JPS61263639A - Improved steam-absorbing and-desorbing agent - Google Patents

Abstract

PURPOSE:To control moisture absorption over a wide range by integrating a polymer, obtained by insolubilizing the homopolymer or copolymer of methacrylamide shown by a specified general formula in water, with a hygroscopic org. compd. CONSTITUTION:The homopolymer or copolymer of N-alkyl or N-alkylene- substituted methacrylamide shown by formula I (R1 is H and methyl, R2 is H, methyl and ethyl and R3 shows methyl, ethyl and propyl) or formula II [R1 is H and methyl and A shows -(CH2)n wherein (n) is 4-6 and -(CH2)2- O-(CH2)2-] or the copolymer with other copolymerizable monomers is insolubilized in water. The obtained polymer is integrated with a hydroscopic org. compd. by kneading, etc., to form a steam-absorbing and -desorbing agent. A polyhydric alcohol compd. is preferably used as the hygroscopic org. compd.

Description

[Detailed description of the invention] The present invention relates to improved water vapor absorption and release agents.

More specifically, the present invention relates to an improved water vapor absorption/release agent formed by integrating a water-insoluble polymer of a specified (meth)acrylamide derivative with a hygroscopic organic compound.

Conventional technology and its problems Traditionally, humidity control methods for regulating the temperature in gases have mainly been performed by operating separate devices that have two functions: dehumidification and humidification, and are less effective than temperature control. Extremely complicated equipment and operations are required.

Therefore, problems such as condensation that occur due to changes in room temperature have not been fundamentally solved in closed spaces such as greenhouses, greenhouses, and pillboxes where there is little inflow of outside air. This has become a problem in a variety of ways, including the occurrence of electronic equipment such as computers and other electronic equipment in offices within buildings.

On the other hand, in crop cultivation in dry areas or soils with poor water retention, humidification in the soil becomes a problem, and various humidification agents such as soil water retention agents are being investigated.

Recently, in order to solve the above-mentioned problems, there has been an idea to use hydrophilic resins with water absorption ability for humidity control, in addition to the conventional idea of air conditioning.

Various prototypes are being considered.

The present inventors conducted studies for the above-mentioned purpose.

We have discovered that a polymer obtained by making a specified (meth)acrylamide derivative polymer, which is also applied to the present invention, insolubilized in water is suitable as a water vapor absorbing and releasing agent.
We have already proposed its use.

Specifically, the nucleating agent has extremely advantageous properties as a water vapor absorbing and releasing agent: it absorbs water vapor well in low temperature/high humidity conditions, and releases water vapor in high temperature/low humidity conditions. However, one drawback is that it absorbs only a small amount of moisture, which may be a problem if used in a relatively narrow space or in applications where low humidity conditions are not strongly required. This means that it will not be able to fully demonstrate its function in certain applications.

Means for Solving the Problems: The present inventors conducted extensive studies in view of the above-mentioned problems, and found that a polymer made by making a polymer of a specified (meth)acrylamide derivative insoluble in water and a hygroscopic organic compound They discovered that by integrating the two, the amount of moisture absorbed increases significantly, and surprisingly, there is little decrease in moisture release ability, and a large amount of water vapor can be absorbed and released, leading to the present invention.

That is, one aspect of the present invention is represented by the general formula (I) or (II) (in the above formula, the crest is a hydrogen atom or a methyl group, the horse is a hydrogen atom, a methyl group or an ethyl group, and RG is a methyl group.

It is an ethyl group or a propyl group. ) (In the above formula, the mountain is a hydrogen atom or a methyl group, A is +CHz+
. and n is 4 to 6 or CH2+20+cH2+2. ) A polymer made by insoluble in water a homopolymer or a copolymer of N-alkyl or N-alkylene substituted (meth)acrylamide, or a copolymer with other copolymerizable monomers, and a hygroscopic organic compound. This is an improved water vapor absorbing/releasing agent.

Examples of monomers used in the present invention include N-n
-Propylacrylamide, N-n-propylmethacrylamide, N-inopropylacrylamide, N-isopropylmethacrylamide.

N-ethylacrylamide, N,N-diethylacrylamide, N-ethylmethacrylamide.

Examples include N,N-dimethylacrylamide, N,N-dimethylmethacrylamide, N-acryloylpyrrolidine, N-methacryloylpyrrolidine, N-acryloylpiperidine, N-methacryloylpiperidine, and N-acryloylmorpholine.

In addition, monomers that can be copolymerized with the above monomers include:
Examples include hydrophilic monomers, ionic monomers, lipophilic monomers, etc., and one or more of these monomers can be applied, but among them, use of hydrophilic monomers and ionic monomers is preferred.

Specifically, examples of the hydrophilic monomer include acrylamide, methacrylamide, N-methylacrylamide,
Diacetone acrylamide, hydroxyethyl methacrylate, hydroquine ethyl acrylate, hydroxypropyl methacrylate, hydroxypropyl acrylate, various metquin polyethylene glycol methacrylates, various methoxy polyethylene glycol acrylates), N-vinyl-2-pyrrolidone, etc. It is also possible to introduce vinyl acetate, grindyl methacrylate, etc. by copolymerization and hydrolyze it to impart hydrophilicity.As the ionic monomer,
For example, acrylic acid, methacrylic acid, vinylsulfonic acid, allylsulfonic acid, methallylsulfonic acid, styrenesulfonic acid.

Acids such as 2-acrylamido-2-phenylpropanesulfonic acid and 2-acrylamido-2-methyl-propanesulfonic acid and their salts, N,N-dimethylaminoethyl methacrylate), N,N-diethylaminoethyl methacrylate, Examples include amines and salts thereof such as N,N-dimethylaminoethyl acrylate, N,N-dimethylaminopropylmethacrylamide, and N,N-dimethylaminopropylacrylamide.

Various acrylates, methacrylates, acrylamides,
It is also possible to introduce methacrylamide, acrylonitrile, etc. by copolymerization and hydrolyze it to impart ionicity.

Examples of the lipophilic monomer include N-n-butylacrylamide, N-tert,-butylacrylamide,
N-alkyl (meth)acrylamide derivatives such as N-n-hexyl acrylamide and N-n-octyl methacrylamide, (meth)acrylate derivatives such as ethyl acrylate, methyl methacrylate, and butyl acrylate, acrylonitrile, methacrylonitrile, vinyl acetate, Examples include styrene, α-methylstyrene, phtadiene, isoprene, and the like.

Methods for making the monomer polymers mentioned above insolubilized in water include a method of making them insolubilized during one polymerization and a method of making them insolubilized by a treatment after polymerization. A method of copolymerizing a crosslinkable monomer having a double bond with the above-described (meth)acrylamide derivative, a method of copolymerizing an N-alkoxymethyl (meth)acrylamide derivative, a method of copolymerizing the above-mentioned lipophilic monomer with (meth)acrylamide derivative,
A method of copolymerizing an acrylamide derivative, 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, etc. can be adopted.

More specifically, in the first method, as a crosslinking monomer,
For example, N,N'-methylenebisacrylamide,
N,N-diallylacrylamide, triacryl formal, N,N-diacrylolimide, ethylene glycol acrylate, ethylene glycol dimethacrylate, propylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4-butylene glycol dimethacrylate , glycerol dimethacrylate, neopentyl glycol dimethacrylate.

Trimethylolpropane triacrylate, divinylbenzene, diallyl phthalate, etc. can be used.

The N-alkoxymethyl (meth)acrylamide derivatives in the second method also include N-hydroxymethyl (meth)acrylamide, such as N-methylol (meth)acrylamide.
Acrylamide, N-methoxymethyl (meth)acrylamide, N-ethoxymethyl (meth)acrylamide,
N-n-butoxymethyl (meth)acrylamide, N
-tert, -butoxymethyl(meth)acrylamide, etc. can be used.

The ratio of the lipophilic monomer to the (meth)acrylamide derivative having unsafe properties in the third method varies depending on the combination of the (meth)acrylamide derivative and the lipophilic monomer; 1 or more, preferably 3 or more.

The fourth method is bulk polymerization.

A method can be employed in which the polymer is directly polymerized without being diluted with a solvent to obtain a polymer block, or a method in which the polymer is suspended in a solvent and then polymerized in a monomer cylinder to obtain a 6-particulate polymer.

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

The sixth method of integrating with fibrous materials is cellulose, nylon, polyester.

Water-insoluble fibrous materials such as acrylic fibers, nonwoven fabrics made of polypropylene, ethylene-propylene copolymers, etc., or silica, alumina.

A method of impregnating or graft polymerizing the above-mentioned (meth)acrylamide derivative into a water-insoluble porous inorganic substance such as zeolite, a method of impregnating a water-insoluble inorganic substance with a polymer, etc. can be employed.

Each of the six methods described above may be used alone or in combination. In general, more effective results can be obtained when used together.

More specific polymerization methods that can be adopted in producing the water vapor absorbing and releasing agent of the present invention according to the above-mentioned method include, for example, (1) polymerizing the monomer as it is without diluting it with a solvent to form a polymer block; (2) A method of polymerizing in a solvent and drying after polymerization or precipitating the polymer in a poor solvent to obtain a single polymer; (3) A method of obtaining a particulate polymer by suspension polymerization; (4) ) A method of obtaining a polymer latex by emulsion polymerization, (5) A method of integrating a polymer by impregnating a water-insoluble fibrous substance or a porous inorganic substance with a polymer solution or graft polymerization, etc. be able to. In addition, in the above manufacturing process,
It is also possible to produce a polymer in which the fibrous material is dispersed by adding fibrous material chopped into pieces of 10 mm or less and performing polymerization or subsequent treatment.

At this time, the polymerization can be initiated by heating alone, but better results are usually obtained by using a polymerization initiator.

The polymerization initiator is not limited as long as it has the ability to initiate radical polymerization, and includes, for example, inorganic peroxides, organic peroxides, combinations of these peroxides and reducing agents, and azo compounds. Specifically, ammonium persulfate, potassium persulfate, hydrogen peroxide, tert-butyl peroxide, benzoyl peroxide, and cumene hydroquine peroxide.

Examples include tert-butylperoxy-2-ethylhexanoate, butyl perbenzoate, and reducing agents used in combination with these include sulfites, hydrogen sulfites, and iron.

Examples include salts with low ionic valences such as copper and cobalt, organic amines such as aniline, and reducing sugars such as aldose and ketose. Examples of the azo compound include azobisisobutyronitrile, 2,2-azobis-2-amidinopropane hydrochloride, 2,2'-azobis-2,4-dimethylvaleronitrile, 4,4'-7zopisu-4-cyazubarein. Acids etc. can be used. It is also possible to use two or more of the above polymerization initiators in combination. In this case, the addition amount of the polymerization initiator is sufficient to be within the normally adopted quantitative range, for example, 0.01 to 5% by weight per monomer,
Preferably it is in the range of 0.05 to 2% by weight.

Among the polymers obtained in this way, those in block form or those obtained by distilling off the solvent are crushed into powder or melted into granules.

Formed into flakes, fibers or films.

Particulate polymers can be provided in neat form, and latex-like polymers can be impregnated and coated on fibrous materials such as cloth and paper, or as films.

On the other hand, the hygroscopic organic compound is not particularly limited as long as it has hygroscopic properties, and may be either water-soluble or water-insoluble.

Specifically, hydroxyl-substituted compounds, carboxylic acids, sulfonic acids or salts thereof, primary.

Examples include secondary and tertiary amines or their salts, as well as quaternary ammonium salts, among which hydroxyl-substituted compounds, especially polyhydric alcohol compounds, have excellent compatibility with the polymer to be integrated. preferable.

Examples of polyhydric alcohol compounds include dihydric, trihydric, and tetrahydric alcohols, their polymers, and polyvinyl alcohol. There are two types of dihydric alcohols: ethylene glycol and its polymer, and propylene glycol and its polymer. As the polymer of ethylene glycol, a range from diethylene glycol (2) to high molecular weight polyethylene glycol having a molecular weight of several tens of degrees can be applied, but a low molecular weight one having a molecular weight of several thousand or less is preferable.

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

It may also be a copolymer of polyethylene glycol and polypropylene glycol. Examples of trihydric alcohols include glycerin and trimethylolpropane, and examples of tetrahydric alcohols include pestaerythritol. Further, the above-mentioned polyhydric alcohol polymer is a polymer obtained by dehydration condensation of trihydric and tetrahydric alcohols, and includes polyglycerin and the like. Furthermore, the above-mentioned compounds in which part of the hydroxyl group has become an ether group or an ester group may also be used. Those with low molecular weight are preferred.

The amount of these organic compounds added varies depending on the purpose of use and cannot be uniformly specified, but if the amount added is too small, the effect will not be clear, and if it is too large, the hygroscopic ability will increase, but this is a feature of the present invention. Since the moisture release ability is impaired, the content is generally 3 to 97% by weight in the composition of the agent.

Preferably it is 5 to 75% by weight. However, in any case, even with the addition of such a large amount of hygroscopic organic compounds,
It is a major feature of the present invention that the moisture desorption ability of the nucleating agent is little reduced, and it is thought that the absorbed moisture is exchanged between the hygroscopic organic compound and the nucleating agent. Next, there is a method of integrating these hygroscopic organic compounds into a polymer to produce a water vapor absorbing and moisture releasing agent.Method 1: After polymerization, these organic compounds are allowed to coexist during polymer production and are polymerized and integrated. There are a method of integrating an organic compound by kneading or the like, 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 of the nucleating agent depends on how the nucleating agent is used, so it cannot be uniformly defined.

However, in general, these polymers are often used in the form of powder or granules, or in the form of impregnation or coating on fibrous materials such as cloth or nonwoven fabric. The powdered product can be obtained by various methods such as gel polymerization in an aqueous solution as described above, followed by drying and pulverization. At that time,
Integration can be achieved by dissolving or dispersing the organic compound to be integrated into a polymerization solution and polymerizing it, or further integrating by impregnating or spraying an aqueous solution or dispersion of the organic compound to be integrated into a powdered product. .

On the other hand, granular products are generally easily produced by suspension polymerization, but since the acrylamide or methacrylamide derivatives used in the present invention are generally highly water-soluble, suspension polymerization is not suitable.

Reverse-phase suspension polymerization in which monomers or their aqueous solutions are dispersed in oil, salting-out suspension polymerization in which monomer solubility is suppressed by dissolving polyphagous electrolytes in the aqueous solution, and further A method such as precipitation suspension polymerization, in which polymerization is performed at a high temperature higher than the cloud point of the polymer to precipitate the polymer, is employed.

In the case of reversed-phase suspension polymerization, it is possible to integrate the organic compound by dissolving or dispersing it in an aqueous monomer solution and performing the polymerization, and in either case, the granular product can be impregnated or sprayed with an aqueous solution or dispersion of the organic compound. do it. In addition, when used in the form of impregnating or coating a fibrous material, the organic compound may be dissolved or dispersed in the aqueous solution for impregnation or coating, or the aqueous solution of the organic compound may be applied to the fibrous material after impregnation or coating. Alternatively, the dispersion may be impregnated or sprayed, but the former is more convenient since it requires only one step. In addition to fibrous materials, porous materials such as silica, alumina, and zeolite can also be used as coating materials.

The water vapor absorbing and releasing agent produced as described above is in a solid state, and when it comes into contact with gaseous water, such as moisture in the atmosphere, it absorbs and retains water, and depending on the humidity and temperature of the outside air, it absorbs and retains water.
Water can be absorbed and released, and the process can be repeated. Generally, the amount of moisture absorbed at low temperatures is greater than the amount of moisture absorbed at high temperatures, so it is possible to act as a dehumidifier at low temperatures and as a humidifier at high temperatures, reducing changes in relative humidity due to temperature changes, and It has the function of maintaining constant humidity.

The moisture absorption amount of the water vapor absorption and release agent varies depending on the polymer composition and temperature/humidity conditions, but is approximately 0.1 of its own weight.
It can absorb up to 5 times as much water vapor. In this case, the amount of moisture absorbed by the combination may be greater than the amount of moisture absorbed by each component alone, and a synergistic effect may be observed due to the combination.

Moisture-absorbed agents can be quickly released by placing them in a higher temperature environment or a lower humidity environment. In this way, moisture absorption and moisture release can be quickly 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 not found in conventional moisture absorbers.

When repeatedly using the water vapor absorbing and releasing agent of the present invention, the larger the amount of moisture absorption.

However, the amount of moisture remaining in the agent after moisture release increases.

The difference between the moisture content when moisture is absorbed and the moisture content when moisture is released is also large, so this does not pose a major problem when used repeatedly.

Therefore, since the water vapor absorbing/releasing agent of the present invention can easily control the amount of moisture absorbed, it is possible to control the humidity of a large volume of gas by the presence of the vesicular nucleating agent.

A specific method for controlling humidity using the water vapor absorbing/releasing agent of the present invention is to simply bring the nucleating agent into contact with the gas to be controlled.

There are no particular restrictions on the shape of the nucleating agent; it may be in powder form.

Depending on the purpose, particles, flakes, fibers, films, or composites thereof with other fiber materials can be used. As a specific method for compositing, a method can be adopted in which a nucleating agent is sandwiched between fiber materials such as cloth or nonwoven fabric, and the materials are integrated by heat fusion, adhesion, or the like. At this time, heating or dehumidification can be performed depending on the temperature and humidity of the atmosphere, and this can be repeated as many times as the atmosphere changes.

As a more specific water vapor absorption and release method (1)
There are two main methods: (1) a method in which a nucleating agent is placed in the atmosphere and the water vapor is absorbed and released by relying on the functions of the nucleating agent; and (2) a method in which water vapor is absorbed and released by controlling the temperature of the nucleating agent. Two methods can be adopted. powder, granular,
In the case of using a flaky nucleating agent, in method (1), a fixed bed or a fluidized bed is used.

The nucleating agent and the gas may be brought into contact using a moving bed or the like. In the method (2), the above-described method may be adopted so that the nucleating agent can be heated or cooled by external heat exchange, internal heat exchange, or the like.

On the other hand, in the case of fibers, films, or composites of nucleating agents with fiber materials or films, they may be adhered to walls like wallpaper, or hung indoors like awnings or curtains. In any case, it is sufficient as long as it can come into sufficient contact with the moisture in the gas. When method (2) is adopted in this manner, although it is not as simple as method (1), for example, the above-mentioned nucleating agent is processed into a tube shape and steam and water are placed inside the tube.

A method of heating and cooling by flowing temperature-controlled gas, etc.
Also, apply the above-mentioned nucleating agent to walls, curtains, awnings, etc.

When used as wallpaper, etc., a method of heating and cooling from the outside is adopted.

In addition, by appropriately selecting the composition and usage amount of the nucleating agent, it is possible to set the humidity in the gas to be high or low. When using a material with high moisture absorption, it can be set to a low humidity range.

Specific applications include humidity control during crop cultivation in closed spaces such as greenhouses, vinyl greenhouses, and greenhouse horticulture using vinyl film, and humidity in rooms where electronic equipment sensitive to high humidity such as computers is installed. Examples include regulating humidity, preventing dew condensation on walls and windows of ordinary houses, and regulating humidity within the soil.

Function: As described above, the water vapor absorbing/releasing agent of the present invention can control the moisture absorption amount over a wide range by first changing the amount of the organic compound to be integrated.

Water vapor absorption and release can be carried out for a variety of purposes. Second, it absorbs a large amount of moisture at low temperatures and releases a large amount of moisture at high temperatures, so it has a high humidity control function. Thirdly, since the amount of moisture absorbed varies greatly with temperature, the moisture content in the gas can be controlled over a wide range depending on temperature. Fourthly, the moisture-absorbed nucleating agent is less corrosive, so it has the advantage of being able to be used integrally with a metal plate such as a steel plate.

The present invention will be further explained below with reference to Examples.

Example I 507.5 g of N-acryloylpyrrolidine and N,N
'-2.6g of methylenebisacrylamide and 11g of distilled water
゛, dissolved in 170g, Q, 5wt N, N'-
An aqueous solution of N-acryloylpyrrolidine containing methylenebisacrylamide was prepared. After the aqueous solution was cooled to 10°C, it was transferred to a stainless steel Ziwer bottle No. 21, and
Nitrogen gas was bubbled through a ball filter at a flow rate of /min for 1 hour. Then, a solution prepared by dissolving 2259 ammonium persulfate in 10 parts distilled water and a solution prepared by dissolving 1.16 g of sodium bisulfite in 10 parts distilled water were added simultaneously to the aqueous solution.

The aqueous solution was polymerized adiabatically. The obtained gel was shredded and dried, and then further crushed to collect a fraction of 20 to 100 mesh pieces to prepare a sample powder. 2 g of glycerin-containing sample powder obtained by thoroughly mixing the sample powder with the same amount of glycerin was 15α×15c! Spray it evenly on the surface of a polyester non-woven fabric (weight 1.27 g) with a size rL, then layer the same non-woven fabric on top of it, and apply a
A sample of the nonwoven fabric with the glycerin-containing sample powder sandwiched therein was prepared by heat-sealing the upper and lower nonwoven fabrics in the shape of an IL-angled base. The sample was suspended in a constant temperature and humidity chamber adjusted to a temperature of 10°C and a relative humidity of 98°C, and the amount of moisture absorbed per 1g of sample was measured. After 1 hour, it was 0.2
19.0.29g after 2 hours, 0.35g after 3 hours,
0.39g after 4 hours and 0.719 after 10 hours
It was absorbing moisture. Next, this moisture-absorbed sample was suspended in a constant temperature and humidity chamber adjusted to a temperature of 40'C and a relative humidity of 40 degrees, and after one hour, sample 1
The moisture content per 2 hours was 0.149, meaning that 0.57 moisture was released per 1 g of sample, and 0.6 after 2 hours.
After 49.3 hours, 0.68 g of moisture had been released. Moisture absorption and moisture release were repeated 10 times using the sample.

Examples 2 to 7 If there is no change in the shape, appearance, moisture absorption, moisture release, etc. of the sample from before the test, apply the same amount of polyhydric alcohol shown in Table 1 as the sample powder obtained in Example 1. 2 g of polyhydric alcohol-containing sample powder obtained in the same manner as in Example 1 using
Using a sample of the nonwoven fabric sandwiched with the sample, the amount of moisture absorbed and released per sample 17 was measured in the same manner as in Example 1, and the results shown in Table 1 were obtained.

Comparative Example 1 Example 1 using 2 g of sample powder obtained in Example 1
Using a sample of nonwoven fabric sandwiching the sample powder obtained in the same manner as in Example 1, the moisture absorption and moisture release were determined in the same manner as in Example 1. The amount of moisture released was 0.41 g, and the amount of moisture released after 1 hour was 0.35 g.

Examples 8-9 Nylon fibers with a length of 1 flu and a thickness of 3 denier 76.
A sample powder was obtained in the same manner as in Example 1 except that 59 was added. Using one sample powder and one polyhydric alcohol listed in Table 2, using a nonwoven fabric sample sandwiching a polyhydric alcohol-containing sample powder obtained by the same method as in Example 1, The amount of moisture absorbed and released per gram of sample was measured in the same manner as in Example 1, and the results shown in Table 1-2 were obtained. Moisture absorption and
Although moisture release was repeated 10 times, there was no change in the shape, appearance, amount of moisture absorbed, amount of moisture released, etc. of the sample from before the test.

Example 10 The sample powder was prepared in the same manner as in Example 1, except that 10 grams of the diethylene glycol-containing sample powder obtained in Example 3 was spread on a 200-mesh stainless steel wire mesh and left standing in a constant temperature and humidity chamber. When the amount of moisture absorbed and released was measured, the amount of moisture absorbed per 12 sample powders was 1 after 10 hours.
．． It is 482.

The amount of moisture released after 1 hour was 1,429.

Example 11 100% N-acryloylpyrrolidine in 17009% distilled water
After adding 3 g of sodium 2-acrylamido-2-phenylpropanesulfonate and replacing the inside of one reactor with nitrogen, the reactor was heated to 60°C.

Then, 0.67 g of potassium persulfate was added to the reaction solution to initiate polymerization, and the polymerization was continued for 3 hours. As the polymerization progressed, the reaction solution gradually became cloudy and became emulsion black. Next, 50 g of acrylonitrile was added to the reaction solution using a pump.
Added over 0 minutes. After the addition is complete, the reaction solution is further diluted with
The reaction was carried out at 60°C for an hour. The obtained emulsion solution became an aqueous solution when the temperature decreased to 50°C or less. A solution of triethylene glycol dissolved in the polymer aqueous solution was added to
After coating both the front and back surfaces of a polypropylene-rayon nonwoven fabric (weight 1,339) with a size of CrIL x 15 CrIL.

A nonwoven sample coated with 0.39 polymer and 0.3 triethylene glycol was prepared by drying at 80° C. for 4 hours. Using this sample, the amount of moisture absorbed and released per gram of sample was measured in the same manner as in Example 1. The amount of moisture absorbed was 0.679 after 10 hours, and the amount of moisture released was 0.679. It was 65 ri.

Example 12 A sample powder containing polyethylene glycol was obtained by polymerization, shredding, drying, and pulverization in the same manner as in Example 1, except that 255 ml of polyethylene glycol having a molecular weight of 600 was added. Using 10 samples of the powder, the amount of moisture absorbed and released by the powder was measured in the same manner as in Example 10, and the amount of moisture absorbed per 12 sample powders was 1.1 after 10 hours.
6! ;! The amount of moisture released was 1.13 after 1 hour.

Example 13 50 g of a 10 wt % aqueous solution of propylene glycol was uniformly sprayed onto 5 samples of the powder obtained in Example 1 using a sprayer and absorbed. The sample powder was spread on a 200 mesh stainless steel wire mesh and left in a constant temperature and humidity chamber adjusted to a temperature of 40'C and a relative humidity of 40%, and after one hour, 44.5 g of It was releasing moisture. Next, this sample powder was left standing in a constant temperature and humidity chamber adjusted to a temperature of 10'C and a relative humidity of 98 degrees, and after 10 hours it had absorbed 1,339 moisture per gram of sample powder. .

Patent applicant Mitsui Toatsu Chemical Co., Ltd. Procedural amendment August 1st, 1986

Claims (2)

[Claims] (1) Expressed by the general formula (I) or (II) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (I) (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. , R_3 is a methyl group,
It is an ethyl group or a propyl group. )▲Mathematical formula, chemical formula,
There are tables, etc.▼(II) (In the above formula, R_1 is a hydrogen atom or a methyl group, and A is -(C
H_2)-_n, where n is 4 to 6 or -(CH_2)-_
2O-(CH_2)-. ) A polymer made by insoluble in water a homopolymer or a copolymer of N-alkyl or N-alkylene substituted (meth)acrylamide, or a copolymer with other copolymerizable monomers, and a hygroscopic organic compound. Improved water vapor absorption and release agent. (2) Improved water vapor absorption and absorption according to claim 1, wherein the hygroscopic organic compound is a polyhydric alcohol compound.
Release agent.