JP2000221179A - Crosslinking polymer particles for anion analysis liquid chromatography, their forming method and usage - Google Patents

Abstract

PROBLEM TO BE SOLVED: To measure anions with high sensitivity by water suspension polymerizing one or, two or more monomers of groups of acrylates with a hydroxyl group and methacrylate-based crosslinking monomers and introducing a quaternary ammonium group. SOLUTION: Water suspension polymerization is for conducting suspension polymerization in a water medium. Water is essential as the water medium. A weight ratio to monomers is 300-1,000 wt.%, preferably 400-800 wt.%. An appropriate diluent is added to a monomer phase at the time of polymerization, whereby porous crosslinking polymer particles are obtained. An acrylate with a hydroxyl group or methacrylate-based bridging monomer is singly water suspension polymerized, thereby obtaining a crosslinking gel, and further a quaternary ammonium group is introduced via a spacer, whereby crosslinking polymer particles for anion analysis liquid chromatograph with a high mechanical strength can be obtained. Since the particle is of small size and has high mechanical strength, the particle exerts a superior separation performance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to crosslinked polymer particles for anion analysis liquid chromatography, a method for producing the polymer particles, and a column for anion analysis liquid chromatography which is filled with the polymer.

[0002]

2. Description of the Related Art Conventionally, anion analysis liquid chromatography has been known as one type of liquid chromatography. In recent years, anion analysis liquid chromatography has been used to analyze inorganic ions such as phosphate ion, fluoride ion, chloride ion, nitrite ion, bromide ion, nitrate ion and sulfate ion efficiently, with high precision and high sensitivity. It is used as an important means. Anion analysis liquid chromatography includes a suppressor method (method using a suppressor) and a non-suppressor method (method using no suppressor). In the former, a cation removal system consisting of an ion exchange membrane or an ion exchange resin called a suppressor is connected to the separation column. As the eluent, carbonate buffer, borate buffer and sodium hydroxide aqueous solution of pH 10 to 12 are used. After the anions are separated by the separation column, the cations are removed by the suppressor. Degree detector. On the other hand, the non-suppressor method uses a low-conductivity organic acid such as phthalic acid, p-hydroxybenzoic acid, and trimesic acid as an eluent, and anions are detected by a direct conductivity detector after being separated by a separation column. You. The background of the conductivity detector is low, and highly sensitive analysis is possible. The pH of the eluent is not particularly limited, and various separation conditions can be selected. As a filler commonly used for a non-suppressor column, there is a chemically bonded ion exchanger formed by copolymer particles of a vinyl ester or vinyl ether-containing monomer having a hydroxyl group and a vinyl ester or vinyl ether crosslinkable monomer. The above-mentioned packing material is packed in a non-suppressor column generally used in the past, but in order to improve the performance of the column, it was necessary to make the packing material smaller than before.

[0003]

However, the filler has insufficient mechanical strength and it is not easy to reduce the particle size. The present invention has been made in view of such circumstances, the crosslinked polymer particles for anion analysis liquid chromatography useful as a high mechanical strength micro-filler, a method for producing the same and filling the crosslinked polymer particles. And a column for anion analysis liquid chromatography.

[0004]

Means for Solving the Problems The present inventors have conducted aqueous suspension polymerization of only one or two or more monomers selected from the group consisting of acrylates having a hydroxyl group and methacrylate-based crosslinkable monomers to obtain a crosslinked gel. Further, they have found that fine crosslinked polymer particles having high mechanical strength can be obtained by further introducing a quaternary ammonium group through a spacer, and have completed the present invention. That is, the present invention relates to the following matters. (1) One or two or more monomers selected from the group consisting of acrylates and methacrylate-based crosslinkable monomers having a hydroxyl group are subjected to aqueous suspension polymerization, and quaternary via a spacer using the hydroxyl groups of the obtained crosslinked gel. Crosslinked polymer particles having an ammonium group introduced therein for anion analysis liquid chromatography. (2) The crosslinked polymer particles for anion analysis liquid chromatography according to the above (1), wherein the particle diameter is 1 to 50 µm. (3) A filler for anion analysis liquid chromatography using the crosslinked polymer particles for anion analysis liquid chromatography according to (1) or (2). (4) One or two or more monomers selected from the group consisting of acrylates and methacrylate-based crosslinkable monomers having a hydroxyl group are subjected to aqueous suspension polymerization, and quaternary via a spacer using the hydroxyl groups of the obtained crosslinked gel. (1) or (2) above, wherein an ammonium group is introduced.
3. The method for producing crosslinked polymer particles for anion analysis liquid chromatography according to item 1. (5) A column for anion analysis liquid chromatography, which is filled with the crosslinked polymer particles for anion analysis liquid chromatography according to (1) or (2).

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention provides a crosslinked polymer for anion chromatography obtained by homopolymerizing a crosslinkable monomer having a hydroxyl group to obtain a high-strength crosslinked gel and further introducing a quaternary ammonium group through a spacer. The present invention relates to particles, a method for producing the crosslinked polymer particles, a filler for anion chromatography comprising the crosslinked polymer particles, and a column for anion chromatography filled with the crosslinked polymer particles.

[0006] The hydroxyl group of one or more monomers selected from the group consisting of acrylate and methacrylate type crosslinkable monomers having a hydroxyl group used in the present invention is:
Indispensable for introducing a quaternary ammonium group through a spacer. As the acrylate or methacrylate-based crosslinkable monomer having a hydroxyl group used in the present invention,
Glycerin diacrylate, glycerin dimethacrylate, pentaerythritol diacrylate, pentaerythritol dimethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, sorbitol diacrylate, sorbitol dimethacrylate, etc., among which glycerin dimethacrylate is particularly preferred. Is preferably used alone.

In the present invention, one or more monomers selected from the group consisting of an acrylate having a hydroxyl group and a methacrylate-based crosslinkable monomer are subjected to aqueous suspension polymerization to form a crosslinked gel. In the aqueous suspension polymerization, suspension polymerization is performed in an aqueous medium. Water is essential as the aqueous medium, and its weight ratio to the monomer is 300 to
1000% by weight, more preferably 400 to 800%
% By weight.

In the present invention, the polymerization is carried out in the presence of a polymerization initiator. As the polymerization initiator used, benzoyl peroxide, dichlorobenzoyl peroxide, dicumyl peroxide, 2,
5-di (peroxybenzoate) hexyne-3,1,
3-bis (tert-butylperoxyisopropyl) benzene, lauroyl peroxide, tert-butyl peracetate, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexyne-3,2,5-dimethyl-2 Organic peroxides such as 2,5-di (tert-butylperoxy) hexane and tert-butyl perbenzoate, methyl ethyl ketone peroxide, 2,2′-
Examples include azo-based compounds such as azobis (isobutyronitrile) and 2,2′-azobis (2,4-dimethylvaleronitrile). Among these, 2,2'-azobis (isobutyronitrile) is preferably used. The amount of the polymerization initiator used is appropriately determined depending on the type of the monomer and the like, but is used in an amount of 0.1 to 4.0% by weight based on the amount of the monomer.

In the present invention, an appropriate water-soluble polymer is used as a dispersant and an inorganic salt is used as a dispersant in order not to hinder the stability of the suspension system. Examples of the water-soluble polymer include gelatin, starch, CMC, polyvinyl alcohol, partially saponified polyvinyl alcohol, a vinyl alcohol copolymer, and polyacrylic acid. Of these, polyvinyl alcohol is preferably used. Further, as a dispersing aid, sodium chloride,
Potassium chloride, sodium sulfate and the like can be mentioned, and preferably, sodium chloride is used.

Further, by adding an appropriate diluent to the monomer phase at the time of polymerization, porous crosslinked polymer particles can be obtained. By making the crosslinked polymer particles porous, the amount of functional groups that can be introduced can be increased, and the performance as a simple substance for anion analysis chromatography can be improved. As the diluent used in the present invention, toluene, diethylbenzene, n-hexane, n-dodecane,
Examples thereof include n-hexanol, cyclohexanol, octanol, dodecanol, propyl acetate, and butyl acetate. Of these, n-hexanol is preferably used. These diluents may be used alone or as a mixture of two or more. The diluent is used in an amount of 0 to 200% by weight based on the amount of the monomer. However, if the amount of the diluent is small, it is difficult to make the obtained polymer porous, and if the amount of the diluent is too large, the porosity of the obtained polymer is large. Tends to be too large and the mechanical strength tends to be low.

The polymerization reaction in the present invention is usually carried out at 60 to
At a temperature of 90 ° C., it is preferably performed for about 6 to 10 hours. The crosslinked gel obtained by polymerization has a particle size of 1 to 50 μm.
m, preferably 2 to 20 μm, more preferably 3 to 10 μm.
Spherical particles of μm are preferred, and these are classified and used as necessary.

[0012] The crosslinked gel obtained by the above-mentioned method is intended to facilitate the introduction of quaternary ammonium groups and to obtain good separation when performing anion analysis. An epoxy group is introduced via a spacer such as butanediol diglycidyl ether or ester, polyethylene glycol diglycidyl ether or ester, and then a quaternary ammonium group is obtained to obtain crosslinked polymer particles for anion analysis liquid chromatography. . Among the above spacers, 1,4-butanediol diglycidyl ether is preferably used. Next, a crosslinked polymer particle for anion analysis liquid chromatography is obtained by introducing a quaternary ammonium group using trimethylamine, tributylamine, 1-methylpiperidine, N-methyldiethanolamine or the like.

The obtained crosslinked polymer particles for anion analysis liquid chromatography are packed into a column in accordance with a known packing method such as a slurry method, and a column for high sensitivity anion analysis liquid chromatography is obtained. You.

[0014]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

The measurement by anion analysis liquid chromatography and the evaluation of mechanical strength are carried out by the following methods. 1) Anion analysis liquid chromatography Eluent: 8 mM p-hydroxybenzoic acid (pH 4.1)
pH adjustment: Bis-Tris) +2 mM phenyl borate + 0.005 mM + trans-1,2-cyclohexanediaminetetraacetic acid Eluent flow rate: 1.0 ml / min, column temperature: 40 ° C. Detector: electric conductivity detector 2) Mechanical Strength The crosslinked polymer particles for anion analysis liquid chromatography were packed in a column, and the measurement was repeated for 500 hours under a certain condition, and the mechanical strength was evaluated by the degree of decrease in the number of theoretical plates.

(Example) In a 300 ml beaker, 100 g of glycerin dimethacrylate, 50 g of n-hexyl alcohol, 2,2'-azobis (isobutyronitrile)
1.5 g of the mixture was mixed with 2% PVA-224, 2% NaCl
The mixture was suspended in 333 ml and mixed at room temperature for 40 minutes under high-speed stirring using a homogenizer. Thereafter, the mixture was transferred to a reaction vessel equipped with a stirring rod, and the temperature was set at 63 ° C. (external temperature). Warming gave a crosslinked gel insoluble in water and organic solvents. This gel was centrifuged to collect the precipitate, washed with 500 ml of water and 500 ml of ethanol, air-dried, and classified by air classification to obtain particles of 3 to 6 μm.
To 20 g of the crosslinked gel particles, the following general formula (I)

Embedded image In order to introduce a spacer by the reaction mechanism shown in (1), 40 g of 1N-NaOH and 40 g of 1,4-butanediol diglycidyl ether were weighed into an eggplant-shaped flask, and the mixture was heated at 30 ° C.
And reacted for 3 hours to obtain 1,4-butanediol diglycidyl etherified crosslinked polymer particles. The particles were washed with 100 ml of water and 100 ml of acetone and air-dried.

The following general formula (II)

Embedded image In order to quaternize the 1,4-butanediol diglycidyl etherified crosslinked polymer particles with the reaction mechanism shown in the following, 10 g of 1,4-butanediol diglycidyl etherified crosslinked polymer particles, 10 g, 45 g of 4-dioxane and 7.5 g of N-methylpiperidine were weighed out, stirred at 35 ° C. for 1 hour, and reacted to obtain quaternary ammonium-modified crosslinked polymer particles. The particles are treated with acetone 100
2 times with water, 100 ml of water, 100 m of 0.5N-HCl
l, 100 ml of water, 100 ml of 0.1 N NaOH
Washed three times with 100 ml of water three times.

The crosslinked polymer particles obtained by the above means are packed as a chemically bonded ion exchanger using crosslinked polymer particles for anion analysis liquid chromatography in a stainless steel column of 4.6 mm in diameter × 100 mm in length. A column for ion analysis liquid chromatography was prepared. As a sample, phosphate ion 20 mg / l, fluoride ion 1.5
mg / l, chloride ion 2.5 mg / l, nitrite ion 6 mg / l, bromide ion 10 mg / l, nitrate ion 1
Aqueous solution containing 0 mg / l, sulfate ion 10 mg / l 50
The column was evaluated by injecting μl, and a chromatogram as shown in FIG. 1 was obtained.

The theoretical plate number of each ion in FIG. 1 is 4200 steps of phosphate ion / 10 cm, 3800 steps of fluoride ion.
Step / 10cm, chloride ion 7100 step / 10cm, nitrite ion 7600 step / 10cm, bromide ion 700
0 stage / 10 cm, nitrate ion 7000 stage / 10 cm, and sulfate ion 7600 stage / 10 cm.

Comparative Example Shodex was used as a separation column.
(Registered trademark: Showa Denko KK) The measurement was performed using IC I-524A under the same conditions as in Example 1. The obtained chromatogram is shown in FIG. The theoretical number of nitrate ions in FIG. 2 was 3000 steps / 10 cm.

[0021]

According to the present invention, the acrylate or methacrylate crosslinkable monomer having a hydroxyl group is subjected to aqueous suspension polymerization alone to obtain a crosslinked gel, and further, a quaternary ammonium group is introduced via a spacer to obtain a mechanically-functionalized product. The crosslinked polymer particles for anion analysis liquid chromatography having high mechanical strength can be obtained. Since the crosslinked polymer particles for anion analysis liquid chromatography obtained by the present invention have a small particle size and high mechanical strength, a column for anion analysis liquid chromatography using the same has excellent separation performance. . Therefore, it is useful for highly sensitive anion measurement in anion chromatography.

[Brief description of the drawings]

FIG. 1 is a separation chromatogram obtained in an example.

FIG. 2 is a separation chromatogram of a comparative example.

[Explanation of symbols]

1. 1. Phosphate ion (H ₂ PO ₄ ⁻ ) 2. Fluoride ion (F ⁻ ) 3. chloride ion (Cl ⁻ ); 4. Nitrite ion (NO ₂ ⁻ ) Bromide ion (Br ^-) 6. 6. Nitrate ion (NO ₃ ⁻ ) Sulfate ion (SO ₄ ^2- )

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kazunori Iwata 1-13-9 Shiba-Daimon, Minato-ku, Tokyo Inside Showa Denko KK (72) Inventor Hisako Sakuma 5-1 Ogimachi, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture Showa Inside the Kawasaki Plant of Denko Corporation (72) Inventor Takashi Kozuka 5-1 Ogimachi, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture Showa Inside the Kawasaki Plant (72) Inventor Kuniko Igarashi 5-1 Ogimachi, Kawasaki-ku, Kawasaki City, Kanagawa Prefecture F term in Kawasaki Plant of Electric Works Co., Ltd. (reference) 4J100 AL66P BA03P BA33H CA01 CA04 CA23 FA03 FA21 HA61 JA17

Claims (5)

[Claims] 1. Aqueous suspension polymerization of one or more monomers selected from the group consisting of acrylates having a hydroxyl group and methacrylate-based crosslinkable monomers, and via a spacer using the hydroxyl groups of the obtained crosslinked gel. Crosslinked polymer particles having an introduced quaternary ammonium group for anion analysis liquid chromatography. 2. The crosslinked polymer particle for anion analysis liquid chromatography according to claim 1, wherein the particle size is 1 to 50 μm. 3. A filler for anion analysis liquid chromatography using the crosslinked polymer particles for anion analysis liquid chromatography according to claim 1 or 2. 4. An aqueous suspension polymerization of one or two or more monomers selected from the group consisting of acrylates having a hydroxyl group and methacrylate-based crosslinkable monomers, and via a spacer using the hydroxyl groups of the resulting crosslinked gel. The method for producing crosslinked polymer particles for anion analysis liquid chromatography according to claim 1 or 2, wherein a quaternary ammonium group is introduced. 5. A column for anion analysis liquid chromatography, comprising the crosslinked polymer particles for anion analysis liquid chromatography according to claim 1 or 2.