JPH0569846B2 - - Google Patents

Description

[Detailed description of the invention]

Industrial Application Field The present invention provides a novel hydrophilic copper-chelating compound with copper chelating ability.
This invention relates to a hydrophobic thermoreversible copolymer. More specifically, the present invention provides copper that can be insolubilized by heating, which can be used in light shielding bodies, temperature sensors, adsorbents, copper ion indicators, toys, interior decorations, printing agents, displays, separation membranes, and mechanochemical materials. This invention relates to a hydrophilic-hydrophobic thermoreversible copolymer having chelating ability. Prior Art Some water-soluble polymer compounds exhibit a special reversible dissolution behavior in which they precipitate and become cloudy above a certain temperature (transition temperature or cloud point) in an aqueous solution state, and dissolve and become transparent below that temperature. Yes, this compound is called a hydrophilic-hydrophobic thermoreversible polymer compound, and in recent years it has been used as a light-shielding material in greenhouses, chemical laboratories, etc.
It has started to attract attention as a temperature sensor, etc. As such thermoreversible polymer compounds, partially saponified polyvinyl acetate, polyvinyl methyl ether, methylcellulose, polyethylene oxide, polyvinylmethyloxazolidinone, polyacrylamide derivatives, and the like have been known. Among these thermoreversible polymers, polyacrylamide derivatives are suitable for the above uses because they are stable in water and can be produced at relatively low cost.
So far, poly(N-ethyl(meth)acrylamide), poly(N-ethyl(meth)acrylamide), poly(N-ethyl(meth)acrylamide),
-n-propyl(meth)acrylamide), poly(N-isopropyl(meth)acrylamide), poly(N-cyclopropyl(meth)acrylamide), poly(N,N-diethylacrylamide),
poly(N-methyl-N-ethylacrylamide),
Poly(N,N-diethylacrylamide), poly(N-methyl-N-ethylacrylamide), poly(N-methyl-N-n-propylacrylamide), poly(N-methyl-N-isopropylacrylamide), poly( N-acrylpyrrolidine),
Poly(N-acrylicpiperidine), poly(N-tetrahydrofurfuryl(meth)acrylamide,
Poly(N-methoxypropyl(meth)acrylamide), Poly(N-ethoxypropyl(meth)acrylamide, Poly(N-isopropococypropyl(meth)acrylamide), Poly(N-ethoxyethyl(meth)acrylamide), Poly(N-ethoxypropyl(meth)acrylamide) −(2,
2-dimethoxyethyl)-N-methylacrylamide) and the like are known. However, even if we try to use such compounds for example in temperature sensors or light shields,
The transition temperature is limited, and since it does not have the ability to chelate metal ions, the range of application is inevitably limited. Problems to be Solved by the Invention Under these circumstances, the purpose of the present invention is to expand the scope of use of hydrophilic-hydrophobic thermoreversible polyacrylamide derivatives, which have copper chelating ability and can be heated The object of the present invention is to provide a novel hydrophilic-hydrophobic thermoreversible copolymer that is insolubilized in water. Means for Solving the Problems The present invention was developed as a result of intensive research and has been developed using the general formula CH ₂ = CR ₁ −CO−NH−NH−CO−C ₆ H ₅
...() (where R ₁ is a hydrogen atom or a methyl group) and a vinyl compound represented by the general formula

[Formula] (where R ₁ is the same as above, R ₂ and R ₃ are hydrogen atoms, alkyl groups, cycloalkyl groups, tetrahydrofurfuryl groups, alkoxyalkyl groups), and the homopolymer aqueous solution is thermoreversible. By copolymerizing a monomer mixture of a vinyl compound exhibiting a specific property or a monomer mixture in which a copolymerizable vinyl compound other than these is added, a hydrophilic-hydrophobic product with a copper chelating ability that becomes insoluble in water by heating. It was discovered that a thermoreversible copolymer could be obtained, and based on this knowledge, the present invention was completed. That is, the present invention provides (A) general formula

[Formula] (However, R ₁ is the same as above) and (B) General formula

[Formula] (where R ₁ , R ₂ and R ₃ are the same as above) (B) is in the range of 0.03 to 0.12, and the intrinsic viscosity [η] at 30℃ is 0.01 to
The present invention provides a hydrophilic-hydrophobic thermoreversible copolymer having a molecular weight corresponding to 6.0. The copolymer of the present invention can be obtained by copolymerizing the vinyl compound of the general formula () and the vinyl compound of the general formula () at a predetermined ratio. Furthermore, other vinyl compounds copolymerizable with these can be added and copolymerized. General formula used in the present invention () CH ₂ = CR ₁ -CO-NH-NH-CO-C ₆ H ₅ (When R ₁ = H, N-acryloylbenzhydrazide, hereinafter abbreviated as ABH, R ₁ = CH ₃ When , N-methacryloylbenzhydrazide, hereinafter abbreviated as
Homopolymers of vinyl compounds represented by MABH) are known to selectively chelate with copper ions, and this has been demonstrated, for example, by
Chemie), Vol. 85, pp. 92-105 (published in 1965). In the present invention, the general formula () whose homopolymers are all hydrophilic-hydrophobic thermoreversible polymers
One or more types of vinyl compounds represented by can be used. Specifically, these include N-ethyl (meth)acrylamide, N-n-propyl (meth)acrylamide, and N-isopropyl (meth)acrylamide.
Acrylamide, N-cyclopropyl (meth)acrylamide, N,N-diethylacrylamide, N-methyl-N-ethylacrylamide, N
-Methyl-N-n-propylacrylamide,
N-methyl-N-isopropylacrylamide,
N-acrylicpyrrolidine, N-acrylicpiperidine, N-tetrahydrofurfuryl (meth)acrylamide, N-methoxypropyl (meth)acrylamide, N-ethoxypropyl (meth)acrylamide, N-isopropococypropyl (meth)
Acrylamide, N-ethoxyethyl (meth)acrylamide, N-(2,2-dimethoxyethyl)-
Examples include N-methylacrylamide. In the present invention, other copolymerizable vinyl compounds that can be used as the third component include hydrophilic vinyl compounds (excluding the above thermoreversible vinyl compounds),
One or more types of ionic vinyl compounds and hydrophilic vinyl compounds can be used. Examples of the hydrophilic vinyl compound include N-methylolacrylamide, acrylamide, methacrylamide, N-methylacrylamide, N,N-dimethylacrylamide, acryloylmorpholine, diacetone acrylamide, hydroxyethyl methacrylate, hydroxymethyl methacrylate, hydroxymethyl acrylate, Hydroxypropyl methacrylate, hydroxypropyl acrylate, N
-Methoxypropyl acrylamide, N-methoxypropyl methacrylamide, 2-methyl-5-
Examples include vinylpyridine and N-vinyl-2-pyrrolidone. Examples of ionic monomers include acrylic acid, methacrylic acid, 2-acrylamido-2-methyl-propanesulfonic acid,
Acids such as styrene sulfonic acid and their salts N, N
-dimethylaminoacyl methacrylate, N,N
-diethylaminoethyl methacrylate, N,N
-diethylaminoethyl acrylate, N,N-
dimethylaminopropyl methacrylamide, N,
Amines such as N-dimethylaminopropylacrylamide and their salts can be mentioned. Examples of lipophilic vinyl compounds include N-n-butylacrylamide, N-butylmethacrylamide, N-sec-butylacrylamide, N-sec
Butyl methacrylamide, N-tert-butyl methacrylamide, N-tert-butyl methacrylamide, N-n-hexyl acrylamide, N-n-
N-alkyl (meth)acrylamide derivatives such as hexyl methacrylamide, (meth)acrylate derivatives such as ethyl acrylate, methyl methacrylate, butyl methacrylate, glycidyl methacrylate, acrylonitrile, vinyl acetate, vinyl chloride, styrene, α-methylstyrene, etc. I can give it to you. The usage ratio of the vinyl compound represented by the above general formula () and the vinyl compound represented by the general formula () is selected within the range of 0.03 to 0.12 mol of the former per 1 mol of the latter. If the proportion of the former used is lower than this, the transition temperature will be high and it will be difficult to use it practically, and if it is too large, it will become insolubilized. As a specific method for producing a hydrophilic-hydrophobic thermoreversible copolymer by copolymerizing the vinyl compound represented by the above general formulas () and () and the vinyl compound serving as the third component, for example, ( 1) A method of copolymerizing the monomer as it is without diluting it with a solvent, (2) A method of solution copolymerization by diluting the monomer with a solvent, (3) A method of suspension copolymerization, (4) A method of emulsion copolymerization. A method such as polymerization can be adopted. The polymerization mode at that time is radical polymerization.
Methods for starting polymerization include (1) using a polymerization initiator, (2) irradiation with light such as ultraviolet rays and visible light, (3) methods using heat, and (4) ionizing methods such as radiation, electron beams, and plasma. A method such as irradiation with energy rays can be adopted.
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, there are ammonium persulfate, potassium persulfate, hydrogen peroxide, tert-butyl peroxide, benzoyl peroxide, cumene hydroperoxide, etc. Reducing agents used in combination with these include sulfites, bisulfites, etc. . Examples of azo compounds include azobisisobutyronitrile, 2,2'-azobis-2-aminodipropane dihydrochloride, 2,2'-
azobis-2,4-dimethylvaleronitrile,
4,4'-azobis-4-cyanovaleic acid and the like can be used. In addition, 2 of the above polymerization initiators
It is also possible to use more than one species in combination. In this case, the amount of the polymerization initiator added is in the range of 0.01 to 5% by weight, preferably 0.05% to 2% by weight, based on the vinyl compound of the structural unit. In the present invention, a method of ordinary solution copolymerization is preferably used. In this solution copolymerization, a commonly known radical polymerization method can be used, in which two or more of the above-mentioned vinyl compounds are dissolved in a solvent to form a solution having a concentration of 1 to 80% by weight.
There are no particular restrictions on the solvent used in such solution copolymerization, but examples include water, alcohols,
N,N-dimethylformamide, N,N-dimethylacetamide, acetone, dioxane, tetrahydrofuran, benzene, chloroform, carbon tetrachloride, etc. may be used alone or in combination of two or more. The copolymer of the present invention thus obtained is
It has a polymer unit of general formula (1) in part, and forms a chelate with Cu ²⁺ ion according to the following formula.

[Chemical formula] Furthermore, the copolymer of the present invention has a polymer unit of the general formula (), and is soluble in water at low temperatures and insoluble at high temperatures, regardless of copper chelate formation. It has high-temperature hydrophobization type thermoreversibility. Generally, the transition temperature of an aqueous solution of a thermoreversible copolymer can be controlled by the types and combinations of vinyl compounds serving as constituent units and their composition ratios. In that case, in the case of a copolymer in which the homopolymer is formed of two or more thermoreversible vinyl compounds, additivity often exists between the transition temperature of each homopolymer and its composition. Further, the homopolymer may copolymerize one or more thermoreversible vinyl compounds with one or more other copolymerizable non-thermoreversible vinyl compounds. As other copolymerizable non-thermoreversible vinyl compounds, one or more of hydrophilic vinyl compounds, ionic vinyl compounds, and lipophilic vinyl compounds can be employed. In that case, the introduction of these vinyl compounds changes the transition temperature of the aqueous copolymer solution, but in general, introduction of a hydrophilic vinyl compound increases the transition temperature, while introduction of a small amount of lipophilic vinyl compound lowers the transition temperature. They tend to be processed. The introduction of large amounts of lipophilic vinyl compounds
Makes the copolymer water-insoluble. Regarding the copolymer of the present invention, since the homopolymer of the vinyl compound represented by general formula ( (ABH) component,
The (MABH) component is preferably 10% or less. The transition temperature of the copolymer aqueous solution of the present invention is determined by the general formula (), the vinyl compound represented by the general formula (), and other copolymerizable non-thermoreversible vinyl compounds, which are the constituent units in the copolymer. It can be estimated from the type, composition, and composition ratio.
Further, the transition temperature of the aqueous copolymer solution after copper chelation is generally lower than that of an unchelated copolymer, although it depends on the degree of chelate formation. The copolymer of the present invention was prepared on a methanol solution at 30°C.
It has a high molecular weight corresponding to an intrinsic viscosity [η] of 0.01 to 6.0, preferably 0.1 to 3.0. Effects of the Invention The acrylamide-based thermoreversible copolymer of the present invention has high-temperature hydrophobization type thermoreversibility that is soluble in water at low temperatures and insoluble in water at high temperatures, and
Unlike conventionally known thermoreversible acrylamide polymers, it has copper chelating ability, and the transition temperature can be varied over a wide range by combining vinyl compounds, making it suitable for light shielding materials,
It can be used in temperature sensors, adsorbents, copper ion indicators, toys, interiors, textile printing agents, displays, separation membranes, and mechanochemical materials. For example, if the copolymer of the present invention is laminated on a transparent plate in the form of an aqueous solution or in the form of a hydrogel or microcapsule, it will automatically prevent the room temperature from rising more than necessary due to direct sunlight. It is suitable as a light shielding body to prevent this. The present invention will be explained in more detail below using Examples. Examples 1 to 5 Using azobisisobutyronitrile as a polymerization initiator, a methanol solution with a concentration of 50 mg/1 ml was prepared.
A predetermined weight of two or more of the above-mentioned vinyl compounds was added to the ampoule, which was then degassed under reduced pressure using liquid nitrogen, sealed, and allowed to react at a temperature of 60° C. for 20 hours. After the reaction, methanol was evaporated, the solution was made into an acetone solution, and the copolymer was recovered by precipitation in diethyl ether. The thermoreversibility of this copolymer in water was investigated. The transition temperature was determined from the light transmittance associated with the temperature change of the aqueous solution. That is, a copolymer aqueous solution with a concentration of 1% by weight was prepared, and using a spectrophotometer with a temperature controller, the light transmittance at a wavelength of 500 nm was measured while increasing the temperature at a rate of 1°C/min, and the transition temperature was determined. was determined from the temperature (T _L ) at which this light transmittance becomes 0.5 of the initial transmittance.

【table】

[Table] These results are shown in Table 1. Further, the transmittance-temperature curves of the aqueous solutions of the copolymers of Examples 1, 2, and 4 are shown in FIG. Among these, the solid line is the data when the temperature is rising, and the dotted line is the data when the temperature is falling. Examples 2, 3, and 4 When copper sulfate was added to the copolymer aqueous solution, the color of the aqueous solution changed from blue to olive green, confirming the formation of copper chelate. The aqueous solution of the copper chelated copolymer produced showed thermoreversible dissolution properties. Examples 6 to 10 Add a predetermined weight of two or more of the above vinyl compounds to 20 ml of methanol solution, put this into an ampoule, degas it under reduced pressure using liquid nitrogen, then seal the tube, and set the irradiation dose rate to 3.9×10 ⁴ R. /hr, 10 at a temperature of 24℃
Gamma ray irradiation from cobalt-60 was performed for a period of time to cause a reaction. After the reaction, methanol was evaporated, the solution was made into an acetone solution, and the copolymer was recovered by precipitation in diethyl ether.

[Table] The thermoreversibility of these copolymer aqueous solutions was investigated using the above method. These results are shown in Table 2. Examples 7 and 8 When copper ions were added to the copolymer aqueous solution, the color of the aqueous solution changed from blue to olive green, confirming the formation of copper chelate.
Furthermore, the aqueous solution of the copper chelating copolymer produced showed thermoreversible dissolution characteristics. FIG. 2 shows the transmittance-temperature curves of the Example 7 copolymer and the copper-chelated Example 7 copolymer aqueous solution. Examples 11-24 Using azobisisobutyronitrile as a polymerization initiator, a methanol solution with a concentration of 5 mg/1 ml20
A predetermined amount of two or more of the above-mentioned vinyl compounds was added to the ampoule, which was then degassed under reduced pressure using liquid nitrogen, sealed, and allowed to react at a temperature of 60° C. for a predetermined time. After the reaction, the methanol was evaporated, an acetone solution was prepared, and the copolymer was precipitated in n-hexane to recover the copolymer. The thermoreversibility of these copolymer aqueous solutions was investigated using the method described above. These results are shown in Table 3. Examples 11-22 When copper ions were added to the copolymer aqueous solution, the color of the aqueous solution changed from blue to olive green, confirming the formation of copper chelate. Also,
The aqueous solution of the copper chelated copolymer produced showed thermoreversible dissolution properties.

【table】 [Brief explanation of the drawing]

Figures 1 and 2 are 1% by weight of the copolymer of the present invention.
The transmittance-temperature curve in an aqueous solution is shown.

Claims (1)

[Claims] 1 (A) A structural unit represented by the general formula [formula] (wherein R ₁ is a hydrogen atom or a methyl group), and (B) a general formula [formula] (wherein R ₁ is the same as the above) Same, R ₂ and R ₃ contain a hydrogen atom, a structural unit represented by an alkyl group, a cycloalkyl group, a tetrahydrofurfuryl group, or an alkoxyalkyl group, and the combination of the structural unit (A) and the structural unit (B) The molar ratio (A)/(B) is in the range of 0.03 to 0.12, and the intrinsic viscosity [η] at 30°C is 0.01 to
A hydrophilic-hydrophobic thermoreversible copolymer with a molecular weight corresponding to 6.0.