JPH01281151A - Production of cation-exchange resin - Google Patents

Abstract

PURPOSE:To produce an inseparable and stable cation-exchange resin by coating the surface of a base material with an anion-exchange latex retained thereon with a cross linking polymer reactive therewith and fixing said anion-exchange latex thereto. CONSTITUTION:In a cation-exchange resin for use in a high-speed liquid chromatography, a base material 1 is a cross-linking polymeric gel, on whose surface a resin such as polyhydroxylalkylmethacrylate which has halogen group and hydroxyl group or into which they are capable of being introduced is formed. This gel is then diffused in an organic solvent and stirred while a suspension of polystyrene ion-exchange latex 2 is being added thereto gradually. The resulting slurry is thereafter mixed with a fixed polymeric layer 3 such as multifunctional epoxy compound and a reaction initiation catalyst is finally added thereto bring about reaction at a predetermined temperature for a predetermined time, whereby a cation-exchange resin from which an anion-exchange latex is inseparable can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for producing a latex type (vellicular type) cation exchange resin in which ion exchange latex is chemically retained on the surface of a base material.

<Prior art> Ion exchange resins used in high performance liquid chromatographs (e.g. ion chromatographs) have a fairly small specific ion exchange capacity I compared to the ion exchange resin in the membrane. Made of resin (approx. 1710 to 17500). The manufacturing method of such an ion exchange resin having a low ion exchange capacity is very different from that of general ion exchange resins and is a special manufacturing method, and the manufacturing method is broadly classified into two types. That is, the first manufacturing method uses a resin as a base material (this resin itself is often a filler for chromatography).
This is a so-called latex-type ion-exchange resin manufacturing method that creates a resin with a low ion-exchange capacity by retaining extremely small ion-exchange latex on the surface of the resin. This is a so-called chemical bonding type ion exchange resin production method in which ion exchange groups are directly introduced chemically to produce a resin with a low ion exchange capacity. On the other hand, in ion chromatographs, especially subrest type ion chromatographs, latex type ion exchange resins are most commonly used, while chemically bonded ion exchange resins are mainly used in non-subrest type ion chromatographs, and suppressed ion chromatographs. There are almost no commercially available graphs. Latex-type ion exchange resins are made of polystyrene gel or sulfonated polystyrene gel as a base material, and are made of cation exchange latex with a physical particle size of about 0.01 to 0.1 μm using electrostatic adsorption or a glue called a binder on the surface. is maintained. This type of ion exchange resin has ion exchange groups present in high density only on the surface of the resin, so it has the advantage of very rapid separation equilibrium and high separation performance.

However, since latex-type ion exchange resins are not fillers in which the latex and base material, which have ion exchange groups, are strictly integrated, there is a possibility that the ion exchange latex may be desorbed depending on the usage conditions, reducing the separation ability. It has the disadvantage of being expensive. That is, for example, in the electrostatic adsorption type, there is a risk of desorption due to sudden changes in the ionic strength in the mobile phase or sample.
In the physical adsorption type, there is a risk of desorption due to contamination with an organic solvent or mechanical load.

<Problems to be solved by the invention> However, chemically bonded fillers (ion-exchange resins) have various features that latex-type fillers (ion-exchange resins) do not have, and are superior to latex-type fillers in terms of performance. However, it is not necessarily possible to replace latex-type fillers in terms of separation performance and separation characteristics.9 For example, regarding the stability of ion-exchange groups, hydrophilic chemically bonded fillers Ion exchange resins, which are polystyrene-based and are used in general latex-type fillers, are superior to fillers. In addition, any latex-type filler can be used as long as it does not adversely affect separation, so it is easy to improve it to a hard and high-pressure-resistant filler in order to increase speed. In the case of fillers, it is generally difficult to improve them into hard and highly pressure-resistant fillers. Because latex-type fillers have these advantages, it is thought that latex-type fillers will continue to be mainstream in the future, but for this reason, it is necessary to create a filler that does not release latex. Cation exchange! ! A method for manufacturing fingers was strongly desired.

The present invention has been made in view of this situation, and its purpose is to provide a method for producing a latex-type cation exchange resin suitable for use in ion chromatographs and the like without desorption of ion exchange latex. There is a particular thing.

Specific Means for Solving the Problems> The features of the present invention that solve the above problems are that the cation exchange resins used in high performance liquid chromatographs etc. are It is manufactured using the same process.

(a) Hydroxyl group or halogen group depending on the reaction method.

Or the process of preparing a polymer gel with epoxy groups.

(b) A step of dispersing the polymer gel in a small amount of an organic solvent, and then dispersing the ion exchange latex in the organic solvent.

(c) A step of gradually adding and stirring the ion exchange latex suspension to the polymer gel slurry, and then mixing a polyfunctional epoxy compound to form the fixed polymer layer with the slurry.

(d) A step in which a reaction initiation catalyst is added and the reaction is carried out at a constant temperature for a certain period of time.

(e) Wash with an organic solvent and then thoroughly with water, and then
The process of exchanging to the desired positive ion.

<Example> Hereinafter, the present invention will be explained in detail using the drawings. 1st
The figure is a process explanatory diagram illustrating a method for producing a cation exchange resin according to the present invention. In this figure, first, a polymer gel having hydroxyl groups, halogen groups, or epoxy groups is prepared depending on the reaction method. Next, the polymer gel (resin) is dispersed in a small amount of an organic solvent. Thereafter, the ion exchange latex is dispersed in an organic solvent. Next, the suspension of the ion exchange latex is gradually added to the slurry of the polymer gel (resin) and stirred. Thereafter, a polyfunctional epoxy compound that will become a fixed polymer layer is mixed into the slurry. Finally, a reaction initiation catalyst is added and the mixture is allowed to react at a constant temperature for a certain period of time.

The resin thus obtained is washed with an organic solvent, thoroughly washed with water, and then exchanged with the desired counterion. The ion exchange resin thus obtained is filled into a suitable ROMAT tube and used as a separation column or the like to perform ion exchange chromatography or the like.

The above-mentioned trimming method will be explained in more detail with reference to a specific example as follows. First, hydroxyalkyl methacrylate crosslinked polymer gel (particle size 12μi) 2.5
g (dry weight) was dispersed in 1,4-dioxane of 1011 and stirred with a stirrer. To this gel slurry, a particle size of 0.05 μm was added, and trimethylamine was introduced into tetraloethyl methacrylate and hydroxy methacrylate.
A methanol suspension (latex concentration I%) of grade ammonium type anion exchange latex (ion exchange capacity: 0.45 meq/g) 1. 5 g was added and reacted for 5 hours in a shaker at 45°C using boron trifluoride diethyl ether complex as a catalyst.After washing the resin after the reaction with dioxane 501,
It was washed with methanol 1001 and then with 100 ml of pure water, then dispersed in 0.5N sulfuric acid, subjected to ultrasonic waves for 15 minutes, and then filtered. Furthermore, 0.5N sulfuric acid 5
After washing with 011, the filtrate was washed with pure water until it became neutral, dispersed in 1001 pure water, and separated with 1001 using a centrifuge.
Decantation was performed six times at a rotational speed of ,0OOrpIl. Thereafter, it was dispersed in 0.1N sodium chloride and left overnight. The anion-exchanged ttA resin thus obtained had an ion-exchange capacity of 25μ[:q,'g.

Incidentally, the structure of the ion exchange resin (filler) produced as described above is as shown in FIG. In FIG. 2, 1 is a base material made of, for example, an anion exchange resin;
3 is an anion exchange latex made of, for example, an anion exchange group or an anion exchange resin itself, and 3 is a latex-fixed polymer layer formed by bonding the base material 1 and the anion exchange latex 2, for example, with an ether bond. As shown in FIG. 2, the ion exchange resin produced by the production method of the present invention is composed of three parts: a base material 1, an ion exchange latex 2, and a latex fixed polymer layer 3. is resin (base material) 1 holding anion exchange latex 2
It is designed to cover the

Further, the base material 1 must be a crosslinkable polymer gel and must have the following functional groups on its surface or be capable of introducing the functional groups 1. That is, it is necessary that the resin has a halogen group, a hydroxyl group, or an epoxy group,
For example, it is necessary that the resin has polyhydroxyalkyl methacrylate, polyvinyl alcohol, polyglycidyl methacrylate, polyglycidyl ether, polymethylolstyrene, or polychloromethylstyrene or can be introduced with such a functional group.

Furthermore, the ion exchange latex 2 has a particle size of 0.01 to 0.
．． It is a 1 μm strong anion exchange resin, and its base material may be polystyrene-based or polymethacrylate-based.

However, the base material 1 must have a hydrophilic group (hydroxyl group or epoxy group). When an ion exchange resin with good alkali resistance is required, a polystyrene type is preferable, and when more hydrophilicity is required, a methacrylate type is preferable.Also, the shape of the anion exchange latex 2 is not necessarily spherical. A crushed type may also be used. The latex-fixed polymer layer 3 is a substance that reacts with the hydroxyl group, halogen group, or epoxy group of the base material 1 and also reacts with the surface functional groups of the anion exchange latex 2, and is cross-linked on the surface of the base material 1. It is made of a monomer that can coat the surface of the base material 1. When the actual substance is a hydroxyl group or an epoxy group, a polyfunctional epoxy compound such as glycerin polyglycidyl ether is preferable. In addition, an oligomer of an epoxy compound may be used as long as the substance has a relatively large amount of residual epoxy groups.Also, if the remaining functional group in the base material 1 is a halogen group, it can react with the halogen group and A compound that also reacts with a polyfunctional epoxy compound (for example, a polyol compound) and a polyfunctional epoxy compound may be mixed and reacted to form a polymer layer.

On the other hand, the latex fixed polymer layer 3 is made by polymerizing the monomers added during the above-mentioned manufacturing process, and since this monomer also reacts with the surface functional groups (hydroxyl groups, halogen groups, epoxy groups) in the base material, The latex fixed polymer layer 3 formed by the reaction is also chemically bonded and fixed to the base material 1. Furthermore, since this monomer is a polyfunctional monomer, the latex fixed polymer layer formed by polymerization is a crosslinkable polymer layer. Therefore, this polymer layer 3 does not peel off from the base material 1, and the anion exchange latex 2 is fixed to the base material (resin) 1 by coating with the latex fixing polymer N3. The monomer for forming the molecular layer 3 reacts with the surface functional groups of the anion exchange latex, and also penetrates into the micropores and polymerizes.
#J is fixed more firmly than a simple covering. Ion exchange of the present invention! lII! Since the 51J resin has the above-mentioned structure and retains the anion exchange latex 2, the anion exchange latex will not be desorbed by organic solvents or high ion concentration solutions, and the base material 1. Anion exchange latex 2
．． Since the latex fixed polymer layer 3 and the latex fixed polymer layer 3 are chemically bonded together, the anion exchange latex 2 is hardly detached even under mechanical load. Since the base material 1 is covered with a strong shell made of a crosslinkable polymer, the degree of swelling and contraction of the base material 1 is reduced, which has the secondary effect of improving pressure resistance.

In addition, the base material 1 and the anion exchange latex (ion exchange group or resin itself) 2 have hydrophilic groups, and the latex fixed polymer layer 3 is also hydrophilic, making it a hydrophilic resin suitable for separating hydrophobic samples. becomes.

The anion exchange resin produced as described above was packed into a stainless steel column with an inner diameter of 4.6 ml and a length of 1100 nm, and subrest type ion chromatography was performed using an alkaline mobile phase. The analysis conditions at this time were that the mobile phase was 1.76nHNa2CO310, 48IIHNaHCO
3 (pH 10,3), 2.011/nin, the measurement temperature is 45 ° C, the detector is a conductivity detector,
Sample concentration is CI-10ppn, NO-320ppJPO
42-20ppn, 804'-20ppl, and the sample injection amount was 50μ! It is. In the chromatogram obtained under such analysis conditions, the analyte contained in the injected sample was separated in a short time with a good peak shape, indicating that the anion exchange resin obtained by the production method of the present invention Ion chromatography cannot be performed adequately. Furthermore, when the base material itself (resin before reaction) used in the previous example was packed into a column with the same column size as this example (inner diameter 4.6i11, length 100nn), the filling flow rate was 3. Although it was 8 nl/in, the resin after reaction could be filled at 4.5 nl/nin. This means that the flow resistance (pressure resistance) of the base material is improved by using the manufacturing method of the present invention. Although this is different from the purpose of the present invention, it can be said that this is a side effect obtained by the present invention.

Furthermore, in order to investigate the stability of the resin of the present invention against desorption of the anion exchange latex, tests were conducted by extracting the packing material from the column of the above example and dispersing it in various solutions. That is, first, in order to examine the stability against organic solvents, the outstanding resin was dispersed in isopropyl alcohol and shaken in a constant temperature bath at 50° C. for 8 hours. Thereafter, the resin was washed with pure water, packed into the same stainless steel column as in the previous example, and subjected to ion chromatography. As a result, there was no change in the retention time of each ion. This indicates that no desorption of the anion exchange latex occurred in the organic solvent.Next, the same resin was dispersed in 1H sodium chloride and 1N hydrochloric acid and a similar test was conducted. In the case of , no shortening of the retention time was observed, indicating that the anion exchange latex was stably retained on the base resin. From these experimental results, it can be seen that the resin of the present invention is more stable in simple pasting than in molds. Furthermore, we have actually investigated the stability of conventional latex-type fillers, but with fillers retained with a binder, the retention time is up to about 173 when dispersed in 50% in-10V alcohol. Decrease. In addition, shortening of the retention time is observed even by stirring with a starter or shaking for a long time. There is not much knowledge about electrostatic adsorption molds, but when treated with a solution of high ionic strength, a shortening of the holding time is observed, although no decrease in gluing is observed when the mold is treated with an organic solvent. It is also said that its stability in organic solvents is not very good.

<Effects of the Invention> According to the embodiments of the present invention as described in detail above, the surface of the base material 1 holding the anion exchange latex 2 is reacted with the surface functional groups of the base material 1 and the anion exchange latex 2. By fixing the anion exchange latex 2 by coating it with a crosslinkable polymer (latex fixed polymer layer 3),
It has become possible to produce a highly stable anion exchange resin without desorption of the anion exchange latex. In addition, the latex fixed polymer layer 3 is a three-dimensional crosslinkable polymer that covers the base material 1 with a strong shell, which reduces the degree of swelling and contraction of the base material 1 and improves pressure resistance. There were also secondary effects. Furthermore, since the resins of the base material 1 and the anion exchange latex 2 themselves have hydrophilic groups, and the latex-fixed polymer layer 3 is also hydrophilic, the resins are hydrophilic resins suitable for separating hydrophobic samples.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the manufacturing method according to the embodiment of the present invention, and the second
The figure is a schematic diagram of an anion exchange resin produced according to the method of the embodiment of the present invention.

Claims (2)

[Claims] (1) A base material made of a resin that is a crosslinkable polymer gel and has a halogen group, a hydroxyl group, or an epoxy group on its surface; a cation exchange latex physically adsorbed on the base material; and the base material. A method for producing a cation exchange resin, which comprises a latex immobilized polymer layer chemically bonded to the surface of the cation exchange resin and is used in high performance liquid chromatography, by the following steps (a) to (e). (a) A step of preparing a polymer gel having hydroxyl groups, halogen groups, or epoxy groups depending on the reaction method. (b) A step of dispersing the polymer gel in a small amount of an organic solvent, and then dispersing the ion exchange latex in the organic solvent. (c) A step of gradually adding and stirring the ion exchange latex suspension to the polymer gel slurry, and then mixing a polyfunctional epoxy compound to form the fixed polymer layer with the slurry. (d) A step in which a reaction initiation catalyst is added and the reaction is carried out at a constant temperature for a certain period of time. (e) Wash with an organic solvent and then thoroughly with water, and then
The process of exchanging to the desired positive ion. (2) The cation exchange resin according to claim 1, wherein the base material is polyhydroxyalkyl methacrylate, polyvinyl alcohol, polyglycidyl methacrylate, polyglycidyl ether, polymethylolstyrene, or polychloromethylstyrene. Production method.