earth elements can be mentioned. Furthermore, as ferrimagnetic material, magnetite,
Maghemite, hematite, manganese zinc ferrite,
Examples include manganese nickel ferrite, barium ferrite, and strontium ferrite. According to these, it is possible to greatly increase the weight of the sandbag as compared with a general inorganic material, and it is possible to increase the overall weight of the sandbag even in a water-absorbing state. In addition, these materials are members that are difficult to process in the disassembly process of the electronic device, and thus are useful from the viewpoint of effective utilization.

[0045]

EXAMPLES Examples of the water absorbent according to the present invention and comparative examples will be described. Note that the present invention is not limited to this embodiment. Example 1 A thick cotton cloth bag impregnated with sodium lauryl sulfate as a surfactant was prepared. On the other hand, 100 parts by weight of the water-absorbing material prepared as described below was prepared by adding 1 part by weight of sodium lauryl sulfate, and this was put in the above bag and sealed to prepare a water absorbent.

[Preparation of Water Absorbent Material] In 30 parts by weight of concentrated sulfuric acid (96% by weight), 1 part by weight of a powdery ABS resin waste material was added and reacted at 80 ° C. for 20 minutes. This powdery waste material was obtained from the black portion of an 8 mm cassette tape guard panel (52 mol% of styrene, 28 mol% of acrylonitrile,
A resin component consisting of 20 mol% of butadiene contains 2% by weight of carbon black. ) Was crushed by a frozen shredder and then classified.
Classification up to 2 mesh.

After completion of the above reaction, the solid matter in the system was filtered with a glass filter, washed with water, neutralized with 50 parts by weight of 1N sodium hydroxide solution, further washed with a sufficient amount of water, and filtered. Was taken out when the pH became 8 or less, and dried at 105 ° C. for 2 hours in a circulating drier. By this operation, a black solid was obtained. From the elemental analysis result of sulfur, it was confirmed that the sulfonic acid group in this solid was 33 mol% in all monomer units. Further, the content of sodium is almost equimolar to the sulfonic acid group (1.
1).

Example 2 A water absorbent was produced in the same manner as in Example 1 except that sodium lauryl sulfate was replaced by polyoxyethylene ether of myristyl alcohol.

Comparative Example 1 A water absorbent was produced in the same manner as in Example 1 except that neither sodium lauryl sulfate as a surfactant nor polyoxyethylene ether of myristyl alcohol was used.

The water-absorbing bodies of the same shape obtained in Examples 1 and 2 and Comparative Example 1 were placed on a uniform water surface having a depth of 1 cm, and the water-absorbing swelling speed was estimated from the change in the thickness of the water-absorbing bodies. Before immersion, the thickness was almost the same, but the thickness after one minute was 2.6 cm in Example 1 and 2.8 cm in Example 2, whereas the thickness in Comparative Example 1 was 1.6 cm. It was found that the water absorption rate was increased by using a surfactant.

[0051]

The water-absorbent body according to the present invention is a water-absorbent body comprising a water-absorbent polymer (a water-absorbent resin) in the form of small particles, such as powder or granules, contained in a water-permeable bag. The water-absorbing polymer is a modified polymer obtained by subjecting a polymer material containing acrylonitrile, styrene and / or conjugated diene to an acid treatment, and exhibiting a gel state by water absorption. Since it is characterized by containing a surfactant in at least one of the water-absorbing polymer, it can be effectively used to remove unnecessary water remaining in water leakage, flooding, etc., and particularly as a sandbag. It demonstrates excellent functions. Further, by adding a surfactant to the water-absorbing polymer, a decrease in the water-absorbing property of the water-absorbing polymer can be prevented. Furthermore, by adding a surfactant to the water-permeable bag, the water absorption of the bag is increased, so that the function as a sandbag is particularly improved.

The water-absorbing body of the present invention has a small weight and volume when it is not absorbing water, so that it can be easily transported and unloaded. This water absorbing body can be quickly applied. Further, the water absorbing body can be repeatedly used by drying the water absorbing body. Furthermore, since this water absorber can be made using high-polymer waste or inorganic solid waste that has been difficult to treat in the past, it must contribute to the effective use of resources and the improvement of the global environment. Can be.

Further, in the water-absorbent body of the present invention, the water-absorbent body has a structure in which, in addition to the water-absorbing polymer, a powdery, granular or other small-piece solid is included in the water-permeable bag. By doing so, the weight increases and the function as a sandbag improves.

Further, the method for producing a water-absorbent body according to the present invention is a method for producing a water-absorbent body comprising a water-permeable bag-like body containing a powdery, granular or other small piece of water-absorbent polymer. Then, a small polymer material containing acrylonitrile and styrene and / or conjugated diene is subjected to an acid treatment to obtain a water-absorbing polymer that is a modified polymer that absorbs water and exhibits a gel state. In addition to encapsulating the flaky water-absorbing polymer in the water-permeable bag, a surfactant is contained in at least one of the water-absorbing polymer and the water-permeable bag before the encapsulation step. Therefore, the water absorbing body having the above advantages can be provided in a simple process at a low cost.

In the method for producing a water-absorbent body of the present invention, since the polymer material contains carbon black or titanium oxide to promote the acid treatment of the polymer material, the water-absorbent polymer can be produced in a short time. Thus, the water absorbent can be provided at a lower cost.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing a structure of a water absorbing body according to a first embodiment of the present invention, wherein (a) shows a state before water absorption and (b) shows a state after water absorption. Things.

FIG. 2 is a schematic cross-sectional view showing a structure of a water absorbing body according to a second embodiment of the present invention, wherein (a) shows a state before water absorption and (b) shows a state after water absorption. Things.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Water absorption body, 2 ... Water-permeable bag-like body, 3 ... Water absorption material,
3a: water-absorbing material before water absorption, 3b: water-absorbing material after water absorption, 4: solid matter, 11: water absorbing body

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08K 3/22 C08K 3/22 C08L 33/20 C08L 33/20 E02B 3/04 301 E02B 3/04 301 F Terms (reference) 2D018 AA06 4F073 AA01 BA18 BA19 BA20 BB05 EA11 EA19 EA23 EA32 EA33 EA35 4F100 AA21A AA21H AA37A AA37H AB01 AD00 AG00 AK12A AK12J AK27A AK27J AK28A18 BA18 BA18 BAK AK28 BAK DG13 DG15 EH312 EJ01A GB90 JA13A JD05B JD05C JD15 JD15A JL05 JL16 JL16A JM10A YY00A YY00B YY00C 4J002 AC071 BC061 BN101 BN151 CH052 DA036 DE136 EN027 EN137 EV187 EV257 EW0317 FD037

Claims (17)

[Claims] 1. A water-absorbent body comprising a water-permeable bag-like body containing a powdery, granular or other small-piece-like water-absorbent polymer, wherein the water-absorbent polymer is acrylonitrile, styrene and / or A modified polymer obtained by subjecting a polymer material containing a conjugated diene to an acid treatment and exhibiting a gel state by water absorption,
A water-absorbing body, wherein at least one of the water-permeable bag-like body and the water-absorbing polymer contains a surfactant. 2. The water-permeable bag-like body containing the water-absorbing polymer and small solids such as powder or granules having a specific gravity of 1 or more. Water absorber. 3. The water absorbent according to claim 1, wherein the surfactant is an anionic surfactant and / or a nonionic surfactant. 4. The content of the surfactant with respect to 100 parts by weight of the water-absorbing polymer in a dry state and the content of the surfactant with respect to 100 parts by weight of a water-permeable bag in a dry state are both 0.01% by weight. The water absorber according to claim 1, wherein the amount is not less than 10 parts by weight and not more than 10 parts by weight. 5. The content of the surfactant per 100 parts by weight of the water-absorbing polymer in a dry state and the content of the surfactant per 100 parts by weight of a water-permeable bag in a dry state are both 0.1% by weight. The water absorber according to claim 1, wherein the amount is not less than 5 parts by weight and not more than 5 parts by weight. 6. The water absorber according to claim 1, wherein the polymer material contains acrylonitrile units in an amount of 5 mol% or more and 80 mol% or less. 7. The water absorbent according to claim 1, wherein the polymer material contains acrylonitrile units in an amount of 10 mol% or more and 60 mol% or less. 8. The water absorber according to claim 1, wherein the polymer material contains acrylonitrile units in an amount of 20 mol% or more and 50 mol% or less. 9. The water absorber according to claim 1, wherein the polymer material contains styrene and / or a conjugated diene unit in an amount of 20 mol% or more and 95 mol% or less. 10. The polymer material according to claim 7, wherein the styrene and / or
Or the conjugated diene unit is contained in an amount of 40 mol% or more and 85 mol% or less. 11. The polymer material according to claim 11, wherein the styrene and / or
3. The water absorbent according to claim 1, comprising a conjugated diene unit in an amount of 50 mol% or more and 80 mol% or less. 4. 12. The method according to claim 1, wherein the polymer material contains carbon black or titanium oxide.
Or the water absorber according to 2. 13. The water-absorbent material according to claim 1, wherein the water-absorbent polymer is a waste polymer material containing acrylonitrile and styrene and / or conjugated diene as a starting material. 14. A method for producing a water-absorbent body comprising a water-permeable bag-like body containing a powdery, granular or other small-piece-like water-absorbent polymer, comprising acrylonitrile, styrene and / or conjugated diene. By treating the flake-shaped polymer material containing the water-absorbing polymer, which is a modified polymer that absorbs water and exhibits a gel state, the flake-shaped water-absorbing polymer is subjected to water permeability. A method for producing a water-absorbent body, wherein the water-absorbent body and at least one of the water-permeable bag-like bodies contain a surfactant before the enclosing step. 15. The water-permeable bag-like body, wherein the small-piece water-absorbing polymer and a small-piece solid such as powder or granule having a specific gravity of 1 or more are sealed. The method for producing a water absorbent according to the above. 16. The method for producing a water absorbent according to claim 14, wherein the small-sized polymer material contains carbon black or titanium oxide. 17. The method according to claim 14, wherein the flake-shaped water-absorbing polymer is a starting polymer material of waste material containing acrylonitrile and styrene and / or conjugated diene. A method for producing a water absorbing body.