JP2732683B2 - Method for producing fumaric acid copolymer - Google Patents

Description

The present invention relates to a method for producing a fumaric acid copolymer useful as a water treatment agent, a detergent builder, various chelating agents, and the like.

More specifically, the present invention relates to a method for efficiently producing a fumaric acid copolymer having a narrow molecular weight distribution and excellent metal ion capturing ability in an aqueous medium.

[Conventional technology]

Conventionally, fumaric acid copolymers have been used in the fields of, for example, water treatment agents, detergent additives, and various chelating agents. As a publicly known document on such an aqueous production method of the fumaric acid copolymer, JP-A-62-218407 can be mentioned.

However, in the method described in the literature, it is necessary to carry out the reaction in a neutralized state of pH 2 or more, but under this condition, the reaction does not proceed sufficiently and there is a problem that a large amount of residual monomer remains. Was. In addition, the obtained fumaric acid copolymer also has a broad molecular weight distribution, and tends to gel due to complexation with cations such as Ca ions in water, and also has an effect as a water treatment agent and a detergent additive. It was not enough. JP-A-59-12908 describes a method for producing a copolymer of fumaric acid and an allylic alcohol, but also in this method, a large amount of residual fumaric acid remains and the molecular weight distribution is wide. Was not the solution.

JP-B-56-54005 describes a method for producing a fumaric acid copolymer using a monofumarate salt in an aqueous medium.However, even with this method, a polymer having a narrow molecular weight distribution can be obtained. I could not do it. Also, JP-A-56-99
No. 212 describes that a fumaric acid / acrylic acid copolymer can be obtained at a high yield in a solvent system.

However, this production method is not an advantageous method from the viewpoints of disaster prevention, cost, and resource saving, because not only the number of steps is increased but also polymerization is performed in an organic solvent such as toluene and chlorobenzene. . In addition, solvents such as toluene and chlorbene remain in the product, leaving a problem in terms of safety.

Therefore, there has been a demand for a technique for obtaining a high yield of a fumaric acid copolymer having a narrow molecular weight distribution and being useful as a water treatment agent and a detergent additive in an aqueous system.

[Problems to be solved by the invention]

The present invention has been made to solve such problems of the prior art, useful fumaric acid copolymer having a low molecular weight and a narrow molecular weight distribution, particularly useful as a water treatment agent and a detergent additive, It is an object of the present invention to provide a method for economical production with simple steps.

[Means for solving the problem]

The present invention relates to 30 to 70% by weight of fumaric acid (a) and 70 to 30% by weight of another water-soluble unsaturated monomer (b) (however, fumaric acid (a) and water-soluble unsaturated monomer (b) Is 100% by weight.) In the polymerization of the monomer component consisting of the following components in an aqueous medium, the monomer component is selected from the group consisting of vanadium atom-containing ions, iron ions and copper ions in an amount of 0.5 to 500 ppm based on the monomers. Characterized in that, in the presence of one or more metal ions, 3-100 g of hydrogen peroxide (1 mol relative to the monomer component) is used as a polymerization catalyst, and the pH during polymerization is less than 2. The present invention relates to a method for producing an acid copolymer.

Examples of the aqueous medium that can be used in the present invention include water and a monohydric alcohol having 1 to 4 carbon atoms or 3 carbon atoms.
To 4 mixed solvents.

Examples of the alcohol used include methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, ter-butanol and the like. Also,
Examples of the ketone used include acetone, methyl ethyl ketone, and the like.

However, in order to reduce the residual monomer and obtain a fumaric acid copolymer having a narrow molecular weight distribution, the copolymerization is preferably carried out in a completely aqueous system.

In the present invention, the other water-soluble unsaturated monomer (b) used as a copolymerization component of fumaric acid (a) in producing the fumaric acid copolymer is not particularly limited, but for example, acrylic acid , Methacrylic acid, α-hydroxyacrylic acid, crotonic acid and other unsaturated monocarboxylic acid monomers and salts thereof; maleic acid, itaconic acid, citraconic acid, aconitic acid and other unsaturated polycarboxylic acid monomers And salts thereof: vinyl acetate; general formula (1) (Wherein, R ¹ and R ² each independently represent hydrogen or a methyl group, R ¹ and R ² are not simultaneously a methyl group, and R ³ is —CH ₂ —, — (CH ₂ ) ₂ - or -C (CH _3)
2 - represents and R ^1, the total number of carbons in R ² and R ³ are 3, Y represents an alkylene group having 2 to 3 carbon atoms, n represents 0
Or an integer of 1 to 100. ), For example, 3
-Methyl-3-buten-1-ol (isoprenol), 3-methyl-2-buten-1-ol (prenol), 2-methyl-3-buten-2-ol (isoprene alcohol) and these monomers 1 1 mole of ethylene oxide and / or propylene oxide per mole
Unsaturated hydroxyl group-containing monomer such as a monomer having an addition of 100 to 100 mol; General formula (2) (Wherein, R ¹ represents hydrogen or a methyl group, and a, b,
d and f are and a + b + d + f = 0~100 represent each independently an integer of 0 or 1~100, -0C ₂ H ₄ - unit and -0C ₃ H ₆ - is a unit attached to any order When d + f is 0, Z represents a hydroxyl group, a sulfonic acid group and a (phosphite) phosphoric acid group, and when d + f is a positive integer of 1 to 100, Z represents a hydroxyl group. For example, 3-allyloxy-2-hydroxypropanesulfonic acid and a salt thereof; glycerol monoallyl ether and a monomer obtained by adding 1 to 100 moles of ethylene oxide and / or propylene oxide to 1 mole of these monomers (Meth) allyl ether-based monomers such as isomers; vinylsulfonic acid, allylsulfonic acid, methallylsulfonic acid, styrenesulfonic acid, 2-acrylamide-
2-methylpropanesulfonic acid, sulfoethyl (meth)
Acrylate, sulfopropyl (meth) acrylate,
2-hydroxysulfopropyl (meth) acrylate,
Unsaturated sulfonic acid group-containing monomers such as sulfoethylmaleimide and salts thereof: an alcohol obtained by adding 0 to 100 moles of ethylene oxide and / or propylene oxide to an alkyl alcohol having 1 to 20 carbon atoms, and (meth) acrylic acid; Monoester such as crotonic acid or monoester with maleic acid, fumaric acid, itaconic acid, citraconic acid, aconitic acid or the like, or an ester-based unsaturated monomer having a terminal alkyl group such as a salt or diester; For unsaturated carboxylic acid monomers such as (meth) acrylic acid and crotonic acid, ethylene oxide and / or
Alternatively, ethylene oxide and / or monoester monomer to which 1 to 100 mol of propylene oxide is added, or unsaturated polycarboxylic acid monomer such as maleic acid, fumaric acid, itaconic acid, citraconic acid, and aconitic acid are used.
Or a monoester to which 1 to 100 mol of propylene oxide is added, or a salt thereof, or an ester-based unsaturated monomer such as a diester-based monomer, and one or two kinds selected from these groups. The above can be used.

The proportion of fumaric acid (a) to other water-soluble unsaturated monomer (b) must be in the range of 30 to 70% by weight of the former and 70 to 30% by weight of the latter. When fumaric acid (a) exceeds 70%, the residual monomer increases. When the fumaric acid (a) is less than 30%, the molecular weight distribution of the obtained fumaric acid copolymer is widened.

Next, examples of the metal ions used in the present invention include iron ions, vanadium atom-containing ions, and copper ions, among which Fe ³⁺ , Fe ²⁺ , Cu ⁺ , Cu ²⁺ , V ²⁺ , V ^3+, V0 ^2+, V0 ₃ ^-
Is preferred. Particularly preferred metal ions are Fe ³⁺ , Cu ²⁺ , V02 ⁺
One or two or more selected from the group of these metal ions can be used. Metal ions are
It is necessary to use it in the range of 0.5 to 500 ppm with respect to the monomer component, and it is desirable to use 5 to 100 ppm.
If the amount of the metal ion is less than this range, the copolymerization ratio will not be improved. In addition, when metal ions are used in an amount larger than this range, not only does the product contaminate and cause coloration problems, but the molecular weight distribution of the produced fumaric acid copolymer expands, and water treatment agents and detergent additives are used. As the performance is reduced.

There is no particular limitation on the supply form of the metal ions, and any metal ions can be used as long as they can be ionized in the polymerization reaction system. Examples of such a metal compound include vanadium oxytrichloride, vanadium trichloride, vanadyl oxalate, vanadyl sulfate, vanadic anhydride, ammonium metavanadate, and ammonium hypovanadas sulfate ((NH ₄ ) ₂ SO ₄ .VSO _4. 6H ₂ O], ammonium sulfate vanadas [(NH ₄ ) V (SO ₄ ) ₂ · 12H ₂ O], copper acetate (I
I), copper (II) bromide, copper (II) acetylacetate, cupric ammonium chloride, copper carbonate, copper (II) chloride, copper (II) citrate, copper (II) formate, copper (II) hydroxide ), Copper nitrate,
Copper naphthenate, copper oleate, copper maleate, copper phosphate, copper (II) sulfate, cuprous chloride, copper (I) cyanide, copper iodide, copper (I) oxide, copper thiocyanate, iron acetyl Acetate, ferric ammonium citrate, ferric ammonium oxalate, ferrous ammonium sulfate, ferric ammonium sulfate, iron citrate, iron fumarate, iron maleate, ferrous lactate, ferric nitrate, iron penta Water-soluble metal salts such as carbonyl, ferric phosphate and ferric pyrophosphate; metal oxides such as vanadium pentoxide, copper (II) oxide, ferrous oxide and ferric oxide; copper (II) sulfide Metal sulfides, such as iron sulfide;
Other examples include copper powder and iron powder.

In order to further adjust the concentration of metal ions, for example,
Condensed phosphoric acid systems such as pyrophosphoric acid, hexametaphosphoric acid, and tripolyphosphoric acid: aminocarboxylic acid systems such as ethylenediaminetetraacetic acid, nitrilotriacetic acid, and diethylenetriaminepentaacetic acid: 1-hydroxyethylidene-1,1-diphosphonic acid, 2-phosphonobutane-1, Phosphonic acid system such as 2,4-tricarboxylic acid: organic acid system such as malic acid, citric acid, itaconic acid, oxalic acid, crotonic acid; complex forming agent such as polycarboxylic acid system such as polyacrylic acid; It is also possible to use together.

The polymerization temperature is preferably in the range of 50 to 160 ° C, more preferably 70 to 160 ° C, for the purpose of shortening the polymerization time. More preferably, it is 85 to 150 ° C. If the temperature is lower than 50 ° C., the progress of polymerization may be inhibited. On the other hand, when the temperature exceeds 160 ° C., a thermal decomposition reaction is expected. The concentration of the solid content at the time of polymerization can be carried out in a wide range, but 20 to 70%, more preferably
The range of 30 to 60% is preferable because the residual fumaric acid can be further reduced.

It is necessary to carry out the polymerization at a pH of less than 2, and more preferably pH 1.5 or less. When the polymerization is carried out at pH 2 or more, the molecular weight distribution is widened and the performance as a water treatment agent is not sufficient.

The basic compound for neutralization used to maintain the pH at less than 2 during the polymerization is not particularly limited. For example, hydroxides and carbonates of alkali metals such as sodium, potassium and lithium; ammonia; monomethylamine, diethylamine,
Alkylamines such as trimethylamine, monoethylamine, dimethylamine and triethylamine; alkanolamines such as monoethanolamine, diethanolamine, triethanolamine, isopropanolamine and secondary butanolamine; and pyridine.

Also, fumaric acid (a) and other water-soluble monomers (b)
Can of course be used as these salts.

In the present invention, hydrogen peroxide is used as a polymerization catalyst. It is necessary to use 3 to 100 g of hydrogen peroxide per 1 mol of the monomer component in the present invention. A more preferable range is 8 to 80 g per 1 mol of the monomer component, and the most preferable range is 11 to 50 g. Hydrogen peroxide is 3
If it is less than g, the amount of residual monomer increases. Conversely 100g
Even if it is used more, not only the effect corresponding to the increased amount of hydrogen peroxide is not obtained, but also a problem of hydrogen peroxide remaining in the product is caused.

The method for supplying hydrogen peroxide into the polymerization system is not particularly limited. For example, initial batch charging may be performed in the reaction system, or continuous charging may be performed during the reaction. In some cases, it is possible to divide and input. However, in order to make the polymerization reaction proceed more smoothly, it is preferable to use continuous feeding.

In the present invention, a polymerization catalyst other than hydrogen peroxide, for example, persulfates such as ammonium persulfate, sodium persulfate and potassium persulfate; 2,2'-azobis (2-amidinopropane)
Azo compounds such as hydrochloride, 4,4'-azobis-4-cyanovaleric acid, azobisisobutyronitrile, 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile, benzoyl peroxide, Organic peroxides such as lauroyl peroxide, peracetic acid, persuccinic acid, ditertiary butyl peroxide, tertiary butyl hydroperoxide, cumene hydroperoxide, etc., together with hydrogen peroxide, as long as the effects of the present invention are not impaired. It is possible to use.

〔The invention's effect〕

The fumaric acid copolymer obtained by the method of the present invention configured as described above has a number average molecular weight of 30 to 5000, preferably 400 to 4000, and a D value (M
(W / MN) [MW is a weight average molecular weight, MN is a number average molecular weight] and has characteristics of 2.5 or less, preferably 2.0 or less.

The method of the present invention provides a method for economically producing a fumaric acid copolymer having the above characteristics in an aqueous medium at a high yield, and the above-described water treatment agent, detergent additive, and Refining aid for cellulose fiber, bleaching aid for cellulose fiber, dyeing aid for cellulose fiber, pulp bleaching pretreatment agent, adjuster for bentonite muddy water, iron, copper, manganese,
It can be very suitably used for a wide range of applications such as a deodorant, an inorganic pigment dispersant, a deinking aid for recycling used paper, and a chelating agent in combination with a polyvalent metal such as zinc.

〔Example〕

Hereinafter, the present invention will be described specifically with reference to examples.
The present invention is not limited to these examples.
In addition,% and part in an example show a weight% and weight part, respectively.

Example 1 In a five-necked four-necked flask equipped with a thermometer, a stirrer, and a reflux condenser, 1160 parts of fumaric acid, 1000 parts of ion-exchanged water, 0.163 parts of ammonium iron (II) sulfate hexahydrate (Fe ²⁺ And the dispersion was heated to the boiling temperature under normal pressure while stirring. Next, 1450 parts of an aqueous 80% acrylic acid solution and
867 parts of a 60% aqueous hydrogen peroxide solution (20 g; based on 1 mole of the charged monomer component) were continuously dropped from respective dropping nozzles continuously over 3 hours to carry out copolymerization. After the completion of the dropwise addition, the mixture was further stirred at the boiling temperature of the system for 1 hour to complete the copolymerization reaction, thereby obtaining a homogeneous fumaric acid copolymer (1) having a solid content of 51.8%. The pH during polymerization (stock solution, measured at 80 ° C.) was 0 to 0.5.

The molecular weight and molecular weight distribution of the obtained fumaric acid copolymer (1) were measured by using gel permeation chromatography. The results were as shown in Table 1.

The column is Tosoh G-3000PW (XL) + G-2500
Use PW (XL) as eluent, phosphate buffer (pH 7)
Was used. Polyethylene glycol (manufactured by General Science) was used as a molecular weight standard sample.

Examples 2 to 8 Kinds and amounts of metal ions used in Example 1,
The fumaric acid copolymers (2) to (8) were prepared in exactly the same manner as in Example 1 except that the amount of hydrogen peroxide used and the amount of the 80% aqueous acrylic acid solution added dropwise were as shown in Table 1. I got The obtained fumaric acid copolymers (2) to (8) were analyzed in the same manner as in Example 1, and the results are shown in Table 1.

Example 9 A fumaric acid copolymer (9) was obtained in exactly the same manner as in Example 1 except that 100 parts of a 48% aqueous sodium hydroxide solution was charged during the preparation. The obtained fumaric acid copolymer (9) was analyzed in the same manner as in Example 1, and the result was analyzed by the first method.
It is shown in the table.

Examples 10 to 16 In Example 1, the water-soluble unsaturated monomer (b) used
The fumaric acid copolymers (10) to (16) were obtained in exactly the same manner as in Example 1, except that the kind of the metal ion used and the kind and amount of the metal ion used were as shown in Table 1. The obtained fumaric acid copolymers (10) to (16) were analyzed in the same manner as in Example 1, and the results are shown in Table 1.

Example 17 A fumaric acid copolymer (17) was obtained in the same manner as in Example 1 except that 200 parts of a 48% aqueous sodium hydroxide solution was charged at the time of charging. The obtained fumaric acid copolymer (17) was analyzed in the same manner as in Example 1, and the result was analyzed as
It is shown in the table.

Example 18 A fumaric acid copolymer (18) was obtained in the same manner as in Example 1 except that 50 parts of isopropanol was charged during the preparation. The obtained fumaric acid copolymer (18)
Was analyzed in the same manner as in Example 1, and the results are shown in Table 1.

Comparative Example 1 A comparative fumaric acid copolymer (1) was obtained in exactly the same manner as in Example 1 except that ammonium iron (II) sulfate hexahydrate was not used at all. The obtained comparative fumaric acid copolymer (1) was analyzed in the same manner as in Example 1, and the results are shown in Table 2.

Comparative Examples 2 to 4 Comparative fumaric acid copolymers (2) to (4) were prepared in exactly the same manner as in Example 1 except that the types and amounts of metal ions used in Example 1 were as shown in Table 2. ) Got. The obtained comparative fumaric acid copolymers (2) to (4) were analyzed in the same manner as in Example 1, and the results are shown in Table 2.

Comparative Examples 5 and 6 In the same manner as in Example 1, except that 1214 parts of a 48% aqueous sodium hydroxide solution was charged at the time of preparation and the types and amounts of metal ions were as shown in Table 2, Thus, comparative fumaric acid copolymers (5) and (6) were obtained. The obtained comparative fumaric acid copolymers (5) and (6) were analyzed in the same manner as in Example 1, and the results are shown in Table 2.

Comparative Examples 7 and 8 Comparative fumaric acid copolymers (7) and (8) were prepared in exactly the same manner as in Example 1 except that the amount of acrylic acid used in Example 1 was as shown in Table 2. Obtained. The obtained comparative fumaric acid copolymers (7) and (8) were analyzed in the same manner as in Example 1, and the results are shown in Table 2.

Examples 19 to 36 Fumaric acid copolymers (1) obtained in Examples 1 to 18
The following test was performed to evaluate the performance of (18) as a scale inhibitor. Fill a 225 ml glass bottle with water
70 g, 10 g of 1.56% calcium chloride dihydrate aqueous solution, and 3 g of 0.02% aqueous solution of fumaric acid copolymers (1) to (18)
(3 ppm based on the resulting supersaturated aqueous solution), and 10 g of a 3% aqueous sodium bicarbonate solution and 7 g of water were added to make a total amount of 200 g. The obtained 530 ppm supersaturated aqueous solution of calcium carbonate was sealed and heated at 70 ° C. for 3 hours. Next, after cooling, the precipitate was filtered with a 0.1 μm membrane filter, and the filtrate was analyzed according to JIS K0101.

The calcium carbonate scale inhibition rate (%) was determined by the following equation. The results obtained are shown in Table 3.

A: The concentration of calcium dissolved in the solution before the test B: The potassium concentration in the filtrate without the scale inhibitor C: The calcium concentration in the filtrate after the test Comparative Examples 9 to 16 In exactly the same manner as in Examples 18 to 34 The comparative fumaric acid copolymers (1) to (8) obtained in Comparative Examples 1 to 8 were evaluated for performance as scale inhibitors. Table 4 shows the obtained results.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yoshio Irie 992, Nishioki, Okahama-ku, Himeji-shi, Hyogo Pref. Address No. 1 Kenichi Hara, Examiner, Himeji Laboratory, Nippon Shokubai Chemical Industry Co., Ltd.

Claims (4)

(57) [Claims] (1) 30 to 70% by weight of fumaric acid (a) and 70 to 30% by weight of another water-soluble unsaturated monomer (b) (provided that fumaric acid (a) and water-soluble unsaturated monomer (b) ) Is 100% by weight
It is. ) Is polymerized in an aqueous medium, and is selected from the group consisting of 0.5 to 500 ppm of a vanadium atom-containing ion, an iron ion and a copper ion with respect to the monomer component. A fumaric acid copolymer, characterized in that 3 to 100 g of hydrogen peroxide (based on 1 mol of monomer component) is used as a polymerization catalyst in the presence of at least one kind of metal ion, and the pH during polymerization is less than 2; Production method. 2. The method for producing a fumaric acid copolymer according to claim 1, wherein the water-soluble unsaturated monomer (b) is (meth) acrylic acid (salt). 3. The method for producing a fumaric acid copolymer according to claim 1, wherein the pH during the polymerization is 1.5 or less. 4. The method for producing a fumaric acid copolymer according to claim 1, wherein the aqueous medium is water.