JPH0716603B2 - Improved water vapor absorbing / releasing agent - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improved water vapor absorber / release agent.

More specifically, it relates to an improved water vapor absorbing / releasing agent obtained by integrating a water-insoluble polymer of a specified (meth) acrylamide derivative with a hygroscopic organic compound.

Conventional technology and its problems Conventionally, the humidity control method for controlling the temperature in the gas is mainly performed by separately operating a device having two functions of dehumidification and humidification, which is different from the temperature control. Extremely troublesome equipment and work are required. Therefore, in enclosed spaces such as greenhouses, greenhouses, and buildings where the inflow of outside air is small, problems such as dew condensation that accompany changes in room temperature have not been fundamentally solved, and due to dew condensation in greenhouses. There are various problems such as the occurrence of diseases and the breakdown of electronic devices such as computers in offices in buildings. On the other hand, in the cultivation of crops in dry land or soil with poor water retention, humidification in the soil becomes a problem, and various humidifying agents such as soil water retention agents have been studied.

Recently, with respect to the above-mentioned problems, there is an idea of utilizing a hydrophilic resin having a water absorbing ability for humidity control, in addition to the conventional idea of air conditioning, and various trials have been made.

The present inventors have conducted studies for the above-mentioned purpose, and a polymer obtained by insolubilizing a polymer of the specified (meth) acrylamide derivative, which is also applied to the present invention, is a water vapor absorbing and releasing agent. It has been found to be suitable as, and has already proposed its use. Specifically, the agent has a very convenient property as an agent for absorbing and releasing water vapor, which absorbs water vapor well in a low temperature / high humidity state and releases water vapor in a high temperature / low humidity state. However, one drawback is that it has a small amount of moisture absorption, so it can be used without problems in a relatively narrow space or in applications where low humidity conditions are not strongly required, but use in a wide space or low humidity is an essential condition. Therefore, it will not be able to fully exhibit its function in applications such as.

Means for Solving the Problems: As a result of intensive investigations by the present inventors in view of the above problems, a polymer obtained by insolubilizing a specified polymer of a (meth) acrylamide derivative in water and a hygroscopic organic compound. As a result of the integration of the above, it was found that the moisture absorption amount greatly increases and, moreover, surprisingly, there is little decrease in the moisture releasing ability and a large amount of water vapor can be absorbed and released, and the present invention has been completed.

That is, the present invention is represented by the general formula (I) or (II) (In the above formula, R ₁ is a hydrogen atom or a methyl group, R ₂ is a hydrogen atom,
A methyl group or an ethyl group, and R ₃ is a methyl group, an ethyl group or a propyl group. ) (In the above formula, R ₁ is a hydrogen atom or a methyl group, A is CH _{2 n} and n is 4 to 6 or CH _{2 2} OCH _{2 2.} ) N-alkyl or N-alkylene-substituted (meth) acrylamide alone or It is an improved water vapor absorbing / releasing agent obtained by integrating a hygroscopic organic compound with a polymer obtained by insolubilizing a copolymer or a copolymer with another copolymerizable monomer in water.

Examples of the monomer used in the present invention include Nn-
Propyl acrylamide, N-n-propyl methacrylamide, N-isopropyl acrylamide, N-isopropyl methacrylamide, N-ethyl acrylamide,
N, N-diethylacrylamide, N-ethylmethacrylamide, N, N-dimethylacrylamide, N, N-dimethylmethacrylamide, N-acryloylpyrrolidine, N-
Methacryloyl pyrrolidine, N-acryloyl piperidine, N-methacryloyl piperidine, N-acryloyl morpholine etc. can be mentioned.

Further, as the monomer copolymerizable with the above-mentioned monomer,
Hydrophilic monomers, ionic monomers, lipophilic monomers, etc. can be mentioned, and one or more of them can be applied. Among them, hydrophilic monomers and ionic monomers are used. Is preferred.

Specifically, examples of the hydrophilic monomer include acrylamide, methacrylamide, N-methylacrylamide,
Examples include diacetone acrylamide, hydroxyethyl methacrylate, hydroxyethyl acrylate, hydroxypropyl methacrylate, hydroxypropyl acrylate, various methoxy polyethylene glycol methacrylates, various methoxy polyethylene glycol acrylates, and N-vinyl-2-pyrrolidone. , Vinyl acetate, glycidyl methacrylate, etc. may be introduced by copolymerization and hydrolyzed to impart hydrophilicity. Examples of the ionic monomer include acrylic acid, methacrylic acid, vinyl sulfonic acid,
Acids such as allylsulfonic acid, methallylsulfonic acid, styrenesulfonic acid, 2-acrylamido-2-phenylpropanesulfonic acid, 2-acrylamido-2-methyl-propanesulfonic acid and salts thereof, N, N-dimethylaminoethyl Amine such as methacrylate, N, N-diethylaminoethyl methacrylate, N, N-dimethylaminoethyl acrylate, N, N-dimethylaminopropyl methacrylamide, N, N-dimethylaminopropyl acrylamide, and salts thereof can be mentioned. . Also,
Various acrylates, methacrylates, acrylamides,
It is also possible to introduce methacrylamide, acrylonitrile or the like by copolymerization and hydrolyze it to impart ionicity.

Examples of the hydrophilic monomer include Nn-butylacrylamide, N-tert.-butylacrylamide and Nn.
-N-alkyl (meth) acrylamide derivatives such as hexyl acrylamide and N-n-octyl methacrylamide, (meth) acrylate derivatives such as ethyl acrylate, methyl methacrylate and butyl acrylate, acrylonitrile, methacrylonitrile, vinyl acetate, styrene, α -Methylstyrene, butadiene, isoprene and the like can be mentioned.

As a method of insolubilizing the above-mentioned monomer polymer in water, there are a method of insolubilizing at the time of polymerization and a method of insolubilizing by treatment after the polymerization, but as a specific insolubilizing method, at least two or more in the molecule. A method of copolymerizing a crosslinkable monomer having a double bond with the above-mentioned (meth) acrylamide derivative, a method of copolymerizing an N-alkoxymethyl (meth) acrylamide derivative, the above lipophilic monomer and a (meth) acrylamide derivative. A method of copolymerizing, a method of polymerizing in bulk, a method of heat-treating the polymer, a method of integrating the polymer with a water-insoluble fibrous substance such as cellulose, and the like can be adopted.

More specifically, in the first method, as the crosslinkable monomer,
For example, N, N'-methylenebisacrylamide, N, N'-
Diallyl acrylamide, triacrylic formal, N,
N-diacryloylimide, ethylene glycol acrylate, ethylene glycol dimethacrylate, propylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4-butylene glycol dimethacrylate, glycerol dimethacrylate, neopentyl glycol dimethacrylate, trimethylol Propane triacrylate, divinylbenzene, diallyl phthalate and the like can be used.

The N-alkoxymethyl (meth) acrylamide derivative in the second method also includes N-hydroxymethyl (meth) acrylamide, for example N-methylol (meth).
Acrylamide, N-methoxymethyl (meth) acrylamide, N-ethoxymethyl (meth) acrylamide,
N-n-butoxymethyl (meth) acrylamide, N-
tert.-Butoxymethyl (meth) acrylamide and the like can be used.

Although the ratio of the hydrophilic monomer to the (meth) acrylamide derivative having an amphiphilic property in the third method varies depending on the combination of the (meth) acrylamide derivative and the hydrophilic monomer, it cannot be generally determined, but in general, It is 1% or more, preferably 3% or more.

As a method of performing bulk polymerization according to the fourth method, a method of polymerizing as it is without diluting with a solvent to obtain a polymer block or polymerization in a monomer while suspended in a solvent,
A method of obtaining a particulate polymer can be adopted.

In the method of heat-treating the polymer which is the fifth method, the heating conditions vary depending on the polymer and are not uniform, but generally, at a temperature of 60 to 250 ° C., preferably 80 to 200 ° C., bulk polymerization, The polymer obtained by suspension polymerization, solution polymerization or the like is heat-treated. At that time, in the solution polymerization, the drying or the distillation of the solvent may be combined with the heat treatment.

The sixth method is a method of integrating with a fibrous substance or the like, as a fiber such as cellulose, nylon, polyester, acrylic or a non-woven fabric made of polypropylene, ethylene-propylene copolymer or the like, which is insoluble in water. A method of impregnating or graft polymerizing the above-mentioned (meth) acrylamide derivative with a substance or a water-insoluble porous inorganic substance such as silica, alumina, or zeolite, and a method of impregnating a polymer can be adopted.

The above six methods may be adopted individually or in combination. More effective results can be obtained when used in combination.

As a more specific method of polymerization which can be adopted in producing the water vapor absorbing / releasing agent of the present invention according to the above-mentioned method, for example, (1) a monomer is directly polymerized without diluting with a solvent Method for manufacturing united block, (2)
Polymerization by polymerization in a solvent followed by drying or precipitation of the polymer in a poor solvent to obtain a polymer, (3) method of obtaining a particulate polymer by suspension polymerization, (4) polymer latex by emulsion polymerization And (5) a method of integrating a polymer with a water-insoluble fibrous substance or porous inorganic substance by a method such as impregnation of a polymer solution or graft polymerization. Further, in the above-mentioned production process, a fibrous substance shredded to 10 mm or less may be added to carry out polymerization or subsequent treatment to produce a polymer in which the fibrous substance is dispersed.

At that time, as a method for initiating the polymerization, heating may be used alone, but normally, a better result is obtained by using a polymerization initiator.

The polymerization initiator is not limited as long as it has the ability to initiate radical polymerization, and examples thereof include inorganic peroxides, organic peroxides, combinations of these peroxides with reducing agents, and azo compounds. Specifically, ammonium persulfate, potassium persulfate, hydrogen peroxide, tert-butylperoxide, benzoyl peroxide, cumene hydroxyperoxide, tert-butylperoxy-2-ethylhexanoate, butyl perbenzoate, etc. The reducing agents to be combined with these include sulfites, bisulfites, salts of low ionic value such as iron, copper and cobalt, organic amines such as aniline, and reducing sugars such as aldose and ketose. be able to. As the azo compound, azobisisobutyronitrile, 2,2'-azobis-2-amidinopropane hydrochloride, 2,2'-azobis-2,4-dimethylvaleronitrile,
4,4'-azobis-4-cyanovaleic acid or the like can be used. It is also possible to use two or more of the above-mentioned polymerization initiators in combination. In this case, the addition amount of the polymerization initiator is sufficient in a generally employed quantitative range, for example, 0.01 to 5 polymerization%, preferably 0.05 to 2 polymerization% per monomer.

Among the polymers obtained in this manner, a block-shaped one, or a polymer obtained by distilling off the solvent, is pulverized into a powder, or melted into a granule, a flake, a fiber or a film. The molded polymer can be provided in the form of the particulate polymer as it is, and the latex polymer can be provided by impregnating and coating with a fibrous substance such as cloth and paper, or by providing a film.

On the other hand, the hygroscopic organic compound is not particularly limited as long as it has hygroscopicity, and may be water-soluble or water-insoluble.
Specific examples thereof include hydroxyl-substituted compounds, carboxylic acids, sulfonic acids or their salts, primary, secondary and tertiary amines or their salts, and further quaternary ammonium salts. Among them, hydroxyl-substituted compounds In particular, the polyhydric alcohol compound is preferable because it has excellent compatibility with the polymer to be integrated.

Examples of the polyhydric alcohol compound include dihydric, trihydric, and tetrahydric alcohols and their multimers, and polyvinyl alcohol. The dihydric alcohol includes ethylene glycol and its polymer and propylene glycol and its polymer. As a polymer of ethylene glycol, diethylene glycol as a dimer to high molecular weight polyethylene glycol having a molecular weight of several hundred thousand is applicable, but a low molecular weight polymer having a molecular weight of several thousand or less is preferable.

The same applies to propylene glycol, with propylene glycol and its low molecular weight polypropylene glycol being preferred.

It may also be a copolymer of polyethylene glycol and polypropylene glycol. Trihydric alcohols include glycerin and trimethylolpropane, and tetrahydric alcohols include pentaerythritol. The above-mentioned multimer of polyhydric alcohol is a polymer obtained by dehydration condensation of trihydric and tetrahydric alcohols, such as polyglycerin. Further, in the above compounds, one part of the hydroxyl group may be an ether group or an ester group.

Hydrocarbons such as monosaccharides and polysaccharides may be mentioned as the hydroxyl group-substituted compounds other than the above-mentioned polyhydric alcohol compounds. Specific examples thereof include glucose, fructose, mannitol, maltose, lactose, raffinose, sucrose, dextran, cycloamylose and the like.

Although there are various polyvinyl alcohols having different degrees of hydrolysis and molecular weight, those having a low molecular weight which are close to complete hydrolysis are preferred in the present invention. The addition amount of these organic compounds varies depending on the purpose of use and cannot be uniformly defined. However, if the addition amount is small, the effect is not clear, and conversely if the addition amount is too large, the hygroscopic capacity increases, which is a feature of the present invention. Since the moisture releasing ability is impaired, it is generally 3 to 97% by weight, preferably 5 to 75% by weight in the composition of the agent. However, it is a major feature of the present invention that even if such a large amount of hygroscopic organic compound is added, the hygroscopic ability of the agent is less likely to decrease. It is considered that the water absorbed between the two is being exchanged.
Next, there is a method for producing a water vapor absorbing and desorbing agent by integrating these hygroscopic organic compounds into a polymer. When the polymer is produced, a method in which these organic compounds are allowed to coexist to polymerize and integrate, after polymerization, There are a method of integrating an organic compound by kneading, a method of integrally molding a polymer and an organic compound, and the like. More specifically, the method of integration is also related to the shape of the polymer. The shape cannot be uniformly defined because the shape of the agent depends on how the agent is used. However, in general, those polymers are often used in the form of powder or granules, or in the form of being impregnated or coated with a fibrous substance such as cloth or nonwoven fabric. As described above, the powdered product may be subjected to gel polymerization in an aqueous solution and then dried and pulverized to obtain various methods. At that time, it can be integrated by dissolving or dispersing the organic compound to be integrated in the polymerization liquid and polymerizing,
Furthermore, the powdery product can be integrated by impregnating or spraying with an aqueous solution or dispersion of an organic compound to be integrated.

On the other hand, a powdered product is generally easily produced by a suspension polymerization method, but since the acrylamide or methacrylamide derivative used in the present invention is generally highly water-soluble, the suspension polymerization method is Reverse phase suspension polymerization in which a monomer or an aqueous solution thereof is dispersed in oil, salting out suspension polymerization in which a large amount of an electrolyte or the like is dissolved in an aqueous solution to suppress the solubility of the monomer, and further a polymer A method such as precipitation suspension polymerization, in which the polymer is precipitated by performing the polymerization at a temperature higher than the cloud point, is adopted. In the case of reverse phase suspension polymerization, it can be integrated by dissolving or dispersing an organic compound in an aqueous monomer solution, and in any case, a powdery product is impregnated with an aqueous solution or dispersion of an organic compound or Just spray it. When the fibrous substance is used in the form of being impregnated or coated, the organic compound may be dissolved or dispersed in the aqueous solution to be impregnated or coated, or the fibrous substance after impregnated or coated is an aqueous solution of the organic compound. Alternatively, the dispersion may be impregnated or sprayed, but the former is more convenient because it requires only one step. In addition to fibrous substances, silica, alumina,
Porous materials such as zeolites can also be used.

The water vapor absorbing and releasing agent produced as described above is in a solid state, and absorbs and holds water by contact with gaseous water, for example, moisture in the atmosphere, and by the humidity and temperature of the outside air,
Water can be absorbed and released and this process can be repeated. In general, the amount of moisture absorbed at low temperatures is greater than that at high temperatures, so it can be used as a dehumidifier at low temperatures while acting as a humidifier at high temperatures, reducing changes in relative humidity due to temperature changes, and It has the function of keeping the humidity constant. The amount of water vapor absorbed and the amount of moisture absorbed by the release agent vary depending on the polymer composition and temperature / humidity conditions, but the amount of water vapor absorbed is approximately 0.1 times to 5 times the weight of its own weight. In that case, the moisture absorption amount of the integrated product may be larger than the moisture absorption amount of each of them alone, and a synergistic effect may be recognized by the integration.

It is possible to quickly release the moisture by placing the hygroscopic agent in an environment having a higher temperature or an environment having a lower humidity. As described above, the moisture absorption and the moisture release can be promptly performed by changing the surrounding environmental conditions. In particular, one of the features of the present invention is that the moisture release rate can be set to be equal to or higher than the moisture absorption rate, which is a property that conventional moisture absorbents do not have.

In the repeated use of the agent for absorbing and releasing water vapor of the present invention, the larger the amount of moisture absorption, the greater the amount of water remaining in the agent after moisture release. Since the difference with the water content when wet becomes large at the same time, it is not a big problem in repeated use.

Therefore, since the water vapor absorbing / releasing agent of the present invention can easily control the amount of moisture absorption, it is possible to regulate the humidity of a large volume of gas in the presence of a small amount of the agent.

As a specific method for controlling the humidity using the water vapor absorbing / releasing agent of the present invention, it is sufficient to bring the agent into contact with the gas to be humidity controlled.

The shape of the agent is not particularly limited, and powdery, powdery, flake-like, fibrous, film-like, or a combination thereof with other fiber materials can be used according to the application. As a concrete method of compounding, a method of sandwiching the agent with a fiber material such as a cloth or a non-woven fabric and integrating them by heat fusion, adhesion or the like can be adopted. At that time, it can be heated or dehumidified by the temperature and humidity of the atmosphere, and can be repeated as many times as the atmosphere changes.

As a more specific method for absorbing and releasing water vapor (1)
Mainly, a method of installing the agent in an atmosphere and absorbing and releasing water vapor depending on the function of the agent, and (2) a method of absorbing and releasing water vapor by controlling the temperature of the agent. Two methods can be adopted. Powder, powder,
In the case of using the flake-like agent, in the method (1), the agent and the gas may be brought into contact with each other in a fixed bed, a fluidized bed, a moving bed or the like. In the method (2), the above-mentioned manner may be adopted so that the agent can be heated or cooled by a method such as external heat exchange or internal heat exchange.
On the other hand, in a fibrous form, a film form or a composite of the agent with a fibrous material, a film or the like, it may be adhered to a wall like a wallpaper, or may be hung in a room like an awning or a curtain, In any case, it is sufficient if it is possible to make sufficient contact with the moisture in the gas. When the method of (2) is adopted in this manner, it is not as easy as the method of (1), but for example, the above-mentioned agent is processed into a tube and steam, water and temperature are adjusted therein. A method of heating and cooling by flowing gas or the like, or a method of heating or cooling from the outside when the above-mentioned agent is used as a curtain, awning, wallpaper or the like on a wall or the like is adopted.

Also, by appropriately selecting the composition and amount of the agent, it is possible to set the humidity in the gas to be higher or lower, and when a low moisture absorption amount is used, it can be set in a high humidity range. It can be set to a low humidity range when using a material with a high moisture absorption.

Specific applications include greenhouses, greenhouses, humidity control during cultivation of crops in enclosed spaces such as greenhouse horticulture using vinyl film, humidity control in rooms with computers and other electronic devices that are sensitive to high humidity, and general housing. It is possible to prevent dew condensation on walls and windows, and to control humidity in the soil.

Action: As described above, the water vapor absorbing / releasing agent of the present invention can control the moisture absorption amount in a wide range by changing the addition amount of the organic compound to be integrated first. It can absorb and release. Secondly, since it has a large amount of moisture absorption at low temperature and a large amount of release at high temperature, it has a high humidity control function. Thirdly, since the amount of moisture absorption changes greatly with temperature, it is possible to control the water content in the gas in a wide range depending on the temperature. Fourthly, since the agent that has absorbed moisture has low corrosiveness, it has an effect that it can be used integrally with a metal plate such as a steel plate.

The present invention will be further described below with reference to examples.

Example 1 N-acryloylpyrrolidine (507.5 g) and N, N'-methylenebisacrylamide (2.6 g) were dissolved in distilled water (1,170 g).
N-containing 5 wt% N, N'-methylenebisacrylamide
An aqueous solution of acryloylpyrrolidine was prepared. After cooling the aqueous solution to 10 ° C., it was transferred to a 2 l stainless steel dewar and nitrogen gas was bubbled through the pole filter at a flow rate of 1 / min for 1 hour. Then, a solution prepared by dissolving 225 g of ammonium persulfate in 10 g of distilled water and a solution prepared by dissolving 1.16 g of sodium hydrogen sulfite in 10 g of distilled water were simultaneously added to the aqueous solution to polymerize the aqueous solution adiabatically. The obtained gel was chopped and dried, and then further pulverized to collect a 20 to 100 mesh fraction, which was used as a sample powder. 2 g of glycerin-containing sample powder obtained by thoroughly mixing the sample powder with the same amount of glycerin was evenly dispersed on the surface of a polyester non-woven fabric (weight 1.27 g) having a size of 15 cm × 15 cm, and further The same non-woven fabric was superposed on the above, and the upper and lower non-woven fabrics were heat-sealed in a 1.5 cm square grid pattern to prepare a non-woven fabric sample in which the glycerin-containing sample powder was sandwiched.
The sample was hung in a thermo-hygrostat adjusted to a temperature of 10 ° C. and a relative humidity of 98%, and the amount of moisture absorption per 1 g of the sample was measured, which was 0.21 g after 1 hour, 0.29 g after 2 hours, and 3 hours. It had absorbed 0.35 g later, 0.39 g after 4 hours and 0.71 g after 10 hours. Then, this sample that has absorbed moisture,
When suspended in a thermo-hygrostat adjusted to a temperature of 40 ° C and a relative humidity of 40%, the amount of water per 1 g of sample was 0.14 g after 1 hour, and 0.57 g of water was released per 1 g of sample. The water content was 0.64 g after 2 hours and 0.68 g after 3 hours. Absorption and desorption of moisture using this sample
Repeated 10 times, there was no change in the sample shape, appearance, moisture absorption, moisture release, etc. from before the test.

Examples 2 to 7 Polyhydric alcohol-containing sample powder 2 g obtained by the same method as in Example 1 using the same amount of the polyhydric alcohol shown in Table 1 as the sample powder obtained in Example 1 Using a non-woven fabric sample sandwiched by, the moisture absorption amount and the moisture release amount per 1 g of the sample were measured in the same manner as in Example 1,
The results shown in Table-1 were obtained.

Comparative Example 1 Using a sample of nonwoven fabric in which 2 g of the sample powder obtained in Example 1 was sandwiched with the sample powder obtained in the same manner as in Example 1, the moisture absorption amount was obtained in the same manner as in Example 1. The moisture absorption amount per 1 g of the sample was 0.41 g after 10 hours, and the moisture release amount after 1 hour was calculated.
It was 0.35 g.

Examples 8 to 9 Sample powders were obtained in the same manner as in Example 1 except that 76.5 g of nylon fiber having a length of 1 mm and a thickness of 3 denier was added. Using the sample powder 1g and the polyhydric alcohol 1g described in Table 2 and using the sample of the non-woven fabric sandwiching the polyhydric alcohol-containing sample powder obtained by the same method as in Example 1, Sample in the same way as 1
The amount of moisture absorbed and the amount of moisture released per 1 g were measured, and the results shown in Table 2 were obtained. Moisture absorption and moisture release were repeated 10 times using the sample, but there was no change in the shape, appearance, moisture absorption amount, moisture release amount, etc. of the sample from before the test.

Example 10 10 g of the sample powder containing diethylene glycol obtained in Example 3 was sprayed on a 200-mesh stainless steel wire net,
When the moisture absorption amount and the moisture desorption amount of the sample powder were measured by the same method as in Example 1 except that the sample powder was allowed to stand in a thermo-hygrostat,
The moisture absorption amount per 1 g of the sample powder was 1.48 g after 10 hours, and the moisture release amount was 1.42 g after 1 hour.

Example 11 N-acryloylpyrrolidine (100 g) and 2 in distilled water (1700 g)
-Adding 3 g of sodium acrylamido-2-phenylpropanesulfonate and replacing the inside of the reactor with nitrogen,
Heated to 60 ° C. Then, 0.6 g of potassium persulfate was added to the reaction solution to start the polymerization, and the polymerization was carried out for 3 hours. As the polymerization proceeded, the reaction solution gradually became cloudy and became an emulsion. Then, 50 g of acrylonitrile was added to the reaction solution by using a pump over 30 minutes. After the addition was complete, the reaction was allowed to react for another 3 hours at 60 ° C. The obtained emulsion solution became an aqueous solution when the temperature fell below 50 ° C. A solution of triethylene glycol dissolved in the polymer aqueous solution
cm × 15 cm polypropylene-rayon non-woven fabric (weight 1.33 g) was applied to both front and back surfaces, and then dried at 80 ° C. for 4 hours to coat with 0.3 g of polymer and 0.3 g of triethylene glycol. A non-woven fabric sample was prepared. Using the sample, the amount of moisture absorption and the amount of moisture released per 1 g of the sample were measured by the same method as in Example 1. The amount of moisture absorption was 0.67 g after 10 hours, and the amount of moisture released was
It was 0.65 g.

Example 12 Polymerization, shredding, drying and pulverization were performed in the same manner as in Example 1 except that 255 g of polyethylene glycol having a molecular weight of 600 was added to obtain a polyethylene glycol-containing sample powder. Using 10 g of the powder, the amount of moisture absorption and the amount of moisture release of the powder were measured in the same manner as in Example 10. The amount of moisture absorption per 1 g of the sample powder was 1.16 g after 10 hours, and the amount of moisture release was also measured. Was 1.13 g after 1 hour.

Example 13 To 5 g of the sample powder obtained in Example 1, 50 g of a 10 wt% aqueous solution of propylene glycol was uniformly sprayed using a sprayer to absorb it. The sample powder was sprayed on a 200-mesh stainless steel wire net, and allowed to stand in a thermo-hygrostat adjusted to a temperature of 40 ° C. and a relative humidity of 40%. After 1 hour, 44.5 g of water was released. It was damp. Then, this sample powder was allowed to stand in a constant temperature and humidity chamber adjusted to a temperature of 10 ° C. and a relative humidity of 98%, and after 10 hours, 1 g of the sample powder
It had absorbed 1.33 g of water per unit.

Example 14 N-acryloylpyrrolidine (355.2 g), N, N'-methylenebisacrylamide (1.8 g), glucose (153.0 g) and water (1170 g)
To prepare an aqueous solution of N-acryloylpyrrolidine containing glucose. After cooling the water to 10 ° C, 2 l
The mixture was transferred to a stainless steel dewar bottle of No. 1 and nitrogen gas was bubbled for 1 hour using a ball filter at a flow rate of 1 / min. Next, 1.79 g of ammonium persulfate was added to the aqueous solution with 1 part of water.
A solution dissolved in 0 g and a solution prepared by dissolving 0.81 g of sodium hydrogen sulfite in 10 g of water were simultaneously added to polymerize the aqueous solution adiabatically. The obtained gel was chopped and dried, and then further pulverized to collect a 20 to 100 mesh fraction, which was used as a sample. 10 g
The sample powder of was sprayed on a stainless steel wire mesh of 200 mesh, and left for 10 hours in a constant temperature and humidity chamber adjusted to a temperature of 10 ° C. and a relative humidity of 98%, and the amount of moisture absorption per 1 g of the sample powder was measured, It was 0.49 g. Then, when the moisture-absorbed sample powder was left in a thermo-hygrostat adjusted to a temperature of 40 ° C. and a relative humidity of 40% for 1 hour, the water content per 1 g of the sample was 0.02 g, and 0.47 g of water was added. It was releasing moisture.

Examples 15 to 17 355.2 g of N-acryloylpyrrolidine and 1.8 g of N, N'-methylenebisacrylamide were dissolved in 1170 g of water, and 107.1 g of nylon fiber having a length of 1 mm and a thickness of 3 denier was suspended in the aqueous solution. Polymerization was carried out using ammonium persulfate and sodium hydrogen sulfite as a polymerization initiator in exactly the same manner as in Example 14, to obtain a polymer powder in exactly the same manner as in Example 14, and sieving to collect a fraction larger than 100 mesh. did.

2 g of PEG-containing sample powder obtained by thoroughly mixing the polymer powder with the same amount of polyethylene glycol having a molecular weight of 1000 (hereinafter abbreviated as PEG), the surface of a polyester non-woven fabric (weight 1.27 g) having a size of 15 cm × 15 cm A non-woven fabric sample in which the PEG-containing sample was sandwiched was prepared by uniformly sprinkling the same on the top, superposing the same non-woven fabric on it, and heat-bonding the upper and lower non-woven fabrics in a 1.5 cm square grid pattern. Using the sample, the moisture absorption amount per 1 g of the PEG-containing polymer after standing for 12 hours was measured successively under the temperature and humidity conditions shown in Table 3, and the results are shown in Table 3.

Claims (2)

[Claims] 1. Represented by the general formula (I) or (II) (In the above formula, R ₁ is a hydrogen atom or a methyl group, R ₂ is a hydrogen atom,
A methyl group or an ethyl group, and R ₃ is a methyl group, an ethyl group or a propyl group. ) (In the above formula, R ₁ is a hydrogen atom or a methyl group, A is CH _{2 n} and n is 4 to 6 or CH _{2 2} OCH _{2 2.} ) N-alkyl or N-alkylene-substituted (meth) acrylamide alone or An improved water vapor absorbing / releasing agent obtained by integrating a hygroscopic organic compound with a polymer obtained by insolubilizing a copolymer or a copolymer with another copolymerizable monomer in water. 2. The improved water vapor absorbing / releasing agent according to claim 1, wherein the hygroscopic organic compound is a polyhydric alcohol compound.