JPS63130605A - Production of anion exchanger - Google Patents

Abstract

PURPOSE:To produce an anion exchanger excellent in anion exchange capacity and hydrophilicity, by copolymerizing a vinyl monomer having an anion exchange group with a specified divinyl monomer in the presence of a radical polymerization initiator. CONSTITUTION:A vinyl monomer (A) having an anion exchange group (e.g., vinylpyridine) is copolymerized with 1-4,000pts.wt., per pt.wt. component A, divinyl monomer (B) having a linear polyether group [e.g., a divinyl polyether of the formula (wherein n is 3-150) and, optionally, 0.1-3pts.wt., per pt.wt. component B, other monomers (C) (e.g., styrene) at 60-120 deg.C for 30min-20hr to obtain an anion exchanger having an ion exchange capacity of 0.001-2meq/g (dry weight), having an IR absorption at 1,100cm<-1> assignable to a linear polyether and a molar degree of crosslinking of 0.1-99.9%.

Description

[Detailed description of the invention] The present invention relates to a novel method for producing an anion exchanger.

Conventionally, common ion exchangers include a styrene-divinylbenzene copolymer into which an ion exchange group is introduced, or a copolymer of a vinyl monomer and divinylbenzene having an ion exchange group. The exchange capacity of these ion exchangers is usually 2 to 3 meq/JF (dry body), and for example, the exchange capacity of a cation exchanger for ion chromatography is about 0.02 meq/11 (dry body).

However, such an ion exchanger having a small ion exchange capacity has various drawbacks h1 in its manufacturing method. That is, when producing an ion exchanger with a small ion exchange capacity, it is difficult to uniformly introduce ion exchange groups onto the surface of the styrene-divinylbenzene copolymer and to control the ion exchange capacity. Introducing the ion exchange group requires a complicated process. On the other hand, in the case of a copolymer of a monomer having an ion exchange group and divinylbenzene, if the ion exchange capacity is small, the copolymer is poor in hydrophilicity, and therefore cannot exhibit sufficient ion exchange ability. In addition, as an anion exchanger with a small ion exchange capacity, a styrene-divinylbenzene cation exchanger,
An anion exchanger that electrostatically adsorbs a finer anion exchanger than the cation exchanger has been proposed (Analyt
ical Chemist, rv vol 47゜4
11.1975). However, this anion exchanger. Influence of H 2: Because the adsorbed anion exchanger is easily peeled off due to mechanical influence, sufficient anion exchange ability cannot be expressed.

As a result of intensive research by the present inventors to solve the above drawbacks,
The present inventors have discovered that a desired anion exchanger can be obtained by specifically using a divinyl monomer having a linear polyether group as a crosslinking agent, and have completed the present invention.

The present invention provides a method for producing an anion exchanger by copolymerizing a monomer mixture containing a vinyl monomer having an anion exchange group and a divinyl monomer having a linear polyether group in the presence of a radical polymerization initiator. It is.

It is essential that the anion exchanger obtained in the present invention has an anion exchange group in the molecule. The ion exchange group and ion exchange capacity can be confirmed, for example, by the method described below,
Generally, the ion exchange capacity is 0.001 to 2 meq/,
! Those in the range of i' (dry body) h'' - are preferably used. Generally, the water content of the ion exchanger is 5 to 500%.
Preferably, the range is . The ion exchange group is not particularly limited, but anion exchange groups such as primary, secondary or tertiary amino groups; quaternary ammonium bases are generally suitable.

Further, the anion exchanger obtained in the present invention has a 1100 c
It has an infrared absorption band at m-'. This infrared absorption band is recognized to be based on linear polyether groups from the raw materials described below. The infrared absorption band has a peak at 1,100 cm-1, and the peak at 1,100 cm-' is based on the linear polyether. Although the infrared absorption band at 1100 cm-' may be slightly shifted depending on the shape, structure, etc. of the linear polyether group, it can generally be clearly identified as a linear polyether group. The composition, shape, etc. of the polyether group differ depending on the raw material, but
It is not particularly limited as long as it is linear.

In general, an oxyethylene group, that is, a linear polyether group represented by the general formula 1←0CH2CH,,→- (however, n is preferably 3 to 150) is preferred, and both ends or one end of the above general formula are hydrocarbon residues, carbon It may also be in the form of a bond with an acid residue. In addition, the number of oxyethylene groups mentioned above is large (I see, it is preferable because it imparts hydrophilicity, but if it is too large, the mechanical strength tends to decrease, so the number is generally 3 to 150, preferably 10 to 20. .

Furthermore, the anion exchanger obtained in the present invention has a crosslinked structure. The crosslinked structure is not particularly limited, but it is generally preferable to select a molar crosslinked layer in the range of 1 to 99.9%.The anion exchanger of the present invention has a crosslinked structure. Therefore, it has the property of being insoluble and infusible. Therefore, the presence or absence of a crosslinked structure can be confirmed by confirming that the anion exchanger of the present invention is insoluble and infusible.

As explained above, the anion exchanger that cannot be obtained in the present invention has an anion exchange group in the molecule, has an infrared absorption band at 1100 cm-' based on a linear polyether, and has a crosslinked structure. It is an insoluble and infusible anion exchanger with The ion exchanger obtained by the present invention exhibits excellent performance and is used in fields conventionally known as ion exchangers. In particular, in the present invention, not only can the ion exchange capacity be controlled extremely easily, but even an ion exchanger with a small ion exchange capacity has good hydrophilicity, so that the ion exchange capacity is fully exhibited. It also has advantages.

The anion exchanger in the present invention is produced by copolymerizing a monomer mixture of a vinyl monomer having an anion exchange group and a divinyl monomer having a linear polyether group in the presence of a radical polymerization initiator. .

Furthermore, the anion exchanger of the present invention can be produced by simultaneously using the above monomer mixture and a copolymerizable monomer, if necessary.

The vinyl monomer having an anion exchange group is not particularly limited, but generally includes vinylpyridine,
Vinylaniline, vinylbenzylamine, derivatives thereof, etc. are used.

The divinyl monomer having a linear polyether group used in the present invention is not particularly limited and any publicly known divinyl monomer can be used. Polyether dimethacrylates represented by n=3 to 25) are preferably used.

In addition, monomers that can be copolymerized with the above monomers include:
Monomers commonly used as raw materials for producing ion exchange membranes, such as styrene, ethylvinylbenzene, and chloromethylstyrene.

Acrylonitrile, divinylbenzene, etc. are preferably used.

The combination of the above-mentioned monomers depends on the desired properties of the desired anion exchanger and cannot be determined unconditionally.

However, the anion exchanger obtained by copolymerizing the two-component monomer of the present invention, a vinyl monomer having an anion exchange group and a divinyl monomer having a linear polyether group, generally has a small ion exchange capacity. It also has extremely good hydrophilicity. Furthermore, the strength of the anion exchanger can be controlled by adding a copolymerizable monomer. Therefore, the charging ratio of each monomer may be determined by taking into consideration the properties of the intended anion exchanger, such as strength, degree of crosslinking, amount of ion exchange groups, etc.

In general, divinyl monomers with linear polyether groups have 1
The copolymerizable vinyl monomer is preferably used in an amount of 0.1 to 6 times (by weight) relative to the divinyl monomer having a linear polyether group.

The exchange capacity of the anion exchanger obtained by the present invention is:
Since it almost matches the value calculated from the composition ratio of raw materials, it is extremely easy to control the ion exchange capacity. Therefore, by adjusting the composition ratio of the raw material monomer mixture,
It is possible to easily control a wide range of ion exchange capacities such as (dry body), and to obtain an anion exchanger that is hydrophilic and exhibits sufficient ion exchange ability even at low exchange capacities.

For the production of the anion exchanger in the present invention, a method in which the above monomer mixture is generally subjected to button polymerization in the presence of a radical polymerization initiator is suitably employed. The radical polymerization initiator is not particularly limited, and known ones can be used. A typical example is benzoyl peroxide.

Acetyl peroxide, di-tert-butyl peroxide.

Peroxides such as coumesohydroberoxide, p-bromobenzenediazonium hydroxide, triphenylmethylazobenzene, azo compounds such as αα′αboobisisobutyronitrile, N-nitronacylanilide, tetraphenylfuccinonitrile, etc. is suitable.

The amount of these radical polymerization initiators added is generally 0.1% by weight based on the monomer mixture.

Furthermore, the polymerization method in the present invention is carried out according to conventionally known manufacturing methods depending on the form of the anion exchanger to be manufactured. Generally, bulk polymerization and solution polymerization methods are preferably employed. When the raw material monomer mixtures are mutually soluble, it is not necessary to use a solvent. If the raw material monomer mixtures do not dissolve in each other, a solvent that dissolves the monomers is selected and used.

Examples of such solvents include alpha alcohols such as methanol, ethanol and butanol, ketones such as acetone and ethyl methyl ketone, ethylene glycol and diethylene glycol.

Glycols such as diethylene glycol monomethyl ether, glymes, acetonitrile, acetic acid, water, etc. are used.

Since the polymerization conditions vary depending on the type and composition ratio of the 7-mer mixture, the type of radical polymerization initiator, etc., they cannot be determined generally, but are generally carried out at a temperature of 60 to 120°C for 30 minutes to
20 hours is most preferably employed.

EXAMPLES In order to explain the present invention more specifically, the present invention will be described below with reference to Examples, but the present invention is not limited to these Examples. The properties of the ion exchangers shown in the Examples were measured by the following method.

(1) Anion exchange capacity: First, add 0.5
N-NaC4 and 1. The sample was alternately immersed in an ON-NaNO3 aqueous solution several times, then immersed again in 0.5 N-NaCL, and then Donnan-adsorbed NaCL was thoroughly washed and removed using ion-exchanged water. Next, this is packed into a column, and 1
．． ON - ct- released by flowing down 0 g of NaN aqueous solution
The amount (M meq 1) was determined by a silver nitrate titration method using a 0.1 M silver nitrate aqueous solution.
It was returned to the Cr form with N-NaCA, thoroughly washed with water, and vacuum dried at 60°C day and night.The weight (Wg) was measured, and the anion exchange capacity was calculated according to the following formula.

Anion exchange capacity (c) = M/W (meq / 11
- Dry resin) (2) Mechanical strength A glass column with a diameter of 16 nm is filled with 5 g of an ion exchange resin with a particle size of 42 to 145 mesh, and a differential pressure of 50 α in water column is applied to flow water, and the flow rate at that time is V. ,) (cc/
min ) was measured.

Then I N -HC1 aqueous solution, H2O, 0,5N-N
These aCt aqueous solutions were repeatedly flowed down in the order of 10 times at a differential pressure of 50 (7) (water columns). After that, the water column was 50 again.
Water outflow velocity Vt (cc/min
) and the initial outflow velocity V. Ratio (■o/vt)
This was taken as a measure of mechanical strength. That is, it was determined that the closer v0/vt was to 1, the higher the mechanical strength.

(3) Water content: The ion exchange resin was immersed in water for a day and night, and then the surface of the resin was wiped with paper and its weight (W) was measured. Next, this resin was dried at 60°C under vacuum.
The weight (W2) was measured, and the water-containing weight was calculated using the following formula.

(4) Degree of Crosslinking The degree of crosslinking was calculated using the following formula, where the number of moles of all the monomers to be charged is Ml, and the number of moles of divinyl monomer is 0, M2.

Example 1 After a glass reactor with an internal volume of 100 mm equipped with a reflux condenser and a stirrer was sufficiently purged with nitrogen, divinyl polyether (n = 13 to 14) 10.011.0, 1)-vinylbenzyl Trimethylammonium chloride (purity 9
0%) 1464, α,α'-azobisinbutyronitrile was added at 0.5 wt% based on the total monomers, and diethylene glycol monomethyl ether 10-1 water 1 m
g and stirred thoroughly until all monomers were dissolved and mixed. Thereafter, the mixture was reacted for 18 hours at a reaction temperature of 60° C. while stirring, resulting in a lumpy resin. Next, this resin was transferred to a glass filter, washed with methanol and water, filtered, dried under reduced pressure at 60 DEG C. overnight, and its weight was determined to be 8.29. Next, crush this resin with a crusher,
A resin of 42 to 145 meshes was obtained. The anion exchange capacity 6 mechanical strength and water content of this resin were measured according to the measurement method described above, and the results were as follows.

Anion exchange capacity: 0.05 meq/111-dry resin (measured value) 0.061 meq/1.9-dry resin (calculated value) Mechanical strength: 1.01 Moisture content: 36% Molar crosslinking degree: 95 % Example 2 Using the same reactor as in Example 1, divinyl polyether (n=13-14) 10.0,9.4-vinylpyridine 180η, α, α′-azobisin butyronitrile was prepared. 0.5 wt% based on all the monomers was added, 5-1 methanol and 1-1 water were added, and the mixture was sufficiently stirred until all the monomers were dissolved and mixed. Thereafter, the mixture was reacted for 18 hours at a reaction temperature of 60° C. with stirring, resulting in a lumpy resin. Next, this resin was transferred to a glass filter, washed with methanol and water, filtered, dried under reduced pressure at 60° C. for 1 night, and its weight was measured, and it was found to be 9.6.9. Further, this resin was placed in a flask with an internal capacity of 100 mm, and 50 mm of a 20% methanol solution of methyl iodide was added thereto to quaternize the pyridine groups at room temperature in a nitrogen atmosphere for 24 hours. Next, this resin was transferred to a glass filter, washed with methanol and water, filtered, dried under reduced pressure at 60 DEG C. overnight, and weighed, which was 9.8 g. Next, this resin was pulverized using a pulverizer to obtain a resin having 42 to 145 meshes. The anion exchange capacity, mechanical strength, and water content of this resin were measured according to the measurement methods described above, and the results were as follows.

Anion exchange capacity: 0.15 meq/1 g - dry resin (measured value) 0.167 meq/IJi' - dry resin (calculated value) Mechanical strength: 1.02 Moisture content - 68% Molar degree of crosslinking = 88%

Claims (1)

[Claims] Anion exchange characterized by copolymerizing a monomer mixture containing a vinyl monomer having an anion exchange group and a divinyl monomer having a linear polyether group in the presence of a radical polymerization initiator. How the body is manufactured.