JPS6026405B2 - Manufacturing method of bead-shaped polymer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a bead-shaped cationic high molecular weight water-soluble polymer having excellent water-removal properties.

Water-soluble high molecular weight polymers obtained by polymerizing monomers containing neutralized salts or quaternized dialkylaminoalkyl (meth)acrylates can be used as flocculants, as yield improvers for various fillers during paper manufacturing, and as pulp additives. It is an important polymer used for purposes such as recovery and fiber processing.
In recent years, it has been used in large quantities as a dehydration accelerator for excess sludge generated in activated sludge treatment facilities of human waste treatment plants, chemical and food factories, and is now occupying an important position as a wastewater treatment agent. When a cationic water-soluble polymer is used as a flocculant, the higher the molecular weight, the greater the effect.

The method for producing a water-soluble polymer obtained by polymerizing a monomer containing a neutralized salt or a quaternized product of dialkylaminoalkyl (meth)acrylate is a method for producing a water-soluble polymer obtained by a general radical mechanism such as polyacrylamide. Manufacturing methods can be used. That is, examples include aqueous solution polymerization, precipitation polymerization, and suspension polymerization. When using an aqueous solution polymerization method, in order to obtain a high molecular weight polymer, polymerization is carried out at a monomer concentration of 1% by weight or more, so the product becomes a water-containing rubber-like substance that is slow to dissolve and difficult to transport. It must be crushed and dried to form a powder. Furthermore, since it is difficult to control the polymer during polymerization, it is difficult to remove the heat of polymerization, so the molecular weight in the middle part of the reaction system decreases significantly and the product tends to be non-uniform. When using the precipitation polymerization method, a homogeneous powdery polymer can be easily obtained, but it is necessary to use an extremely polar solvent that dissolves the neutralized salt of dialkylaminoalkyl (meth)acrylate and the quaternary ammonium salt compound. It is necessary to make Hakozawa.

In this case, chain transfer during polymerization is large and it is difficult to obtain a high molecular weight polymer. Also, products tend to be differentiated.
On the other hand, suspension polymerization is an advantageous polymerization method that can easily obtain high molecular weight polymers in powder form because of its large heat removal effect. As described in 37-15033, a nonionic emulsifier is used in an inert dispersion medium to polymerize an aqueous monomer solution as a water-in-oil or oil-in-water emulsion. This method dialkylaminoalkyl (meth)
When used in the polymerization of monomers containing neutralized salts or quaternized acrylates, the salting-out effect of this compound makes it difficult to form emulsions.

Even if an emulsion is formed under appropriate conditions, such as by significantly lowering the concentration of the aqueous polymer solution, the polymer obtained by drying after polymerization tends to become a fine powder. When a finely powdered water-soluble polymer is dissolved in water, it contains air bubbles and the dissolution rate becomes extremely slow. In addition, it becomes dust during the melting process and deteriorates the working environment. In producing a water-soluble polymer obtained by polymerizing a neutralized salt or quaternized product of dialkylaminoalkyl (meth)acrylate, or a monomer containing these, the present inventors have developed the above method while maintaining the characteristics of the suspension polymerization method. As a result of intensive research on how to avoid these problems and supply products in a preferred form, we have discovered that by using a specific dispersion stabilizer, it is possible to carry out suspension polymerization of the above monomers at any aqueous solution concentration. We have completed a method to obtain extremely high-molecular-weight polymers with good solubility in the form of uniform beads that do not contain any particles.

This method also allows suspension polymerization of highly concentrated monomer aqueous solutions, in which case the dehydration operation is significantly improved or even eliminated, significantly streamlining the polymer production process. That is, the present invention provides a method for producing a water-soluble bead-like polymer by polymerizing an aqueous solution of a water-soluble vinyl monomer in a dispersion chamber in the presence of a dispersion stabilizer. ) (RI represents a hydrogen atom or a methyl group, R2 and R3
may be the same and represent a straight chain or branched alkyl group having 1 to 4 carbon atoms, R4 is a hydrogen atom, a straight chain or branched alkyl group having 1 to 8 carbon atoms, or a hydroxy-substituted alkyl group having 1 to 4 carbon atoms. and penzyl group, and Y represents an alkylene group having 2 to 4 carbon atoms or a hydroxy-substituted alkylene group.

×e indicates an anion. ) or 'b} A monomer mixture of the compound of the above general formula (1) and another water-soluble pinyl monomer that can be copolymerized with (1) is used, and ethyl hydroxyethylcellulose is used as a dispersion stabilizer. The present invention relates to a method for producing a bead-shaped polymeric characterized by using the following.

The present invention will be explained in more detail below.

The neutralized salt or quaternary ammonium salt compound of dialkylaminoalkyl (meth)acrylate of the present invention has the following general formula (1) (where RI represents a hydrogen atom or a methyl group, R2 and R3 may be the same, and carbon a straight or branched alkyl group of numbers 1 to 4, R4 is a hydrogen atom, a straight or branched alkyl group having 1 to 8 carbon atoms, a hydroxy-substituted alkyl group having 1 to 4 carbon atoms, and a penzyl group; One selected group is shown, and Y represents an alkylene group having 2 to 4 carbon atoms or a hydroxy-substituted alkylene group.

×e is C, halogen ion such as Br, sulfate ion,
It refers to anions such as nitrate ion, phosphate ion, carboxylate ion, sulfonate ion, and alkyl sulfate ion having an alkyl group having 1 to 8 carbon atoms. ) is a compound represented by. For example, dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate,
Diethylaminoethyl acrylate, diethylaminoethyl methacrylate, dibutylaminoethyl acrylate, dibutylaminoethyl methacrylate, etc. and hydrochloric acid,
Neutralized salts with acids such as sulfuric acid, nitric acid, phosphoric acid, acetic acid, propionic acid, benzenesulfonic acid, and 8-methacryloyloxyethyltrimethylammonium chloride, 8
-methacryloyloxyethyltrimethylammonium methyl sulfate, 3-methacryloyloxyethyldimethylethyl ammonium bromide, 8-methacryloyloxyethyldimethylammonium monoethyl sulfate, 8-methacryloyloxyethylbenzylammonium chloride, 8-acryloyloxyethyltrimethylammonium Chloride, 8-acryloyloxyethyltriethylammonium bromide, 2
Examples include quaternized products such as -hydroxy-3-methacryloyloxypropyltrimethylammonium chloride. The cationic high-molecular-weight water-dropping polymer that is the object of the present invention is composed of a neutralized salt or a quaternary salt of dialkylaminoalkyl (meth)acrylate represented by the general formula (1), and It is a homopolymer or a copolymer with a water-soluble monomer such as acrylamide or methacrylamide containing at least 5 mol % of neutralized salt or quaternary dry matter as a constituent unit of the polymer.

Ethylhydroxyethylcellulose, which is used as a dispersion stabilizer, is usually alkali cellulose with ethylene oxide 'hydroxyethylation and ethyl chloride'.
It is a mixed cellulose ether obtained by such ethylation, and has the property of being soluble in a wide range of organic solvents.

The compound used as a dispersion medium can be a compound that dissolves ethyl hydroxyethyl cellulose but does not dissolve the aqueous solution of the monomer. However, if a chain saturated hydrocarbon with a boiling point of 35 to 40 pi is used, dispersion is particularly difficult. Good stability.

Ethyl hydroxyethyl cellulose does not dissolve in chain saturated hydrocarbons at room temperature, but it dissolves under heating conditions of chain saturated hydrocarbons with boiling points ranging from 35 to 18 pi○, so this chain saturated hydrocarbon is used alone. In this case, a polymerization system with good dispersion stability can be prepared by dispersing the monomer aqueous solution at 55° C. or higher. Further, in such a case, heating may be performed under pressurized conditions if necessary. As the boiling point of the chain saturated hydrocarbon used as the dispersion medium increases, the temperature at which ethyl hydroxyethyl cellulose is dissolved increases.If the chain saturated hydrocarbon has a boiling point of 18~0 or higher, it will not dissolve even if heated to 1000℃. If a chain saturated hydrocarbon is used alone, the boiling point is 35.
It is preferable to use one having a temperature of 180°C to 180°C. On the other hand, if a chain saturated hydrocarbon is mixed with a compound that dissolves ethylhydroxyethyl cellulose at room temperature, the boiling point is 35-40.
Any chain saturated hydrocarbon in the range of 0 to 0 can be used as a dispersant.

Examples of compounds that dissolve ethylhydroxyethylcellulose at room temperature include esters, ketones, halogenated alkyls, ethers, alcohol aromatic hydrocarbons, halogenated aromatic hydrocarbons, and aliphatic hydrocarbons. If a compound that dissolves ethylhydroxyethyl cellulose at room temperature is mixed with a chain saturated hydrocarbon having a boiling point of 35 to 180 qo, conditions for good dispersion stability can be obtained even at room temperature.

In addition, if a compound that dissolves ethylhydroxyethyl cellulose at room temperature is mixed with a chain saturated hydrocarbon having a boiling point of 180 to 400, good conditions for dispersion stability can be obtained at room temperature or under heating conditions, depending on the amount mixed. It will be done. The chain saturated hydrocarbon having a boiling point of 35 to 180 oo is a straight chain or branched saturated hydrocarbon, and specific examples thereof include pentane, hexane, heptane, octane, /nane, decane, and mixtures thereof. Boiling point 180~
400oo chain saturated hydrocarbons include undecane, dodecane, tetradecane, octadecane, tetracosane,
Examples include bentatriacontane and mixtures thereof.

Further, petroleum fractions containing chain saturated hydrocarbons having a boiling point of 35 to 4000 C can also be used in the same manner as the saturated hydrocarbons described above.

If the chain saturated hydrocarbon has high purity, it will show the same properties as the chain saturated hydrocarbon, and if it contains aromatic hydrocarbons and alicyclic hydrocarbons, these compounds will be mixed with the chain saturated hydrocarbon. It shows the same properties as when it is used as dispersed soot. Petroleum fractions used as dispersants include petroleum distillate,
These include ligroin, kerosene, and liquid paraffin. Compounds that dissolve ethylhydroxyethyl cellulose at room temperature, such as esters, ketones, alkyl halides, ethers, alcohols, aromatic hydrocarbons, halogenated aromatic hydrocarbons, and alicyclic hydrocarbons, include the following: Can be mentioned.

The ester is preferably an ester of an aliphatic carboxylic acid having 1 to 8 carbon atoms or an aromatic carboxylic acid having 7 to 8 carbon atoms and an alkali/alkyl having 1 to 8 carbon atoms or an alkoxy-layered alkanol. For example, methyl acetate, ethyl acetate, n-propyl acetate, isobropyl acetate, n-butyl acetate, isobutyl acetate, t-butyl acetate, phenyl acetate, pendyl acetate, methoxyethyl acetate, poxyethyl acetate, methyl propionate, ethyl propionate,
These include methyl butyrate, butyl butyl, tertyl cyanate, methyl caproate, methyl caprylate, methyl benzoate, ethyl benzoate, n-butyl benzoate, dimethyl phthalate, diethyl phthalate, dibutyl phthalate, and the like. Among the above esters, esters of aliphatic carboxylic acids and alkanol or alkoxy-substituted alkanols are preferred.

As the ketone, an aliphatic ketone having a total of 3 to 8 carbon atoms or an aromatic ketone having a total of 8 to 13 carbon atoms is preferable.

For example, acetone, methyl ethyl ketone (MEK), methyl-n-propyl ketone, diethyl ketone, cyclobentanone, methyl butyl ketone, methyl isobutyl ketone (MIBK), cyclohexanone, methyl amyl ketone, dipropyl ketone, hexyl methyl ketone, acetophenone, penzophenone, etc. be. The halogenated alkyl is a halogenated alkyl having 1 to 6 carbon atoms, preferably a halogenated alkyl having 1 to 4 carbon atoms.

For example, methylene chloride, carbon tetrachloride, 1,2-dichloroethane, 1,1,2-trichloroethane, 1,1
, 2,2-tetrachloroethane, bentachloroethane 1
, 2-dichloropropane, 1,2-dibromoethane, 1
, 1,2-tripromethane, 1,2-dipromopropane, 1,2-dibromobutazo, and the like. As the ether, straight mirror or cyclic ethers having 4 to 8 carbon atoms are preferred.

Examples include di-n-propyl ether, di-n-butyl ether, tetrahydrofuran, dioxane, diethylene glycol dimethyl ether, and the like. As the alcohol, alkanols having a total of 2 to 8 carbon atoms or alkoxy-substituted alkanols are preferred.

Examples include ethanol, n-propanol, n-butanol, n-octanol, methoxyethanol, ethoxyethanol, butoxyethanol, diethylene glycol mo/methyl ether, and the like. The aromatic hydrocarbon or halogenated aromatic hydrocarbon is preferably a compound having 6 to 8 carbon atoms.

Examples include benzene, toluene, xylene, ethylbenzene, monochlorobenzene, dichlorobenzene, monoprombenzene, and diprombenzene. The alicyclic hydrocarbon is preferably an alicyclic hydrocarbon having 5 to 10 carbon atoms or an alkyl-substituted alicyclic hydrocarbon compound.

Examples include cyclobentane, cyclohexane, cyclohebutane, methylcyclohexane, cyclooctane, decalin, and the like. When these compounds that dissolve ethylhydroxyethylcellulose at room temperature are mixed with a chain saturated hydrocarbon, it is preferable to mix them within the following range. The ester, ketone, alkyl halide, ether, and alcohol to be mixed with the chain saturated hydrocarbon are preferably used in an amount within 0.3 times the weight of the chain saturated hydrocarbon.

The aromatic hydrocarbon and halogenated aromatic hydrocarbon to be mixed with the chain saturated hydrocarbon are preferably used in an amount equal to or less than the weight of the chain saturated hydrocarbon. The amount of alicyclic hydrocarbon to be mixed with the chain saturated hydrocarbon is preferably within 1 ph to the weight of the chain saturated hydrocarbon. If added in an amount exceeding the above-mentioned range, dispersion stability tends to deteriorate. The method for using the dispersion medium has been described above, but since a polymerization system with extremely good dispersion stability can be prepared by using such a dispersion medium, there is no need to perform an operation to match the specific gravity of the aqueous monomer solution and the dispersion soot. It is possible to obtain bead-shaped polymers with uniform particle size.

Another feature of the present invention is that an inexpensive dispersion medium can be used. The amount of ethylhydroxyethylcellulose, which is a dispersion stabilizer, added is 0.05 to 10% by weight, preferably 0.5 to 5% by weight, based on the dispersed soot.

The dispersion medium is used in an amount of 0.5 to 1" weight, preferably 1 to 6 times the weight of the aqueous monomer solution containing the compound of general formula (1).

The concentration of the monomer aqueous solution can be arbitrarily selected within the range of 1% by weight to 9% by weight.

When polymerized at concentrations greater than 6% by weight, the products are simple. It can be obtained as a bead-shaped product by performing a dehydration operation or by simply removing the dispersed soot without dehydration at all.

When polymerizing at a monomer concentration of 6% by weight or less, a bead-shaped product can be obtained as is, but the product can also be obtained by dehydrating the water in the polymer using methods such as boiling water dehydration, solvent dehydration, and heat drying. can. In this case, even if dehydration is performed,
The bead-like morphology remains unchanged. Although the polymerization method of the present invention is not limited to the order of addition of the dispersant, dispersion medium, monomer aqueous solution, and radical polymerization initiator, the following method is best for obtaining a granular and uniform polymer.

After nitrogen gas is passed through the dispersed soot in which the dispersion stabilizer has been dissolved to remove oxygen, an aqueous monomer solution containing a radical polymerization initiator is added to the dispersed soot which has been deoxidized and brought to a predetermined temperature while being dispersed. General radical polymerization initiators such as peroxides and azo compounds are used as polymerization initiators.
Particularly preferred are water-soluble polymerization initiators.

Examples of water-soluble polymerization initiators include peroxides such as ammonium persulfate, potassium persulfate, peracetic acid, and hydrogen peroxide;
,2'-azobis-2-amidinopcopane hydrochloride, 4,
Examples include azo compounds such as 4'-azobis-4-cyanobentanoic acid. When a peroxide is used as an initiator, polymerization can be carried out using a redox-based initiator in combination with a reducing agent such as sodium metasulfite, sodium sulfite, or ferrous chloride, if necessary. The polymerization temperature can be from 4000℃ to the boiling temperature of the dispersion medium, but to obtain a high molecular weight polymer it is 50℃ to 70℃.
It is desirable to polymerize at a temperature of °C.

Although the conditions vary depending on the shape of the screw and the size of the reaction tank, it is preferable to conduct the process so that the droplet size of the monomer aqueous solution dispersed in the dispersion medium is about 0.01 to 1.

0 However, according to the present invention, by using ethyl hydroxyethyl cellulose as a dispersion stabilizer, a polymer with excellent solubility and extremely high molecular weight can be prepared in a uniform particle size of 0.05 to 1 skin without any powdery particles. It can be manufactured in the form of beads.

Next, the present invention will be specifically explained with reference to Examples, but the present invention is not limited to these Examples unless the gist thereof is exceeded.

Examples 1 to 15 A 200cc 4-unit separable flask equipped with a cooling pipe, a nitrogen introduction pipe, a dropping funnel, and a fluorine-free resin wing was charged with ethyl hydroxyl dispersion media of 100 and 3 times as shown in Table 1. Ethylcellulose (manufactured by Hercules, EHEC)
(Product name) Grade Mountain w) will be introduced.

While deoxidizing through nitrogen gas, the temperature is increased to 60°C. Fifty minutes of an 80% aqueous solution of P-methacryloyloxyethyltrimethylammonium chloride and one hour of a 10% aqueous solution of 2,2'-azopis-2amidinopropane hydrochloride as a polymerization initiator were introduced into the dropping funnel. Pass nitrogen gas through. Under concentrated conditions of 200* to 25 pm, the MonoJmer aqueous solution in the dropping funnel was added dropwise and kept at 60° C. under nitrogen atmosphere for 1 hour, and the product was taken out.

The results are shown in Table 1. Table 1 Examples 16-19 Except for using ethyl hydroxyethyl cellulose as a dispersant and dissolving it in the dispersion medium shown in Table 2 under heating conditions x*, and then polymerizing at the polymerization temperature shown in Table 2. Examples 1-1
Polymerization was carried out under exactly the same conditions as in Example 5.

The results are shown in Table 2. Table 2 Examples 20 to 22 The reaction was carried out under the same conditions as in Example 16, except that the type of monomer, monomer aqueous solution concentration, and polymerization initiator concentration were changed as shown in Table 3.

The results are shown in Table 3. Table 3 AAM: Acrylamide DMAEMA-MC: Coumethacryloyloxyethyltrimethylammonium chloride D background 1/noble H2s
o4; Somelaminoethyl methacrylate example Isohoru Nakatenme 1* The pH of the aqueous solution was 6.

Claims (1)

[Claims] 1. In a method for producing a water-soluble vinyl monomer by polymerizing an aqueous solution of a water-soluble vinyl monomer in a dispersion medium in the presence of a dispersion stabilizer, as the water-soluble vinyl monomer, (A)
The following general formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (R^1 represents a hydrogen atom or a methyl group, R^2 and R^3 may be the same, and are Indicates a branched alkyl group, R^4 is a hydrogen atom, and has 1 or more carbon atoms.
Y represents one group selected from the group consisting of a straight chain or branched alkyl group having 8 carbon atoms, a hydroxy-substituted alkyl group having 1 to 4 carbon atoms, and a benzyl group, and Y is an alkylene group having 2 to 4 carbon atoms or a hydroxy-substituted alkyl group. Indicates an alkylene group. X■ represents an anion. ) or (B) using a monomer mixture of the compound of general formula (I) above and another water-soluble vinyl monomer that can be copolymerized with (I), and using ethylhydroxyethylcellulose as a dispersion stabilizer. A method for producing a bead-shaped polymer characterized by: 2. In a method for producing a water-soluble bead-shaped polymer by polymerizing an aqueous solution of a water-soluble vinyl monomer in a dispersion medium in the presence of a dispersion stabilizer, as the water-soluble vinyl monomer (
A) General formula (I) below ▲ Numerical formulas, chemical formulas, tables, etc. Indicates a chain or branched alkyl group, R^4 is a hydrogen atom, and has 1 or more carbon atoms
Y represents one group selected from the group consisting of a straight chain or branched alkyl group having 8 carbon atoms, a hydroxy-substituted alkyl group having 1 to 4 carbon atoms, and a benzyl group, and Y is an alkylene group having 2 to 4 carbon atoms or a hydroxy-substituted alkyl group. Indicates an alkylene group. X■ represents an anion. ) or (B) using a monomer mixture of the compound of the above general formula (I) and another water-soluble vinyl monomer that can be copolymerized with (I), and using ethyl hydroxyethyl cellulose as a dispersion stabilizer and dispersion. A method for producing a bead-like polymer, characterized in that a chain saturated hydrocarbon having a boiling point of 35 to 400°C is used as a medium.