JP3482984B2 - Method for producing hydroxyl group-containing porous resin - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a hydroxyl group-containing porous resin. The hydroxyl group-containing porous resin obtained by the present invention is a material useful as a column packing material, various adsorbents, carriers, etc., and is a material more useful as a functional porous resin after being chemically modified. obtain.

[0002]

2. Description of the Related Art Conventionally, porous materials have been used as packing materials for analytical or preparative columns, carriers for enzymes, catalysts, useful substances, and various adsorption carriers by making use of their structural and chemical properties. It has been researched and developed for various uses and fields for many years. Representative examples thereof include inorganic materials such as porous silica gel and alumina, and synthetic polymer materials such as divinylbenzene-styrene porous resin and divinylbenzene-methacrylic acid ester porous resin.

Porous silica gel has excellent mechanical strength, and is used for column packing and solid phase extraction by itself or in the form of chemically modifying various functional groups and useful substances by utilizing its surface silanol groups. It is widely used as a substrate and immobilized catalyst, but it has problems due to the chemical stability inherent to silica gel, such as stability in basic media and the effect of residual silanol groups [eg, journals・ Chromatographic Science (J. Chromat
ogr. Sci. ) Vol. 22, 386 (1984),
Journal of Chromatography (J. Chro
matgr. ) Vol. 149, p. 199 (1978)].

On the other hand, the basic production method of the divinylbenzene-styrene type porous resin is generally well known. For example, it is involved in a monomer mixture containing divinylbenzene and styrene, a polymerization initiator, and a polymerization reaction. It is obtained by subjecting a monomer solution mixed with an organic solvent, which is poorly soluble in water and is insoluble in water and in which the monomer mixture is soluble but not the copolymer obtained from it, to an aqueous medium [for example, Journal of. Applied Polymer Science (J. Appl. Polym. Sc
i. ) Vol. 23, p. 927 (1979), Angewante Macromolecula Chemi (Angew. Makrom).
ol. Chem. ) Vol. 80, p. 31 (1979)]. Generally, in this type of ordinary suspension polymerization, apparent particles (hereinafter referred to as secondary particles) have a diameter of 50 μm to 2 m.
A porous resin of about m is obtained.

In addition, as a step of dispersing or suspending the monomer solution in an aqueous medium before the polymerization, a step (hereinafter referred to as a microsuspension step) carried out under high-speed stirring using a homogenizer or a homomixer is adopted. In the case of turbid polymerization, the diameter of secondary particles is usually 0.5 to
A porous resin of about 50 μm can be obtained. In addition, as a step of dispersing or suspending the monomer solution in the aqueous medium before the polymerization, the aqueous solution containing the anionic or nonionic surfactant is passed through the porous glass membrane having a uniform pore size. For suspension polymerization that employs a process performed by press-fitting (hereinafter referred to as a film emulsification process), a porous resin having secondary particles having a diameter of about 0.3 to 100 μm and a very uniform particle size is used. can get.

In any of these methods, when the surface or inside of the obtained secondary particles is observed using an electron microscope or the like, fine particles having a size of about 10 to 100 nm (hereinafter referred to as primary particles) It can be seen that the particles are strongly aggregated. That is, the gap between the agglomerated primary particles and the primary particles is a space in which the organic solvent was present during the polymerization, and the primary particles themselves are almost free from the high-order crosslinked resin. It is insoluble in the organic solvent, and basically does not swell.

Such a divinylbenzene-styrene type porous resin makes use of the excellent mechanical strength and chemical stability of its resin matrix, introduces a functional group on or near the surface of the primary particles, and is useful. As a so-called functional porous resin in which a substance is chemically modified to impart new functionality, it is attracting attention in various applications and fields. The following two methods are basically known as methods for introducing a functional group: (i) an aromatic ring moiety of the synthesized divinylbenzene-styrene-based porous resin and a residual vinyl group; Method of introducing various functional groups by utilizing the chemical reaction of (ii)
A method in which, in addition to divinylbenzene and styrene monomers, a monomer having a desired functional group (hereinafter referred to as a functional group-containing monomer) is preliminarily mixed, and this is polymerized. However, in the method (i), the chemical reaction is essentially solid.
Since it is carried out between liquids, it has various drawbacks such that it is often subjected to extreme reaction conditions, the reaction conversion rate is extremely poor, and the secondary particles are destroyed during the reaction. Also in the method (ii), it is difficult to efficiently arrange and orient the functional group portion of the used functional group-containing monomer on or near the surface of the primary particle.
Most of the functional group-containing monomers exist inside the region of the monomer mixture, and as a result, the functional group sites are embedded inside the crosslinked resin matrix, which has the drawback that the function cannot be fully exerted. There is. That is, the higher the degree of cross-linking by divinylbenzene, the more the swelling property of the primary particles with respect to the solvent is extremely reduced. This drawback becomes a serious problem in designing and synthesizing the functional porous resin. come.

[0008]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a porous resin in which functional groups are efficiently arranged and oriented on the surface of primary particles or in the vicinity thereof.

[0009]

In view of the importance of technological development of functional porous resins or functional group-containing porous resins, the inventors of the present invention should overcome the drawbacks of the conventional production methods as described above. In particular, the inventors focused their attention on the problem of the arrangement and orientation of the resin containing the functional group-containing monomer on the surface of the primary particles of the above (ii), and conducted intensive studies. As a result, a vinylbenzyloxyalkyl ester derivative represented by the following general formula (1) having a strong affinity or a portion having a strong affinity for an organic solvent is used as a functional group-containing monomer in a suspension polymerization which has been conventionally performed. If present, the derivative is predominantly present in the vicinity of the interface between the “polymer + monomer” and “organic solvent” regions during polymerization, and the derivative is present on or near the surface of the primary particles of the resulting resin. The inventors have found that the ester groups derived from the derivative are aligned and oriented, and thus reached the present invention.

That is, the present invention relates to divinylbenzene and the general formula (1):

[0011]

[Chemical 2]

(Wherein n represents an integer of 2 to 16 and R represents an alkyl group having 1 to 4 carbon atoms), a monomer mixture containing a vinylbenzyloxyalkyl ester derivative, a polymerization initiator, Also, a monomer solution obtained by mixing with an organic solvent that does not participate in the polymerization reaction, is sparingly soluble in water, and dissolves the monomer mixture but does not dissolve the copolymer obtained therefrom is dispersed or suspended in an aqueous medium. The present invention relates to a method for producing a hydroxyl group-containing porous resin, which comprises polymerizing in a turbid state and then hydrolyzing an ester portion of the obtained resin.

In the present invention, divinylbenzene-styrene in which hydroxyl groups derived from the vinylbenzyloxyalkyl ester derivative represented by the general formula (1) are efficiently arranged and oriented on or near the surface of the primary particles of the resin. The present invention provides a simple method for producing a hydroxyl group-containing porous resin.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The raw material, polymerization step and hydrolysis step of the method for producing a hydroxyl group-containing porous resin of the present invention will be described in detail below.

The monomer mixture used in the polymerization of the present invention is
It contains divinylbenzene and a vinylbenzyloxyalkyl ester derivative represented by the general formula (1).

As the divinylbenzene, commercially available divinylbenzene having a purity of about 50 to 60%, which is generally available, may be used as it is, or may be used after being purified by distillation. It contains about 50-40% ethyl vinyl benzene as an impurity. Of course, if it is available, a high purity one may be used without any problem. Divinylbenzene mainly has meta and para isomers, but in the present invention, it may be a mixture of these isomers or each isomer alone.

The vinylbenzyloxyalkyl ester derivative represented by the general formula (1) may be a mixture of meta and para isomers, or each isomer alone. In addition, n in the formula is an integer of 2 to 16. When n is less than 2, the arrangement / orientation of ester groups on the resin surface is lowered, and when n is more than 16, the polymerization rate is lowered and the specific surface area of the obtained resin is lowered, which is preferable. Absent. From these points, n is preferably an integer of 4 or more, and more preferably 12 or less. The portion of the alkylene chain of the vinylbenzyloxyalkyl ester derivative represented by the general formula (1) is generally called a spacer and plays an important role in the affinity with an organic solvent such as a hydrocarbon solvent or an ester solvent. Is responsible for

The vinylbenzyloxyalkyl ester derivative represented by the general formula (1) can be produced by a known method [for example, Journal of American Chemical Society (J. Am. Chem.
Soc. ) 112: 6723 (1990)]. That is, the general formula (2):

[0018]

[Chemical 3]

(Wherein n represents an integer of 2 to 16) is treated with sodium hydride or the like to give an alkoxide, which is subsequently reacted with vinylbenzyl chloride to give a compound of the general formula (3):

[0020]

[Chemical 4]

A vinylbenzyloxyalkanol represented by the formula (1) is obtained, and then the obtained vinylbenzylalkanol represented by the formula (3) is easily reacted with an aliphatic carboxylic acid or an anhydride thereof to obtain the formula (1). ) A vinylbenzyloxyalkyl ester derivative can be obtained. Vinylbenzyl chloride is usually available as a mixture of meta and para isomers, but in the present invention, it may be used as a mixture as it is. Of course, each of the meta or para isomers may be used alone. In addition, the vinylbenzylalkanol represented by the general formula (3) improves the reaction selectivity to the target substance by appropriately selecting the charged molar stoichiometric ratio of alkyldiol, sodium hydride and vinylbenzyl chloride. be able to.

In the vinylbenzyloxyalkyl ester derivative represented by the general formula (1), the ester group increases the hydrophobicity of the derivative, and the affinity with the organic solvent to be used becomes strong. It is expected to bring further effect to the alignment and orientation in the vicinity of the interface between “polymer + monomer” and “organic solvent”. When vinylbenzyloxyalkanol represented by the general formula (3) is used as it is (without being esterified) as a functional group-containing monomer for suspension polymerization similar to the present invention, the reaction system sometimes becomes It was observed that the particles became unstable and agglomeration of secondary particles occurred, or the specific surface area of the obtained resin was considerably decreased. This esterification in the present invention also has an important meaning because the problem of this kind is solved by using the vinylbenzyloxy ester derivative represented by the general formula (1) as the functional group-containing monomer.

The content of the divinylbenzene and the vinylbenzyloxyalkyl ester derivative represented by the general formula (1) contained in the monomer mixture is determined based on the total weight of the monomers of 100% by weight. Usually, the content of the vinylbenzyloxyalkyl ester derivative represented by the general formula (1) in the monomer mixture is 3 to 30.
It is about% by weight, and contains divinylbenzene and the like as the balance. The vinylbenzyloxyalkyl ester derivative represented by the general formula (1) introduces an ester group, which is a functional group, that is, a hydroxyl group obtained by hydrolysis, onto the resin surface or in the vicinity thereof. It is 3% by weight or more of the total weight. Particularly, 5% by weight or more is preferable. Further, since the decrease in the polymerization rate and the decrease in the surface area of the obtained resin can be suppressed, the content of the derivative is
It is preferably 30% by weight or less based on the total weight of the monomers.
Further, according to the production method of the present invention, the used general formula (1)
75% or more of the vinylbenzyloxyalkyl ester derivative represented by can be arranged and oriented on or near the surface of the primary particle of the resin (in the general formula (1), n is 4
In the case of the above vinylbenzyloxyalkyl ester derivative), in other words, the amount that can be arranged and oriented on or near the surface of the primary particle is limited in terms of space.
It can be said that the use of up to 30% by weight of the total weight of the monomers is sufficient to obtain the desired hydroxyl group-containing porous resin.

Further, the monomer mixture may contain an aromatic monovinyl monomer. As the aromatic monovinyl monomer, styrene, methylstyrene, ethylvinylbenzene, etc. can be used.
Use more than one seed. These may be commercially available products or may be distilled and purified. Methylstyrene includes meta-, para-, α- and β-
, Etc., but in the present invention, a mixture of these isomers may be used, or each isomer may be used alone. Also, ethyl vinyl benzene is
Although there are meta and para isomers, in the present invention,
It may be a mixture of these isomers or each isomer alone. Furthermore, in the case of ethyl vinyl benzene, since it is contained in a predetermined amount in commercially available divinyl benzene, it is usually used as it is, but of course, if it is available, it is newly added and used. Good.

Even when the monomer mixture contains an aromatic monovinyl monomer, the content of the vinylbenzyloxyalkyl ester derivative represented by the general formula (1) is about 3 to 30% by weight, and the remainder is divinyl. It contains about 15 to 97% by weight of benzene and about 0 to 82% by weight of an aromatic monovinyl monomer. When the content of divinylbenzene is less than 15% by weight, the specific surface area of the obtained resin is reduced, which is not preferable. From this point of view, the content of divinylbenzene is preferably 20% by weight or more.
The aromatic monovinyl monomer content is 82% by weight or less from the viewpoint of mechanical strength of the obtained resin. Usually, the monomer mixture often contains 5% by weight or more of an aromatic monovinyl monomer, but in this case, the upper limit of the content of divinylbenzene is 92% by weight.

The polymerization initiator is not particularly limited as long as it is soluble in the above-mentioned monomer mixture. Examples thereof include organic peroxides such as benzoyl peroxide and lauryl peroxide, and azo compounds such as azobisisobutyronitrile. The amount of the polymerization initiator used is within an arbitrary range depending on the required physical properties of the resulting porous resin and the like, but normally it is preferably about 0.5 to 5% by weight based on the total weight of the monomers.

The organic solvent to be mixed with the above-mentioned monomer mixture is one that does not participate in the polymerization reaction, is hardly soluble in water, and dissolves the monomer mixture but does not dissolve the copolymer obtained therefrom. With such an organic solvent, the function as a so-called porous solvent can be sufficiently exhibited.

As such an organic solvent, in order to more effectively align and orient the hydroxyl groups on the surface of the primary particles of the resulting porous resin or in the vicinity thereof, the organic solvent represented by the above general formula (1) is used. An organic solvent having a good affinity with the vinylbenzyloxyalkyl ester derivative described above is preferable. For example,
Examples thereof include hydrocarbon solvents having 6 to 12 carbon atoms and ester solvents having 4 to 10 carbon atoms. Specifically, hexane, heptane, octane, nonane, decane, dodecane and other aliphatic hydrocarbon solvents, ethyl acetate, propyl acetate, butyl acetate, pentyl acetate, hexyl acetate, heptyl acetate, ethyl propionate, propyl propionate And aliphatic ester solvents such as butyl propionate and hexyl propionate. Of course, the aliphatic hydrocarbon portion of the organic solvent exemplified above may be linear or branched.
Further, these organic solvents may be used alone or in combination of two or more kinds. The mixing ratio of the organic solvent and the monomer mixture can be mixed in an arbitrary range depending on the required physical properties of the resulting porous resin, etc., but usually, the volume ratio of the organic solvent / monomer mixture is 70/30 to 25 /.
It is preferable to mix within the range of 75.

The process itself in the suspension polymerization of the present invention is no different from the conventional suspension polymerization and can be carried out by a known method. For example, a monomer solution obtained by uniformly mixing the monomer mixture, the polymerization initiator and the organic solvent,
It can be carried out by a generally-used suspension polymerization method in which the material is dispersed or suspended in an aqueous medium with stirring, and heated for polymerization. A suitable dispersion stabilizer may be contained in the aqueous medium. The dispersion stabilizer is not particularly limited as long as it can stably disperse the monomer solution in the form of droplets in the aqueous medium, but generally well-known polyvinyl alcohol, polyacrylamide, polyacrylic acid, gelatin, etc. The water-soluble polymer of is mentioned. The amount used is not particularly limited as long as a monomer droplet having a target particle size can be stably obtained. The amount of the dispersion stabilizer may be adjusted in consideration of the next polymerization step, that is, the monomer droplets may be polymerized without causing coalescence / aggregation.

The amount ratio of the monomer solution to the aqueous medium is not particularly limited as long as the dispersion step and the polymerization step can be carried out without any problem, but from the industrial point of view, usually, the volume ratio of the monomer solution / aqueous medium is usually monomer solution / aqueous medium. = 1/10 to 1/2 is preferable. The polymerization temperature and the polymerization time in the polymerization step are not particularly limited, but appropriate conditions may be selected in consideration of the decomposition temperature and half-life of the polymerization initiator, the boiling point of the organic solvent and the like. Further, the type of the polymerization reaction vessel and the stirring method are not limited as long as the monomer droplets can be stably polymerized without coalescence / aggregation. Further, similarly to general suspension polymerization, an inorganic dispersant such as the above water-soluble polymer or colloidal silica may be added to suppress coalescence / aggregation of monomer droplets during polymerization. The type and amount used are not particularly limited. This general suspension polymerization method is effective when the target secondary particle diameter of the porous resin is required to be about 50 μm to 2 mm.

The secondary particle size of the desired porous resin is
When about 0.5 to 50 μm is required, a suspension polymerization method including a microsuspension step before polymerization is effective. Microsuspension step, for example, the monomer mixture, a polymerization initiator and an organic solvent uniformly mixed monomer solution, in an aqueous medium containing a suitable dispersant stabilizer, high-speed stirring using a homomixer or a homogenizer. However, it can be carried out by a method of once finely dispersing.

The stirring speed in the microsuspension step depends on various conditions such as the amount ratio of the organic phase composed of the monomer solution and the aqueous phase containing the dispersion stabilizer, the kind and concentration of the dispersion stabilizer, and the like. Usually 1 to 1 using a homogenizer
When adjusting on a 5 L scale, 1000-30000r
When it is performed in the range of pm, the characteristics of the homogenizer can be sufficiently exhibited. Even when a microsuspension step is included before the polymerization, the same polymerization conditions as the conventionally known suspension polymerization method can be applied as they are.

The secondary particle diameter of the resulting porous resin is 0.
When it is required that the particle size distribution is about 3 to 100 μm and the particle size distribution is very sharp, a suspension polymerization method including a film emulsification step before polymerization is extremely effective. That is, before polymerization, a step of dispersing or suspending the monomer solution by press-fitting it into an aqueous medium containing an anionic or nonionic surfactant through a porous glass membrane having a uniform pore size, Suspension polymerization including. A conventionally known method can be applied as it is to the film emulsification step itself before the polymerization.

The porous glass membrane used in the membrane emulsification step may be a glass membrane having uniform pores with an average pore diameter of about 0.1 to 10 μm. In particular, a glass film prepared from Shirasu porous glass is excellent in the uniformity of pores and is preferable in the present invention. When a porous glass membrane having an average pore size of less than 0.1 is used, it takes a long time to emulsify the membrane, which is not preferable from the viewpoint of industrial production. Also, the average pore diameter is 10μ.
When a glass film having a size larger than m is used, it becomes very difficult to obtain emulsified droplets having a uniform particle size, which is also not preferable when secondary particles having a uniform particle size are desired. That is, if the glass membrane having an average pore diameter of about 0.1 to 10 μm is used, the emulsified droplets obtained by membrane emulsification usually have a particle diameter of about 3 to 10 times the pore diameter of the glass membrane. Moreover, the particle size distribution is very sharp.

In the film emulsification step, the pressure at which the organic phase composed of the monomer solution is pressed into the aqueous phase through the glass film is such that the desired emulsified droplets are obtained and are not deformed or destroyed. There is no particular limitation as long as it is within the range, but normally, the critical pressure (here, the minimum pressure at which the organic phase can pass through the pores of the glass membrane is meant) is 1.05-1.
When the pressure is about 5 times, emulsified droplets having a very sharp particle size distribution can be stably obtained with good operability. The temperature at the time of film emulsification is not particularly limited as long as it is a temperature at which film emulsification can be stably performed and polymerization does not start, but it is usually 0 to 60 ° C.

As the surface active agent used in the aqueous phase at the time of membrane emulsification, anionic surface active agents such as sodium alkylsulfate, sodium alkylbenzenesulfonate and sodium alkylsulfosuccinate, polyoxyethylene alkyl ether, polyethylene glycol fatty acid ester, etc. The nonionic surfactant, etc. may be used, and the amount thereof may be any amount as long as the organic phase can stably exist as emulsified droplets during the film emulsification step, but usually the concentration in the aqueous phase is It is preferably about 0.05 to 2% by weight.

After the membrane emulsification step, the process proceeds to the polymerization step. In order to prevent the emulsified droplets from coalescing and agglomerating during the polymerization, the dispersion stability of the water-soluble polymer often used in ordinary suspension polymerization The agent may be used in combination. Of course, it is not necessary to use a dispersion stabilizer such as a water-soluble polymer when the reaction proceeds stably without coalescence / aggregation of the emulsion droplets during the polymerization. When a dispersion stabilizer is used, it may be contained in the aqueous phase from the time of the film emulsification step or added at the time of the polymerization step. Examples of the water-soluble polymer include generally well-known polyvinyl alcohol, polyacrylamide, polyacrylic acid, gelatin, and the like.
There is no particular limitation as long as the emulsified droplets can be stably dispersed in the required particle size. The amount of water used as the aqueous phase in the present invention is not limited at all, and may be any amount as long as the steps of membrane emulsification and polymerization can be carried out smoothly, and it may be the same as in ordinary suspension polymerization. Even when a film emulsifying step is included before the polymerization, the same polymerization conditions as those of the conventionally known suspension polymerization method can be applied as they are.

In any of the above-mentioned general suspension polymerization, suspension polymerization including a microsuspension step before polymerization, and suspension polymerization including a film emulsification step before polymerization, the resin obtained by polymerization is There is no limitation on the method of isolation, washing and drying, and it can be carried out as follows, for example.
The resin obtained by the polymerization is filtered off by an appropriate method, washed well with hot water to remove the surfactant and the dispersion stabilizer adhering to the resin, and then an unreacted monomer and an organic solvent which is a porosifying solvent. In order to remove the resin, it is sufficiently washed with acetone, methanol or the like, and then dried by heating under reduced pressure to obtain an ester group-containing porous resin.

Hydrolysis of the ester moiety of the ester group-containing porous resin can be easily carried out under both conditions of a general acid catalyst and alkali catalyst. Examples of the acid catalyst include hydrochloric acid and sulfuric acid, and examples of the alkali catalyst include sodium hydroxide and potassium hydroxide. Hydrolysis is sufficiently possible with water alone as a solvent, but the dispersibility of the ester group-containing porous resin is good when used in combination with an alcohol solvent such as methanol or ethanol or a water-soluble ether solvent such as tetrahydrofuran. Progress well. The mixing ratio of the water / alcohol solvent, the water / ether solvent, etc. and the amount of the solvent are not limited as long as the ester group-containing porous resin is well dispersed and the hydrolysis proceeds. The reaction temperature and reaction time for hydrolysis are not particularly limited, and appropriate conditions may be selected in consideration of the boiling point of the solvent used, the reaction rate, and the like.

The method of washing and drying the resin after hydrolysis is not particularly limited as long as it can remove the catalyst and solvent used in the reaction sufficiently. For example, the obtained resin can be filtered off, washed well with hot water and methanol, and then dried by heating under reduced pressure to obtain the desired hydroxyl group-containing porous resin.

The hydroxyl group-containing porous resin thus obtained is subjected to general physical property evaluations such as specific surface area, primary and secondary particle diameters, and chemical properties such as hydroxyl value and functional group orientation ratio (%). It can be characterized by performing physical property evaluation. That is, the amount of hydroxyl groups capable of reacting in the resin can be known from the hydroxyl value. The functional group orientation rate (%) is
“Amount of total ester groups based on the vinylbenzyloxyalkyl ester derivative represented by the general formula (1) used for polymerization” exists on or near the surface of the primary particle,
The "amount of ester group involved in hydrolysis" indicates the proportion of "the amount of ester group present on or near the surface of the primary particles and involved in hydrolysis" as used herein. The hydroxyl value of the hydroxyl group-containing porous resin finally obtained by the hydrolysis treatment can be obtained and converted from it.

The hydroxyl group-containing porous resin obtained by the production method of the present invention usually has a high surface area of 50 m ² / g or more, a functional group orientation rate of 75% or more, and 5 to 60 mg KO.
It has a hydroxyl value of H / g. Further, the hydroxyl group-containing porous resin of the present invention has secondary particles having a spherical appearance and opacity, and the particle size thereof is 50 μm in the case of ordinary suspension polymerization.
m to 2 mm, 0.5 to 50 μm in the case of suspension polymerization including a microsuspension step, and 0.3 to 100 μm in the case of suspension polymerization including a membrane emulsification step. Again 1
The size of the secondary particles is usually 10 to 1 in any method.
It is about 00 nm.

The hydroxyl group-containing porous resin obtained by the production method of the present invention has a resin matrix of divinylbenzene-
Since it is a styrene-based resin, it has excellent mechanical strength and chemical stability. Of course, it is a material useful as a column packing material, various adsorbents, and carriers, but it is also useful as a material for or near the resin surface. It is possible to chemically perform secondary modification with various functional groups and functional substances using hydroxyl groups, and it is very useful as a functional porous resin. Furthermore, since the hydroxyl group exists from the polymer main chain through the alkyl spacer, it is considered that the inherent reactivity of the hydroxyl group can be sufficiently exhibited, and this secondary modification can be easily performed.

[0045]

EFFECT OF THE INVENTION According to the production method of the present invention, a hydroxyl group-containing porous resin in which hydroxyl groups are efficiently arranged and oriented on or near the surface of the primary particles can be obtained. Further, since the hydroxyl groups can be efficiently arranged and oriented on the surface of the primary particles or in the vicinity thereof, the amount of the vinylbenzyloxyalkyl ester derivative represented by the general formula (1) can be suppressed to the necessary minimum amount.

[0046]

EXAMPLES The present invention will be specifically described with reference to the following examples.

Example 1 300 equipped with a stirrer, a thermometer, a nitrogen introducing tube and a cooling tube
150 ml of ion-exchanged water was charged into a ml separable flask, and 3.0 g of polyvinyl alcohol (Poval-210: manufactured by Kuraray Co., Ltd.) was added and dissolved. Subsequently, divinylbenzene (content (purity) 55%, remaining 4
5% is ethyl vinylbenzene) 16.47 g, styrene 8.24 g, vinylbenzyloxyhexyl acetate (a compound of the general formula (1) in which n is 6 and R is a methyl group) 2.
A monomer mixture solution consisting of 75 g, 13.68 g of n-heptane and 0.549 g of azobisisobutyronitrile (2.0 wt% of the total amount of monomers) was added, and the mixture was stirred under a nitrogen stream at a stirring speed of about 400 to 500 rpm. The mixture was stirred for 10 minutes, the temperature was raised to 75 to 80 ° C., and polymerization was carried out for 6 hours while maintaining this temperature. After the polymerization, the mixture was cooled to room temperature, and the obtained resin was separated by filtration, washed well with hot water first and then with acetone, and then reduced pressure (about 1 mm).
/ Hg) and dried (70-80 ° C.) to obtain 25.5 g of resin. Next, in a 500 ml round-bottomed flask equipped with a magnetic stirrer, a thermometer, and a condenser tube, water 1
Charge 50 ml, 150 ml of ethanol, 6.0 g of sodium hydroxide and 25.5 g of the resin obtained above,
The mixture was heated and stirred at 85 to 90 ° C for 20 hours. After the reaction, the resin is separated by filtration, first washed well with hot water and then with acetone, and finally heated under reduced pressure (about 1 mm / Hg) (70 to 80 ° C).
It was dried to obtain 25.0 g of a porous resin. 2 of this resin
The secondary particle diameter is 210 μm in volume average particle diameter dv, 185 μm in number average particle diameter dn, and average primary particle diameter is 44 n.
m, specific surface area is 203 m ² / g, and hydroxyl value is 17.
It was 1 mg KOH / g.

Examples 2 to 5 Polymerization and hydrolysis were carried out in the same manner as in Example 1 except that the charged amount of each monomer or the kind or charged amount of the organic solvent was changed as shown in Table 1. Decomposition was performed to obtain a hydroxyl group-containing porous resin.

Example 6 Ion-exchanged water (160) was added to a 300 ml separable flask.
ml, 0.40 g of polyvinyl alcohol
(Poval-210: manufactured by Kuraray Co., Ltd.) was added and dissolved. Subsequently, divinylbenzene (content (purity) 55
%, The remaining 45% is ethyl vinyl benzene) 13.18
g, 6.59 g of styrene, 2.20 g of vinylbenzyloxyhexyl acetate (a compound of the general formula (1) wherein n is 6 and R is a methyl group), 10.94 g of n-heptane and 0.439 g of azobisisobutyronitrile. (2.0% by weight of the total amount of monomer)
About 10,000r using a homogenizer (made by IKA)
Dispersed for 5 minutes at a stirring speed of pm. Then replace with a normal stirrer, set the thermometer, nitrogen introduction tube and cooling tube,
This dispersion was heated to 75 to 80 ° C. while stirring at about 400 to 500 rpm under a nitrogen stream, and polymerization was carried out for 6 hours while maintaining this temperature. After the polymerization, the reaction mixture was cooled to room temperature, and the obtained resin was filtered off, washed well with hot water first, then with methanol and acetone, and then heated under reduced pressure (about 1 mm / Hg) (70 to 80 ° C.). ) Dried, 2
0.2 g of resin was obtained. Next, in a 500 ml round bottom flask equipped with a magnetic stirrer, a thermometer and a condenser, 150 ml of water, 150 ml of ethanol, 6.0 g of sodium hydroxide and 20.2 g of the resin obtained above were charged, and the temperature was 85 to 90 ° C. The mixture was heated and stirred for 20 hours. After the reaction, the resin was filtered off, washed thoroughly with hot water and then with acetone, and finally heated under reduced pressure (about 1 mm / Hg) (70 to 8 mm).
After drying at 0 ° C., 19.7 g of a porous resin was obtained. The secondary particle diameter of this resin is 6.79 μ in terms of volume average particle diameter dv.
m, the number average particle diameter dn is 6.16 μm, and the primary particle diameter is
The average was 42 nm, the specific surface area was 221 m ² / g, and the hydroxyl value was 16.9 mgKOH / g.

Example 7 Polymerization and hydrolysis were carried out in the same manner as in Example 6 except that the type or charged amount of each monomer or organic solvent was changed as shown in Table 1, and the hydroxyl group content was changed. A porous resin was obtained.

Example 8 Divinylbenzene (content (purity) 55%, balance 45%)
Is ethyl vinyl benzene) 51.39 g, styrene 2
5.69 g, vinylbenzyloxyhexyl acetate (a compound of the general formula (1) in which n is 6 and R is a methyl group) 8.
56 g, 42.68 g of n-heptane and 1.713 g of azobisisobutyronitrile (2.0 wt% of the total amount of the monomers) were uniformly mixed to prepare an organic phase 1 composed of a monomer solution. In addition, 12.6 of polyvinyl alcohol (Poval-224: made by Kuraray) was added to 630 ml of ion-exchanged water.
g, and 1.26 g of sodium dodecyl sulfate were added to prepare an aqueous phase 2 composed of an aqueous medium dissolved therein. The prepared organic phase 1 and aqueous phase 2 were respectively charged into the organic phase tank 3 and the aqueous phase tank 4 of the membrane emulsification device (manufactured by Ise Chemical Industry Co., Ltd.) shown in FIG. The water phase 2 is circulated in the water phase line 6 using the circulation pump 11, and then the organic phase 1 is provided in the circulating water phase line 6 at a pressure of 0.63 kgf / cm ² using nitrogen gas. Further, the aqueous phase 2 was pressed into the aqueous phase 2 through the porous glass membrane 8 having an average pore diameter of 0.70 μm in the double ring module 7 to emulsify the membrane to obtain an emulsion. Membrane emulsification is 12
0 ml (100 g) of organic phase 1 was pressed in over a period of two and a half hours and was terminated there. In addition, the film emulsification is based on
And the temperature of the aqueous phase 2 was maintained at 25 to 30 ° C. Next, 730 g of the emulsion obtained above was charged into a 1 L separable flask, a stirrer, a thermometer, a nitrogen introducing pipe and a cooling pipe were set, and the mixture was heated to about 400 to 400 in a nitrogen stream.
While stirring at 500 rpm, raise the temperature to 75-80 ° C,
Polymerization was carried out for 6 hours while maintaining this temperature. After the polymerization, the mixture was cooled to room temperature, and the obtained resin was separated by filtration, washed well with hot water first, then with methanol and acetone, and then heated under reduced pressure (about 1 mm / Hg) (70 to 80 mm).
(° C.) and dried to obtain 53.3 g of resin. Next, 500ml equipped with magnetic stirrer, thermometer, cooling tube
In a round bottom flask of 150 ml of water and 150 m of ethanol
1, 6.0 g of sodium hydroxide and the resin 2 obtained above
5 g was charged, and the mixture was heated and stirred at 85 to 90 ° C. for 20 hours.
After the reaction, the resin was separated by filtration, first washed well with hot water and then with acetone, and finally dried under reduced pressure (about 1 mm / Hg) by heating (70 to 80 ° C.) to obtain 24.3 g of a porous resin. Got The secondary particle diameter of this resin was 5.08 μm in volume average particle diameter dv, 5.01 μm in number average particle diameter dn, and particle size distribution dv / dn was 1.014, which was highly monodisperse. The average primary particle diameter is 42 nm, the specific surface area is 215 m ² / g, and the hydroxyl value is 17.2 mgKOH.
/ G.

Examples 9 to 11 Examples 9 to 11 were carried out except that the charged amount of each monomer or the charged amount of the organic solvent was changed as shown in Table 1 and the film emulsification conditions were changed as shown in Table 2. Polymerization and hydrolysis were carried out in the same manner as in Example 8 to obtain a hydroxyl group-containing porous resin.

[0053]

[Table 1]

[0054]

[Table 2]

Various physical properties of the resins obtained in the respective examples are shown in Table 3.
And shown in Table 4.

[0056]

[Table 3]

[0057]

[Table 4]

Various physical properties of the resin obtained in each example were measured by the following methods.

Primary particle size (nm): 100 from the scanning electron microscope (Hitachi, "S-2000") photograph
The number average particle size was calculated by measuring the size of at least one primary particle.

Secondary particle diameter (μm): arbitrary 500 from scanning electron microscope (Hitachi, "S-2000") photograph
The volume average particle diameter d is measured by measuring the size of at least two secondary particles.
v, number average particle size dn, and dv / d as a measure of particle size distribution
n was calculated.

Specific surface area (m ² / g): Measured using a BET surface area measuring device (“NOVA1200” manufactured by Counterchrome Co., Ltd.).

Hydroxyl value (mgKOH / g): The neutralization titration method (JIS K 0070) was modified as follows. Weigh 1g of resin into a flat bottom flask,
Acetylating reagent (25 g of acetic anhydride was placed in a 100 ml volumetric flask and pyridine was added to make 100 ml,
2.5 ml and pyridine 2.5
ml was added and heated in an oil bath at 60 ° C. for 2 hours. next,
This is cooled to room temperature, 1 ml of water is added, and the ultrasonic bath 80
The mixture was heated at ℃ for 1 hour to decompose acetic anhydride. After cooling, the inner wall of the flask was washed with 5 ml of ethanol, a few drops of phenolphthalein solution was added as an indicator, and titrated with 0.5 mol / l potassium hydroxide ethanol solution to obtain a hydroxyl value (mgK
OH / g) was calculated.

In the divinylbenzene-styrene type resin such as the porous resin of the present invention, the primary particles are crosslinked to a higher degree, and therefore acetylation under the above conditions results in the surface of the primary particles or the surface thereof. It progresses in the vicinity and hardly penetrates into the inside of the particles to react. Therefore, it can be assumed that the hydroxyl value measured above is based on the hydroxyl groups existing on or near the surface of the resin (primary particles).

Functional group orientation rate (%): Calculated by the following formula.

[0065]

[Equation 1]

Here, the amount of ester groups involved in the hydrolysis of the surface of the resin (primary particles) and its vicinity, that is, the amount of the hydroxyl groups after hydrolysis is calculated by the following formula from the above hydroxyl value. .

[0067]

[Equation 2]

The theoretical amount of ester groups based on the vinylbenzyloxyalkyl ester derivative represented by the general formula (1) used was calculated by the following formula.

[0069]

[Equation 3]

[Brief description of drawings]

FIG. 1 is a schematic view of a film emulsification device used in Examples 8 to 11.

[Explanation of symbols]

1 ... Organic phase 2 ... water phase 3 ... Organic phase tank 4 ... Water phase tank 5: Organic phase line 6 ... Water phase line 7: Double ring module 8 ... Porous glass membrane 9 ... Nitrogen gas line 10 ... Pressure gauge 11 ... Circulation pump 12 ... Nitrogen gas cylinder

─────────────────────────────────────────────────── --Continued from the front page (56) References JP-A-6-157674 (JP, A) JP-A-60-106802 (JP, A) JP-A-60-32803 (JP, A) International Publication 97/036950 (WO, A1) International Publication 96/028484 (WO, A1) (58) Fields investigated (Int.Cl. ⁷ , DB name) C08F 8/00-8/50

Claims (5)

(57) [Claims] 1. Divinylbenzene and general formula (1): (In the formula, n represents an integer of 2 to 16, and R represents 1 to 4 carbon atoms.
Is an alkyl group. ) A monomer mixture containing a vinylbenzyloxyalkyl ester derivative represented by (4), a polymerization initiator, and an organic compound which does not participate in the polymerization reaction and is hardly soluble in water and the monomer mixture is soluble but the copolymer obtained therefrom is insoluble. A monomer solution obtained by mixing with a solvent is polymerized in a state of being dispersed or suspended in an aqueous medium, and then a hydroxyl group-containing porous resin characterized by hydrolyzing an ester moiety of the obtained resin. Manufacturing method. 2. The monomer mixture further contains an aromatic monovinyl monomer.
The manufacturing method described. 3. The method according to claim 1 or 2, wherein the organic solvent is at least one of a hydrocarbon solvent having 6 to 12 carbon atoms and an ester solvent having 4 to 10 carbon atoms. . 4. The method according to claim 1, 2 or 3, wherein the step of dispersing or suspending the monomer solution in an aqueous medium is carried out by rapidly stirring the monomer solution using a homogenizer or a homomixer. Manufacturing method. 5. A step of dispersing or suspending a monomer solution in an aqueous medium, wherein the monomer solution is an aqueous system containing an anionic or nonionic surfactant through a porous glass membrane having a uniform pore size. The manufacturing method according to claim 1, 2 or 3, which is carried out by press-fitting into a medium.