JPH06145216A - Production of weakly basic anion exchange resin - Google Patents

Abstract

PURPOSE:To obtain the subject exchange resin having excellent chemical stability, high weak-base exchange capacity and improved hydrophilic nature by copolymerizing a solution of vinylformamide and a polyethylenic monomer, treating with an acid and methylating the amino group. CONSTITUTION:A solution containing N-vinylformamide and a polyethylenic monomer is copolymerized in the presence of a polymerization initiator, the prepared copolymer is treated with an acid or under a basic condition, a formamide group is hydrolyzed into amino group and the amino group is methylated with a formaldehyde or formic acid (salt).

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing a weakly basic anion exchange resin. Furthermore, the present invention relates to a method for producing a novel weakly basic anion exchange resin having a polyvinylmethylamine and / or polyvinyldimethylamine structure.

[0002]

2. Description of the Related Art Resins called anion exchange resins and chelate resins are known to have chemical stability, mechanical strength and production cost, and the chloromethyl group of a styrene derivative-divinylbenzene copolymer is replaced with an alkylamine. Aminated anion exchange resins are commonly used.

However, the styrene type anion exchange resin has the following drawbacks. Benzyl group in component of the resin (-C ₆ H ₄ CH ₂
-) Does not participate in the ion exchange capacity at all. This causes the anion exchange capacity per unit weight to decrease. For example, the content of the cross-linking agent component having no ion-exchange group is extremely low (the content of the cross-linking agent is 0%), a styrene-based polymer (1 to 3 tertiary aminomethylstyrene type or quaternary ammonium methylstyrene type ) Is assumed, the maximum ion exchange capacity is 7.5 meq (hereinafter abbreviated as meq) / g in the case of the primary amine type.
(Represents a dry resin, the same applies hereinafter) In the case of a tertiary amine type, it is 6.2 meq / g. Since the conversion of the chloromethyl group, which is an intermediate in the reaction step, to the amino group does not proceed completely, some organic chlorine compounds remain after the amination. As a result, chlorine compounds leak out during use of the resin and in some cases the container corrodes. It has been pointed out that chloromethyl methyl ether used in the manufacturing process is a highly harmful substance, which is not preferable in terms of occupational safety and health. The intermediate of the reaction process is a lipophilic polymer. Therefore, in the reaction, as a good solvent for swelling the polymer, an organic solvent (for example, a hydrocarbon solvent such as toluene,
Chlorinated hydrocarbons such as dichloroethane) must be used. As a result, the recovery and treatment of organic solvents, especially the treatment of chlorine-based solvents, becomes a problem.

[0004]

In order to avoid the above-mentioned problems of the styrene-based anion exchange resin, the linear polyvinylamines are reacted with a polyfunctional crosslinking agent capable of reacting with the amino group of the linear polyvinylamines. A method for obtaining a gel-type cross-linked spherical resin has been proposed (see, for example, JP-A-61-161).
44902, JP-A-61-51006). Whereas linear polyvinylamine is water soluble,
Multifunctional crosslinkers are usually soluble in organic solvents. Both are separated into two phases, and a crosslinking reaction proceeds from the interface. as a result,
There are problems that the cross-linking of the linear polymer is not uniform and the reaction rate of adsorption and elution of the target is reduced. Furthermore, there are problems that the degree of crosslinking is not easily controlled, the physical properties of the polymer are not reproducible, and the tertiary amine cannot be selectively synthesized.

[0005]

The present invention is to solve the problems of the above-mentioned styrene type anion exchange resin and crosslinked linear polyvinylamine resin. That is, the gist of the present invention is to copolymerize a solution containing N-vinylformamide and a polyethylene monomer in the presence of a polymerization initiator, and treat the resulting copolymer under acid or basic conditions. Formamide group is hydrolyzed to an amino group, and then formaldehyde and, if necessary, formic acid or a salt thereof are added and reacted to methylate the amino group, thereby forming a weakly basic anion exchange resin. It depends on the manufacturing method.

In the present invention, first, in the presence of a crosslinking agent, NVF is used.
Is copolymerized and then hydrolyzed. The synthesis method of this polyvinylamine polymer is described in “Synthesis and Application of Reactive Polymer”, p1.
55 to p165 (CMC), there are various synthetic methods, and the NVF method is one of them. NVF used as a raw material monomer is inexpensive.
It is characterized by being easily hydrolyzed, having good copolymerizability with other monomer components, and being a water-soluble monomer.

The present invention further hydrolyzes the above polyvinylamine polymer to convert a formamide group into an amino group, and then utilizes formic acid by-produced by the hydrolysis to formaldehyde and, if necessary, formic acid or By further adding the salt, the methylation of the amine can be carried out efficiently and
Characterized by doing reasonably. By adopting such a method, it becomes possible to inexpensively produce a target weakly basic anion exchange resin having a secondary amino group or a tertiary amino group.

The present invention will be described in detail below. The resin of the present invention first copolymerizes NVF and a polyethylene monomer. In order to make the best use of the characteristics of NVF, the content of NVF is 0.1 to 99.5% by weight, and particularly preferably 20% to 95% by weight, based on all monomers. Examples of the polyethylene monomer include aromatic compounds having two or more ethylenically unsaturated double bonds such as divinylbenzene, divinyltoluene and divinylxylene, ethylene glycol di (meth) acrylate, diethylene glycol di (meth). Poly (meth) acrylates such as acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, glycerol di (meth) acrylate, trimethylolpropane tri (meth) acrylate And polyacrylamides such as ethylene bisacrylamide are preferred. These are used as a cross-linking agent and may be a mixture. The cross-linking agent is an essential constituent component for making the resulting polymer insoluble, and must be added to the extent that the significance of the constituent element of polyvinyl amine is not lost. Therefore, the amount of crosslinking agent added is
It is preferably 0.1% by weight to 60% by weight. Further, it is preferably 1% by weight to 30% by weight. The industrial standard purity of divinylbenzene, which is a typical cross-linking agent, is 56.5% (including ethyltoluene, methylstyrene, etc.). Therefore, when divinylbenzene is used, the addition amount depends on the purity. The required amount must be added accordingly. As a result, monomer components other than NVF and the cross-linking agent are mixed, but the present invention does not exclude them. When the content of the polyethylene monomer as the cross-linking agent component is high, the produced polymer tends to be porous. This can be confirmed by a method such as a specific surface area measuring method, but when the polymer is white or milky white in appearance, it is considered that the polymer is porous.

Furthermore, it is possible to intentionally add other monomers copolymerizable with NVF and a polyethylene monomer. For example, the general formula (I)

[0010]

[Chemical 1]

(In the formula, R ¹ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and Q represents an aryl group which may have a substituent or an alkyloxycarbonyl group (COO).
R), carbamoyl group, alkylamido group (NHCO
R) (R represents a substituent such as an alkyl group) or a cyano group), such as styrene, alkylstyrene, and (meth) acrylic acid ester. , Alkyl (meth) acrylates such as methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate and octyl (meth) acrylate, 2-hydroxyethyl (meth)
Acrylate, diethylene glycol (meth) acrylate, triethylene glycol (meth) acrylate,
Examples thereof include monomers such as polyethylene glycol (meth) acrylate such as octaethylene glycol (meth) acrylate, (meth) acrylic acid ester such as glycerol (meth) acrylate, (meth) acrylamide, and (meth) acrylonitrile. However, these monomer components such as (meth) acrylic acid are likely to be hydrolyzed to (meth) acrylic acid at the same time when the formamide group is hydrolyzed, so that the reaction conditions must be carefully considered.

The content of the units derived from the copolymerizable monomer is 0 to 70% by weight, preferably 0 to 40% by weight, based on the total amount of the copolymer. As the polymerization method in the present invention, various methods can be mentioned. When suspension polymerization is adopted, a spherical copolymer can be obtained. Further, in the case of solution polymerization, the shape of the copolymer depends on the container. After the polymerization, it is preferable to grind it to an appropriate size. Further, a porous resin is obtained by polymerizing in the presence of a porosifying agent.

When a spherical polymer is obtained by the suspension polymerization method,
It is manufactured by the following method. NVF is a water-soluble monomer, but is soluble in many organic solvents other than non-polar hydrocarbons. Therefore, water-in-oil suspension polymerization is preferred unless the NVF content is low. Conversely, when the NVF content is low, this is not the case, and oil-in-water suspension polymerization is preferred.
The solvent used as the bath in the suspension polymerization is an organic solvent that is sparingly soluble in NVF, such as toluene, petroleum ether, hexane,
Heptane, cyclohexane, isooctane, aliphatic such as octane, or aromatic hydrocarbon, dichloroethane, polychloroalkane, aliphatic such as chlorobenzene, dichlorobenzene, aromatic polyhalogen compounds can be used,
In particular, cyclohexane, petroleum ether, isooctane,
Heptane, hexane and the like are preferable.

The ratio of the polymerization bath in the suspension polymerization is the solubility of each organic solvent in water, the content of NVF and polyethylene monomer, the content of diluent, the method of charging the monomer,
Although it is determined by the dispersion stabilizer and the like, it is generally in the range of 1 to 5 volumes with respect to 1 volume of the monomer layer. N
VF has a poor compatibility with the polyethylene aromatic monomer and other monomer components. Therefore, a diluent may be added when the polyethylene aromatic monomer is dissolved in NVF. That is, as the solvent used as the diluent, for example, polar solvents such as water, dimethylsulfoxide, dimethylformamide, hexamethylphosphoric triamide, and mixed solutions of these solvents are preferable. The addition amount varies depending on the degree of swelling of the target polymer, mechanical strength, the addition amount of the crosslinking agent component, and the monomer component ratio, but it is 0 to 150% by weight based on the polymerizable monomer. Is preferred.

There are various methods for dropping the monomer,
For example, a continuous dropping method in which a monomer solution is gradually supplied to generate droplets while stirring the bath and a batch dropping method in which the monomer solution is collectively charged into the bath can be adopted. It may be appropriately selected depending on the purpose. The dispersion stabilizer in the present invention is appropriately selected depending on the polymerization method, the size of droplets and the like.
In the water-in-oil suspension polymerization method, oil-soluble cellulose such as ethyl cellulose, cellulose acetate butyrate, ethyl hydroxyethyl cellulose, or gum arabic, sorbitan sesquioleate, sorbitan mono are used as a dispersion stabilizer in a water-insoluble dispersion medium. It is preferable to add an oil-soluble dispersion stabilizer such as oleate or sorbitan monostearate.

In the oil-in-water suspension polymerization method, it is preferable to add a water-soluble dispersion stabilizer such as polyvinyl alcohol or polyvinylpyrrolidone as a dispersion stabilizer. The addition amount is usually 0.05% by weight to 5% by weight, preferably 0.1% by weight to 2% by weight, based on the dispersion medium. In the present invention, the average particle size of the resin is preferably 10 μm to 2 mm and is appropriately selected depending on the purpose of the resin. Usually, in the case of a general-purpose ion exchange resin, the particle size thereof is generally 50 μm to 2000 μm, particularly preferably 300 μm.
Is about 800 μm.

The polymerization initiator used in the present invention is selected from various polymerization initiators, and the persulfate polymerization initiator is
It is not preferable because the degree of polymerization does not increase and the polymerization yield decreases. Azo-based and peroxide-based polymerization initiators are preferred. Further, depending on the polymerization method, for example, in the case of water-in-oil suspension polymerization, the polymerization initiator is also preferably water-soluble.
For example, azo-based polymerization initiators such as 2,2-azobis-2-amidinopropane hydrochloride and 4,4-azobis-4-cyanovaleric acid are used. Conversely, in the case of oil-in-water suspension polymerization, AIBN is used. (Azobisisobutyronitrile), V-
A polymerization initiator soluble in an organic solvent such as 65 (trade name, Azobis-2,4-dimethylvaleronitrile manufactured by Wako Pure Chemical Industries, Ltd.) is used. The addition amount of the polymerization initiator is generally 0.02% by weight to 5.0% by weight, and more preferably 0.05% by weight to 2.0% by weight, based on the polymerizable monomer.
Although the polymerization conditions vary depending on the monomer components, the polymerization temperature is usually 30 to 120 ° C., and the polymerization time is usually 2 hours to 1
5 hours.

NVF is a water-soluble monomer, but it dissolves in many organic solvents other than nonpolar hydrocarbons (such as hexane). However, not all porosifying agents can be used, and examples include those having an organic solvent having a CLOGP value of -2.0 to +2.0. The CLOGP value in the present invention is obtained from University of Pomona (California) (T. Nishioka).
It was developed by (Kyoto Univ.) Program edited to FACOM 3.33 version and is defined as follows. The CLOGP value is a value obtained by calculating the logarithmic value (log ₁₀ P) of the partition coefficient of the solute in the 1-octanol / water system. When this CLOGP value is positive, it means that it is easier to partition into the organic solvent (1-octanol) than water. When the CLOGP value is within the above range, it means that the CLOGP value is relatively hydrophilic. In the case of a mixed solvent, the CLOGP value is defined as the average value of the sum of each CLOGP value. Examples of the porosifying agent that can be used in the present invention include acetone (-0.27), 1-propanol (0.29), 2-propanol (0.0
7), methanol (-0.76), ethanol (-0.
24), acetonitrile (-0.39), a single solvent such as methanol-1, propanol, methanol-1,
A mixed solvent of 4-dioxane, methanol-tetrahydrofuran, ethanol-1,4-dioxane and the like can be mentioned. Further, an aqueous solution of a water-soluble organic solvent having a CLOGP value in the range of -2.0 to +2.0 is also useful as a porosifying agent. When water, toluene, benzene, hexane, nitrobenzene, 1,2-dinitrobenzene or the like having a CLOGP value outside the above range is used, the obtained copolymer does not show a porous body.

In addition to the above porosifying agents, linear polymers compatible with the monomers can also be porosifying agents. Examples of linear polymers that can be used as the porosifying agent include polyvinylpyrrolidone, polyethylene glycol, ethyl cellulose and the like. The average molecular weight of the linear polymer is 10 ³
It is preferably from 10 ⁶ to 10. If the amount of the linear polymer added is large, the crosslinking agent may precipitate. In particular, since a hydrophobic cross-linking agent is likely to be deposited, a hydrophilic cross-linking agent is preferable in this case.

The physical properties of the pores of the porous structure are determined by the amount of the porosifying agent added, and the amount of the porosifying agent added is 0.1 to 200% by weight based on the polymerizable monomer. Is preferred. For use as various adsorbents and separating agents,
The pore diameter of the carrier is preferably 1 to 1000 nm. When the amount of the porosifying agent added is large, not only the resulting polymer becomes brittle, but also the exchange capacity per unit volume decreases, and a polymer having appropriate pore physical properties cannot be obtained. On the contrary, when the added amount is small, the pore diameter and the surface area tend to be small.

Further, when the content of the polyethylene monomer having two polymerizable double bonds is high, the resulting polymer tends to be porous depending on the porosifying agent added. is there. Whether or not the polymer has a porous structure can be simply judged as having a porous structure when the polymer is milky white or cloudy in appearance. For precise measurements, use the nitrogen adsorption method, mercury porosimetry method, or the like.

The hydrolysis and methylation of the present invention are carried out as follows. After obtaining the copolymer, the formamide group is hydrolyzed in an acidic or basic solution, more preferably in a basic solution. When carried out under acidic conditions, for example, as the acid,
Hydrochloric acid, sulfuric acid, phosphoric acid, etc. may be mentioned, and when hydrolysis is carried out under basic conditions, for example, lithium hydroxide, sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium methoxide, sodium ethoxide, etc. Can be used. The solution concentration varies depending on the reaction conditions, but is generally in the range of 0.1 N to 10 N, and more preferably 1 N to.
It is in the range of 3N. If the concentration of the acidic or basic solution is too high, it becomes difficult to handle the solution, which is not preferable for safety and hygiene. On the other hand, if the solution concentration is too low, the reaction rate of hydrolysis decreases, and formamide groups tend to remain. The reaction temperature is 50 to 150 ° C, and the reaction time is usually
It is preferably carried out for 1 to 10 hours.

When the formamide group is hydrolyzed, formic acid or its salt is produced. The amount produced is theoretically equivalent to the amount of amine produced. As an example, when the copolymer having an NVF content of 90% by weight is 100 ml (assuming the swelling degree of the polymer is 4 ml / g), the amount of formic acid produced is about 18.0 meq / g-polymer. It reaches 20.7g. Conveniently, in the present invention, formic acid produced as a by-product during the hydrolysis of the formamide group can be used in the subsequent methylation reaction.

The amine methylation reaction of this resin is generally a reaction using dimethyl sulfate and methyl halide. However, Esc using formic acid-formaldehydes
The hweiler-Clarke reaction (hereinafter abbreviated as “EC reaction”) is also known, and this EC reaction is a reaction in which a quaternary ammonium salt is not generated, that is, a strong base component is not generated at all, and thus a weak basic It was found to be very useful as a synthetic method for resins, and this reaction was adopted.

Degree of methylation by the EC reaction (hereinafter,
The "methylation degree") can be controlled to some extent by adjusting the charged amounts of formaldehyde and formic acid. Since the formic acid produced by hydrolysis is theoretically 1 gram equivalent to the amine, if the degree of methylation is 1.0 or more, that is, dimethylation, formic acid must be added separately.

It is already known that the optimum pH of the EC reaction is around 5 (PL L. Hanaff et al., Bul.
l. Soc. Chim. , 1989.1966).
However, also in the present invention, the optimum pH of the reaction is in the range of 3 to 7, more preferably 4 to 6. When the degree of methylation is 1.0 or less, after hydrolysis, the pH must be adjusted to the above optimum pH of the reaction solution with an acid or basic solution.

When carrying out the tertiary conversion of the amine, sodium formate is added when the formamide group is hydrolyzed under acidic conditions, and conversely, when the formamide group is hydrolyzed under basic conditions,
Formic acid must be added and acid or basic solution must be added as needed to adjust the pH. Formaldehydes are used as the carbon source of the methyl group used in the present invention. With formaldehyde, for example,
Formalin, paraformaldehyde, trioxane and the like are also preferably used. The reaction intermediates of EC reactions, imine (-CR = NH, R represents a hydrogen atom or a methyl group) or immonium salt ^{_{(-CR = NR 2 + · X}} -, R represents a hydrogen atom or a methyl group, X represents a coordinated ion). Therefore, it is not limited to formaldehyde as long as it is a carbon source that produces the above intermediate. As the reducing agent, formic acid or a salt thereof is preferably used, but it is not limited to formic acid as long as it can reduce the above reaction intermediate, and examples thereof include NaBH ₄ , NaBH ₃ CN, NaBH
₂ S _{3 and the} like are also included. The amount of addition is preferably 0 to 5 times the molar amount of the amine content.

The ion exchange capacity of the anion exchange resin produced by the above method is as follows. For example, as described above, the maximum ion exchange capacity of the polyvinylamine-based polymer ignoring the contribution of the crosslinking agent component to the unit weight (assuming the crosslinking agent content is 0%) is 2 in the case of the primary amine.
3.2 meq / g, when the substituent is a methyl group, the tertiary amine has 14.1 meq / g. This is because the exchange capacity per unit weight is 3.1 times that of the primary amine and 2.3 times that of the tertiary amine as compared with the styrene resin.

The ion exchange capacity in the present invention is
The weak base exchange capacity was measured according to the method described in the example and determined as the equivalent per dry resin. According to the present invention, a weakly basic anion exchange resin having a high ion exchange capacity, a high hydrophilicity and no organic chlorine compound and excellent chemical stability can be obtained. The weakly basic anion exchange resin obtained by the present invention is a chromatographic carrier, a membrane material,
It is also used as a carrier for catalysts, a polymer phase transfer catalyst, various adsorbents such as carriers for immobilizing enzymes, cells, and cells, a separating agent, and a carrier for immobilization.

[0030]

INDUSTRIAL APPLICABILITY The present invention provides a spherical base or porous weakly basic anion exchange resin having excellent chemical stability, high weak base exchange capacity, high hydrophilicity and no organic halogen compound. It provides a method of manufacturing reasonably.

[0031]

EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded. Example-1 Polymerization reaction: A 500 ml four-necked flask was charged with 200 ml of cyclohexane and 500 mg of ethyl cellulose to prepare a solution. On the other hand, N-vinylformamide (NV
F, purity 94%, impurities mainly formic acid 95 g, p-divinylbenzene (purity> 90%) 5.0 g, dimethyl sulfoxide 5 g, V-50 (azo polymerization initiator, Wako Pure Chemical Industries, Ltd.) 500 mg A solution was prepared. Both solutions were previously bubbled with N ₂ . The monomer solution prepared above was gradually added dropwise while stirring the cyclohexane solution at 100 rpm under N ₂ atmosphere. After stirring for 30 minutes to achieve distribution equilibrium, the temperature was raised and polymerization was carried out at 65 ° C. for 8 hours. At the time of polymerization, gelation occurred in about 15 minutes after the completion of heating. After completion of polymerization
The polymer was placed on a Buchner funnel and the polymer was washed with methanol to remove residual divinylbenzene, cyclohexane and the like. Subsequently, it was washed with water to remove NVF oligomers. The polymerization yield was 79%. The obtained polymer was white in appearance, but was slightly opaque when observed under a microscope.

Hydrolysis-methylation reaction: 500 ml of 100 ml of the above drained polymer and 100 ml of demineralized water
32 g of sodium hydroxide into the flask
Was added, and the initial NaOH aqueous solution concentration was set to 5 N, and the solution concentration at the end was set to 2.5 N-NaOH.
This was hydrolyzed at 90 ° C. for 3 hours. 50 ° C after reaction
After cooling to 27 g, formic acid (27 g) and 37% aqueous formaldehyde solution (81 g) were added. Further, hydrochloric acid was added to adjust the pH to 5. The temperature was gradually raised and the reaction was carried out at 90 ° C. for 3 hours. CO ₂ was generated violently in the initial stage, but at the end of the reaction, it hardly generated. After the completion of the reaction, the polymer was washed with water and subsequently made into an OH type with a 0.1N-NaOH aqueous solution. The polymer was washed again with water.

Ion exchange capacity measurement method: Polymer about 1
5 ml was packed in a column, and 2N-NaOH aqueous solution 500
ml was flushed with SV70, then washed with 1 liter of demineralized water to bring the counterion into the OH form. Accurately collecting 10.0 ml of this resin using a graduated cylinder, and filling the column. 250 ml of a 5% NaCl aqueous solution was poured into this and received in a measuring flask. This solution was titrated with acid and base to measure the strong base exchange capacity. 100 ml of 0.1 N HCl aqueous solution is flown into this column, the effluent is received in a measuring flask, and 50 ml of methanol is further flowed to wash the resin layer. Further, the liquid remaining in the resin layer was extruded by compressed air to collect these solutions. The solution was acid-base titrated. This measured the weak base exchange capacity. The exchange capacity per weight is
Separately, 10.0 ml of OH type resin was drained with a centrifuge, and the dry weight of the resin was measured and converted into ion exchange capacity per weight. As a result, the obtained polymer had a weak base exchange capacity of 9.3 meq / g and an average particle size of about 340 μm. The degree of methylation is determined by NMR ( ¹³ CCP / MAS method)
It was 1.8 from the area ratio measurement. Therefore, it was considered that 80% or more of the tertiary amine was contained in the anion exchange group.

Example-2 A tertiary reaction was carried out using the polymer after polymerization obtained in Example-1. Hydrolysis-methylation reaction: Drained polymer 1 above
00 ml and 50 ml of demineralized water were put in a 500 ml flask, 35 ml of 35% concentrated hydrochloric acid was put therein, and the initial solution concentration was set to 2.5N. It was hydrolyzed at 90 ° C. for 4 hours. After cooling to 50 ° C, sodium formate 4
0 g and 85 g of 37% aqueous formaldehyde solution were added. Aqueous sodium hydroxide solution was added dropwise to adjust the solution to pH 5. This was heated and reacted at 90 ° C. for 3 hours. CO ₂ was generated violently in the initial stage, but at the end of the reaction, it hardly generated. After the completion of the reaction, the polymer was washed with water and subsequently made into an OH type with a 0.1N-NaOH aqueous solution. The polymer was washed again with water. When the polymer was evaluated in the same manner as in Example-1, the obtained polymer had a weak base exchange capacity of 8.7 meq / g and an average particle size of about 340.
was μm.

Example 3 Polymerization reaction: NVF 90 g in a 500 ml eggplant flask.
(Purity 95%), Divinylbenzene (Purity 80%) 1
A solution of 0.0 g, acetone 90 g, and V-65 (azo polymerization initiator, manufactured by Wako Pure Chemical Industries, Ltd.) 300 mg was prepared. The monomer solution was bubbled with N ₂ to replace it. Polymerization is N ₂
It was performed at 70 ° C. for 7 hours in an atmosphere. During the polymerization, about 15 to 20 minutes after the completion of heating, the polymer turned cloudy and gelled.
After the polymerization was completed, the polymer was placed on a Buchner funnel. The polymer was washed with methanol and then with water. The polymerization yield was 92%. The obtained polymer was a white porous polymer. The polymer was ground to the proper size for better handling. The methylation reaction is described in Example-1.
I went the same way. When the polymer was evaluated in the same manner as in Example-1, the weak base exchange capacity of the obtained polymer was
The values were 9.7 meq / g and 3.00 meq / ml. The specific surface area of the porous body is 163 m ² / g, and the average pore size is 2
It was 7.4 nm and had a pore volume of 0.51 ml / g. The methylation degree was 1.76 as measured by the weight gain method. It was considered that 80% or more of the tertiary amine was contained in the anion exchange group.

Example-4 Polymerization reaction: the copolymer polymer (1 obtained in Example-1
Monomethylation reaction was performed using a primary amine polymer). Hydrolysis-methylation reaction: Drained polymer 1 above
00 ml and 100 ml of demineralized water were put into a 500 ml flask, and 26 g of sodium hydroxide was put therein, the initial hydrochloric acid solution concentration was 3.8 N, and the final concentration was 1.5 N-.
It was set to be NaOH. It was hydrolyzed at 90 ° C. for 3 hours. After the reaction was completed, the mixture was cooled to 50 ° C. and formic acid 10 g, 3
38 g of 7% aqueous formaldehyde solution was added. Furthermore,
Hydrochloric acid was added to adjust the pH to 5. The temperature was gradually raised and the reaction was carried out at 90 ° C. for 3 hours. CO ₂ was generated violently in the initial stage, but at the end of the reaction, it hardly generated. After completion of the reaction, the polymer was washed with water and then 0.1N-
It was made OH type with an aqueous NaOH solution. The polymer was washed again with water. When the polymer was evaluated in the same manner as in Example-1, the weak base exchange capacity of the obtained polymer was 13.7 me.
It was q / g and the average particle size was about 340 μm. The degree of methylation was 1.16 as measured by the weight gain method.

Claims (1)

[Claims] 1. A formamide group is obtained by copolymerizing a solution containing N-vinylformamide and a polyethylene monomer in the presence of a polymerization initiator, and treating the resulting copolymer under acid or basic conditions. Is hydrolyzed to an amino group, and then formaldehyde and optionally formic acid or a salt thereof are added and reacted to methylate the amino group, which is a method for producing a weakly basic anion exchange resin.