JPH0826106B2 - Method for producing base resin of ion exchange resin or chelate resin - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Field of Industrial Application> The present invention relates to a method for producing a base resin (hereinafter referred to as a resin) of an ion exchange resin or a chelate resin. More specifically, it relates to a method for producing a resin having a reduced swelling / shrinkage ratio by mixing rubber into the resin.

<Prior Art> What is important in performing water treatment or the like using an ion exchange resin or a chelate resin is selective ion exchange or adsorption (hereinafter, typically referred to as adsorption) with respect to a target component. In addition, the elution and regeneration are easy, and the ion exchange rate or the adsorption rate (hereinafter, typically referred to as the adsorption rate) is fast. In addition to this, for example, the particle size is large and the particle size is uniform. And that the swelling / shrinkage rate is small.

Contact between the ion exchange resin or chelate resin and the liquid to be treated is generally carried out by passing the liquid to be treated through a column filled with the resin. If the swelling / shrinking ratio is large, the packed column must be made large, which increases the cost of the equipment, and also causes the resin to break due to repeated swelling / shrinking,
There is an inconvenience that it is consolidated and the pressure loss at the time of passing the liquid becomes large.

The adsorbability of the target component varies depending on the type of functional group to be provided, but the adsorption rate, swelling / shrinkage rate, etc. differ depending on the physical properties of the base resin such as the ion exchange resin or the chelate resin.

In order to synthesize a base resin suitable as an ion exchange resin or a chelate resin, various monomers and various polymerization methods have been proposed.

In order to reduce the swelling / shrinkage rate, generally, a method of increasing the amount of a monomer having two or more ethylene bonds in the molecule is used.

(Honda, Kakihana, Yoshino, "Ion exchange resin-basic operation and application-" P11-12, published by Hirokawa Shoten in 1955) <Problems to be solved by the invention> However, in the known method, when introducing a functional group The reactivity decreases, the amount of ion exchange or adsorption of the target component significantly decreases, or the ion exchange or adsorption rate becomes slow. Further, since the amount of the monomer having two or more ethylene bonds in the expensive molecule is increased, there is a disadvantage that the price of the ion exchange resin or the chelate resin is increased.

In view of such circumstances, the present inventors have earnestly studied to develop a resin that has a small swelling / shrinkage ratio and does not deteriorate the adsorption performance. As a result, by polymerizing a monomer in the presence of rubber, the rubber in the resin substrate is It has been found that the swelling / shrinkage ratio is reduced by mixing the admixture with the adsorbent performance, and thus the present invention has been completed.

<Means for Solving the Problem> That is, in the present invention, a mixture of a monomer having one ethylene bond in the molecule, a monomer having two or more ethylene bonds in the molecule and a rubber is used as an aqueous medium. It is a method for producing a base resin of an ion exchange resin or a chelate resin which undergoes suspension polymerization in a medium.

Examples of the monomer having one ethylene bond in the molecule used in the present invention (hereinafter referred to as main monomer) include, for example, styrene, methylstyrene, ethylstyrene, chlorostyrene, aminostyrene, cyanostyrene, etc. Styrene compounds; acrylonitrile, methacrylonitrile,
α-chloroacrylonitrile, vinylidene cyanide, crotonnitrile, 2-cyanoethyl acrylate, 2-
Nitrile compounds such as cyanoethyl methacrylate; acrylic acid compounds such as acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate; methacrylic acid compounds such as methacrylic acid, methyl methacrylate, glycidyl methacrylate; N-vinylphthalimide, vinyl imidazole , Heterocyclic vinyl compounds such as vinyl pyridine, and the like.

The swelling / shrinkage rate of the resin is generally particularly large when a polymer of a hydrophilic monomer such as acrylic acid or methacrylic acid is used.

When the monomer has a functional group as an ion exchange resin or a chelate resin, it is used as it is as an ion exchange resin or a chelate resin after polymerization, but when it does not have a functional group, it is functionalized after polymerization. A process for imparting a group is required.

Further, in order to improve the resin strength and the swelling / shrinkage property, a monomer having two or more ethylene bonds in a molecule capable of being copolymerized with the main monomer (hereinafter referred to as a crosslinkable monomer). ) Is used.

As the crosslinkable monomer, for example, divinylbenzene, trivinylbenzene, divinyltoluene, divinyl ketone, diallyl phthalate, diallyl maleate, N,
Examples thereof include N'-methylenebisacrylamide, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate and the like.

The use ratio of the crosslinkable monomer is not particularly limited, but it is generally used in the range of 2 to 40% by weight based on all the monomers.

The rubber used in the method of the present invention is a rubber that is easily reacted with a main monomer and / or a crosslinkable monomer by a radical generated by a radical initiator such as azobisisobutyronitrile or benzoyl peroxide, or by heat. It is not particularly limited as long as it is, but generally, styrene-butadiene rubber, butadiene rubber, alfin rubber, isoprene rubber, isobutylene-isoprene rubber, acrylonitrile-butadiene rubber, acrylonitrile-isoprene rubber, butyl rubber, acrylonitrile-butyl rubber, ethylene. -Propylene-diene monomer Diene-based rubber such as ternary copolymer and olefin-based rubber may be mentioned.

The ratio of the rubber used varies depending on the ratio of the crosslinkable monomer used, but it is generally used in the range of 2 to 40% by weight based on the total monomers.

If the usage ratio exceeds 40% by weight, the hydrophobicity of the resin becomes high, the amount of the target component adsorbed decreases, and the adsorption rate becomes slow, which is not preferable. Even if the usage ratio is less than 2% by weight, it can be used but the effect is small. In order to have the characteristics as a resin and to improve the swelling / shrinkability,
It is preferably used in the range of 5 to 30% by weight.

The reason why the swelling / shrinkage ratio of the resin obtained by polymerizing the main monomer and the crosslinkable monomer in the presence of rubber is small is not clear, but a part of the mixed rubber is the main monomer and / or the crosslinkability. It is thought that this is because it reacts with the monomers and they become crosslinked to become elastic, thereby absorbing the swelling contraction.

As the polymerization method, a method is generally used in which a mixture of a main monomer, a crosslinkable monomer and a rubber is suspension-polymerized in an aqueous medium to obtain a spherical polymer suitable as a resin.

The rubber is usually powdery or granular before vulcanization, and it can be added to a polymerization system and polymerized in a dispersed state, but in general, rubber is the main monomer and a crosslinkable monomer. After dissolving in the body or by using an organic solvent, the rubber, the main monomer and the crosslinkable monomer are dissolved in the organic solvent and then polymerized.

Examples of the organic solvent used include aromatic hydrocarbons such as toluene and xylene; halogenated hydrocarbons such as carbon tetrachloride, trichloroethane, trichloroethylene, chlorobenzene and dichlorobenzene.

The amount of the organic solvent used is generally in the range of 20 to 200% by weight based on the total amount of the monomers.

In suspension polymerization, the total monomer / water ratio for obtaining a good dispersion state is generally in the range of 1/1 to 1/10 by volume.

Also, suspension stabilizers are commonly used to obtain spherical polymers.

As the suspension stabilizer, water-soluble polymer compounds such as polyvinyl alcohol, hydroxyalkyl cellulose, starch, gelatin, polyacrylic acid, sodium dodecylbenzene sulfonate; barium sulfate, calcium carbonate,
Hydroxyapatite, water-insoluble inorganic compounds such as bentonite and the like, the effect is the type of monomer used,
Since it varies depending on the type of organic solvent, polymerization conditions, etc., preliminary experiments can be appropriately conducted and set.

The ratio of the suspension stabilizer used affects the particle size of the polymer to be obtained, and therefore varies depending on the type of monomer, the type of suspension stabilizer, etc. Used in the range of%.

Any polymerization catalyst can be used without particular limitation as long as it is an oil-soluble catalyst.

Such oil-soluble catalysts include azo compounds such as azobisisobutyronitrile and azobisisovaleronitrile:
Examples thereof include organic peroxides such as diisopropyl peroxydicarbonate, lauroyl peroxide, benzoyl peroxide, t-butyl peroxybenzoate, and t-butyl peroxide, and these may be used alone or in combination as necessary. it can.

The amount of the catalyst used is not particularly limited, but is usually added in a proportion of 0.01 to 3% by weight based on the total charged monomers.

The polymerization reaction is carried out on rubber, main monomer, crosslinkable monomer and / or
Alternatively, a solvent, a polymerization stabilizer, and a polymerization catalyst are charged into a polymerization tank with stirring or without stirring, and then, as they are, or after removing oxygen in the reaction system as necessary, under normal pressure or pressure,
Polymerization is carried out at a predetermined temperature for a predetermined time with stirring.

The stirring speed is not particularly limited, but since it greatly affects the particle size of the polymer to be obtained, it may be determined by conducting preliminary experiments as appropriate according to the type of monomer, suspension stabilizer, amount used, type of polymerization tank, etc. Is good.

The polymerization temperature may be selected at a temperature corresponding to the decomposition temperature of the polymerization catalyst, but a range of 50 ° C to 150 ° C is generally used.

After completion of the polymerization, when an organic solvent is used, the solvent is removed by subjecting it to an operation such as distillation.

As described above, the polymer thus produced can be used as it is, or after being washed and dried, as a base resin of an ion exchange resin or a chelate resin.

<Effects of the Invention> The ion exchange resin or chelate resin produced by using the base resin obtained by the present invention has a smaller swelling / shrinkage ratio and a stronger physical strength than conventional ion exchange resins or chelate resins. Its industrial value is extremely high, such as little destruction.

<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.

Comparative Example 1 1150 parts by weight of water in which 0.1 part by weight of hydroxymethyl cellulose was dissolved was placed in a 2 liter cylindrical flask equipped with a reflux condenser, a nitrogen introduction tube, a stainless steel three-blade stirrer and a thermometer, and 11.5 parts by weight of sodium sulfate. Then, add 300 parts by weight of acrylonitrile, 26 parts by weight of divinylbenzene with a purity of 56% (including 44% of ethylvinylbenzene), 198 parts by weight of toluene and 3.3 parts by weight of lauroyl peroxide, and add nitrogen. It was stirred for 30 minutes while flowing. Then, the temperature was raised to 60 ° C., the reaction was carried out for 2 hours, and the polymerization was further conducted at 70 ° C. for 2 hours and at 80 ° C. for 2 hours. After the reaction, toluene was distilled to obtain a polymer. (Hereinafter, this polymer is referred to as "resin A.") 30 g of dried resin A is then added to 300 ml of a methanol solution having a hydroxylamine concentration of 10% at 60 ° C.
The reaction was carried out for 7 hours to produce a chelate resin having an amidoxime group.

Chelate resin 0.5 g 460 mg-Cu ²⁺ / l pH 4.8 solution 50
When the mixture was charged into a ml and stirred and adsorbed for 3 hours, the copper adsorption amount of this chelate resin was 37.1 mg / g resin.

Further, after 50 ml of the chelate resin was immersed in 250 ml of 2N-NaOH aqueous solution for 2 hours, the resin was separated by filtration and washed with water. Then 2N-HCl
After dipping in 250 ml of an aqueous solution for 2 hours, the resin was filtered off and washed with water.

This operation was repeated twice, and the resin volume when immersed in a 2N-NaOH and 2N-HCl aqueous solution was measured. Was 1.84.

Examples 1 to 5 Resins B to F were prepared in the same manner as in Comparative Example 1 except that the monomers and rubbers shown in Table 1 were used instead of acrylonitrile.
I got Then, resins B to F were treated in the same manner as in Comparative Example 1,
A chelating resin having an amidoxime group was produced. The amount of Cu adsorbed and the swelling ratio of this chelate resin were measured in the same manner as in Comparative Example 1. The results are shown in Table 2.

Example 6. Comparative example 2 Polymerization was carried out in the same manner as in Comparative example 1 except that the monomers and rubbers shown in Table 1 were used instead of acrylonitrile, and chelate resins having a pyridine ring (resins G and H). Got

The amount of Cr ⁶⁺ adsorbed and the swelling ratio were measured in the same manner as in Comparative Example 1 except that a solution of pH 3.2 containing these resins G and H and 500 mg-Cr ⁶⁺ / l was used. The results are shown in Table 3.

Example 7 Comparative Example 3 Resins I and J were obtained in the same manner as in Comparative Example 1 except that the monomers and rubbers shown in Table 1 were used instead of acrylonitrile. 50 g of the dried resin of Resins I and J was heated in 1 N alcoholic potassium solution 1 under reflux for 20 hours for hydrolysis to synthesize a weakly acidic cation exchange resin.

Known methods for the obtained weakly acidic cation exchange resin (Miyahara, Omagari, Sakai, "Practical ion exchange" p167-17
4 47, published by Kagaku Kogyo Co., Ltd.), the total exchange capacity and swelling rate were measured.

 The results are shown in Table 4.

Example 8 Comparative Example 4 Resins K and L were obtained in the same manner as in Comparative Example 1 except that the monomers and rubbers shown in Table 1 were used instead of acrylonitrile and polyvinyl alcohol was used instead of hydroxymethyl cellulose. . After 50 g (dry) of the resins K and L was put into 50 ml of tetrachloroethylene and allowed to swell, 100 g of chloromethyl ether and 25 g of anhydrous zinc chloride were added, and the reaction was carried out at 55 ° C. for 5 hours. After the reaction, the entire amount of the product was put into 2.5 l of cold water to decompose excess chloromethyl ether.

The obtained chloromethylated resin was treated with diethylenetriamine.
A weakly basic ion exchange resin was obtained by reacting with 400 g at 140 ° C. for 4 hours. The total exchange capacity and swelling rate of the obtained weakly basic ion exchange resin were measured. The results are shown in Table 5.

Example 9 Comparative Example 5 100 ml of the weakly basic anion exchange resin obtained in Example 8 and Comparative Example 4 was packed in a vinyl chloride column having an inner diameter of 25 mm, and a 2N-HCl aqueous solution was added for 5 minutes in a downward flow and water 15 Minute 2N-NaOH aqueous solution 5
The solution was passed through SV = 10 Hr ⁻¹ in the order of minute and water for 15 minutes.

After 200 cycles, take out the resin and observe it with a microscope.
When the ratio of the spherical resin to the destroyed resin was calculated, it was 6
The results shown in the table were obtained.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroaki Hata 5-1 Sokai-cho, Niihama-shi, Ehime Sumitomo Chemical Co., Ltd. (56) References JP-B-38-24595 (JP, B1)

Claims (6)

[Claims] 1. An ion exchange resin for suspension-polymerizing a mixture of a monomer having one ethylene bond in the molecule, a monomer having two or more ethylene bonds in the molecule and a rubber in an aqueous medium. A method for producing a chelate resin base resin. 2. A compound having at least one ethylene bond in the molecule thereof selected from the group consisting of styrene compounds, nitrile compounds, acrylic acid compounds, methacrylic acid compounds and heterocyclic vinyl compounds. The method for producing a base resin according to claim 1, wherein 3. A monomer having two or more ethylene bonds in the molecule is divinylbenzene, trivinylbenzene, divinyltoluene, divinylketone, diallyl phthalate, diallyl maleate, N, N'-methylenebisacrylamide, Claim 1 which is at least one compound selected from the group consisting of ethylene glycol dimethacrylate and polyethylene glycol dimethacrylate.
A method for producing a base resin according to item. 4. The rubber is styrene-butadiene rubber, butadiene rubber, alfin rubber, isoprene rubber, isobutylene-isoprene rubber, acrylonitrile-butadiene rubber, acrylonitrile-isoprene rubber, butyl rubber, acrylonitrile-butyl rubber, ternary ethylene-propylene-diene monomer. The method for producing a base resin according to claim 1, wherein the rubber is at least one rubber selected from the group consisting of copolymers. 5. The method for producing a base resin according to claim 1, wherein the amount of the monomer having two or more ethylene bonds in the molecule is 2 to 40% by weight based on all the monomers. . 6. The method for producing a base resin according to claim 1, wherein the amount of rubber is 2 to 40% by weight based on all the monomers.