JP3538632B2 - Thermosensitive water release agent and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an aqueous solution at a temperature lower than a predetermined temperature, but at a higher temperature, it thickens, gels while maintaining its initial shape, and releases water. The present invention relates to a novel water release agent having a property of shrinking in size and solidifying, and a method for producing the same.

[0002]

2. Description of the Related Art In recent years, polymers and copolymers whose behavior with respect to water reversibly changes depending on temperature (hereinafter referred to as heat-sensitive polymer compounds exhibiting reversible low-temperature hydrophilicity-high-temperature hydrophobicity change) are one of the functional materials. Widely attracted attention as a species, for example, as an adsorbent for nonionic surfactants, a thermosensitive light-blocking agent, a thermosensitive thickener, a stain inhibitor, a marine antifouling material, an artificial muscle, a drug delivery system material, etc. The application development of has been studied.

[0003] As one kind of a heat-sensitive polymer material showing such a reversible low-temperature hydrophilicity-high-temperature hydrophobicity change, it is soluble in water at a predetermined temperature or lower, but becomes insoluble in water at a temperature higher than the predetermined temperature. An N-alkylamide polymer or copolymer exhibiting a reversible change in so-called heat-sensitive low-temperature water-solubility-high-temperature water-insolubility is known (JP-A-58-78758).

Also, an aqueous solution of a copolymer of N-isopropylacrylamide and another N-substituted acrylamide has a property of causing a phase transition based on a coil-globule transition, and separates into two phases at a transition temperature or higher. It is also known that a non-uniform distribution occurs in the concentration of the copolymer molecules and strong light scattering occurs to form a fine pattern [“Journal of Physical Chemistry (J. Phys. Chem.)”. 93, 331
1 page (1989), "Polymer Papers", 46th
Vol. 7, No. 4, pp. 437 (1989), Vol. 47, No. 6, pp. 467 (1990)].

[0005] By the way, when the gel is left, the phenomenon that water is naturally separated and the volume shrinks is called syneresis (Synthesis).
This is known as a phenomenon in which when yogurt is left for a long time, water precipitates on the upper surface or sweats on the surface of agar. The present inventors have found that certain N-alkylacrylamide-based polymers or copolymers exhibit such a syneresis phenomenon, and have proposed a heat-sensitive water releasing agent utilizing such a phenomenon (Japanese Patent Application Laid-Open No. 11-35641
Publication). However, it is necessary to use a cationic or anionic surfactant in the production of the heat-sensitive water-releasing agent, and there is a problem that after the completion of the reaction, this must be removed by a complicated treatment.

[0006]

The present invention 0005], although is an aqueous solution in less than a predetermined temperature, thickened at temperatures higher than, gate while maintaining the initial shape
Turned into Le, water dimensions shrinks while releasing, but solidified, has specific properties that it again becomes an aqueous solution when a lower temperature than, to provide a novel reversible thermosensitive syneresis agent It was made for the purpose.

[0007]

Means for Solving the Problems The present inventors have conducted intensive studies to develop a heat-sensitive water-separating agent having specific physical properties. A thermosensitive polymer or copolymer exhibiting a change in hydrophobicity, in which a part of the monomer units constituting the molecular chain is replaced by a reactive surfactant unit, the syneresis phenomenon occurs when an aqueous solution is used. In addition, the gelation was performed while maintaining the initial shape, and the dimensions were shrunk and solidified while releasing water. Was completed.

That is, the present invention relates to the following (A):

Embedded image (Wherein R ¹ is a hydrogen atom or a methyl group, at least one of R ² and R ³ is an ethyl group or a linear, branched or cyclic propyl group, and the rest is a hydrogen atom). It is composed of a structural unit derived from a monomer and (B) a structural unit derived from an anionic reactive surfactant, and the content of (B) is 0.001 to 10 mol based on the total amount of the copolymer. %, And a weight-average molecular weight in the range of 1,000,000 to 10,000,000, a thermosensitive synergic agent comprising an aqueous solution containing a copolymer exhibiting a low-temperature hydrophilicity-high-temperature hydrophobicity change, ( A) a structural unit derived from the monomer represented by the general formula (I);
(A ′) a mixed unit with a structural unit derived from a monomer that forms a polymer that does not exhibit a reversible change in low-temperature hydrophilicity-high-temperature hydrophobicity when polymerized alone; and (B) anionic reactive surface activity And the structural unit (A ′) is 7 per 100 parts by mass of the structural unit (A).
0 parts by mass, the content of (B) is in the range of 0.001 to 10 mol% based on the total amount of the copolymer, and the mass average molecular weight is 1,000,000 to 10,000.
A thermosensitive water-release agent comprising an aqueous solution containing a copolymer exhibiting a change in low-temperature hydrophilicity-high-temperature hydrophobicity in the range of 000, and a monomer represented by the above general formula (I) or An aqueous solution containing a mixture with a monomer that forms a polymer that does not show a reversible change in low-temperature hydrophilicity-high-temperature hydrophobicity when polymerized alone and an anionic reactive surfactant at a concentration equal to or higher than the critical micelle concentration thereof, In the presence of a radical polymerization initiator, the mass average molecular weight is 1,000,000 to 10,000 at a temperature equal to or higher than the hydrophilic-hydrophobic transition temperature of the resulting copolymer.
Another object of the present invention is to provide a method for producing a water releasing agent, which comprises copolymerizing in a micelle until the amount reaches the range of 1,000,000.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The heat-sensitive polymer compound exhibiting a reversible low-temperature hydrophilicity-high-temperature hydrophobicity change used in the present invention is a conventionally known low-temperature hydrophilicity-high-temperature hydrophobic thermoreversible polymer or copolymer. It is a copolymer having a molecular structure in which a part of the constituent monomer units of the union is substituted with a constituent unit derived from an anionic reactive surfactant.

[0010] Such a copolymer has a low-temperature hydrophilicity when it is polymerized alone by the above-mentioned general formula (I).
A monomer that forms a polymer exhibiting a reversible change in high-temperature hydrophobicity or low-temperature hydrophilicity-high-temperature hydrophobicity when polymerized alone with it.
It is produced by copolymerizing a mixture with a copolymerizable monomer which forms a polymer not shown , and (B) an anionic reactive surfactant.

[0011] All the monomer represented by the general formula (I)
And the alkyl group of R ² and R ³ has the number of carbon atoms
2 to 10 linear, branched and cyclic alkyl groups
be able to. Such as, for example, ethyl
Group, n-propyl group, isopropyl group, n-butyl group,
Isobutyl group, sec-butyl group, tert-butyl
Group, pentyl group, hexyl group, octyl group, cyclopro
Pill, cyclobutyl, cyclopentyl, cyclohexyl
And a xyl group. The alcohol of R ² and R ³
As the xyalkyl group, a straight-chain, branched
And branched and cyclic alkoxyalkyl.
You. Such include, for example, methoxymethyl
Group, methoxyethyl group, methoxypropyl group, ethoxy
Methyl group, ethoxyethyl group, ethoxypropyl group,
Sopropoxymethyl group, isopropoxyethyl group, iso
Propoxypropyl group, cyclopropoxymethyl group,
2,2-dimethoxyethyl group, 1-methyl-2-methoxy
Siethyl group, 1-methoxymethylpropyl group, methoxy
An ethoxypropyl group. The R ² and R ³ flags
May be the same or different.
A complex in which a nitrogen atom is a heteroatom bonded to each other
It may form a ring. Therefore, in general formula (I)
Examples of monomers represented are Nn-propyl
Lylamide or methacrylamide, N-isopropyl
Ruacrylamide or methacrylamide, N-cyclo
Lopropylacrylamide or methacrylamide,
N, N-diethylacrylamide or methacrylure
Amide, N-methyl-N-ethylacrylamide or
Methacrylamide, N-methyl-NN-propylac
Lilamide or methacrylamide, N-methyl-N
-Isopropylacrylamide or methacrylamido
De, N-acryloyl or methacryloyl piperidine
, N-acryloyl or methacryloyl pyrrolidine
, N-acryloyl or methacryloyl morpholy
, N-methoxypropylacrylamide or meth
Acrylamide, young N- ethoxypropyl acrylate amide
Or methacrylamide, N-isopropoxypropyl
Acrylamide or methacrylamide, N-ethoxy
Ciethylacrylamide or methacrylamide, N
-(2,2-dimethoxyethyl) -N-methylacryl
Amide or methacrylamide, N-1-methyl-2
-Methoxyethylacrylamide or methacrylure
Mido, N-1-methoxymethylpropylacrylamide
Or methacrylamide, N-di (2-methoxyethyl
G) acrylamide or methacrylamide, N-2
-Methoxyethyl-Nn-propylacrylamide
Or methacrylamide, N-2-methoxyethyl-N
-Ethylacrylamide or methacrylamide, N
-2-methoxyethyl-N-isopropylacrylamido
Or methacrylamide, N-methoxyethoxy
Propylacrylamide or methacrylamide, N-
Tetrahydrofurfurylacrylamide or methac
Lilamide, N- (1,3-dioxolan-2-yl)
Methylacrylamide or methacrylamide, N-
Methyl-N- (1,3-dioxolan-2-yl) methyl
Ruacrylamide or methacrylamide, N-cyclo
Lopropylacrylamide or methacrylamide,
N-pyrrolidinomethylacrylamide or methacrylic
Luamide, N-piperidinomethylacrylamide
Is methacrylamide, N-2-morpholinoethylacryl
Rate or methacrylate, N-2-morpholinoe
Toxiethyl acrylate or methacrylate
There is. In addition, 8-acryloyl-1,4-dioki
Spiro type such as sa-8-azaspiro [4,5] decane
Compounds can also be used. Especially suitable among them
Is N-isopropylacrylamide, Nn-propylacrylamide and N, N-diethylacrylamide. In the present invention, these monomers are used alone.
Or a combination of two or more of these
May be used.

Next, the above monomers are each independently
Or when polymerization or copolymerization in combination of two or more,
Polymers exhibiting reversible hydrophilic-hydrophobic changes with temperature
Is to form a copolymer, but in the present invention
Is polymerized singly with at least one such monomer.
Do not show a reversible change in low-temperature hydrophilicity-high-temperature hydrophobicity
Combination with at least one monomer that forms a new polymer
They can also be used together.

As described above, monomers which are used in combination with the monomer of the general formula (I) and form a polymer which does not show a reversible change in low-temperature hydrophilicity-high-temperature hydrophobicity when polymerized alone are: Unsaturated carboxylic acids such as acrylic acid and methacrylic acid, methyl acrylate or methacrylate, ethyl acrylate or methacrylate, n-butyl acrylate or methacrylate, tert-butyl acrylate or methacrylate, 2-ethylhexyl acrylate or methacrylate, 2-acetoacetoxyethyl acrylate Or methacrylate, 2-acetoacetoxypropyl acrylate or methacrylate, 3-acetoacetoxypropyl acrylate or methacrylate, 4-cyanoacetoacetoxyethyl acetate Relate or methacrylate,
Acrylates and methacrylates such as 2-hydroxyethyl acrylate or methacrylate, 3-hydroxypropyl acrylate or methacrylate, acrylamide or methacrylamide, N-methylolacrylamide or methacrylamide, N-hydroxypropylacrylamide or methacrylamide Unsaturated hydrazides such as acrylamides and methacrylamides, N-acryloylbenzhydrazides, N-methacryloylbenzhydrazides, unsaturated nitriles such as acrylonitrile, methacrylonitrile, vinyl acetate, vinyl chloride, styrene, α Vinyl compounds such as -methylstyrene, N-vinylimidazole, vinylmethylether, vinylethylether At least selected from the group consisting of class 1
Is a seed.

[0014] In the case of using these monomers, the weight alone
When combined, shows a reversible change in low-temperature hydrophilicity-high-temperature hydrophobicity.
It is preferably used in a proportion not exceeding 70 parts by mass per 100 parts by mass of the monomers forming the polymer . If the amount is larger than this, it becomes difficult to provide a copolymer that exhibits a reversible change in hydrophilicity / hydrophobicity.

Next, in the heat-sensitive polymer compound exhibiting a reversible change in low-temperature hydrophilicity- high- temperature hydrophobicity used in the present invention, an anionic reactive surface activity introduced as a part of a constituent unit of a molecular chain. The unit of the agent is derived from the component (B) described above, that is, an unsaturated compound generally known as an anionic reactive surfactant. The anionic reactive surfactant among them is a compound having a radical polymerizable ethylene bond in the molecule, a hydrophobic group and an anionic hydrophilic group at the same time, and has such a requirement. As long as there is no particular limitation.

As such a compound, for example,

Embedded image (Wherein R ′ is a higher alkyl group, A ¹ is an alkylene group,
M is an alkali metal or ammonium group, and n is an integer of 2 to 20) glycerol-1-allyl-
3-long-chain alkylphenyl-2-polyoxyethylene sulfate, general formula

Embedded image (Wherein R 'and M are the same as defined above), a long-chain alkylsulfosuccinic acid alkenyl ester salt represented by the general formula:

Embedded image (Wherein R ″ is a hydrogen atom or a methyl group, A ¹ , M and n
Are the same as those described above), and polyoxyethylene (meth) acrylate sulfate salts.

The reactive anionic surfactant can be obtained as a commercial product. That is, glycerol-1-allyl-3-long-chain alkylphenyl-2-polyoxyethylene sulfate compound is, for example,
As “Adecaria Soap SE-10N” and “Adecaria Soap SE-20N” [all trade names, manufactured by Asahi Denka Co., Ltd.], a long-chain alkylsulfosuccinic acid alkenyl ester salt type reactive surfactant is, for example, “ Eleminor JS-
2 "[manufactured by Sanyo Chemical Co., Ltd., trade name], and polyoxyethylene (meth) acrylate sulfate ester type compound is obtained, for example, as" Eleminol RS-30 "[manufactured by Sanyo Chemical Co., Ltd., trade name]. It is possible. These reactive surfactants may be used alone or in combination of two or more.

Low-temperature hydrophilicity- high-temperature hydrophobicity usable in the present invention
The anionic reactive surfactant unit in the thermosensitive polymer compound showing the reverse change is 0.0% based on the total monomer unit.
It is contained at a rate of 01 to 10 mol%, preferably 0.01 to 8 mol%. If the amount of the anionic reactive surfactant unit is smaller than this, a polymer or copolymer having a high molecular weight cannot be obtained, and if it is larger than this, the original property of heat sensitivity is impaired.

Low-temperature hydrophilicity- high-temperature hydrophobicity usable in the present invention
The thermosensitive polymer compound showing the reverse change is an aqueous solution at a predetermined temperature or lower than the transition temperature in an aqueous medium,
It has the property of thickening at higher temperatures, solidifying while maintaining the initial shape, shrinking while releasing water, and further solidifying, but showing such properties at a low concentration To achieve a weight average molecular weight of 1,000,000
It is necessary to be a high molecular weight polymer or copolymer as described above. However, if the molecular weight is too high, the viscosity becomes high even at a temperature lower than the transition temperature, and the application field is limited. Therefore, the molecular weight is preferably set to 10,000,000 or less. Further, the weight average molecular weight is 1,000,000
When used as a high-concentration aqueous solution even if the concentration is lower than the above, the above-mentioned properties are exhibited.

In order to produce a heat-sensitive polymer compound exhibiting such a low-temperature hydrophilic- high-temperature hydrophobic reversible change, an aqueous solution containing the above-mentioned component (A) and the above-mentioned component (B) is used. Polymerization is performed by a conventionally known radical polymerization method. In this case, the concentration of the aqueous solution is usually selected in the range of 2 to 15% by mass based on the total amount of the monomers, but the concentration of the reactive surfactant is critical in order to perform intra-micellar polymerization. It is necessary to select a concentration higher than the micelle concentration. This concentration range is usually 0.001 to 10 mol%, preferably 0.01 to 8 mol%, based on the total amount of the monomers. The anionic reactive surfactant functions as an emulsifier in a polymerization reaction for forming a predetermined polymer or copolymer. Conventionally, a corresponding cationic surfactant or anionic surfactant containing no ethylenically unsaturated bond was used as an emulsifier, but these remained in the reaction mixture after the polymerization was completed, and the produced heavy Since there is a risk of contamination by being mixed into the coalesced or copolymer, it was necessary to perform a special removal treatment. On the other hand, in the present invention, since this is taken into the molecule as a part of the structural unit, it is not necessary to perform such a removal treatment.

As means for initiating polymerization, a conventionally known means, for example, a method of irradiating with radiation or an electron beam, a method of heating in the presence of a radical polymerization initiator, a method of irradiating light in the presence of a photosensitizer And the like. Among these methods, a method of heating in the presence of a radical polymerization initiator is preferable. The radical polymerization initiator is not particularly limited as long as it is a water-soluble one. For example, ammonium persulfate, potassium persulfate, hydrogen peroxide, tert-
Butyl hydroperoxide, or a redox initiator such as sulfite, hydrogen sulfite, ceric ammonium nitrate, and the like; furthermore, 2,2'-azobis-2-amidinopropane hydrochloride, 2,2'-azobis-2 , 4-
Azo compounds such as dimethylvaleronitrile and 4,4'-azobis-4-cyanovaleric acid and salts thereof can be used. These radical polymerization initiators may be used alone or in combination of two or more. The amount used is usually 0.1 to the total amount of the monomers.
The range is from 01 to 100% by mass, and preferably from 0.05 to 8% by mass.

The reaction temperature varies depending on the type of the monomer and the initiator used, but is usually selected from the range of 0 to 100 ° C. The reaction temperature must be equal to or higher than the transition temperature of the aqueous copolymer solution produced by the polymerization. At a lower temperature, the viscosity increases during the reaction, and the polymerization does not proceed sufficiently. This polymerization needs to be carried out until the obtained copolymer has a mass average molecular weight of 1,000,000 or more.

By reacting in this way, a copolymerization reaction takes place in the micelle, and a copolymer can be obtained efficiently. After completion of the polymerization, the reaction solution is cooled to a temperature lower than the transition temperature of the produced copolymer, and when the aqueous solution is heated again to a temperature higher than the transition temperature, the polymer compound becomes hydrophobic and precipitates.
By repeating the operation of dissolving the precipitated polymer compound in pure water, heating and depositing the polymer compound, a copolymer from which unreacted monomers have been completely removed can be obtained.

The fact that the copolymer thus obtained contains an anionic reactive surfactant unit as a constitutional unit of its molecular chain is that its characteristic peak is recognized in the infrared absorption spectrum and that the It has been confirmed that the content of the anionic reactive surfactant in the copolymer does not decrease even if the washing with water is repeated.

Low temperature hydrophilicity- high temperature hydrophobicity usable in the present invention
A thermosensitive polymer compound showing a reverse change is water-soluble below the transition temperature, increases in viscosity above the transition temperature,
It has a specific property of gelling while maintaining its initial shape, shrinking while releasing water, and further solidifying. Therefore, the reaction solution obtained by the polymerization reaction is a bluish dispersion having a viscosity close to that of pure water when the temperature is maintained at or higher than the temperature at the time of polymerization, that is, the transition temperature of the produced copolymer. When is cooled to a temperature lower than the transition temperature, the micellar structure is destroyed, and the copolymer molecules dissolve in water, transforming into a transparent ultrahigh-viscosity aqueous solution. When this aqueous solution is heated again, the viscosity decreases as the temperature rises until the transition temperature is reached. However, when the aqueous solution exceeds the transition temperature, entanglement of the copolymer molecules occurs, and the viscosity rapidly increases. Then, the gel is gelled in the initial shape, for example, the container shape, and when left still, it condenses while separating water while maintaining its shape, and finally becomes an opaque solid. The present invention is a water release agent using a heat-sensitive polymer compound exhibiting such a reversible change in low-temperature hydrophilicity- high-temperature hydrophobicity. This low
The transition temperature of a heat-sensitive polymer compound exhibiting a reversible change in warm hydrophilic- high temperature hydrophobicity can be adjusted by changing the ratio of each component in the monomer mixture or adding a salt or alcohol to the medium. it can.

The water-releasing agent of the present invention needs to use at least a thermosensitive polymer compound having a weight average molecular weight of 1,000,000 as an aqueous solution having a concentration of 2% by mass or more.
If a polymer material having a lower molecular weight than this or an aqueous solution having a low concentration is used, it will not solidify even if left at a transition temperature or lower for a long time. The mass average molecular weight of a polymer material suitable for use as a water separating agent is 1,000,000 to 1
0,000,000 and the aqueous solution concentration is 2
-30% by mass.

This water-repelling agent can be used, for example, for treating waste liquid produced during the production of shochu. That is,
For waste liquid containing residue after collecting shochu by distillation,
Based on the mass of the solid content therein, an aqueous solution containing 0.5 to 5.0 times the amount of the heat-sensitive polymer material is added at a temperature lower than the transition temperature, and then the temperature is gradually increased, and the temperature is increased to the transition temperature or higher. When the heat-sensitive polymer material gels while capturing the solids in the waste liquid, if left at the same temperature, it gradually condenses while separating water, and finally only the solids in the waste liquid are highly heat-sensitive. Since it solidifies together with the molecular material, by removing it from the water, solid-liquid separation of the waste liquid can be performed.

[0028]

Next, the present invention will be described in more detail by way of examples. The mass average molecular weight of the copolymer in each example was measured by the following method. Measurement of mass average molecular weight: TSKgelH _HR type GMH _HR -H was used as an analytical column, and N, N-dimethylformamide containing 50 mmol% LiBr was used as an eluent at 40 ° C. by Tosoh HLC-8120GPC. The obtained values are values in terms of ethylene glycol and polyethylene oxide.

Reference Example 1 200 ml of distilled water was placed in a 500 ml Erlenmeyer flask equipped with a U-tube equipped with a cab and a condenser.
The amount of N-isopropylacrylamide (NIPA
Am) and glycerol-1-allyl-3-long-chain alkylphenyl-2-polyoxyethylene sulfate ester-type reactive surfactant [Adekalyapse SE-10N manufactured by Asahi Denka Co., Ltd.] And nitrogen gas 30
She passed hard for a minute. Then, ammonium persulfate (A
P) Add 0.05 g and stir under a nitrogen stream.
The polymerization was started by heating to 60 ° C. After polymerization at 60 ° C. for 2 hours, air was blown in to stop the polymerization, and a copolymer was produced. After completion of the polymerization, the reaction solution was cooled to a transition temperature or lower and then heated to precipitate a copolymer. Then
The precipitated copolymer was dissolved in pure water and freeze-dried to obtain a copolymer having a reactive surfactant unit content shown in Table 1.

[0030]

[Table 1]

The copolymer no. Using No. 1, a 5% by mass aqueous solution was prepared. 2.63 g of this aqueous solution
Was placed in a cylindrical sample tube having a diameter of 15 mm, and allowed to stand in a thermostat at 50 ° C. for 2.5 hours. Next, the solid-liquid separation was performed, and the amount of water separation was measured to be 2.15 g. The water separation rate at this time is 86%. In addition, No. FIG. 1 is a graph showing the relationship between temperature and viscosity for the copolymer No. 1.
In the figure, a is a change in viscosity in the case of pure water, b is a change in viscosity when the reaction solution at 60 ° C is cooled to 0 ° C,
c is a change in viscosity when the aqueous solution after the operation of b is heated again from 0 ° C.

Reference Example 2 In a 500 ml Erlenmeyer flask equipped with a U-tube equipped with a cab and a condenser, 200 g of distilled water and Nn-
27.61 g of propylacrylamide and 0.70 g of the same reactive surfactant used in Reference Example 1 were charged,
Nitrogen gas was passed vigorously for 30 minutes. Next, 0.05 g of ammonium persulfate was added, and the mixture was heated to 60 ° C. while stirring under a nitrogen stream to start polymerization. After polymerization at 60 ° C. for 2 hours, air was blown in to terminate the polymerization. After completion of the polymerization, the reaction solution was cooled to a transition temperature or lower and then heated again to precipitate a copolymer. The precipitated solid was dissolved in pure water and freeze-dried to obtain 28.2 g of a copolymer containing 0.33 mol% of a reactive surfactant unit.
Got. The molecular weight of the obtained copolymer was 2.17 million. Next, 3.04 g of a 5% by mass aqueous solution of this copolymer was placed in a cylindrical sample tube having a diameter of 1.5 cm, and this was placed at 50 ° C.
Was kept in a constant temperature bath for 3 hours to be separated. The mass of the water separated from the sample tube was measured and found to be 2.24 g. The water separation rate at this time is 75%.

Reference Example 3 In a 500 ml Erlenmeyer flask equipped with a U-tube equipped with a capillaries and a condenser, 200 g of distilled water, N, N-
27.32 g of diethylacrylamide and 0.70 g of the same reactive surfactant used in Reference Example 1 were charged,
Nitrogen gas was passed vigorously for 30 minutes. Next, 0.05 g of ammonium persulfate was added, and the mixture was heated to 60 ° C. while stirring under a nitrogen stream to start polymerization. After reacting at 60 ° C. for 2 hours, air was blown in to stop the polymerization. After completion of the polymerization, the reaction solution was cooled to a transition temperature or lower and then heated to precipitate a copolymer. The precipitated solid was dissolved in pure water and freeze-dried to obtain 28.0 g of a copolymer containing 0.34 mol% of a reactive surfactant unit. The molecular weight of the obtained copolymer was 2.16 million. Next, 4.99 g of a 5% by mass aqueous solution of the copolymer was placed in a cylindrical sample tube having a diameter of 1.5 cm, and kept in a 50 ° C constant temperature bath for 3 hours to separate water. The mass of the water separated from the sample tube was measured and found to be 3.46 g. The water separation rate at this time is 73%.

Reference Example 4 In a 500 ml Erlenmeyer flask equipped with a U-tube equipped with a cab and a condenser, 200 g of distilled water, 24.03 g of N-isopropylacrylamide, 3.00 g of Nt-butylacrylamide, and 0.70 g of the same reactive surfactant used in Example 1 was charged, and nitrogen gas was added to 3 g.
She passed hard for 0 minutes. Then, 2,2'-azobis (2
-Amidinopropane) hydrochloride (0.03 g) was added, and the mixture was heated to 60 ° C. while stirring under a nitrogen stream to initiate polymerization. After polymerization was performed at 60 ° C. for 3 hours, air was blown to stop the polymerization. After the completion of the polymerization, the reaction solution was cooled to a transition temperature or lower and then heated again to precipitate a copolymer. The precipitated solid was dissolved in pure water and freeze-dried to obtain 27.5 g of a copolymer containing 0.34 mol% of a reactive surfactant unit. The molecular weight of the obtained copolymer is 2
It was 550,000. Next, 4.99 g of a 5% by mass aqueous solution of the copolymer was placed in a cylindrical sample tube having a diameter of 1.5 cm,
This was kept in a constant temperature bath at 50 ° C. for 3 hours to separate water. When the mass of water separated from the sample tube was measured, it was 4.08 g.
Met. The water separation rate at this time is 86.1%.

Reference Example 5 In a 500 ml Erlenmeyer flask equipped with a U-tube equipped with a cab and a condenser, 200 g of distilled water, 24.03 g of N-isopropylacrylamide, 2.38 g of N, N-dimethylacrylamide, and 0.70 g of the same reactive surfactant used in Example 1 was charged, and nitrogen gas was passed vigorously for 30 minutes. Next, 0.06 g of 2,2'-azobisisobutyronitrile was added, and the mixture was heated to 60 ° C while stirring under a nitrogen stream to initiate polymerization. 60
After performing the reaction at 2 ° C. for 2 hours, air was blown in to terminate the polymerization. After completion of the polymerization, the reaction solution was cooled to a transition temperature or lower and then heated to precipitate a copolymer. The precipitated solid was dissolved in pure water and freeze-dried to obtain a copolymer 27.5 containing 0.34 mol% of a reactive surfactant unit.
g was obtained. The molecular weight of the obtained copolymer was 2,480,000. Next, 3.72 g of a 5% by mass aqueous solution of the copolymer was placed in a cylindrical sample tube having a diameter of 1.5 cm, and this was placed at 50 ° C.
Was kept in a constant temperature bath for 3 hours to be separated. The mass of the water separated from the sample tube was measured and found to be 2.80 g. The water separation rate at this time was 79.3%.

REFERENCE EXAMPLE 6 Distilled water (200 g), N-isopropylacrylamide (32.56 g), N-vinylimidazole (4.78 g) and Reference Example 1 were placed in a 2000 ml Erlenmeyer flask equipped with a U-tube and equipped with a cab and a condenser. 1.40 g of the same reactive surfactant as used in 1 was charged, and nitrogen gas was passed vigorously for 30 minutes. Then, ammonium persulfate 0.05
g and heated to 60 ° C. while stirring under a nitrogen stream to initiate polymerization. After reacting at 60 ° C. for 3 hours, air was blown in to stop the polymerization. After polymerization,
The reaction solution was cooled to a transition temperature or lower and then heated to precipitate a copolymer. The precipitated solid was dissolved in pure water and lyophilized to obtain 38.1 g of a copolymer containing 0.46 mol% of a reactive surfactant unit. The molecular weight of the obtained copolymer was 15.10 million. Next, 5.17 g of a 5% by mass aqueous solution of the copolymer was placed in a cylindrical sample tube having a diameter of 1.5 cm, and this was kept in a thermostat at 50 ° C. for 3 hours to be separated. The mass of the water separated from the sample tube was measured and found to be 4.47 g. The water separation rate at this time is 91%.

REFERENCE EXAMPLE 7 800 g of distilled water, 32.65 g of N-isopropylacrylamide, 2.31 g of acrylic acid, and 2.3 g of acrylic acid were used in a 2000 ml Erlenmeyer flask equipped with a U-tube equipped with a cab and a condenser. 1.40 g of the same reactive surfactant as above was charged, and nitrogen gas was passed vigorously for 30 minutes. Next, 0.05 g of ammonium persulfate was added,
The mixture was heated to 60 ° C. while stirring under a nitrogen stream to initiate polymerization. After reacting at 60 ° C. for 2 hours, air was blown in to stop the polymerization. After completion of the polymerization, the reaction solution was cooled to a transition temperature or lower and then heated to precipitate a copolymer. The precipitated solid was dissolved in pure water and freeze-dried to obtain 36.30 g of a copolymer containing 0.50 mol% of a reactive surfactant unit. The molecular weight of the obtained copolymer was 1.6 million. Next, 5.02 g of a 5% by mass aqueous solution of this copolymer was placed in a cylindrical sample tube having a diameter of 1.5 cm, and this was kept in a thermostat at 50 ° C for 3 hours to be separated.
When the mass of the water separated from the sample tube was measured, it was 4.1.
It was 0 g. The water separation rate at this time is 86.0%.

Reference Example 8 In a 500 ml Erlenmeyer flask equipped with a U-tube equipped with a cab and a condenser, distilled water 200 g, N-isopropylacrylamide 9.08 g, and a long-chain alkylsulfosuccinic acid alkenyl ester salt type reaction Surfactant [Sanyo Kasei Co., Ltd., trade name "Eleminol JS-
2 ", active ingredient 38%], 1.84 g, and vigorously passed nitrogen gas for 30 minutes. Next, 0.05 g of ammonium persulfate was added, and while stirring under a nitrogen stream, 60 g was added.
C. to start the polymerization. After reacting at 60 ° C. for 2 hours, air was blown in to stop the polymerization. After completion of the polymerization, the reaction solution is cooled to a transition temperature or lower and then heated,
The copolymer was precipitated. Dissolve the precipitated solid in pure water,
By performing freeze-drying, the reactive surfactant unit 1.
9.60 g of a copolymer containing 99 mol% was obtained. The molecular weight of the obtained copolymer was 1.5 million. Next, 5.20 g of a 5% by mass aqueous solution of the copolymer was placed in a cylindrical sample tube having a diameter of 1.5 cm, and this was kept in a 50 ° C constant temperature bath for 3 hours to be separated. The mass of the water separated from the sample tube was measured and found to be 4.21 g. The water separation rate at this time is 8
It is 5.2%.

REFERENCE EXAMPLE 9 200 g of distilled water, 9.08 g of N-isopropylacrylamide and polyoxyethylene (meth) acrylate sulfate were placed in a 500 ml Erlenmeyer flask equipped with a U-tube equipped with a cab and a condenser. Reactive surfactant [trade name “Eleminol RS” manufactured by Sanyo Chemical Industries, Ltd.
-30 ", 50% active ingredient] and nitrogen gas was vigorously passed for 30 minutes. Next, add 0.05 g of ammonium persulfate and stir under a nitrogen stream.
The polymerization was started by heating to 60 ° C. After reacting at 60 ° C. for 2 hours, air was blown in to stop the polymerization. After completion of the polymerization, the reaction solution was cooled to a transition temperature or lower and then heated to precipitate a copolymer. The precipitated solid was dissolved in pure water and freeze-dried to obtain 9.78 g of a copolymer containing 1.21 mol% of a reactive surfactant unit. The molecular weight of the obtained copolymer was 1.2 million. Next, 4.50 g of a 5% by mass aqueous solution of this copolymer was weighed 1.5 cm in diameter.
And kept in a thermostat at 50 ° C. for 3 hours to separate water. The mass of the water separated from the sample tube was measured and found to be 3.65 g. The water separation rate at this time is 85.5%.

Reference Example 10 In a 500 ml Erlenmeyer flask equipped with a U-tube and equipped with a cab and a condenser, 200 g of distilled water, 16.31 g of N-isopropylacrylamide, and vinyl acetate.
09g and a long-chain alkylsulfosuccinic acid alkenyl ester salt type reactive surfactant [manufactured by Sanyo Chemical Co., Ltd., trade name "Eleminol JS-2", active ingredient 38%] 0.70
g was charged and nitrogen gas was passed vigorously for 30 minutes. Next, 0.05 g of ammonium persulfate was added, and the mixture was heated to 60 ° C. while stirring under a nitrogen stream to start polymerization. After reacting at 60 ° C. for 2 hours, air was blown in to stop the polymerization. After completion of the polymerization, the reaction solution was cooled to a transition temperature or lower and then heated to precipitate a copolymer. By dissolving the precipitated solid in pure water and freeze-drying,
Copolymer 1 containing 0.34 mol% of a reactive surfactant unit
8.65 g were obtained. The molecular weight of the obtained copolymer is 180
It was ten thousand. Next, a 5% by mass aqueous solution of this copolymer was used.
2 g was placed in a cylindrical sample tube having a diameter of 1.5 cm, which was kept in a thermostat at 50 ° C. for 3 hours to allow water to separate. The mass of the water separated from the sample tube was measured and found to be 3.36 g. The water separation rate at this time is 84.2%.

REFERENCE EXAMPLE 11 In a 500 ml Erlenmeyer flask equipped with a U-tube equipped with a cab and a condenser, 200 g of distilled water, 10.19 g of N-isopropylacrylamide, 4.44 g of morpholinoethyl methacrylate and long-chain alkyl sulfo succinate were added. 0.70 g of an acid alkenyl ester salt type reactive surfactant [manufactured by Sanyo Chemical Co., Ltd., trade name "Eleminol JS-2", active ingredient 38%] was charged, and nitrogen gas was passed vigorously for 30 minutes. Then, 0.05 g of ammonium persulfate
Was added thereto, and the mixture was heated to 60 ° C. while stirring under a nitrogen stream to start polymerization. After reacting at 60 ° C for 2 hours,
The polymerization was stopped by blowing air. After completion of the polymerization, the reaction solution was cooled to a transition temperature or lower and then heated to precipitate a copolymer. The precipitated solid is dissolved in pure water and freeze-dried to obtain a reactive surfactant unit of 0.55 mol%.
14.32 g of a copolymer containing was obtained. The molecular weight of the obtained copolymer was 15.10 million. Next, 5 of this copolymer
4.5 g of a mass% aqueous solution was put into a cylindrical sample tube having a diameter of 1.5 cm, and this was kept in a thermostat at 50 ° C for 3 hours to be separated. When the mass of the water separated from the sample tube was measured,
3.73 g. The water separation rate at this time is 88.2%.

Reference Example 12 N-isopropylacrylamide and Nt as monomers
-Butyl acrylamide in various proportions, the same reactive surfactant used in Reference Example 1 was added thereto, and the mixture was polymerized under the same conditions as in Reference Example 4 to obtain a copolymer. Manufactured. The N- thus obtained
The relationship between the content of Nt-butylacrylamide in the mixture of isopropylacrylamide and Nt-butylacrylamide (shown as tBuAAm (mol%)) and the transition temperature (° C.) of the obtained copolymer is shown as a graph. As shown in FIG. As is apparent from this figure, the transition temperature can be changed by changing the component ratio in the monomer mixture.

The copolymer No. 1 obtained in Reference Example 1 was used. A 5% by weight aqueous solution of No. 1 was added in the amounts shown in Table 2 to potato shochu waste liquid (a), awamori waste liquid (b) and brown sugar waste liquid (c). Upon standing, the amount of transparent liquid shown in Table 2 was released, and a solid content was produced. Thus, the water-repellent agent of the present invention can be used for waste liquid treatment.

[0044]

[Table 2]

[0045]

The water-releasing agent of the present invention has a transition temperature below the transition temperature.
It shows almost the same viscosity as water, but has a unique property that it thickens when it exceeds the transition temperature, shrinks and releases water while maintaining its initial shape when it is kept at that temperature, and has the unique property of solidifying Therefore, for example, it can be suitably used for waste liquid treatment.

[Brief description of the drawings]

FIG. 1 is a graph showing the relationship between temperature and viscosity of one example of a heat-sensitive polymer material used in the present invention.

FIG. 2 is a graph showing a change in transition temperature due to a change in a monomer composition of a thermosensitive polymer material used in the present invention.

Claims (3)

(57) [Claims] (A) a general formula: (Wherein R ¹ is a hydrogen atom or a methyl group, at least one of R ² and R ³ is an ethyl group or a linear, branched or cyclic propyl group, and the rest is a hydrogen atom). It is composed of a structural unit derived from a monomer and (B) a structural unit derived from an anionic reactive surfactant, and the content of (B) is 0.001 to 10 mol based on the total amount of the copolymer. %, And a weight-average molecular weight in the range of 1,000,000 to 10,000,000, comprising an aqueous solution containing a copolymer exhibiting low-temperature hydrophilicity-high-temperature hydrophobicity change. (A) The general formula: (Wherein R ¹ is a hydrogen atom or a methyl group, at least one of R ² and R ³ is an ethyl group or a linear, branched or cyclic propyl group, and the rest is a hydrogen atom). mixing the hot hydrophobic reversible change not exhibit component unit derived from a monomer which forms a polymer - a structural unit derived from the monomer, (A') alone cold hydrophilic when polymerized with And (B) a structural unit derived from an anionic reactive surfactant, and a structural unit (A
') Is a range not exceeding 70 parts by mass per 100 parts by mass of the structural unit (A), the content of (B) is in the range of 0.001 to 10 mol% based on the total amount of the copolymer, and the mass average molecular weight is Is a range of 1,000,000 to 10,000,000, and is a heat-sensitive water-release agent comprising an aqueous solution containing a copolymer exhibiting a low-temperature hydrophilicity-high-temperature hydrophobicity change. 3. A compound of the general formula (Wherein R ¹ is a hydrogen atom or a methyl group, at least one of R ² and R ³ is an ethyl group or a linear, branched or cyclic propyl group, and the rest is a hydrogen atom). the monomer or the monomer, low hydrophilic when polymerized alone - mixtures and anionic its critical micelle concentration or more of the concentration of the monomers forming the polymer which does not exhibit hot hydrophobic reversible change An aqueous solution containing a reactive surfactant is prepared in the presence of a radical polymerization initiator at a temperature equal to or higher than the hydrophilic-hydrophobic transition temperature of the resulting copolymer and has a mass average molecular weight of 1,000,000 to 10,000, The method according to claim 1, wherein copolymerization in the micelle is performed until the molecular weight falls within a range of 000. 4.