JPH07103206B2 - Method for producing crosslinked polymer particles - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing crosslinked polymer particles. Specifically, it relates to a method for producing crosslinked polymer particles having a narrow particle size distribution in the particle size range of 1 to 30 μm.

[Conventional technology]

Although polymer particles having a particle size of around 10 μm are in high demand in a wide range of industrial fields, their production is generally not easy.

As a conventional method for producing polymer particles, a suspension polymerization method,
Emulsion polymerization method and dispersion polymerization method are known. In the suspension polymerization method, polymer particles are produced by suspending monomer oil droplets in an aqueous medium by a mechanical force and polymerizing, and the particle size of the particles obtained by the method is usually 100 μm or more, around 10 μm. It is extremely difficult to obtain polymer particles having a particle size of. Further, there is a drawback that the particle size distribution of the polymer particles obtained by dispersing the monomer oil droplets by a mechanical force becomes wide and a classification operation is required. Therefore, the yield becomes worse as the polymer particles having a narrow particle size distribution are obtained.

On the other hand, in the emulsion polymerization method using a surfactant for emulsion dispersion,
Although polymer particles having a very narrow particle size distribution can be obtained, the particle size of polymer particles usually obtained is 1 μm or less, and it is substantially impossible to obtain polymer particles having a particle size of around 10 μm.

In addition, in the dispersion polymerization method, in which the polymerizable monomer dissolves but the polymer that forms does not dissolve, the degree of crosslinking is
It is extremely difficult to produce particles with a high degree of crosslinking of 2.0% or more because the particles agglomerate. In addition, there is a drawback that when the particles having a particle diameter of 10 μm or more are obtained, the particle diameters are generally uneven.

In addition to the methods described above, the seed polymerization method is known as a method that has been actively studied in recent years.

This method absorbs the polymerizable monomer of polymer particles obtained by emulsion polymerization (hereinafter referred to as "seed polymer"),
This is a method for obtaining enlarged polymer particles by polymerizing this, but this method points out the following drawbacks. That is, since the particles obtained by emulsion polymerization have a very small particle diameter, the seed polymer must be a non-crosslinked linear particle in order to enlarge the particle size to 1 μm or more. That is, when the seed polymer is crosslinked, the degree of enlargement is limited, and it is extremely difficult to enlarge to around 10 μm. In JP-A-54-97582, a chain transfer agent is added during emulsion polymerization to synthesize a linear polymer having a molecular weight much lower than that of an ordinary polymer latex, and this is used as a seed polymer. A method of polymerizing by absorbing a polymerizable monomer which is somewhat soluble in water is disclosed. However, in this method, the size of the polymer particles to be obtained is limited, and the use of a commonly used oil-soluble polymerization initiator or water-soluble polymerization initiator causes problems such as generation of coagulation or generation of new particles. However, it is difficult to reliably obtain polymer particles in good yield.

Further, in JP-A-54-126288, the first polymerization
In the step, the seed polymer is allowed to absorb an organic compound having a solubility in water of less than 10 ^-2 g / l (10 ^-3 % by weight), which functions as a swelling aid, and then in the second step,
Usually 20-300 times the capacity of the seed polymer, even at maximum
A method is disclosed in which a monomer that is somewhat soluble in 1,000 times water is absorbed to form swollen particles of the monomer, and then polymerization is performed while maintaining the particle shape.

However, this method has a drawback that the absorption capacity of the polymerizable monomer is not so high because the absorption amount of the swelling aid into the seed polymer is small, and therefore the polymer particles are not sufficiently enlarged. Ie 1
The maximum particle size of the polymer particles obtained by the step polymerization is about 10 times the particle size of the seed polymer. Therefore, for example, using a seed polymer with a particle size of 0.5 μm, the particle size of 10 μm
In order to produce the polymer particles of, it is necessary to first polymerize the polymer particles having a particle size of about 3 μm using 0.5 μm of the seed polymer, and then repeat the same polymerization process using the polymer particles as the seed polymer. Therefore, there is a drawback that the number of steps is large and the manufacturing is not easy.

On the other hand, for the purpose of avoiding the above-mentioned drawbacks, Japanese Patent Laid-Open No.
61-190504 discloses a method of enlarging linear polymer particles by 1000 times or more in volume. In this method, in order to efficiently enlarge the swelling, a swelling aid composed of an organic compound having a water solubility of 0.02% by weight or less and a molecular weight of 5,000 or less is first absorbed by the seed polymer and then the polymerizable monomer is absorbed. Polymerize. However, this method has a manufacturing difficulty in that it takes 66 hours just to absorb the swelling aid.

In any of the above-mentioned seed polymerization methods, since the seed polymer is extremely enlarged in any method, there is a drawback that the properties of the polymer used for the seed are not reflected in the properties of the enlarged polymer particles finally obtained. . Further, in this method, it is necessary to extract and remove the linear polymer used for the seed, and the polymer particles finally obtained are not a little porous, which makes it difficult to produce gel-type polymer particles.

The problems of the above-mentioned conventional technology are summarized as follows.

(B) Polymer particles having a wide particle size distribution and a uniform particle size cannot be obtained by the suspension polymerization method.

(B) Polymer particles having a particle size of 1 μm or more cannot be obtained by the emulsion polymerization method.

(C) Polymer particles having a high degree of crosslinking cannot be obtained by the dispersion polymerization method.

(D) In the seed polymerization method, it is necessary to extremely enlarge the seed polymer obtained by emulsion polymerization, and therefore it is necessary to use a specific type of swelling aid. In addition, there is a manufacturing constraint such that the enlargement process requires a long time.

[Problems to be Solved by the Invention]

The object of the present invention is to solve the above-mentioned drawbacks of the prior art and to provide polymer particles having a crosslinking degree of 0.5 to 98% and a particle diameter of 1 to 30 μm, an arbitrary crosslinking degree and a particle diameter, and a narrow particle diameter distribution. It is to provide a method of manufacturing.

[Means for Solving the Problems]

That is, according to the present invention, in the first step, the crosslinked polymer particles are produced by polymerizing the polymerizable monomer containing the crosslinkable monomer in a medium in which the polymerizable monomer is dissolved but the produced polymer is not dissolved. In the above, the gist is a method for producing crosslinked polymer particles, which comprises polymerizing the obtained crosslinked polymer particles after absorbing a polymerizable monomer containing a crosslinkable monomer.

Examples of the polymerizable monomer that can be used in the first step of the present invention, that is, the polymerization of the seed polymer, include general vinyl-based monomers. Specifically, styrene, halogenated styrene, aromatic vinyl monomers such as vinylbenzyl glycidyl ether, ethylenically unsaturated carboxylic acids such as acrylic acid and methacrylic acid, methyl acrylate, methyl methacrylate, glycidyl acrylate, and methacrylic acid. Ethylenically unsaturated carboxylic acid ester such as glycidyl acid salt, 2-hydroxyethyl acrylate, and methacrylic acid-2 (N, N′-dimethylamino) ethyl,
And acrylamide and the like.

Further, as the crosslinkable monomer that can be used in the polymerization of the seed polymer, an aromatic divinyl compound such as divinylbenzene, a diethylenically unsaturated carboxylic acid ester such as ethylene glycol dimethacrylate, 1,7
Examples thereof include aliphatic diolefin compounds such as octadiene, conjugated diolefins such as butadiene and isoprene, and methylenebisacrylamide.

The degree of crosslinking of the seed polymer in the present invention is 0.1 to 2.0%,
It is preferably 0.3 to 1.5%. Here, the degree of crosslinking means the weight ratio of the crosslinkable monomer in all the monomers. However, when a polymerizable monomer such as glycidyl acrylate or glycidyl methacrylate is used, a part of the monomer acts as a crosslinkable monomer, and therefore a seed polymer which is preferable even in the range of the above crosslinking degree or less. Can be obtained.

In the first step of the present invention, in order to obtain polymer particles having a desired particle diameter, when the heat of vaporization of the medium used is ΔE and the molar volume is V, the solubility parameter represented by (ΔE / V) ^1/2 Should be selected appropriately. That is, the larger the difference between the solubility parameter of the polymer particles produced and the solubility parameter of the medium used, the smaller the particle size of the polymer particles produced. The medium used in the present invention has a solubility parameter of 10.0.
(Cal / cm ³ ) ^1/2 or more and 20.0 (cal / cm ³ ) ^1/2 or less, preferably 10.6 (cal / cm ³ ) ^1/2 or more and 16.5 (cal / cm ³ ) ^1/2 or less Things are used. Specifically, alcohols such as methanol, ethanol, 2-propanol and 2-methyl-2-propanol, ethers / alcohols such as these alcohols and 2-methoxy-ethanol, ethers such as tetrahydrofuran and dioxane,
Further, a mixture of these various solvents and water may be mentioned.

Further, in the present invention, a diluent may be used, if necessary, in the polymerization of the seed polymer in order to moderate a rapid change in the solubility parameter in the reaction system. The amount used can be changed according to the type of polymerizable monomer and the amount used, and its solubility parameter is 8.0 [cal / c
It is preferably in the range of m ³ ] ^1/2 or more and 9.0 [cal / cm ³ ] ^1/2 or less. Specific examples thereof include cyclohexane and xylene.

In the present invention, it is preferable to use a dispersion stabilizer during polymerization of the seed polymer in order to prevent aggregation, deformation and fusion of generated polymer particles and increase the dispersion stability thereof. As the dispersion stabilizer, various types of homopolymers, copolymers, graft polymers, synthetic polymer compounds such as block polymers, and natural polymer compounds and their derivatives can be used. Specifically, polyvinylpyrrolidone, polyvinyl methyl ether, polyethyleneimine, polyacrylic acid,
Examples thereof include vinyl alcohol-vinyl acetate copolymer, ethyl cellulose, hydroxypropyl cellulose and the like.

Further, in the polymerization of the seed polymer, a co-stabilizer may be used in addition to the above-mentioned dispersion stabilizer in order to promote the polymerization more stably and enhance the dispersion stability. Anionic surfactants, nonionic surfactants, quaternary ammonium salts, long-chain alcohols and the like are used as such auxiliary stabilizers. Specific examples thereof include sodium di (2-ethylhexyl) sulfosuccinate, nonylphenoxypolyethoxyethanol methyl tricaprylyl ammonium chloride, cetyl alcohol and the like.

Further, as the polymerization initiator that can be preferably used in the polymerization of the seed polymer of the present invention, 2,2′-azobisisobutyronitrile, 4,4′-azobis- (4-cyanopentanoic acid), 2, Azo polymerization initiators such as 2'-azobis- (2-methylbutyronitrile) and 2,2'-azobis- (2,4-dimethylvaleronitrile), peroxides such as benzoyl peroxide, etc. You can

The polymerization temperature in the polymerization of the seed polymer in the present invention may be 40 ° C to 90 ° C, preferably 60 ° C to 80 ° C.

A seed polymerization method is used in the second step of the present invention, that is, the enlargement of the seed polymer.

Examples of the seed polymer that can be used in the seed polymerization of the present invention include cross-linked polymers such as the styrene-based cross-linked polymer and the acrylic cross-linked polymer obtained in the first step.

These seed polymers can be used in the form of dispersions such as emulsions and suspensions.

The particle size of the seed polymer depends on the particle size of the target polymer.
It can be arbitrarily selected within a range of 1/4 or more, and the polymer particles obtained in the present invention can be used as a seed polymer in the next step to produce larger polymer particles.

In the present invention, in order to prevent generation of new particles in the dispersion medium phase during polymerization, it is preferable to impregnate the seed polymer with the polymerization initiator before impregnating the polymerizable monomer. At this time, in order to impregnate the seed polymer with the polymerization initiator, for example, a solution obtained by dissolving the polymerization initiator in a small amount of a solvent is dispersed in water, and then the seed polymer is dispersed in an aqueous dispersion. The solvent in which the polymerization initiator is dissolved becomes a dispersed oil droplet and comes into contact with the seed polymer in water, and the solvent in which the polymerization initiator that is a dispersed oil droplet is dissolved is impregnated into the seed polymer. The method can be adopted. The time for impregnating the polymerization initiator can be usually several hours. As the solvent of the polymerization initiator,
It must be either insoluble in the dispersing medium of the seed polymer or have a very low partition coefficient. Specific examples thereof include aromatic compounds such as benzene, toluene and xylene, and halogenated aliphatic compounds such as 1,2-dichloroethane and 1,1 ', 2-trichloroethane.

Polymerization initiators that can be preferably used in the seed polymerization of the present invention include 2,2′-azobisisobitylonitrile, 4,4′-azobis (4-cyanopentanoic acid), 2,
2'-azobis (2-methylbutyronitrile), 2,2'-
Azo-based polymerization initiators such as azobis (2,4-dimethylvaleronitrile), benzoyl peroxide, lauroyl peroxide, octanoyl peroxide, peroxides such as 3,3 ', 5-trimethylhexanoylperoxide Can be mentioned.

Examples of the polymerizable monomer that can be preferably used in the seed polymerization of the present invention include aromatic vinyl monomers such as styrene, halogenated styrene and vinylbenzyl glycidyl ether, and ethylenically unsaturated carboxylic acids such as acrylic acid and methacrylic acid. Acid, ethylenically unsaturated carboxylic acid esters such as methyl acrylate, methyl methacrylate, glycidyl acrylate, glycidyl methacrylate, 2-hydroxyethyl acrylate, and methacrylic acid-2 (N, N'-dimethylamino) ethyl These polymerizable monomers can be used alone or in combination according to the purpose.

Examples of the crosslinkable monomer that can be used in the seed polymerization of the present invention include aromatic divinyl compounds such as divinylbenzene, diethylenically unsaturated carboxylic acid esters such as ethylene glycol dimethacrylate, and aliphatic divinyl compounds such as 1,7-octadiene. Examples thereof include olefin compounds and conjugated diolefins such as butadiene and isoprene.

The degree of charge crosslinking in the seed polymerization of the present invention is 1 to 100%.
Is.

Furthermore, porous polymer particles can be obtained by adding an appropriate diluent to the monomer phase during seed polymerization. As the diluent, an organic solvent having a small swelling property with respect to the produced polymer particles is suitable. Further, in the preparation of the dispersion liquid, it is preferable to use a dispersion stabilizer in order to enhance the dispersibility. As such a dispersion stabilizer, known ones can be used, and examples thereof include anionic surfactants such as sodium dodecylbenzenesulfonate, sodium lauryl sulfate and sodium dialkylsulfosuccinate, and further polyoxyethylene nonylphenyl. Nonionic surfactants such as ether, polyethylene glycol monostearate, sorbitan monostearate,
Synthetic polymer compounds such as polyvinylpyrrolidone, polyethyleneimine, and vinyl alcohol-vinyl acetate copolymer can be used in combination.

In the present invention, at the time of seed polymerization, a dispersion stabilizer is added in order to prevent the aggregation, deformation, and fusion of the seed polymer swelled by absorbing the polymerization initiator and the polymerizable monomer and increasing the dispersion stability. It is necessary to use. As such a dispersion stabilizer, known anionic and nonionic surfactants can be used, and they can also be used in combination with a synthetic polymer compound such as polyvinylpyrrolidone, polyethyleneimine and vinyl alcohol-vinyl acetate copolymer. It is possible.

The polymerization temperature in the seed polymerization of the present invention is usually 40 ° C.
To 90 ° C, preferably 50 ° C to 80 ° C.

〔Example〕

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

Example 1 Polyvinylpyrrolidone K-30 1.8 g, sulfosuccinic acid di-
2-ethylhexyl sodium 0.5g, styrene monomer
Dissolve 12.5 g, divinylbenzene 0.08 g and 2,2'-azobisisobutyronitrile 0.13 g in a mixed medium of ethanol 72.5 g and cyclohexane 13 g, and in a nitrogen gas stream 70
Polymerization was carried out at 8 ° C for 8 hours. The polymerization conversion rate in this polymerization was 95%. Furthermore, when the polymer particles obtained by this polymerization were observed with a scanning electron microscope, the particle size was 2.0
It was confirmed that the particles were truly spherical particles having a very high monodispersity of μm and a standard deviation of 1.0%. Using this as a seed polymer, the following operation was performed.

First, 2,2'-azobis (2,4-dimethylvaleronitrile)
0.015 g, toluene 0.035 g, sodium alkyldiphenyl ether disulfonate "Perex SS-H" 2 x 10 ^-4 g
And 1 g of water were mixed and emulsified, and finely dispersed so that the particle diameter of oil droplets was 0.5 μm or less. This dispersion was obtained by previous polymerization
0.6% cross-linked particle size 2.0 μm 1 part of monodisperse polystyrene, 0.01 g of sodium alkyldiphenyl ether sulfonate “Perex SS-H” and 9 g of water were added to an emulsified aqueous dispersion, and the mixture was slowly stirred at room temperature for 2 hours, The dispersed oil droplets containing the polymerization initiator were absorbed by the seed polymer.

The aqueous dispersion of this seed polymer was then treated with sodium alkyldiphenyl ether sulfonate "Perex SS-
In addition to 48 g of 0.1% aqueous solution of "H", 3.5 g of styrene and 1.3 g of divinylbenzene were added, and the mixture was slowly stirred at 30 ° C for 1 hour to allow the monomer to be absorbed by the seed polymer. Then, polymerization was carried out at 60 ° C. for 7 hours and 70 ° C. for 1 hour.

When the polymer particles obtained by the above polymerization were observed with a scanning electron microscope, it was confirmed that they were true spherical particles having a particle diameter of 3.0 μm and a standard deviation of 1.2% and having extremely high monodispersity. The degree of crosslinking of the obtained polymer particles was estimated to be 9.0% by pyrolysis gas chromatography, which means that the seed polymerization proceeded well in view of the fact that the polymerization conversion rate of this polymerization was 75%. Is shown.

Example 2 Polyvinylpyrrolidone K-30 1.8 g, sulfosuccinic acid di-
2-ethylhexyl sodium 0.5g, styrene monomer
5.6 g, divinylbenzene 0.084 g and 2,2′-azobisisobutyronitrile 0.057 g were dissolved in a mixed medium of ethanol 74.9 g and cyclohexane 17.1 g, and polymerization was carried out at 70 ° C. for 8 hours under a nitrogen gas stream. . The polymerization conversion rate in this polymerization was 90%. Furthermore, when the polymer particles obtained by this polymerization were observed with a scanning electron microscope, the particle size was
It was confirmed that the spherical particles had a very high monodispersity of 1.2 μm and a standard deviation of 2.0%. Using this as a seed polymer, the following operation was performed.

First, 2,2'-azobis (2,4-dimethylvaleronitrile)
0.015 g, toluene 0.035 g, sodium alkyldiphenyl ether disulfonate "Perex SS-H" 2 x 10 ^-4 g
And 1 g of water were emulsified and finely dispersed so that the particle size of oil droplets was 0.5 μm or less. The dispersion obtained in the previous polymerization was 1.5
% Cross-linked particle size 1.2 μm Monodisperse polystyrene 1 g, sodium alkyldiphenyl ether sulfonate “Perex SS
-H "(0.01 g) and water (9 g) were added to the emulsified aqueous dispersion, and the dispersed oil droplets were absorbed by the seed polymer while slowly stirring at room temperature for 2 hours.

The aqueous dispersion of this seed polymer was then treated with sodium alkyldiphenyl ether sulfonate "Perex SS.
-H "was added to 50 g of a 0.1% aqueous solution, 4.4 g of styrene and 0.6 g of divinylbenzene were further added, and the mixture was slowly stirred at 30 ° C for 1 hour to allow the monomer to be absorbed by the seed polymer. Then, polymerization was carried out at 60 ° C. for 7 hours and 70 ° C. for 1 hour.

When the polymer particles obtained by the above polymerization were observed with a scanning electron microscope, it was confirmed that they were true spherical particles having a particle size of 2 μm and a standard deviation of 2.1% and having extremely high monodispersity. The degree of crosslinking of the obtained polymer particles was estimated by pyrolysis gas chromatography to be 9.0%, and the polymerization conversion rate of seed polymerization was 70%.

Example 3 Polyvinylpyrrolidone K-30 1.8 g, sulfosuccinic acid di-
2-ethylhexyl sodium 0.5g, styrene monomer
20g, divinylbenzene 0.12g and 2,2'-azobisisobutyronitrile 0.21g ethanol 35g and xylene 42g
Was dissolved in the mixed medium of and the polymerization was carried out at 70 ° C. for 8 hours in a nitrogen gas stream. The polymerization conversion rate in this polymerization was 85%. Furthermore, when the polymer particles obtained by this polymerization were observed with a scanning electron microscope, it was confirmed that they were true spherical particles having a particle diameter of 6.0 μm and a standard deviation of 2.3% and having extremely high monodispersity. Using this as a seed polymer, the following operation was performed.

First, 2,2'-azobis (2,4-dimethylvaleronitrile)
0.015 g, toluene 0.035 g, sodium alkyldiphenyl ether disulfonate "Perex SS-H" 2 x 10 ^-4 g
And 1 g of water were emulsified and finely dispersed so that the particle size of oil droplets was 0.5 μm or less. The dispersion obtained in the previous polymerization was 0.6.
% Cross-linked particle size 6.0 μm Monodisperse polystyrene 1 g, sodium alkyldiphenyl ether sulfonate "Perex SS
-H "(0.01 g) and water (9 g) were added to the emulsified aqueous dispersion, and the dispersed oil droplets were absorbed by the seed polymer while slowly stirring at room temperature for 2 hours.

The aqueous dispersion of this seed polymer was then treated with sodium alkyldiphenyl ether sulfonate "Perex SS-
31.6 g of 0.1% aqueous solution of "H" was added, 29.6 g of styrene and 2.0 g of divinylbenzene were further added, and the mixture was slowly stirred at 30 ° C for 1 hour to allow the monomer to be absorbed by the seed polymer. Then, polymerization was carried out at 60 ° C. for 7 hours and 70 ° C. for 1 hour.

When the polymer particles obtained by the above polymerization were observed with a scanning electron microscope, it was confirmed that they were true spherical particles having a particle size of 18 μm and a standard deviation of 2.6% and having extremely high monodispersity. The degree of cross-linking of the obtained polymer particles was estimated by pyrolysis gas chromatography to be 5.0%, and the conversion of seed polymerization was 80%.

Example 4 Polyvinylpyrrolidone K-30 1.8 g, sulfosuccinic acid di-
2-ethylhexyl sodium 0.5g, styrene monomer
Dissolve 12.5 g, divinylbenzene 0.08 g and 2,2'-azobisisobutyronitrile 0.13 g in a mixed medium of ethanol 72.5 g and cyclohexane 13 g, and under a nitrogen gas stream at 70 ° C.
Polymerization was carried out for 8 hours. The polymerization conversion rate in this polymerization is
It was 95%. Furthermore, when the polymer particles obtained by this polymerization were observed with a scanning electron microscope, the particle size was 2.0 μm.
It was confirmed that the spherical particles had extremely high monodispersity with m and standard deviation of 1.0%. Using this as a seed polymer, the following operation was performed.

First, 2,2'-azobis (2,4-dimethylvaleronitrile)
0.015 g, toluene 0.035 g, sodium alkyldiphenyl ether disulfonate "Perex SS-H" 2 x 10 ^-4 g
And 1 g of water were emulsified and finely dispersed so that the particle size of oil droplets was 0.5 μm or less. The dispersion obtained in the previous polymerization was 0.6.
% Cross-linked particle size 2.0 μm Monodisperse polystyrene 1 g, sodium alkyldiphenyl ether sulfonate “Perex SS
-H "(0.01 g) and water (9 g) were added to the emulsified aqueous dispersion, and the dispersed oil droplets were absorbed by the seed polymer while slowly stirring at room temperature for 2 hours.

Next, this aqueous dispersion of seed polymer was added to an aqueous solution of 0.02 g of polyvinylpyrrolidone K-30, 8 × 10 ^-3 g of di-2-ethylhexyl sulfosuccinate and 28 g of water, and 0.7 g of styrene and 2.1 g of divinylbenzene were further added. , 30 ℃
The mixture was slowly stirred for 1 hour to allow the monomer to be absorbed by the seed polymer. Then, polymerization was carried out at 60 ° C. for 7 hours and 70 ° C. for 1 hour.

When the polymer particles obtained by the above polymerization were observed with a scanning electron microscope, it was confirmed that they were true spherical particles having a particle size of 3.1 μm and a standard deviation of 1.5% and having extremely high monodispersity. The degree of crosslinking of the obtained polymer particles was estimated to be 43% by pyrolysis gas chromatography, and the polymerization conversion rate of seed polymerization was 78%.

Example 5 Polyvinylpyrrolidone K-30 1.8 g, styrene monomer 12.
5g, divinylbenzene 0.08g, glycidyl methacrylate
0.13 g and 0.13 g of 2,2'-azobisisobutyronitrile were dissolved in a mixed solvent of 60 g of ethanol and 25.4 g of cyclohexane, and polymerization was carried out at 70 ° C for 8 hours under a nitrogen gas stream. The polymerization conversion rate in this polymerization was 80%. In addition, when the polymer particles obtained by this polymerization were observed with a scanning electron microscope, it was confirmed that they were true spherical particles having a particle size of 4 μm and a standard deviation of 2.8% and having extremely high monodispersity. The operation was performed.

First, 2,2'-azobis (2,4-dimethylvaleronitrile)
0.015 g, toluene 0.035 g, sodium alkyldiphenyl ether disulfonate "Perex SS-H" 2 x 10 ^-4 g
And 1 g of water were emulsified and finely dispersed so that the particle size of oil droplets was 0.5 μm or less. This dispersion was prepared from the previous polymerization at 0.
6% cross-linked particle size 4 μm Monodisperse styrene-divinylbenzene-glycidyl methacrylate copolymer 1 g, sodium alkyldiphenyl ether disulfonate "Perex SS-
0.01 g of H "and 9 g of water were added to the emulsified aqueous dispersion, and the dispersed oil droplets were absorbed by the seed polymer while slowly stirring at room temperature for 2 hours.

Subsequently, the aqueous dispersion of this seed polymer was added to an aqueous solution of 0.02 g of polyvinylpyrrolidone K-30, 8 × 10 ^-3 g of di-2-ethylhexyl sulfosuccinate and 21 g of water, and 1.2 g of styrene and 0.92 of divinylbenzene. g was added, and the mixture was slowly stirred at 30 ° C. for 1 hour to allow the monomer to be absorbed by the seed polymer. Then, polymerization was carried out at 60 ° C. for 7 hours and 70 ° C. for 1 hour.

When the polymer particles obtained by the above polymerization were observed with a scanning electron microscope, it was confirmed that they were true spherical particles having a particle size of 5 μm and a standard deviation of 3.0% and having extremely high monodispersity. The degree of crosslinking of the obtained polymer particles was estimated by pyrolysis gas chromatography to be 24%, and the polymerization conversion rate of seed polymerization was 83%.

Example 6 The same polymerization as in Example 5 was carried out except that 0.13 g of 2- (N, N'-dimethyl) ethyl methacrylate was used instead of glycidyl methacrylate in Example 5.

The particle size of the obtained seed polymer, its standard deviation, the polymerization conversion rate, and the particle size of the polymer particles enlarged by seed polymerization, its standard deviation, the polymerization conversion rate, and the degree of crosslinking estimated by pyrolysis gas chromatography were measured. The results are shown in Table 1.

Example 7 The same polymerization as in Example 5 was carried out except that 0.13 g of chloromethylstyrene was used instead of glycidyl methacrylate in Example 5.

The particle size of the obtained seed polymer, its standard deviation, the polymerization conversion rate, and the particle size of the polymer particles enlarged by seed polymerization, its standard deviation, the polymerization conversion rate, and the degree of crosslinking estimated by pyrolysis gas chromatography were measured. The results are shown in Table 1.

Example 8 Polymerization was carried out in the same manner as in Example 5 except that 0.13 g of vinylbenzyl glycidyl ether was used instead of glycidyl methacrylate in Example 5.

The particle size of the obtained seed polymer, its standard deviation, the polymerization conversion rate, and the particle size of the polymer particles enlarged by seed polymerization, its standard deviation, the polymerization conversion rate, and the degree of crosslinking estimated by pyrolysis gas chromatography were measured. The results are shown in Table 1.

Example 9 Polyvinylpyrrolidone K-30 1.8 g, glycidyl methacrylate 12.5 g, ethylene glycol dimethacrylate 0.0
1 g and 2,3′-azobisisobutyronitrile (0.13 g) were dissolved in a mixed solvent of ethanol (73.0 g) and cyclohexane (12.5 g), and polymerization was carried out at 70 ° C. for 8 hours under a nitrogen gas stream. The polymerization conversion rate in this polymerization was 98%. Further, the polymer particles obtained by this polymerization were observed by a scanning electron microscope, and it was confirmed that the particles were spherical particles having a particle diameter of 1.6 μm and a standard deviation of 1.0% and having extremely high monodispersity. Using this as a seed polymer, the following operation was performed.

First, 0.36 g of 2,2'-azobisisobutyronitrile, 36.6 g of ethylene glycol dimethacrylate, 43.8 g of 1,2-dichloroethane, 0.66 g of sodium dodecyl sulfate and 280 g of water have an oil droplet particle size of 0.5 μm or less. Finely dispersed. This emulsion has a degree of crosslinking of 0.1% obtained in the previous polymerization, and is a monodisperse glycidyl methacrylate having a particle size of 1.6 μm.
Seed the oil droplets into an aqueous dispersion consisting of 5.0 g of ethylene glycol dimethacrylate copolymer, 0.01 g of sodium dodecyl sulfate and 124 g of water at room temperature over 2 hours, then stir slowly at the same temperature for 12 hours. Absorbed on polymer.

Next, 30.5 g of a 3% aqueous polyvinyl alcohol solution was added thereto, and polymerization was carried out at 70 ° C. for 8 hours in a nitrogen gas stream. The final polymerization conversion rate was 93%, and the particles were porous particles having a specific surface area of 10.50 m ² / g as measured by the BET method. When observed by a scanning electron microscope, the polymer particles obtained by this polymerization had a particle size of 3.2 μm and were extremely highly monodisperse with a standard deviation of 1.9%.

Example 10 Polyvinylpyrrolidone K-30 (Tokyo Kasei Co., Ltd., average molecular weight 40,000) 1.8 g, glycidyl methacrylate 12.5
g, ethylene glycol dimethacrylate 0.005 g and 2,
2'-azobisisobutyronitrile 0.13 g in ethanol 7
It was dissolved in a mixed solvent of 3.0 g and cyclohexane 12.5 g, and polymerization was carried out at 70 ° C. for 8 hours under a nitrogen gas stream. The polymerization conversion rate in this polymerization was 98%. Further, the polymer particles obtained by this polymerization had a particle size of 1.4 μm and a standard deviation of 1.0 when observed with a scanning electron microscope.
It was confirmed that the spherical particles had extremely high monodispersity of 100%. Using this as a seed polymer, the following operation was performed.

First, 2,2'-azobisisobutyronitrile 0.36 g, ethylene glycol dimethacrylate 32.9 g, glycerin monomethacrylate 3.7 g, 1,2-dichloroethane 43.8 g, sodium dodecyl sulfate 0.66 g and water 280 g oil droplets Diameter
Finely dispersed so as to have a particle size of 0.5 μm or less. This dispersion was 0.05% crosslinked and had a particle size of 1.4% obtained in the previous polymerization.
μm monodisperse glycidyl methacrylate / ethylene glycol dimethacrylate copolymer 5.0 g, 0.01 g of sodium dodecyl sulfate and 124 g of water were added dropwise to the aqueous dispersion at room temperature over 2 hours, and then the mixture was slowly stirred at that temperature for 12 hours. Meanwhile, the oil droplets were absorbed by the seed polymer.

Then add 3% polyvinyl alcohol and 30.5
g was added and polymerization was carried out at 70 ° C. for 8 hours in a nitrogen gas stream to obtain particles having a final polymerization conversion rate of 90%.

When observed by a scanning electron microscope, the polymer particles obtained by this polymerization had a particle size of 3.2 μm and were extremely highly monodisperse with a standard deviation of 2.0%.

Example 11 In the production of the seed polymer in Example 4, the same polymerization as in Example 4 was performed except that the amount of divinylbenzene used was 0.04 g instead of 0.08 g, and the particle size was 2.0 μm.
As a result, true spherical particles having a standard deviation of 1.0% and having extremely high monodispersity were obtained. Using this as a seed polymer, the following operation was performed.

First, 1.6 g of benzoyl peroxide, 158 g of toluene, 105 g of ethylene glycol dimethacrylate, 4.6 g of sodium dodecyl sulfate and 2000 g of water were finely dispersed so that the particle size of oil droplets was 0.5 μm or less. 260 g of the obtained dispersion liquid was obtained by the above polymerization, and the degree of crosslinking was 0.3%, and 1.5 g of monodisperse styrene-divinylbenzene copolymer having a particle size of 2.0 μm and sodium dodecyl sulfate.
To the aqueous dispersion containing 0.15 g and 15 g of water was added dropwise at 50 ° C. for 10 minutes, and the dispersed oil droplets were absorbed into the seed polymer while slowly stirring at that temperature for 1 hour.

Then add 3% polyvinyl alcohol and 220g aqueous solution
Was added thereto, and polymerization was carried out at 80 ° C. for 8 hours in a nitrogen gas stream to obtain a final conversion of polymerization of 90%, and the particles were porous particles having a specific surface area of 350 m ² / g as measured by the BET method.

When observed by a scanning electron microscope, the polymer particles obtained by this polymerization had a particle size of 4.0 μm and were extremely monodisperse with a standard deviation of 2.4%.

Application Example 1 10 g of the polymer obtained in Example 9 was replaced with 107 g of a 10% H ₂ SO ₄ aqueous solution.
In the medium, hydrolysis was carried out by heating at a temperature of 50 ° C. for 5 hours to open the ring of the glycidyl group in the polymer.

After the reaction was completed, the polymer was separated by filtration and sufficiently washed with demineralized water until the liquid became neutral to obtain a crosslinked acrylic resin having a hydroxyl group quantitatively.

5 g of 10 g of crosslinked acrylic resin obtained by the above hydrolysis
It was put into 21 g of an N-NaOH aqueous solution, and stirred at room temperature for 60 minutes under ultrasonic dispersion. Then, 28.6 g of 51% β-diethylaminoethyl chloride hydrochloride aqueous solution was added to this, and 50
Hold at 5 ° C for 5 hours. After the reaction was completed, the product was washed with 100 g of demineralized water and subsequently with 20 g of 1N-hydrochloric acid aqueous solution, and then thoroughly washed with demineralized water until the liquid became neutral to quantify the amount of the acrylic anion exchange resin having a diethylaminoethyl group. I got it.

The anion exchange resin manufactured with the above formulation has an exchange capacity of 0.58.
It was meq / g-resin.

The acrylic anion exchange resin having a diethylaminoethyl group produced as described above was separated by ion exchange chromatography using a gradient elution method of a mixed protein containing myoglobin, ovalbumin and a trypsin inhibitor as components.

The chromatogram is shown in FIG. 2, and the obtained chromatogram shows a good resolution.

The used apparatus for ion exchange chromatography by the gradient elution method was LC-6A system manufactured by Shimadzu Corporation. The measurement conditions are as shown below.

Measurement conditions Column: 7.5 mm ID x 75 mm Flow rate: 1.0 ml / min Dissolution: A → B 20 min Linear gradient A: 14 mmol-Trishydroxymethylaminomethane / hydrochloric acid buffer solution (pH 8.0) B: A + 0.5 mol sodium chloride Detection: UV 280nm Temperature: 25 ° C In addition, the pressure during liquid flow under these measurement conditions is 40kg / cm ²
Which is much lower than that of the conventional suspension polymerization method having a similar particle size.

In addition, the measurement of the exchange capacity of the obtained anion exchange resin,
The following method was used.

Approximately 2.0 g of anion exchange resin wet product was added to 20 ml of 1N-NaOH aqueous solution.
The mixture was put in and shaken at room temperature for 30 minutes. After this was filtered off, it was thoroughly washed with a pH 10 aqueous NaOH solution.

Next, the obtained anion exchange resin was dispersed in a 1% NaCl aqueous solution, and using an automatic titration operation (manufactured by Mitsubishi Kasei Kogyo Co., Ltd. GT-05) while stirring, a dropping rate of 0.05N-HCl aqueous solution was used. Titration was performed at 20 µl / sec to prepare a titration curve (Fig. 1). After the titration was completed, the anion exchange resin was filtered off, washed thoroughly with water, dried at 80 ° C. for 3 hours, and the mass was weighed.

In FIG. 1, the horizontal axis is the amount of drops, and the vertical axis is the titration curve representing pH, which is 0.0 up to the first inflection point (point of pH 8.0).
The amount of 5N-HCl aqueous solution added dropwise was Vml, the factor of 0.05N-HCl aqueous solution was f, and the dry anion exchange resin mass was Mg. The exchange capacity was represented by the following formula.

Application Example 2 10 g of the polymer obtained in Example 1 was added to 50 g of 1,2-dichloroethane, and the mixture was kept at a temperature of 80 ° C. for 5 hours and filtered.
The obtained polymer was added to 80 g of 98% H ₂ SO _{4 and the} mixture was kept at 80 ° C. for 8 hours for sulfonation. After completion of the reaction, reduce the concentration of H ₂ SO _{4 in} the system to 30% or less with demineralized water, and add 10% N
A ₂ CO ₃ aqueous solution was added to neutralize the inside of the system. Then add 2% N
After adding 20 g of aClO aqueous solution and thoroughly stirring, the obtained resin was kept in water at 95 ° C. for 5 hours to quantitatively obtain a styrene-based cation exchange resin having a sulfone group.

The exchange capacity of the ion exchange resin manufactured with the above formulation is 4.0 meq.
It was / g.

The styrene-based cation-exchange resin having a sulfone group produced here was used as an ion-exchange chromatograph using an isocratic elution method in which the eluent of mixed amino acids containing aspartic acid, serine, glutamic acid and glycine and other elution conditions were not changed during measurement. A chromatographic separation was performed.

The elution time of each amino acid was aspartic acid 15 minutes, serine
A chromatogram showing good resolution was obtained at 18 minutes, glutamic acid 22.5 minutes and glycine 29 minutes.

The LC-3A system manufactured by Shimadzu Corporation was used as an apparatus for ion exchange chromatography by the isocratic elution method. The measurement conditions are as shown below.

Measurement conditions Column: 4.6 mm ID x 150 mm Flow rate: 0.5 mm / ml Dissolution: Isocratic sodium citrate buffer Reaction: Sodium hypochlorite-OPA Detection: Fluorescence method (Ex.360 nm, Em.450 nm) ) Temperature: 60 ° C Application Example 3 10 g of the polymer obtained in Example 10 was added to 100 g of a 10% H ₂ SO ₄ aqueous solution.
The glycidyl group in the polymer was ring-opened by holding the mixture in the medium at 50 ° C. for 3 hours and performing hydrolysis.

After completion of the reaction, the polymer was separated, and demineralized water was used to sufficiently wash the filtrate until the filtrate became neutral to quantitatively obtain a crosslinked acrylic resin having a hydroxyl group.

10 g of cross-linked acrylic resin obtained by the above hydrolysis
Was added to 50 g of toluene and 0.7 g of epibromhydrin, and the mixture was stirred for 30 minutes at room temperature under ultrasonic dispersion.
Then, hydrous p-toluenesulfonic acid monohydrate was added thereto.
2 g was added and the reaction was carried out at 70 ° C. for 2 hours. The reaction product was filtered, washed with methanol, and air-dried at room temperature for 1 hour to obtain a reaction product having a 2-hydro-3-bromopropyl group.

10 g of the reaction product obtained above was put into 50 g of a methanol solution of tetramethyldiaminopropane 0.1 mmol / ml, and the reaction was carried out at 60 ° C. for 3 hours. The reaction product was filtered, washed with methanol, and air-dried at room temperature for 1 hour to obtain a tertiary resin.
The total amount of this resin is a methanol solution of methyl iodide 1 mmol / ml.
Put in 50g, react at 30 ℃ for 16 hours with shaking,
Quaternization was performed to quantitatively obtain an acrylic anion exchange resin.

The exchange capacity of the ion exchange resin manufactured with the above formulation is 50 μeq
It was / g-resin.

Using the acrylic anion exchange resin having a quaternary ammonium group produced here, ion chromatography of mixed anions of fluoride ion, nitrite ion, nitrate ion, bromine ion, chloride ion and sulfate ion was performed. The chromatogram is shown in FIG. A chromatogram with good sensitivity and resolution was obtained. A Shimadzu LC-6A system was used as the ion exchange chromatography device. The measurement conditions are as shown below.

Measurement conditions Column: 5.0 mm ID x 50 mm Flow rate: 1.0 ml / min Dissolution: 0.5 mmol Disodium phthalate Detection: UV 260 nm Indirect absorbance detection Temperature: 25 ° C Application Example 4 Polymer particles obtained in Example 11 To the column,
Separation of phthalates by reversed-phase chromatography using the isocratic elution method was performed.

The elution time of each ester was dimethyl phthalate (3.6 minutes), diethyl phthalate (4.4 minutes), and dibutyl phthalate (8.0 minutes), and a chromatogram showing a good resolution was obtained.
The measurement conditions are shown below.

Measurement conditions Column: 7.0mm ID × 75mm Flow rate: 0.8ml / min Dissolution: Isocratic 65v / v% acetonitrile aqueous solution Detection: UV 254nm Temperature: 25 ℃ [Effect of the invention] According to the present invention, the first stage Since the particle size of the seed polymer obtained in (1) is large, the degree of enlargement in seed polymerization can be reduced. That is, the amount of the polymerizable monomer to be absorbed with respect to the seed polymer is 50% by volume with respect to the particles.
As a result, it is possible to impregnate the particles with a polymerization initiator and a polymerizable monomer in an extremely short time as compared with existing methods, and to obtain a monodisperse crosslinked polymer particle having an extremely good quality. It can be reliably manufactured. Further, in the present invention, since a cross-linked polymer is used as the seed polymer, it is possible to produce gel-type polymer particles, and further, in order to form an interpenetrating network, a similar effect can be obtained with a cross-linking degree lower than the usual cross-linking degree. In addition, the physical strength of the particles can be increased. Further, since the degree of enlargement of the seed polymer can be reduced, the property can be reflected in the enlarged particles.

The polymer particles produced by the method of the present invention have a degree of crosslinking of 0.5-9.
It is a polymer particle having 8%, a particle size of 1 to 30 μm, an arbitrary degree of crosslinking and a particle size, and a narrow particle size distribution.

The polymer particles obtained by the method of the present invention have various chromatographic carriers, standard samples for microscopic examination, separation, fluid flow, centrifugation, diffusivity measurement, model system materials such as dust research, and biomedical diagnostics. Medicinal carrier,
Immobilized enzyme carrier, powder ink, electrostatic development toner, paint, powder lubricant, sensitive layer improving material, microcapsule,
Spacer material for protecting microcapsules of pressure-sensitive copying paper,
Examples include spacers for liquid crystal cells, plastic pigments for coated papers, plastic pigments for adhesives, binders for ceramics, base polymer particles for impact-resistant resins, and plastic pigments for cosmetics, which are extremely useful in various fields.

In particular, the resin of the present invention is used as a carrier for liquid chromatography, for example, a carrier for amino acid analysis, a protein separating agent, a carrier for ion chromatography, a polymer-based reverse phase carrier and the like.

Further, when the polymer particles obtained in the present invention are used as a carrier for chromatography, due to the uniformity of particle diameter,
It gave excellent separation characteristics.

[Brief description of drawings]

FIG. 1 is a titration curve, and FIGS. 2 and 3 are diagrams showing chromatograms. 1 ... Myoglobin 2 ... Ovalbumin 3 ... Trypsin inhibitor

Claims (2)

[Claims] 1. A crosslinked polymer particle is produced by polymerizing a polymerizable monomer containing a crosslinkable monomer in a medium in which a polymerizable monomer is dissolved in a first step but a produced polymer is not dissolved, In the method for producing crosslinked polymer particles, the obtained crosslinked polymer particles are allowed to absorb a polymerizable monomer containing a crosslinkable monomer and then polymerized. 2. In the second step, the amount of the polymerizable monomer to be absorbed by the crosslinked polymer particles is determined by the volume of the particles.
50 times or less, The manufacturing method of the crosslinked polymer particle of Claim 1 characterized by the above-mentioned.