JP2001200009A - Preparation method of water-soluble polymer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a preparation method of a water-soluble polymer which has a little residue of an unreacted monomer in a course of the preparation of the polymer. SOLUTION: In the preparation method of the water-soluble polymer comprising polymerizing or copolymerzing at least one water-soluble monomer as a constituent monomer, the method is characterized by selecting a substance which generates a water-soluble acidic material as a polymerization initiator, using water or a water solution of a water-miscible solvent as the solvent and polymerizing the monomer in the presence of a salt.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for producing a water-soluble polymer, which does not require a step of removing residual monomers.

[0002]

2. Description of the Related Art In the production of polymers having a polymerization reaction of a monomer as an essential component, the most problematic problem is the residual unreacted monomer and its removal. This is because the reactivity of the monomer itself is maintained and the molecular weight is low, which may cause a safety problem when absorbed into the body. The removal of such a monomer can be solved without much trouble by removing the water-insoluble polymer by distilling it off with steam or washing it with a solvent. As for the polymer, the monomer itself is also water-soluble, and there is no solvent that dissolves the monomer and does not dissolve the polymer.Thus, solvent washing cannot be performed. Since the apparent molecular weight increases because of the addition, great difficulty is involved, and such a water-soluble polymer can be purified by means such as ultrafiltration or gel filtration with an aqueous solution, post-reaction polymerization at high temperatures, etc. There was no other choice but to use such production means and purification means. Under such circumstances, there has been a demand for a method for preventing unreacted monomers from remaining in the process of producing the water-soluble polymer.

On the other hand, in a method for producing a water-soluble polymer,
1) In a method for producing a water-soluble polymer by polymerizing or copolymerizing at least one or more of water-soluble monomers as constituent monomers, 2) A substance which is ionic or decomposed into a polymerization initiator to generate ions And 3) using water or a water-miscible solvent as a solvent as an aqueous solution, and 4) performing polymerization using a solvent as a buffer system.

[0004]

SUMMARY OF THE INVENTION The present invention has been made under such circumstances, and it is an object of the present invention to provide means for preventing unreacted monomers from remaining in the process of producing a water-soluble polymer. And

[0005]

In view of such circumstances, the present inventors have made intensive research efforts to find a means for preventing unreacted monomers from remaining in the process of producing a water-soluble polymer. The polymerization initiator is ionic or selected from a substance that decomposes to generate ions, and the solvent is water or an aqueous solution of a water-miscible solvent, and the polymerization is performed by using the solvent as a buffer system. The inventors have found that there is almost no unreacted monomer, and have completed the invention. That is, the present invention
1) In a method for producing a water-soluble polymer by polymerizing or copolymerizing at least one or more of water-soluble monomers as constituent monomers, 2) A substance which is ionic or decomposed into a polymerization initiator to generate ions And 3) using a solvent as an aqueous solution of water or a water-miscible solvent, and 4) carrying out polymerization using a solvent as a buffer system to provide a method for producing a water-soluble polymer.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention relates to a method for producing a water-soluble polymer, which comprises: 1) polymerizing or copolymerizing at least one or more water-soluble monomers as constituent monomers to produce a water-soluble polymer. 2) selecting a substance that is ionic or decomposes to produce an ion as a polymerization initiator;
It is an object of the present invention to provide a production method characterized in that a solvent is water or an aqueous solution of a water-miscible solvent, and 4) polymerization is carried out using a solvent as a buffer system. Here, the water-soluble polymer of the present invention is obtained by polymerizing a monomer.
It means a polymer substance having a molecular weight of 000 or more and having a property such that when a 1000-fold amount of water is added and stirred, a transparent and uniform solution is obtained. Such a water-soluble polymer is
A polymer or copolymer containing one or more selected from water-soluble monomers as constituent monomers,
Such water-soluble monomers include, for example, acrylic acid, methacrylic acid, esters with alkylene diols,
Polyoxyalkylene adducts, phospholipid derivatives and water-soluble derivatives of acrylic acid and methacrylic acid such as esters with sugars and vinylpyrrolidone, more specifically, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, Hydroxypropyl methacrylate, hydroxypropyl acrylate, 4-hydroxybutyl methacrylate, 4-hydroxybutyl acrylate, polyethylene glycol monoacrylate,
Preferable examples include polyethylene glycol monomethacrylate, alkoxy polyethylene glycol acrylate, alkoxy polyethylene glycol methacrylate, phenoxy polyethylene glycol acrylate, phenoxy polyethylene glycol methacrylate, 2-glucosiloxyethyl methacrylate, and 2-methacryloxyethyl phosphorylcholine. These water-soluble constituent monomers are preferably contained in the water-soluble polymer in an amount of 30% by weight or more, more preferably 50% by weight or more. This is because if the amount is too small, the water solubility is impaired.

The water-soluble polymer to be subjected to the production method of the present invention may contain, as a constituent monomer, one or two or more monomers selected from non-water-soluble monomers as long as the water solubility is not impaired. it can. Such non-water-soluble constituent monomers include methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, amyl methacrylate, and n-hexyl methacrylate. , Cyclohexyl methacrylate,
N-octyl methacrylate, methacryl 2-ethylhexyl, dodecyl methacrylate, cetyl methacrylate, stearyl methacrylate, benzyl methacrylate, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, tert-acrylate -Butyl, amyl acrylate, n-hexyl acrylate,
Cyclohexyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate,
Cetyl acrylate, stearyl acrylate, benzyl acrylate, styrene, α-methylstyrene, 2,2,2-
Trifluoroethyl methacrylate, 2,2,2-trifluoroethyl acrylate, 2,2,3,3-tetrafluoropropyl methacrylate, 2,2,3,3-tetrafluoropropyl acrylate, 1,1,1,3, 3,3-hexafluoroisopropyl methacrylate, 1,1,1,3,3,3
-Hexafluoroisopropyl acrylate, 1H, 1
H, 5H-octafluoro-n-pentyl methacrylate, 1H, 1H, 5H-octafluoro-n-pentyl acrylate, 1H, 1H, 2H, 2H-heptadecafluoro-n-decyl methacrylate and 1H, 1H, 2H, 2H −
Heptadecafluoro-n-decyl acrylate and the like can be specifically preferably exemplified. The preferred content of these non-water-soluble constituent monomers in the water-soluble polymer of the present invention is 70% by weight or less, more preferably 50% by weight or less.
% By weight or less. This is because if it is too large, water solubility is impaired.

[0008] The water-soluble polymer of the present invention comprises one or more selected from the above water-soluble monomers, and optionally one or two or more selected from the above non-water-soluble monomers. Is characterized by using water or a one-phase solution of water and a solvent miscible with water together with a polymerization initiator that produces an ionic substance after the reaction as a solvent, and polymerizing or copolymerizing with such a solvent as a buffer system. A polymerization initiator which forms an ionic substance after an ionic or reactive reaction is a commonly known polymerization initiator and a catalyst which forms an ionic substance after acting as a catalyst for ionic or radical polymerization. In the case of a persulfate, ammonium, potassium, and sodium salts of persulfate can be preferably exemplified. Examples of the redox initiator include hydrogen peroxide, ferrous salt, and persulfate.
Examples thereof include sodium acid sulfite. These catalysts may be added in a very small amount, specifically 0.05 to 3.0% by weight, based on the total amount of the monomers. These polymerization initiators can be used alone or in combination of two or more. The water-miscible solvent used as the solvent only needs to have a degree of solubility that is miscible with water in the form of use. Specific examples include alcohols such as methanol, ethanol, and isopropyl alcohol, and acetone. And ketones such as methyl ethyl ketone, cellosolves such as methyl cellosolve and ethyl cellosolve, tetrahydrofuran, dimethyl sulfoxide and dimethylformamide. These can be used alone or in combination of two or more. In the production method of the present invention, these solvents are mixed with water and used in the form of a one-phase solution. In such a form, the ratio of water to the solvent is 1: 4 to 4: It is preferable to set the range to about 1. This is because if the amount of the solvent is too large, salts exhibiting a buffering effect described below may be precipitated and the effect may be impaired.If the amount of the solvent is too small, only a solvent effect equivalent to that of water to which no solvent is added is obtained, and the solvent is added. Is meaningless. The amount of these solvents used in the production method of the present invention is preferably 1 to 100 times the total amount of the monomers. The method for producing a water-soluble polymer of the present invention is characterized in that a polymerization reaction is carried out using a solvent as a buffer system. As a means for using the solvent as a buffer system, for example, an aqueous solution of a salt having a buffering action or a mixed solvent of this aqueous solution and a water-miscible solvent may be used. Examples of such a salt include phosphoric acid Diammonium hydrogen phosphate, ammonium dihydrogen phosphate, disodium hydrogen phosphate, sodium dihydrogen phosphate, dipotassium hydrogen phosphate,
Potassium dihydrogen phosphate, sodium hydrogen sulfate, ammonium hydrogen sulfate, potassium hydrogen sulfate, ammonium hydrogen carbonate, potassium hydrogen carbonate, sodium hydrogen carbonate, diammonium hydrogen citrate, dipotassium hydrogen citrate, disodium hydrogen citrate, citric acid Diammonium hydrogen, dipotassium hydrogen citrate, disodium hydrogen citrate, ammonium hydrogen tartrate, potassium hydrogen tartrate, sodium hydrogen tartrate, sodium tetraborate, ammonium hydrogen phthalate, potassium hydrogen phthalate, sodium hydrogen phthalate, succinic acid Examples thereof include ammonium hydrogen, potassium hydrogen succinate, and sodium hydrogen succinate. Such a salt may be added to a final concentration of about 0.1 mM to 1 M. It is also possible to prepare a buffer solution in advance and use it alone or as a mixed solvent with a water-miscible solvent.
As such a buffer system, for example, potassium chloride-
Hydrochloric acid solution (pH 1.0 to 2.2; 20 ° C), potassium hydrogen phthalate-hydrochloric acid solution (pH 2.2 to 3.8; 20 ° C), potassium hydrogen phthalate-sodium hydroxide solution (pH 4.0)
-6.2; 20 ° C), potassium dihydrogen phosphate-sodium hydroxide solution (pH 5.8-8.0; 20 ° C), boric acid
Potassium chloride-sodium hydroxide solution (pH 7.8-1
0.0; 20 ° C), glycine / sodium chloride-hydrochloric acid solution (pH 1.15 to 4.68; 18 ° C), glycine / sodium chloride-sodium hydroxide solution (pH 8.53 to 1)
2.90; 20 ° C), sodium citrate-hydrochloric acid solution (pH 1.17 to 4.96; 18 ° C), sodium citrate-sodium hydroxide solution (pH 4.96 to 6.69; 2)
0 ° C.), borax-hydrochloric acid solution (pH 7.61 to 9.23;
20 ° C.), borax-sodium hydroxide solution (pH 9.2)
3 to 12.32; 20 ° C), potassium dihydrogen phosphate-disodium hydrogen phosphate solution (pH 5.20 to 8.30; 1)
8 ° C.), potassium hydrogen citrate-citric acid solution (pH 2.
2 to 3.6; 18 ° C), potassium hydrogen citrate-hydrochloric acid solution (pH 2.2 to 3.6; 18 ° C), potassium hydrogen citrate-sodium hydroxide solution (pH 3.8 to 6.0; 18)
C), succinic acid-borax solution (pH 3.0-5.8; 18)
C), potassium hydrogen citrate-borax solution (pH 3.8-
6.0; 18 ° C), potassium dihydrogen phosphate-borax solution (pH 5.8 to 9.2; 18 ° C), borax-sodium carbonate solution (pH 9.2 to 11.0; 18 ° C), hydrochloric acid Sodium carbonate solution (pH 10.17 to 11.24; 18 ° C),
Disodium hydrogen phosphate-sodium hydroxide solution (pH 1
1.0-12.0; 18 ° C), tartaric acid-sodium tartrate solution (pH 1.4-4.5; room temperature), lactic acid-sodium lactate solution (pH 2.3-5.3; room temperature), acetic acid-sodium acetate Solution (pH 3.19 to 6.22; room temperature), ammonium chloride-ammonium hydroxide solution (pH 8.0 to 11.1).
0; room temperature), sodium diethyl barbiturate / sodium acetate-hydrochloric acid solution (pH 2.62 to 9.64; 25)
C), sodium diethylbarbiturate-hydrochloric acid solution (pH 6.40 to 9.80; 25 ° C), sodium dimethylglycine-hydrochloric acid solution (pH 8.60 to 10.58; 30).
° C), boric acid / potassium chloride-sodium carbonate solution (pH
7.44 to 11.0; 16 ° C), boric acid / sodium chloride-borax solution (pH 6.77 to 9.11; 18 ° C), disodium hydrogen phosphate-citric acid solution (pH 2.2 to 8.0).
0; room temperature), sodium carbonate-sodium bicarbonate solution (pH 8.94-10.77; 18 ° C), sodium acetate-hydrochloric acid solution (pH 0.65-5.20; room temperature), acetic acid-
Sodium acetate solution (pH 3.6 to 5.6; 18 ° C), phosphoric acid / boric acid / glacial acetic acid-sodium hydroxide solution (pH 1.
81-11.98; 18 ° C), citric acid / potassium dihydrogen phosphate / boric acid / diethyl barbituric acid / hydrochloric acid / sodium hydroxide solution (pH 2.40-12.02; room temperature), 2,4,6 Trimethylpyridine-hydrochloric acid solution (pH
6.45 to 8.35; 23 ° C), trisoxymethylaminomethane-hydrochloric acid solution (pH 7.20 to 9.10; 23)
C), 2-aminomethyl-1,3-propanediol-hydrochloric acid solution (pH 7.83 to 9.72; 23C), potassium dihydrogen phosphate-sodium hydrogen carbonate solution (pH 6.06 to
7.59; room temperature). Such a buffer may be used as it is, or may be used after being diluted and concentrated so as not to impair the buffering action. In this case, the final concentration of the salts in the solution may be about 0.1 mM to 1 M. Furthermore, it is also possible to prepare a solution of salts, acids or bases that forms a buffer system with the ions of the initiator, and use it alone or as a mixed solvent with a water-miscible solvent. For example, when ammonium persulfate is used, for example, acids such as hydrochloric acid, sulfuric acid, acetic acid, and phosphoric acid, or sodium chloride, potassium chloride, ammonium chloride, and sodium sulfate are used at a concentration that forms a buffer system with ammonium ions. An aqueous solution of salts such as potassium sulfate, ammonium sulfate, sodium carbonate, potassium carbonate, ammonium carbonate, sodium acetate, potassium acetate, and ammonium acetate may be prepared and used alone or as a mixed solvent with a water-miscible solvent. When sodium persulfate is used, acids such as hydrochloric acid, phosphoric acid, acetic acid, citric acid, tartaric acid, lactic acid, succinic acid, phthalic acid, boric acid, and diethyl barbituric acid are used at a concentration that forms a buffer system with sodium ions. , Borax, salts such as sodium citrate, potassium hydrogen phosphate and phosphoric acid, to prepare an aqueous solution containing both acids and salts such as borax and citric acid, alone or as a mixed solvent with a water-miscible solvent Just use it. Furthermore, when potassium persulfate is used, acids such as hydrochloric acid, phosphoric acid, acetic acid, citric acid, tartaric acid, lactic acid, succinic acid, phthalic acid, boric acid, and the like, sodium hydrogen phosphate and the like are used at a concentration that forms a buffer system with potassium ions. An aqueous solution containing both acids and salts such as phosphoric acid, boric acid, hydrochloric acid and sodium carbonate, borax and citric acid, and both an acid and base such as citric acid and sodium hydroxide, phosphoric acid and sodium hydroxide An aqueous solution may be prepared and used alone or as a mixed solvent with a water-miscible solvent. The above components are charged in one batch, and the temperature is 50 to 80 ° C, more preferably 60 to 75 ° C.
The mixture is heated to about ° C, stirred for 2 to 25 hours as needed, and polymerized to produce a water-soluble polymer with almost no unreacted monomer. Here, it should be noted that according to the present invention, a water-soluble polymer can be produced by a polymerization reaction at a low temperature. As a result, energy can be saved and the direction of the polymerization reaction can be controlled.

[0009]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but it goes without saying that the present invention is not limited to only these Examples.

<Example 1> In a flask equipped with a stirrer, a condenser and a nitrogen inlet tube, methoxypolyethylene glycol (2
3) Methacrylate (Shinnakamura Chemical NK Ester M-230)
G) 24.3 g, 2-hydroxyethyl methacrylate 18.0 g, methyl methacrylate 12.0 g, 1H,
5.7 g of 1H, 2H, 2H heptadecafluoro n-decyl acrylate (Osaka Organic Chemical Biscoat 17F) was dissolved in a mixed solvent consisting of 180 ml of isopropyl alcohol and 120 ml of a commercially available pH 6.86 standard buffer (manufactured by Nacalai Tesque). 1.0 g of ammonium persulfate was added to water 1
A solution dissolved in 0 ml was added and mixed with stirring. While continuing stirring, the atmosphere was sufficiently purged with nitrogen, and then heated to 65 ° C.
The polymerization reaction was performed for an hour. After the reaction was completed, the solution was analyzed by HPLC.
It was 0 ppm or less.

<Example 2> In a flask equipped with a stirrer, a condenser and a nitrogen inlet tube, methoxypolyethylene glycol (9) methacrylate (Shin-Nakamura Chemical NK ester M-90)
G) 37.5 g, 1H, 1H, 5H octafluoro-n-pentyl methacrylate (Osaka Organic Chemical Biscoat 8F
M) 12.5 g of ethyl alcohol 160 ml, 0.2
M potassium chloride aqueous solution 20ml, 0.2N hydrochloric acid 4.2m
1 and 55.8 ml of water. A solution in which 0.5 g of ammonium persulfate was dissolved in 10 ml of water was added thereto, followed by stirring and mixing. While continuing stirring, the atmosphere was sufficiently purged with nitrogen, heated to 80 ° C., and the polymerization reaction was carried out for 4 hours. Then, the temperature was lowered to 55 ° C., and 0.5% of ammonium persulfate was added.
g was dissolved in 10 ml of water, and a polymerization reaction was further performed for 4 hours. After the reaction was completed, the solution was analyzed by HPLC. The residual amount of each monomer was 50 ppm based on the polymer.
It was below.

Example 3 2-Ethylhexyl acrylate 1 in a flask equipped with a stirrer, condenser and nitrogen inlet tube
2.0 g, 16.0 g of acrylic acid, and 12.0 g of n-butyl acrylate in 100 ml of methyl ethyl ketone, 0.2
M was dissolved in a mixed solvent consisting of 20 ml of an aqueous solution of potassium hydrogen phthalate, 1.6 ml of a 2N aqueous solution of sodium hydroxide, and 58.4 ml of water. 0.5g of ammonium persulfate
Was dissolved in 10 ml of water and mixed with stirring. While the stirring was continued, the atmosphere was sufficiently replaced with nitrogen, and then heated to 70 ° C. to carry out a polymerization reaction for 18 hours. After the reaction is completed, the solution is
When analyzed by C, the residual amount of each monomer was 50 ppm or less based on the polymer.

Example 4 In a flask equipped with a stirrer, a condenser and a nitrogen inlet tube, methoxypolyethylene glycol (2
3) Methacrylate (Shinnakamura Chemical NK Ester M-230)
G) 30.0 g, 30.0 g of methyl methacrylate, 180 ml of methyl cellosolve, 12 ml of a 0.05 M aqueous sodium carbonate solution, 10 ml of a 0.1 M sodium hydrogen carbonate solution
It was dissolved in a mixed solvent consisting of 8 ml. A solution prepared by dissolving 0.8 g of potassium persulfate in 10 ml of water was added thereto, followed by stirring and mixing. While the stirring was continued, the atmosphere was sufficiently purged with nitrogen and then heated to 70 ° C. to carry out a polymerization reaction for 14 hours. After the completion of the reaction, the solution was analyzed by HPLC, and the residual amount of each monomer was 50 ppm or less based on the polymer.

Example 5 48.0 g of 2-glucosyloxyethyl methacrylate and 12.0 g of methyl methacrylate were placed in a flask equipped with a stirrer, a condenser and a nitrogen inlet tube, and 180 ml of ethyl alcohol and 120 m of 0.002N hydrochloric acid were added.
l of the mixed solvent. A solution prepared by dissolving 1.0 g of potassium persulfate in 10 ml of water was added thereto, followed by stirring and mixing (forming a potassium chloride-hydrochloric acid-like buffer system). While continuing the stirring, the atmosphere was sufficiently purged with nitrogen, and then heated to 55 ° C. for 20 minutes.
The polymerization reaction was performed for an hour. After the reaction was completed, the solution was analyzed by HPLC.
It was 0 ppm or less.

Example 6 In a flask equipped with a stirrer, a condenser and a nitrogen inlet tube, 28.0 g of 2-methacryloxyethylphosphorylcholine and 12.0 g of ethyl acrylate were composed of 120 ml of methyl alcohol and 80 ml of 0.02M sodium sulfate. It dissolved in the mixed solvent. A solution prepared by dissolving 0.67 g of ammonium persulfate in 10 ml of water was added thereto, followed by stirring and mixing (formation of an ammonium sulfate-ammonium hydroxide-like buffer system). While the stirring was continued, the atmosphere was sufficiently replaced with nitrogen, followed by heating to 60 ° C. to carry out a polymerization reaction for 16 hours. After the completion of the reaction, the solution was analyzed by HPLC, and the residual amount of each monomer was 50 ppm or less based on the polymer.

Example 7 In a flask equipped with a stirrer, a condenser and a nitrogen inlet tube, methoxypolyethylene glycol (2
3) Methacrylate (Shinnakamura Chemical NK Ester M-230)
G) 60.0 g of 1 ml of 0.24N hydrochloric acid in 300 m of water
Dissolved in aqueous solution diluted to l. A solution prepared by dissolving 1.0 g of ammonium persulfate in 10 ml of water was added thereto, followed by stirring and mixing (an ammonium chloride-ammonium hydroxide-like buffer system was formed). While the stirring was continued, the atmosphere was sufficiently replaced with nitrogen, followed by heating to 60 ° C. to carry out a polymerization reaction for 16 hours. After the reaction was completed, the solution was analyzed by HPLC, and the residual amount of the monomer was 50 ppm or less based on the polymer.

Example 8 20.0 g of methacrylic acid, 12.0 g of methyl methacrylate, 1,1,1,3,3,3-hexafluoroisopropyl methacrylate (Osaka 8.0 g of organic chemical bis-coat 6FM) in 150 ml of ethyl alcohol
1, 75 ml of 0.07M phosphoric acid and 75 ml of 0.07M disodium hydrogen phosphate. A solution prepared by dissolving 0.7 g of potassium persulfate in 10 ml of water was added thereto, followed by stirring and mixing (formation of a potassium dihydrogen phosphate-disodium hydrogen phosphate-like buffer system). While the stirring was continued, the atmosphere was sufficiently replaced with nitrogen, and then heated to 70 ° C. to carry out a polymerization reaction for 18 hours. After the reaction was completed, the solution was analyzed by HPLC.
pm or less.

Example 9 Methoxypolyethylene glycol (9) methacrylate (Shin-Nakamura Chemical NK Ester M-90) was placed in a flask equipped with a stirrer, condenser and nitrogen inlet tube.
G) 35.0 g, 15.0 g of 2-hydroxyethyl methacrylate, and 5.0 g of styrene were added to tetrahydrofuran 1
It was dissolved in a mixed solvent consisting of 20 ml and 180 ml of a commercially available pH 4.01 standard buffer (manufactured by Nacalai Tesque). A solution in which 1.0 g of ammonium persulfate was dissolved in 10 ml of water was added thereto, followed by stirring and mixing. While the stirring was continued, the atmosphere was sufficiently replaced with nitrogen, followed by heating to 65 ° C. to carry out a polymerization reaction for 15 hours. After the completion of the reaction, the solution was analyzed by HPLC, and the residual amount of each monomer was 50 ppm or less based on the polymer.

Example 10 30.0 g of methacrylic acid and 20.0 g of 4-hydroxybutyl acrylate in a flask equipped with a stirrer, a condenser and a nitrogen inlet tube were mixed with 120 ml of dimethyl sulfoxide, 100 ml of 0.17N hydrochloric acid,
It was dissolved in a mixed solvent consisting of 100 ml of 0.85M glycine aqueous solution. 1.0 g of sodium persulfate was added to water 10
The solution dissolved in ml was added and mixed with stirring (glycine / sodium chloride-hydrochloric acid-like buffer system was formed). While the stirring was continued, the atmosphere was sufficiently replaced with nitrogen, followed by heating to 70 ° C. to carry out a polymerization reaction for 12 hours. After the reaction was completed, the solution was analyzed by HPLC.
pm or less.

Example 11 In a flask equipped with a stirrer, a condenser and a nitrogen inlet tube, 28.0 g of 2-methacryloxyethylphosphorylcholine, 8.0 g of 2-hydroxyethyl acrylate and 4.0 g of methyl methacrylate were added to 100 ml of ethyl alcohol. , 0.05M tartaric acid aqueous solution 100
It dissolved in the mixed solvent consisting of ml. A solution prepared by dissolving 1.0 g of sodium persulfate in 10 ml of water was added thereto, followed by stirring and mixing (forming a tartaric acid-sodium tartrate-like buffer system).
While the stirring was continued, the atmosphere was sufficiently replaced with nitrogen, followed by heating to 70 ° C. to carry out a polymerization reaction for 12 hours. After the reaction is completed, the solution is
When analyzed by PLC, the residual amount of each monomer was 50 ppm or less based on the polymer.

Example 12 28.0 g of 2-glucosyloxyethyl methacrylate, 6.0 g of 2-hydroxyethyl acrylate and 6.0 g of butyl methacrylate were placed in a flask equipped with a stirrer, a condenser and a nitrogen inlet tube, and 100 ml of isopropyl alcohol was added. 12M aqueous disodium hydrogen phosphate solution 126.3 ml, 0.1 M aqueous citric acid solution 7
Dissolved in a mixed solvent consisting of 3.7 ml. A solution in which 0.7 g of ammonium persulfate was dissolved in 10 ml of water was added thereto, followed by stirring and mixing. While the stirring was continued, the atmosphere was sufficiently replaced with nitrogen, followed by heating to 70 ° C. to carry out a polymerization reaction for 20 hours. After the completion of the reaction, the solution was analyzed by HPLC, and the residual amount of each monomer was 50 ppm or less based on the polymer.

Example 13 In a flask equipped with a stirrer, a condenser and a nitrogen inlet tube, methoxypolyethylene glycol (23) methacrylate (Shin-Nakamura Chemical NK ester M-2)
30G) 32.0 g, 2-hydroxyethyl methacrylate 16.0 g, 2,2,2-trifluoroethyl methacrylate (Osaka Organic Chemical Biscoat 3FM) 24.0
g, 1H, 1H, 2H, 2H heptadecafluoro n-decyl acrylate (Osaka Organic Chemical Biscoat 17F)
0 g was dissolved in a mixed solvent consisting of 350 ml of isopropyl alcohol and 250 ml of a 0.1 M aqueous citric acid solution.
A solution of 1.5 g of potassium persulfate dissolved in 10 ml of water was added thereto, followed by stirring and mixing (a potassium hydrogen citrate-citrate-like buffer system was formed). While the stirring was continued, the atmosphere was sufficiently replaced with nitrogen, and then heated to 70 ° C. to carry out a polymerization reaction for 15 hours. After the completion of the reaction, the solution was analyzed by HPLC, and the residual amount of each monomer was 50 ppm or less based on the polymer.

Example 14 In a flask equipped with a stirrer, a condenser and a nitrogen inlet tube, methoxypolyethylene glycol (23) methacrylate (Shin-Nakamura Chemical NK ester M-2)
30G) 30.0 g, 2-hydroxyethyl methacrylate 18.0 g, methyl methacrylate 9.0 g, n-octyl acrylate 3.0 g were added to methyl alcohol 100
and 0.1 M potassium dihydrogen phosphate in 200 ml of a mixed solvent. Add ammonium persulfate to this.
A solution prepared by dissolving 7 g in 10 ml of water was added and mixed with stirring.
While the stirring was continued, the atmosphere was sufficiently replaced with nitrogen, followed by heating to 60 ° C. to carry out a polymerization reaction for 12 hours. After the reaction is completed, the solution is
When analyzed by PLC, the residual amount of each monomer was 50 ppm or less based on the polymer.

Example 15 28.0 g of methacrylic acid, 8.0 g of methyl methacrylate, 4.0 g of n-butyl methacrylate in a flask equipped with a stirrer, a condenser and a nitrogen inlet tube.
g was dissolved in a mixed solvent consisting of 120 ml of ethyl cellosolve, 69 ml of a 0.2M borax aqueous solution, and 51 ml of 0.1N hydrochloric acid. 1.2 g of ammonium persulfate was added to water 10
The solution dissolved in ml was added and mixed with stirring. While the stirring was continued, the atmosphere was sufficiently replaced with nitrogen, and then heated to 75 ° C. to carry out a polymerization reaction for 6 hours. After the reaction was completed, the solution was analyzed by HPLC.
pm or less.

Example 16 32.0 g of methacrylic acid and 8.0 g of n-hexyl methacrylate were placed in a flask equipped with a stirrer, a condenser and a nitrogen inlet tube, and 280 m of methyl alcohol was added.
1, 0.1 M aqueous citric acid solution 60 ml, 0.1 N sodium hydroxide aqueous solution 47 ml, and water 13 ml. 0.8 g of potassium persulfate was added to 10 parts of water.
The solution dissolved in ml was added and mixed with stirring (a potassium hydrogen citrate-sodium hydroxide-like buffer system was formed). While continuing stirring, the atmosphere was sufficiently replaced with nitrogen, and then heated to 75 ° C. to carry out a polymerization reaction for 8 hours. After the completion of the reaction, the solution was analyzed by HPLC, and the residual amount of each monomer was 50 ppm or less based on the polymer.

[0026]

According to the present invention, it is possible to provide a means for preventing unreacted monomers from remaining in the process of producing a water-soluble polymer.

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Claims (8)

[Claims] 1. A method for producing a water-soluble polymer by 1) polymerizing or copolymerizing at least one or more of water-soluble monomers as constituent monomers, and 2) ionic or decomposing to a polymerization initiator. Select a substance that produces ions,
3) A method for producing a water-soluble polymer, wherein the solvent is water or an aqueous solution of a water-miscible solvent, and 4) the polymerization is carried out using the solvent as a buffer system. 2. The method according to claim 1, wherein the water-soluble monomer is at least one selected from acrylic acid, methacrylic acid, water-soluble derivatives of acrylic acid and methacrylic acid, and vinylpyrrolidone. 3. The method for producing a water-soluble polymer according to item 1. 3. The method according to claim 1, wherein the water-soluble derivatives of acrylic acid and methacrylic acid are esters with alkylene diols, polyoxyalkylene adducts, phospholipid derivatives and esters with sugars. A method for producing the water-soluble polymer according to the above. 4. The water-soluble derivative of acrylic acid and methacrylic acid is 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, hydroxypropyl methacrylate, hydroxypropyl acrylate, 4-hydroxybutyl methacrylate, 4-hydroxybutyl acrylate, polyethylene glycol mono. Acrylate, polyethylene glycol monomethacrylate, alkoxy polyethylene glycol acrylate, alkoxy polyethylene glycol methacrylate, phenoxy polyethylene glycol acrylate, phenoxy polyethylene glycol methacrylate, 2-glucosiloxyethyl methacrylate, 2-methacryloxyethyl phosphorylcholine. Items 1-3
A method for producing the water-soluble polymer according to any one of the preceding claims. 5. The water-soluble polymer is selected from methacrylic acid esters, acrylic acid esters, fluorinated alkyl group-containing methacrylates or acrylates, styrene and derivatives thereof, and acylated vinyl alcohols as constituent monomers other than water-soluble monomers. The method for producing a water-soluble polymer according to any one of claims 1 to 4, wherein the copolymer is a copolymer containing one or more species. 6. The constituent monomer other than the water-soluble monomer is methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, amyl methacrylate, methacrylic acid. -N-hexyl, cyclohexyl methacrylate, -n-octyl methacrylate, 2-ethylhexyl methacrylate, dodecyl methacrylate, cetyl methacrylate, stearyl methacrylate, benzyl methacrylate, methyl acrylate, ethyl acrylate, n-butyl acrylate , Isobutyl acrylate, tert-butyl acrylate, amyl acrylate, n-hexyl acrylate, cyclohexyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate , Cetyl acrylate, stearyl acrylate, benzyl acrylate, styrene, α
-Methylstyrene, 2,2,2-trifluoroethyl methacrylate, 2,2,2-trifluoroethyl acrylate, 2,2,3,3-tetrafluoropropyl methacrylate, 2,2,3,3-tetrafluoropropyl Acrylate, 1,1,1,3,3,3-hexafluoroisopropyl methacrylate, 1,1,1,3,3,3-hexafluoroisopropyl acrylate, 1H, 1H, 5H-octafluoro-n-pentyl methacrylate, 1H, 1H, 5H-octafluoro-n-pentyl acrylate, 1H, 1H,
2H, 2H-heptadecafluoro-n-decyl methacrylate and 1H, 1H, 2H, 2H-heptadecafluoro-n
The method for producing a water-soluble polymer according to claim 5, wherein one or more kinds selected from -decyl acrylate are used. 7. The water-miscible solvent is one or more selected from methanol, ethanol, isopropyl alcohol, acetone, methyl ethyl ketone, methyl cellosolve, ethyl cellosolve, tetrahydrofuran, dimethylsulfoxide and dimethylformamide. 7. The method for producing a water-soluble polymer according to any one of 1 to 6. 8. The water-soluble polymer according to claim 1, wherein the polymerization initiator is at least one member selected from ammonium persulfate, potassium persulfate, and sodium persulfate. Manufacturing method.