JPH08337618A - Sulfonated conjugated diene polymer - Google Patents

Abstract

PURPOSE: To obtain a sulfonated conjugated diene polymer having strongly acidic sulfonyl groups, a high ion exchange capacity and a high molecular weight and being useful as e.g. a dispersant, an emulsifier or a water treating agent by specifying its structure. CONSTITUTION: This sulfonated conjugated diene polymer mainly consists of at least one kind of repeating units selected from among the repeating units of formulas I-III (wherein R<1> to R<6> are each H, a 1-8 C alkyl; a 6-20 C aryl; SO3 X(wherein X is H, an alkali (alkaline earth) metal; ammonium or amino), provided at least one of them is SO3 X) and has a weight-average molecular weight of 500-5,000,000. This polymer is obtained by polymerizing a sulfonate represented by formula IV. This sulfonate can be obtained for example by sulfonating a conjugated diene with a sulfur trioxide sulfonating agent.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a water-soluble or hydrophilic conjugated diene sulfonated polymer.

[0002]

2. Description of the Related Art Conventionally, a water-soluble and / or hydrophilic monomer has a carboxyl group-containing monomer such as acrylic acid or methacrylic acid, or a sulfoxyl group such as allylsulfonic acid or vinylsulfonic acid. Monomers are known. Further, regarding the sodium salt, potassium salt, and lithium salt of the monomer,
It is known that radical polymerization is possible. These monomers are widely industrially produced as water-soluble polymers or hydrophilic polymers by themselves or by copolymerizing with other monomers. For example, polyacrylic acid is used as a dispersant for calcium carbonate, or partially crosslinked to be used as a water-absorbent gel.

Also, many examples are known in which other vinyl monomers are copolymerized with acrylic acid or methacrylic acid for the purpose of modifying rubber or resin. Further, in the modification of latex, copolymerization of acrylic acid and methacrylic acid is also performed. However, these acidic monomers such as acrylic acid and methacrylic acid are weakly acidic although they are rich in radical polymerizability, and the resulting polymer has a drawback that it has weak emulsifying power when used as a surfactant. Have On the other hand, vinyl sulfonic acid, allyl sulfonic acid, or methacryl sulfonic acid obtained by reacting isobutylene with sulfur trioxide is a vinyl monomer having a strongly acidic sulfonyl group, and its polymer is strongly acidic. Although it has excellent emulsifying power, it has a drawback that the monomer itself is poor in radical polymerizability, so that only a polymer having a low polymer yield and a low molecular weight can be obtained.

On the other hand, styrene-based monomers such as sodium p-styrenesulfonate [eg Tosoh Corporation]
Manufactured, spiromer], or general formula A monomer having a sulfonyl group such as a methacrylic acid ester-based monomer represented by (for example, Eleminol RS-30 manufactured by Sanyo Kasei Co., Ltd.) has also been developed. These monomers are strongly acidic and have excellent radical polymerizability, but the monomer has a large molecular weight, a small number of sulfonyl groups per unit weight, and moreover, the synthesis route undergoes multiple steps. The manufacturing process is complicated and the cost is high. Therefore, the ion exchange capacity of the obtained polymer is low, the industrial productivity is poor, the cost is high, and the intended use is naturally limited.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of these problems of the prior art. A polymer having a sulfonyl group showing strong acidity, a large ion exchange capacity and a high molecular weight is provided. The purpose is to provide.

[0006]

The present invention provides at least one selected from the group represented by the following general formulas (I) to (III).
Mainly composed of repeating structural units of 5 kinds and having a weight average molecular weight of 5
The present invention provides a conjugated diene sulfonated polymer which is from 0 to 5,000,000.

[0007]

[Chemical 4]

Embedded image

[Chemical 6]

(In the formula, R ^{1 to} R ⁶ are a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 20 carbon atoms, or —SO ₃ X, where X is a hydrogen atom, It is an alkali metal atom, an alkaline earth metal atom, an ammonium group or an amino group, and at least one of R ^{1 to} R ⁶ is-
SO ₃ X. )

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The conjugated diene sulfonated polymer of the present invention is obtained by polymerizing a sulfonated compound represented by the following general formula (IV). [In formula, R < ¹ > -R < ⁶ > is the same as said general formula (I)-(III). ]

The sulfonated compound used in the present invention is a compound in which a conjugated diene is introduced with a sulfone group while leaving two double bonds of the diene. In the present invention, examples of the conjugated diene used for the sulfonated compound include 1,3-butadiene, 1,2-butadiene,
1,2-pentadiene, 1,3-pentadiene, 2,3
-Pentadiene, isoprene, 1,2-hexadiene,
1,3-hexadiene, 1,4-hexadiene, 1,5
-Hexadiene, 2,3-hexadiene, 2,4-hexadiene, 2,3-dimethyl-1,3-butadiene, 2
-Ethyl-1,3-butadiene, 1,2-heptadiene, 1,3-heptadiene, 1,4-heptadiene,
1,5-heptadiene, 1,6-heptadiene, 2,3
In addition to heptadiene, 2,5-heptadiene, 3,4-heptadiene, 3,5-heptadiene, 2-phenylbutadiene and the like, various branched dienes can be mentioned. These conjugated dienes can be used alone or in combination of two or more.

In order to produce the sulfonated product of this conjugated diene, for example, the double bond of the conjugated diene can be produced by sulfonation by the method shown below. That is, sulfur trioxide can be used as a sulfonating agent for the conjugated diene to effect sulfonation under known conditions as shown in the Chemical Society of Japan, edited by Experimental Chemistry Course. In this case, as the sulfonating agent, usually, sulfur trioxide alone or a complex of sulfur trioxide and an electron-donating compound is used. Here, examples of the electron-donating compound include ethers such as N, N-dimethylformamide, dioxane, dibutyl ether, tetrahydrofuran and diethyl ether; amines such as pyridine, piperazine, trimethylamine, triethylamine and tributylamine; dimethyl sulfide and diethyl. Examples thereof include sulfides such as sulfides; nitrile compounds such as acetonitrile, ethyl nitrile, and propyl nitrile. Among these, N, N-dimethylformamide and dioxane are preferable.

The amount of the sulfonating agent is usually 0.1 to 10 mol in terms of sulfur trioxide, based on 1 mol of the conjugated diene,
The amount is preferably 0.5 to 3 mol, and if the amount is less than 0.1 mol, the reaction yield is low. On the other hand, if the amount is more than 10 mol, unreacted sulfur trioxide increases, and after neutralization with alkali, a large amount of sodium sulfate is added. It is not preferable because it occurs and the purity decreases. In the case of this sulfonation, it is also possible to use a solvent inert to sulfur trioxide which is a sulfonating agent, and examples of this solvent include halogenated hydrocarbons such as chloroform, dichloroethane, tetrachloroethane, tetrachloroethylene and dichloromethane. Nitro compounds such as nitromethane and nitrobenzene; and aliphatic hydrocarbons such as liquid sulfur dioxide, propane, butane, pentane, hexane and cyclohexane. These solvents can be used as a mixture of two or more kinds as appropriate.

The reaction temperature for this sulfonation is usually -7.
0 to 200 ° C, preferably -30 to 50 ° C, -7
If the temperature is lower than 0 ° C, the sulfonation reaction will be delayed, which is not economical.
On the other hand, if the temperature exceeds 200 ° C., a side reaction may occur and the product may turn black, which is not preferable. Thus, a cyclic intermediate in which sulfur trioxide is cyclically bonded to the conjugated diene (cyclic sulfonate ester of conjugated diene, generic name sultone, hereinafter referred to as “cyclic intermediate”) is produced. The sulfonated compound represented by the general formula (IV) used in the present invention is to convert the cyclic bond into a double bond having a sulfone group bonded thereto by allowing a basic compound to act on the cyclic intermediate. (Hereinafter referred to as “double bond”).

Examples of the basic compound include alkali metal hydroxides such as sodium hydroxide, potassium hydroxide and lithium hydroxide; sodium methoxide, sodium ethoxide, potassium methoxide, sodium t-butoxide and potassium t. -Alkali metal alkoxides such as butoxide; methyl lithium, ethyl lithium, n-butyl lithium, sec-butyl lithium, amyl lithium, propyl sodium, methyl magnesium chloride, ethyl magnesium bromide, propyl magnesium iodide, diethyl magnesium, diethyl zinc, triethyl. Organometallic compounds such as aluminum and triisobutylaluminum; ammonia water, trimethylamine, triethylamine, tripropylamine, tributylamine, Jin, amines such as piperazine;
Mention may be made of metallic compounds such as sodium, lithium, potassium, calcium and zinc. These basic compounds may be used alone or in combination of two or more. Among these basic compounds, alkyl metal hydroxides are preferable, and sodium hydroxide is particularly preferable.

The amount of the basic compound used is usually 0.1 to 3 mol, preferably 0.5 to 1 mol of the conjugated diene.
When the amount is less than 0.1 mol, the double bond formation of the cyclic bond is not promoted and the cyclic compound remains as it is, or a hydroxy olefin represented by the following general formula (V) is produced, A compound having almost no polymerization performance is produced.
In the following general formula (V), R ^{1 to} R ⁶ are the same as the above general formulas (I) to (III). On the other hand, if it exceeds 10 moles, there is a large amount of unreacted alkali, and the purity of the product is reduced, which is not preferable. At the time of double-bonding the cyclic intermediate, the basic compound can be used in the form of an aqueous solution, or can be used by dissolving it in an organic solvent inert to the basic compound.

Examples of the organic solvent include, in addition to the above various organic solvents, directional hydrocarbon compounds such as benzene, toluene and xylene; alcohols such as methanol, ethanol, propanol, isopropanol and ethylene glycol. These solvents may be 2
A mixture of two or more species can be used. When the basic compound is used as an aqueous solution or an organic solvent solution, the concentration of the basic compound is usually 1 to 70% by weight, preferably 10 to 50% by weight.

The reaction temperature for double bond formation is usually-
It is carried out at 30 to 150 ° C., preferably −10 to 70 ° C., more preferably 0 to 50 ° C., and can be carried out under any conditions of normal pressure, reduced pressure or elevated pressure. Furthermore, the reaction time for double bond formation is usually 0.1 to 24 hours, preferably 0.5 to 5 hours. In addition, upon the formation of this double bond, the desired sulfonated compound represented by the general formula (IV) can be obtained also by adding water or alcohol to the cyclic intermediate and then performing a dehydration reaction or dealcoholization reaction.

The cation species of the sulfonated product thus obtained are not particularly limited, but hydrogen, alkali metal, alkaline earth metal, ammonium, amine and the like are preferable in order to make them water-soluble. . Examples of the alkali metal include sodium and potassium, and examples of the amine include alkylamine such as methylamine, ethylamine, propylamine, dimethylamine, diethylamine, triethylamine, butylamine dibutylamine and tributylamine, ethylenediamine, diethylenetriamine and triethylenetetramine. Polyamines,
Examples thereof include morpholine and piperidine, and examples of the alkaline earth metal include calcium and magnesium. These cation species can be exchanged with other cation species by various ion exchange techniques.

The conjugated diene sulfonated polymer of the present invention can be obtained by polymerizing the sulfonated compound represented by the above general formula (IV). In this polymerization, in addition to the sulfonated compound, it is copolymerized therewith. It is also possible to copolymerize other possible monomers (hereinafter referred to as “other monomers”) in an amount of 99% by weight or less, preferably 1 to 98% by weight, more preferably 10 to 90% by weight. As the other copolymerizable monomer, aromatic compounds such as styrene, α-methylstyrene, vinyltoluene and p-methylstyrene;
Acrylic acid or alkyl esters of methacrylic acid such as methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacryl; acrylic acid, methacrylic acid , Crotonic acid, maleic acid, fumaric acid, anhydrides of monocarboxylic or dicarboxylic acids such as itconic acid; butadiene, isoprene, 2-chloro-1,3-
Aliphatic conjugated dienes such as butadiene and 1-chloro-1,3-butadiene; vinyl cyanide compounds such as acrylonitrile and methacrylonitrile; vinyl chloride, vinylidene chloride, vinyl methyl ethyl ketone, vinyl methyl ether, vinyl acetate, vinyl formate, allyl acetate, Methallyl acetate, acrylamide, methacrylamide, N-methylol acrylamide, glycidyl acrylate, glycidyl methacrylate, acrolein, allyl alcohol and the like are used, but preferably from the group of methacrylic acid, acrylic acid, acrylamide and sodium styrene sulfonate. It is at least one selected monomer.

The conjugated diene sulfonated polymer of the present invention contains the sulfonated compound represented by the above general formula (IV) and, if necessary, another monomer copolymerizable therewith, such as water or an organic compound. In the presence of a solvent for polymerization such as a solvent, radical polymerization is performed using a radical polymerization initiator, a chain transfer agent, or the like. Here, examples of the organic solvent for polymerization used for radical polymerization include alcohols such as methanol, ethanol, and isopropanol; xylene, toluene,
Examples thereof include aromatic hydrocarbons such as benzene; and aliphatic hydrocarbons such as butane, pentane, hexane, cyclohexane and heptane. Of these polymerization solvents, water or methanol is preferable. Radical polymerization initiators include persulfate initiators such as potassium persulfate, sodium persulfate and ammonium persulfate; inorganic initiators such as hydrogen peroxide; cumene hydroperoxide, isopropylbenzene hydroperoxide, paramenthan hydro Examples thereof include organic peroxides such as peroxides and benzoyl peroxide; and organic initiators represented by azo initiators such as azobisisobutyronitrile.

The amount of the radical polymerization initiator used is preferably 0.01 based on 100 parts by weight of the total amount of the monomers.
10 to 10 parts by weight, particularly preferably 0.1 to 5 parts by weight. As the chain transfer agent, t-dodecyl mercaptan,
Mercaptans such as octyl mercaptan, n-tetradecyl mercaptan, octyl mercaptan, t-hexyl mercaptan and n-hexyl mercaptan;
Halogen compounds such as carbon tetrachloride and ethylene bromide
Usually 0.001 per 100 parts by weight of total monomer
About 10 to 10 parts by weight is used. In order to accelerate radical polymerization, for example, sodium pyrobisulfite, sodium sulfite, sodium hydrogen sulfite, ferrous sulfate, glucose, formaldehyde sodium sulfoxylate, L-ascorbic acid and its salt, reduction of sodium hydrogen sulfite, etc. Agents; chelating agents such as glycine, alanine, and sodium ethylenediaminetetraacetate can also be used in combination.

In radical polymerization, in addition to the above-mentioned radical initiator, chain transfer agent, etc., various electrolytes, pH adjusters, etc. may be used in combination if necessary, and the total amount of monomers may be 100%.
50 to 1,000 parts by weight of water, or 50 to 1,000 parts by weight of organic solvent, and the radical initiator, chain transfer agent, etc., in an amount within the above range, to obtain a polymerization temperature of -50. The radical polymerization is carried out under the polymerization conditions of ˜200 ° C., preferably 0˜150 ° C., particularly preferably 5˜80 ° C. and a polymerization time of 0.1˜40 hours. The method of adding the monomer containing the sulfonate as a main component is not particularly limited, and any method such as a batch addition method, a continuous addition method or a divided addition method may be employed. The final polymerization conversion rate of the obtained sulfonated polymer is 10% or more, especially 3%.
It is preferably 0% or more. Further, the polymerization method of the present invention is not limited to the radical polymerization described above,
The target sulfonated polymer can also be obtained by conventionally known anionic polymerization.

The sulfonated polymer thus obtained has a repeating structural unit represented by the following general formula (I), general formula (II) and / or general formula (III).

[0024]

[Chemical 7]

Embedded image

[Chemical 9]

[In the general formulas (I) to (III), R ¹ to
R ⁶ is the same as above. The sodium sulfonate-converted weight average molecular weight of the sulfonated polymer thus obtained cannot be uniquely determined depending on the intended use,
Usually 500 to 5,000,000, preferably 1,0
It is from 00 to 500,000.

The conjugated diene sulfonated polymer of the present invention can be mutually exchanged with an acid type or a salt of an alkali metal, an alkaline earth metal, ammonium, an amine by an ion exchange method or a neutralization reaction. Further, the conjugated diene sulfonated polymer of the present invention is neutralized in an alkaline aqueous solution such as sodium hydroxide, potassium hydroxide or aqueous ammonia, when a salt is not formed in the sulfonated compound prior to polymerization. Thus, a salt of a water-soluble or hydrophilic polymer in which at least a part of sulfone groups forms a salt is obtained. Here, the cation species for forming a salt on the sulfone group of the sulfonated polymer, that is, the cation species of the sulfonate is not particularly limited, but in order to make it water-soluble, the aforementioned hydrogen atom, alkali Metals, alkaline earth metals, ammonium, amines and the like are preferred. These cation species can be exchanged with other cation species by various ion exchange techniques.

Thus, an aqueous solution of a water-soluble (co) polymer salt is prepared. In the present invention, a solid water-soluble (co) polymer salt is separated from the aqueous solution by drying if necessary. Can be obtained. The degree of neutralization of the sulfone groups may be appropriately selected within a range where the (co) polymer salt becomes water-soluble or water-dispersible, and the sulfone groups may form different salts. .

The structure of the sulfonated compound used in the present invention or the conjugated diene sulfonated polymer of the present invention obtained therefrom can be confirmed from the absorption of the sulfonic group by infrared absorption spectrum. It can be known by titration with acid or alkali. The structure can be confirmed by the presence of an alkyl group or olefinic hydrogen by nuclear magnetic resonance spectrum.

The conjugated diene sulfonated polymer of the present invention is a dispersant such as a cement dispersant, a concrete dispersant, a calcium carbonate dispersant, a coal dispersant, a gypsum dispersant, a pigment dispersant and a petroleum / coal mixture dispersant; Scale inhibitors such as calcium carbonate, calcium phosphate and silica, water treatment agents such as anticorrosion agents; water absorbing gels; reactive emulsifiers,
It can be used as a fiber dyeing agent. Further, the conjugated diene sulfonated polymer of the present invention is a homopolymer or a copolymer with another monomer to increase hydrophilicity, antistatic property of rubber, improvement of coloring property of fiber, etc. It can be used for many purposes.

[0030]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to the following examples. In the examples,% and parts are based on weight unless otherwise specified. Example 1 A four-necked flask having an internal volume of 1 liter was replaced with nitrogen, 400 ml of methylene chloride that had been dehydrated and deoxygenated in advance was added, and then 31 ml of dioxane that had been dehydrated and deoxygenated was added and stirred. While cooling to 5-10 ° C. Next, 15 ml of sulfur trioxide (28.8 g = 0.3
6 mol) was added dropwise to form a complex of sulfur trioxide and dioxane. Furthermore, it was made to react for 15 minutes. Isoprene (2-methyl-1,3-butadiene) 24.
Methylene chloride solution in which 5 g (0.36 mol) was dissolved 15
0 ml was added dropwise over 1 hour, and after the addition was completed, another 30
Stirring was continued for a minute.

Next, 100 ml of an aqueous solution in which 14.4 g of sodium hydroxide was dissolved was added, the internal pressure of the flask was reduced, and the mixture was gradually heated in a water bath to distill and remove the solvent and dioxane, and then to dryness. This gave 50.2 g of the product (crude sodium 2-methyl-1,3-butadiene-1-sulfonate). 30 of this product
After dissolving in 0 cc of water, 200 cc of toluene was added and shaken vigorously to extract a toluene-soluble component, and the aqueous solution was dried to dryness.

Next, 2 g of sodium 2-methyl-1,3-butadiene-1-sulfonate (hereinafter referred to as "MBSN") thus obtained was placed in a 30 ml pressure resistant bottle and subjected to nitrogen substitution. , Sodium persulfate 0.06
g was added and polymerization was carried out for 2 hours in a rotary polymerization tank at 70 ° C.
The polymerization conversion rate of the polymer was 65%, and as a result of gel permeation chromatography (GPC) analysis, the weight average molecular weight in terms of sodium polystyrene sulfonate (hereinafter referred to as “weight average molecular weight”) was 20,000, and The acid group was determined by titration to be 5.5 meq / g. The nuclear magnetic resonance spectrum ( ¹ H-NMR) of the obtained polymer is shown in FIG. 1, and the infrared absorption spectrum is shown in FIG. 1 and 2, the polymer of this example is
It was found that the following repeating structural units were the main components. (In the formula, m and n represent the number of repeating structural units corresponding to the weight average molecular weight, and by the nuclear magnetic resonance spectrum, m:
The ratio of n was found to be about 54:46. )

Example 2 The copolymerization of MBSN synthesized in Example 1 and methacrylic acid was carried out. That is, 13 g (0.076 mol) of MBSN and 6.5 g (0.076 mol) of methacrylic acid were placed in a 100 ml pressure bottle, 58.5 g of water and 0.20 g of potassium persulfate were added, and then the stopper was placed. Then 70
Polymerization was carried out at ℃ for 5 hours. Polymerization conversion is 74%
And the weight average molecular weight was 28,500. The obtained polymer was dialyzed with a cellulose tube to remove low molecular weight components, and then the nuclear magnetic resonance spectrum ( ¹ H-NM
R, FIG. 3) and infrared absorption spectrum (FIG. 4) were measured. When the copolymerization composition ratio of the two was determined from the nuclear magnetic resonance spectrum of FIG. 3, MBSN / methacrylic acid (molar ratio) = 29/71.

Examples 3 to 5 Acrylic acid, acrylamide and sodium styrenesulfonate were used instead of methacrylic acid in Example 2 and copolymerization was carried out in the same manner as in Example 2. The results are shown in Table 1
It is shown in FIG.

Obvious from Examples 2-5 and FIGS. 3-10
Thus, the nuclear magnetic resonance spectrum ( ¹H-NMR) and
And infrared absorption spectrum, sulfonate (MBS
Absorption of a polymer of N) and another monomer is observed. Well
In addition, the MBSN homopolymer of Example 1 and the polystyrene of Example 5 were used.
GPC chart of sodium sulfonate copolymer
It shows in FIG. As is clear from FIG. 11, the MBSN
The homopolymer is detected by infrared absorption spectrum (RI) detector.
UV absorption spectrum (UV, wavelength
It can be seen that it is not detected by the detector of 254 nm).
On the other hand, MBSN of Example 5 and sodium styrenesulfonate
Copolymer with um was detected by RI and UV
Are doing This means that if it is a mixture of homopolymers
MBSN homopolymer was detected in the UV detector
No, only the homopolymer of sodium styrene sulfonate
Since it is detected, RI and UV have completely different shapes.
Thus, according to the GPC chart of Example 5 of the present invention,
In addition, the ones detected by RI and UV have similar shapes.
The fact that it is a copolymer indicates that it is a copolymer.
It

Comparative Example 1 Polymerization was carried out in the same manner as in Example 1 using sodium vinyl sulfonate which was a commercially available reagent. Polymerization conversion is 3
2%, the weight average molecular weight of the polymer was about 1,000.

Comparative Example 2 Polymerization was carried out in the same manner as in Example 1 using sodium allyl sulfonate which was a commercially available reagent. Polymerization conversion is 4
7%, the weight average molecular weight of the polymer was about 400. As is clear from the comparison between Example 1 and Comparative Examples 1 and 2, the monomer (sulfonated product) used in the present invention is characterized by a high polymerization conversion rate and a high molecular weight of the obtained polymer. It can be seen that it is superior as an industrial raw material in comparison with conventionally known sodium vinyl sulfonate, sodium allyl sulfonate and the like.

[0038]

[Table 1]

[0039]

[Table 2]

Example 6 Instead of 400 ml of methylene chloride used in Example 1, 400 ml of dioxane was used and reacted with sulfur trioxide at 20 ° C. to form a complex. Next, 150 ml of a dioxane solution in which 24.5 g (0.36 mol) of isoprene was dissolved was added dropwise to this solution over 1 hour. After completion of dropping, stirring was continued for another 30 minutes. Then, a hexane solution of n-butyllithium having a concentration of 1.6 mol / l was added dropwise over 30 minutes, and further reacted at 30 ° C. for 12 hours. After completion of the reaction, 300 ml of methanol was added, the solvent was removed, and the mixture was dried to give 45.1 g of a product (lithium 2-methyl-1,3-butadiene-1-sulfonate). When this product was polymerized in the same manner as in Example 1, the polymerization conversion rate was 9.8%, and the GPC analysis revealed that the weight average molecular weight was 9,000.

Example 7 The concentration of sodium hydroxide in Example 1 was changed to a 50% aqueous solution. After adding a sodium hydroxide aqueous solution, the mixture was stirred at 40 ° C. for 5 hours. The formed precipitate was filtered and the precipitate was dried under vacuum to obtain 62.5 g of colorless powder. The nuclear magnetic resonance spectra ( ¹ H-NMR and ¹³ C-NMR) of this sulfonate are shown in FIGS. 12 to 13, the infrared absorption spectrum is shown in FIG. 14, and the DSC chart is shown in FIG. Polymerization was performed using this sulfonated compound in the same manner as in Example 1. As a result, a polymer having a polymerization conversion rate of 71% and a weight average molecular weight of 41,000 was obtained.

Example 8 As in Example 7, after adding an aqueous sodium hydroxide solution to the reactor, the apparatus shown in FIG. 16 was attached, and water present in the reaction system was azeotroped with methylene chloride and cooled. After that, when the operation of returning only methylene chloride to the reaction system was repeated for 24 hours, the amount of water taken out from the reaction system became constant. The formed precipitate was vacuum dried to obtain 65.7 g of a colorless powder. Polymerization was carried out in the same manner as in Example 1 to obtain a polymerization conversion rate of 75% and a weight average molecular weight of 40,00.
0 polymer was obtained.

Comparative Example 3 Instead of the aqueous sodium hydroxide solution of Example 1, 500 ml of distilled water was added, and the mixture was stirred at 40 ° C. for 5 hours.
The pressure was reduced to 600 mmHg and heating was performed to remove all organic solvents, and the solution was concentrated to a total amount of 200 g of aqueous solution.
The solid content in this aqueous solution was 22.6%. To this solution, potassium persulfate corresponding to 3 parts was added to 100 parts of solid content, and polymerization was carried out in the same manner as in Example 1, but no polymer was obtained at all. Izuvest. Akad. Na
uk. SSSR, Ser, Khim. 1327 (197
As described in 9), water alone produces 2-methyl-
4-hydroxy-2-butene-1-sulfonic acid is produced,
It is presumed that the intended sulfonated diene cannot be obtained.

[0044]

INDUSTRIAL APPLICABILITY The conjugated diene sulfonated polymer of the present invention has a sulfonyl group exhibiting strong acidity, has a large ion exchange capacity, and can easily produce a high molecular weight polymer. Therefore, the conjugated diene sulfonated polymer of the present invention is useful as various dispersants, emulsifiers, water treatment agents and the like.

[Brief description of drawings]

FIG. 1 is a nuclear magnetic resonance spectrum of a sulfonated polymer (
¹ H-NMR).

FIG. 2 is an infrared absorption spectrum of a sulfonated polymer.

FIG. 3 is a nuclear magnetic resonance spectrum ( ¹ H-NMR) of a sulfonated copolymer.

FIG. 4 is an infrared absorption spectrum of a sulfonated copolymer.

FIG. 5 is a nuclear magnetic resonance spectrum ( ¹ H-NMR) of a sulfonated copolymer.

FIG. 6 is an infrared absorption spectrum of a sulfonated copolymer.

FIG. 7 is a nuclear magnetic resonance spectrum ( ¹ H-NMR) of a sulfonated copolymer.

FIG. 8 is an infrared absorption spectrum of a sulfonated copolymer.

FIG. 9 is a nuclear magnetic resonance spectrum ( ¹ H-NMR) of a sulfonated copolymer.

FIG. 10 is an infrared absorption spectrum of a sulfonated copolymer.

FIG. 11 is a GPC chart of a sulfonated (co) polymer.

FIG. 12 is a nuclear magnetic resonance spectrum ( ¹ H-NMR) of a sulfonated product of a conjugated diene.

FIG. 13 is a nuclear magnetic resonance spectrum ( ¹³ C-NMR) of a sulfonated product of a conjugated diene.

FIG. 14 is an infrared absorption spectrum of a sulfonated product of a conjugated diene.

FIG. 15 is a DSC chart of a sulfonated product of a conjugated diene.

FIG. 16 is a schematic view of a reaction apparatus used in the present invention.

 ─────────────────────────────────────────────────── --Continued front page (72) Inventor Katsuhiro Ishikawa 2-11-24 Tsukiji, Chuo-ku, Tokyo Japan Synthetic Rubber Co., Ltd.

Claims (1)

[Claims] 1. A conjugated diene mainly composed of at least one repeating structural unit selected from the group represented by the following general formulas (I) to (III) and having a weight average molecular weight of 500 to 5,000,000. Sulfonated polymer. Embedded image Embedded image Embedded image (In the formula, R ^{1 to} R ⁶ are a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 20 carbon atoms, or —SO ₃
X is a hydrogen atom, an alkali metal atom, an alkaline earth metal atom, an ammonium group or an amino group, and at least one of R ^{1 to} R ⁶ is —SO ₃ X. )